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MA EPHT All Inclusive glossary

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Absorption - The process of taking in. For a person or an animal, absorption is the process of a substance getting into the body through the eyes, skin, stomach, intestines, or lungs.

Action Levels - (1) Regulatory levels recommended by U.S. Environmental Protection Agency (U.S. EPA) for enforcement by the U.S. Food & Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) for pesticide residues in food or feed commodities; (2) In the Superfund program, the existence of a contaminant concentration in the environment high enough to warrant a response under the Superfund Amendments & Reauthorization Act (SARA) and the National Oil and Hazardous Substances Contingency Plan; (3) For drinking water, the level of lead or copper which, if exceeded, triggers treatment or other requirements that a public water system must follow.

Acute - Occurring over a short time [compare with Chronic].

Acute Effect - An adverse effect on any living organism which results in severe symptoms that develop rapidly; symptoms often subside after the exposure stops.

Acute Myocardial Infarction (AMI) - [see Myocardial Infarction].

Acute Exposure - Contact with a substance that occurs once or for only a short time (up to 14 days) [compare with Chronic Exposure].

Additive Effect - A biologic response to exposure to multiple substances that equals the sum of responses of all the individual substances added together [compare with Antagonistic Effect].

Adverse Health Effect - A change in body function or cell structure that might lead to disease or health problems.

Aerobic - Requiring oxygen [compare with Anaerobic].

Age-adjusted Rate - A statistical method applied to the rates of a disease in a population that allows comparison among populations with different age distributions; also known as age-standardized rate.

Agency for Toxic Substances and Disease Registry (ATSDR) - Based in Atlanta, Georgia, a federal public health agency of the U.S. Department of Health and Human Services.

Age-specific Rate -The rate measured in a particular age group. The numerator and the denominator for this rate refer to the same age group.

Age-standardized Rate (ASR) - A summary measure of a rate that a population would have if it had a standard age structure (for example, the age distribution of the U.S. Census population). Standardization is necessary when comparing several populations that differ with respect to age because age has a powerful influence on the risk of many diseases.  

Air - "Pure" air is a mixture of gases containing about 78 percent nitrogen; 21 percent oxygen; less than 1 percent of carbon dioxide, argon, and other gases; and varying amounts of water vapor [compare with Ambient Air].

Airborne Release - Release of any pollutant into the air.

Air Monitoring - Sampling for and measuring of pollutants present in the atmosphere.

Air Pollutant - Any substance in air that could, in high enough concentration, be harmful to humans, other animals, vegetation, or materials. They may be in the form of solid particles, liquid droplets, gases, or in combination.

Air Pollution - The presence of air pollutants in the air.

Air Pollution Episode - A period of abnormally high concentration of air pollutants, often due to low winds and temperature inversion, which can cause illness and death.

Air Quality Criteria - The levels of pollution and lengths of exposure above which adverse health and welfare effects may occur.

Air Quality Index (AQI) - A numerical index developed by the U.S. EPA for reporting the severity of daily air pollution levels to the public. U.S. EPA calculates an AQI for five air pollutants - ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. AQI levels range from 0 (good air quality) to 500 (hazardous air quality). The higher the index, the higher the level of pollutants and the greater the likelihood of health effects. The AQI incorporates an additional index category - unhealthy for sensitive groups - that ranges from 101 to 150.

Air Quality Standards - The level of pollutants prescribed by regulations that are not be exceeded during a given time in a defined area.

Air Toxics - Any air pollutant for which a national ambient air quality standards (NAAQS) does not exist (i.e. excluding ozone, carbon monoxide, PM10, sulfur dioxide, nitrogen oxide) that may reasonably be anticipated to cause cancer; respiratory, cardiovascular, or developmental effects; reproductive dysfunctions, neurological disorders, heritable gene mutations, or other serious or irreversible chronic or acute health effects in humans. Also known as hazardous air pollutants (HAPs).

Ambient Air - Any unconfined portion of the atmosphere: open air, surrounding air.

Ambient Measurement - A measurement of the concentration of a substance or pollutant within the immediate environment of an individual; a measurement taken to relate it to the amount of possible exposure.

Anaerobic - Requiring the absence of oxygen [compare with Aerobic].

Analyte - A chemical for which a sample (such as water, air, or blood) is tested in a laboratory. For example, if the analyte is mercury, the laboratory test will determine the amount of mercury in the sample.

Analytic Epidemiologic Study - A study that evaluates the association between exposure to hazardous substances and disease by testing scientific hypotheses.

Anemia - Anemia is a condition in which you don't have enough healthy red blood cells to carry adequate oxygen to your tissues.

Anencephaly - Congenital absence of the skull and brain.

Antagonistic Effect - A biologic response to exposure to multiple substances that is less than would be expected if the known effects of the individual substances were added together [compare with Additive Effect].

Aorta - A major artery that carries blood from the heart to be distributed throughout the body. 

Aplastic Anemia - A disease in which the bone marrow and blood stem cells are damaged. This damage causes a deficiency of all three blood cell types; white blood cells, red blood cells, and platelets. The disease prevents the regeneration of mature blood cells, causing low blood cell counts.

Aquifer - A natural underground layer, often of sand or gravel, which contains water.

Arsenic - A metal that occurs naturally in the Earth’s crust in soil, rocks, and minerals.

Asthma - A chronic inflammatory pulmonary disorder that is characterized by reversible obstruction of the airways and recurrent episodes of breathlessness and wheezing that can be life-threatening. Many factors contribute to airflow limitation in asthma, each related to the inflammatory process.

Asthma Management - A comprehensive approach to achieving and maintaining control of asthma, including patient education to develop a partnership in management, assessing and monitoring severity, avoiding or controlling asthma triggers, establishing plans for medication and management of exacerbations, and regular follow-up care.

Atmosphere - The gaseous mass or envelope of air surrounding the earth. From the ground-level up, the atmosphere is further subdivided into the troposphere, stratosphere, mesosphere and the thermosphere.  

Atresia - Congenital absence or closure of a normal anatomical opening.

ATSDR - The Agency for Toxic Substances & Disease Registry, based in Atlanta, Georgia is a federal public health agency of the U.S. Department of Health and Human Services.

Attainment Area - An area considered to have air quality as good as or better than the national ambient air quality standards (NAAQS) as defined in the Clean Air Act. An area may be an attainment area for one pollutant and a non-attainment area for others.

Average - Numerical result obtained by dividing the sum of values of a factor (such as age of children) by the number of factors (e.g. number of children). Also known as mean.

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Background Level - An average or expected amount of a substance or radioactive material in a specific environment, or a typical amount of a substance that occurs naturally in an environment.

Bakery - Means a facility that produce bread, cakes, pies, or other food products made either wholly or in part of flour, and intended for wholesale commerce.

Bakery Product - Means baked products including bread, cookies, pies, pretzels, and pastries.

Benzo(a)pyrene (BaP) - One of a group of compounds called polycyclic aromatic hydrocarbons (PAHs).

Biodegradation - Decomposition or breakdown of a substance through the action of microorganisms (such as bacteria or fungi) or other natural physical processes (such as sunlight).

Biologic Indicators of Exposure Study - A study that uses (a) biomedical testing or (b) the measurement of a substance (an analyte), its metabolite, or another marker of exposure in human body fluids or tissues to confirm human exposure to a hazardous substance [see Exposure Investigation].

Biologic Monitoring - Measuring hazardous substances in biologic materials (such as blood, hair, urine, or breath) to determine whether exposure has occurred; also known as biomonitoring. A blood test for lead is an example of biologic monitoring.

Biologic Uptake - The transfer of substances from the environment to plants, animals, and humans.

Biomedical Testing - Testing of persons to find out whether a change in a body function might have occurred because of exposure to a hazardous substance.

Biota - Plants and animals in an environment. Some of these plants and animals might be sources of food, clothing, or medicines for people.

Birth Defect - Congenital abnormalities of structure, function or metabolism present before birth.

Birth Order - Birth order is the chronological order of sibling births in a family.

Bladder Cancer - Cancer that forms in tissues of the bladder, the organ that stores urine.

Blood Lead Level (BLL) - The concentration of lead in a sample of blood usually expressed in micrograms per deciliter (µg/dL).

Body Burden - The total amount of a substance in the body. Some substances build up in the body because they are stored in fat or bone or because they leave the body very slowly.

Bottled Water - Means bottled drinking water.

Breast Cancer - Cancer that forms in tissues of the breast, usually the ducts, tubes that carry milk to the nipple, and/or lobules, glands that make milk.

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Cancer - Any one of a group of diseases that occur when cells in the body become abnormal and grow or multiply out of control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

Cancer Cluster - Because cancer is a common disease, it often appears to occur in “clusters,” and it is understandable that someone may perceive that there are an unusually high number of cancer cases in their surrounding neighborhood or community. A suspected cluster is more likely to be a true cancer cluster if it involves a large number of cases of one type of cancer diagnosed in a relatively short time period rather than several different types diagnosed over a long period of time (i.e., 20 years), a rare type of cancer rather than a common type, and a large number of cases diagnosed among individuals in age groups not usually affected by that cancer. 

Cancer Risk - A theoretical risk for getting cancer if exposed to a substance every day for 70 years (a lifetime exposure). The true risk might be lower.

Capillary - Type of testing for blood lead that involves the drawing of blood from a capillary such as through a finger prick. This type of testing is considered less accurate than venous testing.

Carbon Dioxide (CO2) - A colorless, odorless gas that occurs naturally in the Earth's atmosphere. Significant quantities are also emitted into the air by fossil fuel combustion.

Carbonated Non-alcoholic Beverage - Means a carbonated beverage of any flavor containing no alcohol and includes, but is not limited to, soda water, seltzer water, carbonated water, tonic water, and sparkling water made with added carbon dioxide.

Carbon Monoxide (CO) - An odorless, colorless gas that can cause sudden illness and death. Carbon Monoxide is found in combustion fumes, such as those produced by cars and trucks, small gasoline engines, stoves, lanterns, burning charcoal and wood, and gas ranges and heating systems.

Carbon Monoxide Detectors - A device that detects the presence of the poisonous gas carbon monoxide, a colorless and odorless compound produced by incomplete combustion and lethal at high levels.

Carbon Monoxide Poisoning - Illness that results from exposure to carbon monoxide. The most common symptoms are headache, dizziness, weakness, nausea, vomiting, chest pain, and confusion.  In severe cases, can cause death by asphyxiation.

Carcinogen - A substance that causes cancer.

Cardiovascular Disease - Any disease involving the heart or blood vessels.

CDC (U.S. Centers for Disease Control & Prevention) - The agency charged with tracking and investigating public health trends. The stated mission of the Centers for Disease Control and Prevention is "to promote health and quality of life by preventing and controlling disease, injury, and disability."

Cell Suppression - A statistical method used to report aggregate health data in tables that restricts or suppresses the release of aggregate health data in order to protect the identity and privacy of individuals and to avoid the risk of identification of individuals in small population groups. For most datasets, the cell suppression rule is to not release numbers or rates when the number of events (e.g., number of cancer cases among females in a community) is less than 6 and the population (e.g., number of females in the community) is less than 1,200. The cell suppression rule for hospitalization data is different than other health outcomes. A cell suppression rule applies only to confidential health data and not data otherwise available to the public, such as air pollution data.

Census Block - Bounded on all sides by visible features, such as streets, roads, streams, and railroad tracks, and by non-visible boundaries such as city, town, township, and county limits, and short line-of-sight extensions of streets and roads. Often the size of a city block in urban areas; their size varies in other parts of the state.

Census Block Groups - Clusters of blocks within the same census tract that have the same first digit of their 4-digit census block number. The Block Group boundaries were used to create the Massachusetts Environmental Justice 2010 Populations data.

Census Tract (CT) - A small, relatively permanent geographic subdivision of a city or town designated by the United States Census Bureau. CTs usually contain between 2,500 and 8,000 persons and are designed to be homogenous with respect to population characteristics, economic status, and living conditions. The spatial size of census tracts varies widely depending on the density of settlement. Census tract boundaries are delineated with the intention of being maintained over a long time so that statistical comparisons can be made from census to census. However, physical changes in street patterns caused by highway construction, new development, etc., may require occasional revisions; census tracts occasionally are split due to large population growth, or combined as a result of substantial population decline. (U.S. DOC 2000). 

Centers for Disease Control - [see CDC].

Central Nervous System - The part of the nervous system that consists of the brain and the spinal cord.

CERCLA - [see Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA)].

Cerebral Palsy - A general term for a group of disorders that appear during the first few years of life and affect a child's ability to coordinate body movements. Cerebral palsy can cause muscles to be weak and floppy, or rigid and stiff.

Cerebrovascular Disease -Range of disorders in which an area of the brain is temporarily or permanently affected by a loss of blood supply involving one or more blood vessels.

Chemical Contaminants - Chemicals in the environment that cause harm or discomfort to humans or other living organisms or that damage the environment.

Child - For blood lead testing, any person age 9 to 47 months at the time of screening.

Child Match - The process of “de-duplicating” the Child Lead Poisoning Prevention Program (CLPPP) data file so that each child is counted only once. For example, one child could be accidentally entered twice into a data file or a child could have had more than one blood test. For MA EPHT purposes, only one child and only one test for that child is counted.

Childhood Lead Poisoning Prevention Program (CLPPP)- The CLPPP was established for the prevention, screening, diagnosis, and treatment of lead poisoning, including the elimination of sources of poisoning through research and educational, epidemiologic, and clinical activities as may be necessary. CLPPP provides a range of both primary and secondary prevention services to the children of the Commonwealth of Massachusetts, their families and others with an interest in the prevention of lead poisoning.

Chromosome - An organized structure of DNA which contains genetic material.  Normally, people have 23 pairs of chromosomes for a total of 46.

Chronic - Occurring over a long time [compare with Acute].

Chronic Effect - An adverse effect on a human or animal in which symptoms recur frequently or develop slowly over a long period of time.

Chronic Exposure - Multiple exposures occurring over an extended period of time or over a significant fraction of an animal's or human's lifetime (usually seven years to a lifetime) [compare with Acute Exposure].  

Chronic Obstructive Pulmonary Disease (COPD) - Any disorder, such as asthma, chronic bronchitis, or pulmonary emphysema, marked by persistent obstruction of bronchial air flow.

Circulatory - The organs and tissues involved in circulating blood and lymph through the body.

Clean Air Act - The federal law that defines U.S. EPA’s responsibilities for protecting and improving the nation’s air quality and the stratospheric ozone layer.

Cleft Lip - Congenital defect of the upper lip in which there is incomplete closure.

Cleft Palate - Congenital defect in the closure of the palate (the structure which separates the nasal cavities and the back of the mouth). May involve the soft palate, hard palate or alveolus (gum).

Cluster Investigation - A review of an unusual number, real or perceived, of health events (for example, reports of cancer) grouped together in time and location. Cluster investigations are designed to confirm case reports; determine whether they represent an unusual disease occurrence; and, if possible, explore possible causes and contributing environmental factors.

Collaborative - Educational collaboratives are formed through an agreement among two or more school committees to provide educational programs or services for their member school systems. Collaboratives are managed by a Board representative from each member school committee, and are funded through local public school committee budgets.

Combustion - The heat-producing reaction of a material with oxygen gas or other oxidant, often producing a flame.

Community - There are 351 communities in Massachusetts, for more information [see the Cities and Towns Comprehensive Information link in the links page].

Community Multiscale Air Quality Model - A model in which emission and meteorological data are run through computer code that simulates physical and chemical processes in the atmosphere to provide estimated concentrations of pollutants.

Community Water System (CWS) -Any water system that provides water for human consumption through pipes or other constructed conveyances to at least 15 service connections or serves an average of at least 25 people for at least 60 days a year.  Also known as Public Water System (PWS)

Compliance - The act of meeting all state and federal regulations.

Compliance Period - For drinking water, the time period that public water systems must monitor for contaminants in order to meet all state and federal drinking water regulations.  

Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) - CERCLA, also known as Superfund, is the federal law that concerns the removal or cleanup of hazardous substances in the environment and at hazardous waste sites. ATSDR, which was created by CERCLA, is responsible for assessing health issues and supporting public health activities related to hazardous waste sites or other environmental releases of hazardous substances. This law was later amended by the Superfund Amendments and Reauthorization Act (SARA).

Concentration - The amount of a substance present in a certain amount of soil, water, air, food, blood, hair, urine, breath, or any other media.

Confidence Interval - A CI, usually 95% CI, is the range of estimated values that has a 95% probability of including the true value for the population. If the 95% CI range does not include the value 100, then the study population is significantly different from the comparison or “normal” population. “Significantly different” means there is less than 5% percent chance that the observed difference (either increase or decrease) in the rate is the result of random fluctuation in the number of observed diagnoses.

Confidentiality - Information, such as medical information or income, which is legally defined as private. This type of information is generally not permitted to be revealed when the individual could be identified without the consent of the individual.

Congenital - Present at birth, includes conditions and defects detected prenatally and those not recognized until after the newborn period.

Consumer Confidence Rule (CCR) - An annual report on public drinking water quality that is required to be provided to customers of public water supplies by community public water suppliers.  This report is mandated by the federal Safe Drinking Water Act to be delivered to customers by July 1.  The Massachusetts Department of Environmental Protection (DEP) is authorized to enforce the CCR rule.

Contaminant - A substance that is either present in an environment where it does not belong or is present at levels that might cause harmful (adverse) health effects.

Contamination - Introduction into water, air, and/or soil of microorganisms, chemicals, toxic substances, wastes, or wastewater in a concentration that makes the medium unfit for its intended use. Also applies to surfaces of objects, buildings, and various household and agricultural use products.

Content Work Group - A workgroup of the CDC National Environmental Public Health Tracking Program [see Environmental Public Health Tracking] tasked to define appropriate core data and measures to track.

Continuous Sample - A flow of water, waste or other material from a particular place in a facility to the location where samples are collected for testing. May be used to obtain grab or composite samples.

Coronary Heart Disease - Coronary heart disease (CHD) is the most common type of heart disease. CHD occurs when the coronary arteries, that supply blood to the heart muscle, become hardened and narrowed due to plaque buildup. Plaque buildup and the narrowing and hardening of the arteries is called atherosclerosis. Plaque is a mixture of fatty substances including cholesterol and other lipids. Blood flow and oxygen supply to the heart can be reduced or even fully blocked with a growing plaque. Plaque may also rupture and cause blood clots that block arteries.

County - A region made up of several cities or towns and includes a local level of government below the state. In Massachusetts, there are 14 counties: Barnstable, Berkshire, Bristol, Dukes, Essex, Franklin, Hamden, Hampshire, Middlesex, Nantucket, Norfolk, Plymouth, Suffolk and Worcester. To identify your county in Massachusetts, please see the Map of Massachusetts Counties or the Community Identification List .

Criteria - Descriptive factors taken into account by U.S. EPA in setting water quality standards for various pollutants for the protection of aquatic life and human health. These factors are used to determine limits on allowable concentration levels, and to limit the number of violations per year. The U.S. EPA also provides guidance to the states on how to establish or adopt water quality standards.

Criteria Pollutants - The 1970 amendments to the Clean Air Act required U.S. EPA to set national ambient air quality standards (NAAQS) for certain pollutants known to be hazardous to human health. U.S. EPA has identified and set standards to protect human health and welfare for six pollutants: ozone, carbon monoxide, total suspended particulates, sulfur dioxide, lead, and nitrogen oxide. The term, "criteria pollutants" derives from the requirement that U.S. EPA must describe the characteristics and potential health and welfare effects of these pollutants. It is on the basis of these criteria that standards are set or revised.

Crude Rate - A rate (usually expressed as the number of cases per population at risk over a specified time period) that is not age-adjusted.

Curie (Ci) - A unit of measurement used to measure radioactivity. It indicates the level of radioactivity by the amount of decay of the element per second.

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Data - Data are recorded observations made on people, objects, or other things that can be counted, measured, or quantified in some way.

Data Limitations - Specific information related to the quality or completeness of the data that will helps in understanding it correctly.

Data Source - An organization or information system providing data for tracking.

Data Suppression - [see Cell Suppression].

Deciliter (dL) - A metric measure of capacity that is 1/10th of a liter.

Deleading - Work done to remove or cover surfaces or other material known, suspected or assumed to contain dangerous levels of lead. The purpose of deleading work is to protect children from exposure to lead paint in accordance with the Massachusetts Lead Law.   

Developmental Effects - Physical or cognitive effects that develop in the fetus during pregnancy and may be due to exposure before conception (either parent), during fetal development, or may be due to genetics.

Dichlorodiphenyltrichloroethane (DDT) - Was a commonly used pesticide prior to 1972, before it was banned.  Although it is no longer used or produced in the United States, we continue to find DDT in our environment. DDT is a probable human carcinogen, damages the liver, temporarily damages the nervous system, reduces reproductive success, can cause liver cancer, and damages the reproductive system.

Dioxin - Commonly used to refer to a family of toxic chemicals that share a similar chemical structure and induce harm through a similar mechanism. Dioxins have been characterized by EPA as likely human carcinogens and are anticipated to increase the risk of cancer at background levels of exposure.  

Disease Registry - A system of ongoing registration of all cases of a particular disease or health condition in a defined population.

Disinfectant - A chemical (commonly chlorine, chloramine, or ozone) or physical process (e.g., ultraviolet light) that inactivates microorganisms such as bacteria, viruses, and protozoa.

Disinfection Byproducts (DBPs) - Disinfection byproducts form when disinfectants used to treat drinking water react with naturally occurring materials in the water (e.g., decomposing plant material). U.S. EPA regulates two classes of DBPs: total trihalomethanes (TTHM) and five haloacetic acids (HAA5). The presence of TTHM and HAA5 is representative of the occurrence of many other chlorination DBPs; thus, a reduction in the TTHM and HAA5 generally indicates a reduction of DBPs from chlorination. DBPs in drinking water can change from day to day, depending on the season, water temperature, amount of disinfectant added, the amount of plant material in the water, and a variety of other factors.

Disposal Site - The name given to contaminated properties regulated under Massachusetts General Law, Chapter 21E, the state Superfund law. This law was originally enacted in 1983 (and amended in 1992, 1995, and 1998) and it created the state’s waste site cleanup program. Disposal sites are often called “21E sites”. The regulations adopted to implement Chapter 21E are called the Massachusetts Contingency Plan (MCP) [see Tier Classification].

DOD - United States Department of Defense.

DOE - United States Department of Energy. May also refer to the previous name of the Massachusetts Department of Elementary and Secondary Education.

Down Syndrome - [see Trisomy 21].

Drinking Water Compliance - The act of meeting all state and federal drinking water regulations.

Drinking Water Contaminant - Any physical chemical, biological, or radiological substance or matter in drinking water.

Drinking Water Exemption - State or U.S. EPA permission for a water system not to meet a certain drinking water standard. An exemption allows a system additional time to obtain financial assistance or make improvements in order to come into compliance with the standard. The system must prove that (1) there are compelling reasons (including economic factors) why a Maximum Contaminant Level or Treatment Technique cannot be met (2) the system was in operation on the effective date of the requirement and (3) the exemption will not create an unreasonable risk to public health. The state must set a schedule under which the water system will comply with the standard for which it received an exemption.

Drinking Water Monitoring - Testing that water systems must perform to detect and measure contaminants. A water system that does not follow U.S. EPA's monitoring methodology or schedule is in violation and may be subject to legal action.

Drinking Water Supply - Water available for drinking.

Drinking Water Supply Distribution System - A network of pipes used to carry treated water from the treatment plant to customers' plumbing systems.

Drinking Water Treatment Technique - A required process intended to reduce the level of a contaminant in drinking water.

Drinking Water Variance - State or U.S. EPA permission not to meet a certain drinking water standard. The water system must prove that (1) even while using the best available treatment method it cannot meet a Maximum Contaminant Level because of the characteristics of the raw water and (2) the variance will not create an unreasonable risk to public health. The state or U.S. EPA must review and allow public comment on a variance every three years. States can also grant variances to water systems that serve small populations and which prove that they are unable to afford the required treatment or an alternative water source or to otherwise comply with the standard.

Drinking Water Violations - A failure to meet any state or federal drinking water regulation.

Dust - Dry particles in the air that range in diameter from 10 to 50 microns. In outdoor air, a wide range of sources contribute to PM10 including road traffic, construction work, mineral extraction, wind-blown soil, and pollen. Lead dust is one of the most common ways that people are exposed to lead. Inside the home, most lead dust comes from chipping and flaking paint or when paint is scraped, sanded, or disturbed during home remodeling.   

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Ecologic Linkage - In epidemiology, a relationship based on co-location in time and place. Analysis occurs at the group rather than individual level.

Elevated Blood Lead Level (EBLL) - For the MA EPHT and Childhood Lead Poisoning Prevention Programs, blood lead levels equal to or greater than 10 µg/dL are defined as EBLLs. Levels equal to or greater than 25 µg/dL currently define a child as poisoned.

Emergency Department (ED) - The department of a hospital or a health care facility off the premises of a hospital that is listed on the license of a hospital to provide emergency services.

Emergency Preparedness Regional Coalition (EP Regional Coalition) - The MDPH Emergency Preparedness Regional Coalitions are areas comprised of contiguous communities used by MDPH for statistical, care coordination, and administrative purposes. These regions belong to larger Emergency Preparedness Regions and were defined by the MDPH Emergency Preparedness Bureau. To identify your EP Region in Massachusetts, please see the Massachusetts Emergency Preparedness Regional Coalitions Map or the Community Identification List.

Endocrine - Relating to the parts of the body which secrete hormones, such as the thyroid and adrenal glands.

Endocrine Disruptors – Chemical substances that interfere with the synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body that are responsible for the maintenance of homeostasis (normal cell metabolism), reproduction, development, and/or behavior.

Enrollment - Number of students attending a particular school, district or collaborative.

Environment - The sum of all external conditions affecting the life, development, and survival of an organism.

Environmental Exposure - Human exposure to pollutants or radiation. Threshold levels are not necessarily surpassed. Low-level chronic pollutant exposure is one of the most common forms of environmental exposure [see Threshold Level].

Environmental Hazard - A substance or situation in the environment that might adversely affect human health. People can be exposed to physical, chemical, or biological toxins from various environmental sources through air, water, soil, and food.

Environmental Health - The branch of public health that is concerned with understanding how the environment affects human health. The environment is the air we breathe, our water, our surroundings, and our food that includes the chemical, physical, and biological toxins that have contact with us everyday.

Environmental Justice - The fair treatment and meaningful involvement of all people regardless of race, national origin, color, or income when developing, implementing, and enforcing environmental laws, regulations, and policies. Fair treatment means that no group of people, including a racial, ethnic, or socioeconomic group, should bear more than its share of negative environmental impacts.

Environmental Monitoring - [see Monitoring].

Environmental Media - Soil, water, air, biota (plants and animals), or any other parts of the environment that can contain contaminants.

EPA - United States Environmental Protection Agency [see U.S. EPA].

U.S. EPA Health Advisory (Water) - A U.S. EPA document that provides guidance and information on contaminants that can affect human health and that may occur in drinking water, but which U.S. EPA does not currently regulate in drinking water.

Environmental Public Health - Focuses on the relationships between people and their environment, promotes human health and well-being, and fosters a safe and healthful environment.

Environmental Public Health Tracking -Environmental Public Health Tracking is the ongoing, systematic collection, integration, analysis, interpretation, and dissemination of data from environmental hazard monitoring, and from human exposure and health effects surveillance.

Environmental Tobacco Smoke -Secondhand smoke or tobacco smoke inhaled by someone who is in close proximity to a smoker.

EOHHS Region (Executive Office of Health & Human Services Region) - The EOHHS Regions are areas comprised of contiguous communities created for statistical, care coordination, and administrative purposes. These regions were defined by the Commonwealth’s Executive Office of Health & Human Services. To identify your EOHHS region in Massachusetts, please see the Massachusetts Executive Office of Health and Human Services Regions Map or the Community Identification List.

Epidemiologic Surveillance - [see Public Health Surveillance].

Epidemiology - The study of the distribution and determinants of disease or health status in a population; the study of the occurrence and causes of health effects in humans.

Ethnicity - A term that represents a group based on their cultural and social affiliation, common history and origin, and sense of identification with the group [compare with Race].

Exacerbation - Any worsening of a disease or condition such as asthma. Onset can be acute and sudden, or gradual over several days. In asthma, a correlation between symptoms and peak flow is not necessarily found.

Exceedance - Violation of the pollutant levels permitted by environmental protection standards.

Expected Diagnoses - The number of individuals expected to be diagnosed with a particular disease if the community or census tract has the same disease experience as the state after adjusting for the population size and the age distribution of the population.

Exposure - The amount of radiation or pollutant present in a given environment that represents a potential health threat to living organisms. Contact with a substance may be by swallowing, breathing, or touching the skin or eyes. Exposure may be short-term (acute exposure), of intermediate duration, or long-term (chronic exposure).

Exposure Assessment - The process of finding out how people come into contact with a hazardous substance, how often and how long they are in contact with the substance, and how much of the substance they are in contact with.  

Exposure Investigation - The collection and analysis of site-specific information and biologic tests (when appropriate) to determine whether people have been exposed to hazardous substances.

Exposure Pathway - The route a substance takes from its source (where it began) to its end point (where it ends), and how people can come into contact with (or get exposed to) it. An exposure pathway has five parts: a source of contamination (such as a leaking underground storage tank); an environmental media and transport mechanism (such as movement through groundwater); a point of exposure (such as a private well); a route of exposure (eating, drinking, breathing, or touching), and a receptor population (people potentially or actually exposed). When all five parts are present, the exposure pathway is termed a completed exposure pathway.

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Facility or Plant - Means the building or buildings or parts thereof, used for, or in connection with, the preparing, processing, manufacturing, packaging, repackaging, canning, bottling, keeping, exposing, storing, handling, distributing or holding of food.

Family Educational Rights and Privacy Act (FERPA) - A law that protects the privacy of student education records.

FEMA - [see Federal Emergency Management Agency].

Federal Emergency Management Agency (FEMA) - The goal of FEMA is: to work to build, sustain and improve our capability to prepare for, protect against, respond to, recover from and mitigate all hazards.

Fertility - Refers to the ability to have live children.

Finished Water - Water that has been treated and is ready to be delivered to customers.

Fire Related Unintentional Carbon Monoxide (CO) Poisoning – Refers to CO poisoning that occurs from accidental injury caused by fire and flames. The NCDMs for CO poisoning include fire related, non-fire related and unknown causes.  Hospitalizations due to intentional CO poisonings are not included.  Unintentional carbon monoxide poisoning is classified as any primary or other diagnosis code of 986, or cause of injury code E868.2, E868.3, E868.8, E868.9, E982.0, or E982.1. Cases with any intentional cause of carbon monoxide poisoning (E952.0, E952.1) or other intentional injury (E950.0-E979.9, E990.0-E999) anywhere in the record are excluded.

FIRM - [see Flood Insurance Rate Map].

Fish - Means fresh or saltwater finfish, crustaceans, other forms of aquatic animal life (including, but not limited to, alligator, frog, aquatic turtle, jellyfish, sea cucumber, and sea urchin, and the roe of such animals) other than birds or mammals, and all molluscan and non-molluscan shellfish, when such animal is intended for human consumption.

Fishery Product - Means any human food product in which fish is a characterizing ingredient.

Flood Insurance Rate Map (FIRM) - Official map of a community on which the Mitigation Division Administrator has delineated both the special hazard areas and the risk premium zones applicable to the community.

Food - Means all articles whether simple, mixed, or compound, used for food or drink, confectionery or condiment, by man or animal.

Frozen Desserts - Include, but is not limited to, ice cream, frozen custard, gelato, ice milk, sherbet, sorbet, frozen yogurt, water ice, any soy-based frozen dessert, any rice-based frozen dessert, and any other similarly constituted product marketed as a frozen dessert, or frozen dessert products made from the milk of cows, sheep, goats, and other dairy animals.

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Gastroschisis - Congenital opening of the abdominal wall with protrusion of the abdominal contents. Can be distinguished from omphalocele by location usually to the right of the umbilicus (navel or “bellybutton”).

Geographic Information System (GIS) - A mapping system that uses computers to collect, store, manipulate, analyze, and display data. For example, GIS can show the concentration of a contaminant within a community in relation to points of reference such as streets and homes.

Gestation - The period during which a baby grows and develops inside the mother's uterus or womb (about 266 days in humans).

GIS - [see Geographic Information System].

Greenhouse Effect - The warming of the Earth's atmosphere attributed to a buildup of carbon dioxide or other gases. This build-up traps infrared radiation in the Earth’s atmosphere leading to a warming effect.

Greenhouse Gas -A gas, such as carbon dioxide or methane, which contributes to potential climate change.

Groundwater - Water beneath the earth's surface in the spaces between soil particles and between rock surfaces [compare with Surface Water].

Growth retardation - Occurs when the growth of the fetus is abnormally slow.

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HAA5 - The sum of five regulated haloacetic acids (monochloro-, dichloro-, trichloro-, monobromo-, dibromo-). These are a widely occurring class of DBPs formed when water is disinfected with chlorine and chloramine.

Half-life - The time required for the disintegration of one-half of the radioactive atoms of a radionuclide.

Hazard - (1) A source of potential harm from past, current, or future exposures. (2) The inherent toxicity of a compound.

Hazardous Air Pollutants - [see Air Toxics].

Hazardous Substance Release and Health Effects Database (HazDat) - The scientific and administrative database system developed by ATSDR to manage data collection, retrieval, and analysis of site-specific information on hazardous substances, community health concerns, and public health activities.

Hazardous Waste - Potentially harmful substances that have been released or discarded into the environment.

Health Outcome - The disease or health problem, such as asthma or birth defects.

Health Insurance Portability and Accountability Act (HIPAA) - A law requiring protection of personal health information.

Health Investigation - The collection and evaluation of information about the health of community residents. This information is used to describe or count the occurrence of a disease, symptom, or clinical measure and to evaluate the possible association between the occurrence and exposure to hazardous substances.

Health Promotion - The process of enabling people to increase control over and improve their health.

Health Statistics Review - The analysis of existing health information (i.e., from death certificates, birth defects registries, and cancer registries) to determine if there is excess disease in a specific population, geographic area, and time period. A health statistics review is a descriptive epidemiologic study.

Heart Attack - [see Myocardial Infarction].

Heart Disease - Any organic, mechanical, or functional abnormality of the heart; it may be valvular, myocardial, or neurogenic.

Heavy Metals - There are several definitions for "heavy metals". For MA EPHT, a heavy metal is defined as a metallic chemical element that has a relatively high density and is toxic at low concentrations. Heavy metals are natural components of the earths crust. Exposure to heavy metals may occur through diet, the environment, medications, or specific occupations. As trace elements, some heavy metals (e.g. iron, copper, zinc) are essential to the human body. However, even these can cause harm at higher levels.

Herbicide -Chemicals used to control undesirable weeds and plants in agricultural, residential, and water environments.

High Risk Community - A community that because of certain social, geographic and demographic characteristics is more prone to certain illnesses than a community that does not have these characteristics.

Hospitalization - The event of a person being admitted to, receiving care at and being discharged from a hospital after receiving treatment. Treatment as an out-patient is not considered to be a hospitalization.

Hospital Transfers - A patient discharged from one facility and readmitted to a second facility on the same day.

Housing Age - Measured by period in time when a house was built.

Human Health Risk - The likelihood that a given exposure or series of exposures may have damaged or will damage the health of individuals.

Hypertrophy - Overgrowth due to enlargement of existing cells.

Hypoplasia - Small size of organ or part due to arrested development.

Hypoplastic Left Heart Syndrome (HLHS) - Congenital heart defect characterized by extreme smallness of left-sided structures. Classically, aortic valve/mitral valve atresia or marked hypoplasia, ascending aorta and left ventricle hypoplasia.

Hypospadias - Congenital defect of the penis in which the urethral meatus (urinary outlet) is located on the underside of the penis (not on the tip). Severity based on location from shaft to scrotum and perineum.

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ICD-9 - International Classification of Disease, 9th revision; a numbered system for classifying diseases and health conditions that is published by the World Health Organization and used as an international standard for epidemiological and health management purposes.

ICD-10 - International Classification of Disease, 10th revision; published in 1990 as an updated version of ICD-9.

ICDO-3 - International Classification of Diseases for Oncology, 3rd edition. It is the current standard method for coding cancer incidence.

Immunological - The body’s immune system and its defense against infection and certain other diseases.

Incidence - The number of new cases of disease in a defined population over a specific time period [contrast with Prevalence].

Indoor Air Pollution - Air pollutants that occur within buildings or other enclosed spaces, as opposed to those occurring in outdoor or ambient air. Some examples of indoor air pollutants are nitrogen oxides, smoke, asbestos, formaldehyde, and carbon monoxide.

Infant Mortality - Occurs when an infant dies in the first year of life.

Inorganic Contaminants - Mineral-based compounds such as metals, nitrates, and asbestos. These contaminants are naturally-occurring in some water, but can also get into water through farming, chemical manufacturing, and other human activities. U.S. EPA has set legal limits for 15 inorganic contaminants.

Internal Irradiation - Exposure to radiation inside the body. 

International Classification of Diseases (ICD) - A system produced by an internationally representative group that classifies diseases by giving each a unique code.

Interstate Milk Shipper (IMS) Rating - Means the inspection and the evaluation score for a dairy processing plant that sells or distributes the manufactured dairy product in inter-state commerce.

Isotope - A different form of the same element.

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Juice - Means the liquid expressed or extracted from one or more fruits or vegetables, purees of the edible portions of one or more fruits or vegetables, or any concentrates of such liquid or puree.

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Land Use - The human modification of natural environment or wilderness into built environment such as fields, pastures, and settlements.

Lead - A naturally occurring bluish-gray metal found in small amounts in the earth’s crust. Lead can be found in all parts of our environment. Much of it comes from human activities including burning fossil fuels, mining, and manufacturing. In the past, lead was used as an additive in gasoline and paint, however this practice has been discontinued in the United States.

Lead Law - The Massachusetts Lead Law requires that all children be tested for lead between the ages of 9 and 12 months, and again at ages 2 and 3. Additionally, all children should be screened at age 4 if they live in a high risk community in Massachusetts. The Lead Law also requires the deleading or interim control of lead hazards existing in homes built before 1978 where children under six live. Owners are responsible for complying with the Lead Law and paying the costs to delead. This includes owners of rental property as well as owners living in their own single-family or multi-family home.

Lead Poisoning – According to the Massachusetts Lead Law, lead poisoning occurs in a child when the concentration of lead in whole venous blood is 25 micrograms per deciliter (µg/dL) or greater.. Lead poisoning is caused by swallowing or breathing lead and is especially dangerous for young children. Lead poisoning can cause permanent damage to the brain, kidneys and nervous system and lead to learning and behavioral problems.

Limb Deficiency, Upper (arms) / Lower (legs) - Congenital absence of a portion or entire limb. Types include transverse (resembling an amputation), longitudinal (missing ray i.e. missing finger or toe and its related metacarpal or metatarsal bone) and intercalary (missing bone in-between).

Low Birth Weight – A baby is considered to be of low birth weight when its weight is less than 5.5 lbs, or 2500 grams, at birth. For Tracking, low birth weight is measured among singleton births only.

Lower Limb Deficiency - [see Limb Deficiency, Upper (arms) / Lower (legs)].

Leukemia - A type of cancer in the blood or bone marrow. It is characterized by an increase in immature white blood cells.

Lung Cancer - Cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer; they are diagnosed based on how the cells look under a microscope.

Lung Disease - A broad term that refers to many disorders affecting the lungs. Lung disease includes diseases such as asthma, emphysema, and chronic bronchitis.

Lymphoma - Cancer that starts in a part of the immune system called the lymphatic system, which is made up of lymph or lymphatic tissue.

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MA CZM - Massachusetts Office of Coastal Zone Management

Massachusetts Lead Law - [see Lead Law].

Maximum Contaminant Level (MCL) - The maximum permissible level of a contaminant in water which is delivered to any user of a public water system. The MCL is set as close to the Maximum Contaminant Level Goal MCLG as feasible, which the Safe Drinking Water Act defines as the level that may be achieved with the use of the best available technology, treatment techniques, and other means which U.S. EPA finds are available taking cost into consideration.

Maximum Contaminant Level Goal (MCLG) - The maximum level of a contaminant in drinking water at which no known or anticipated adverse effect on the health of persons would occur and which allows an adequate margin of safety. MCLGs are non-enforceable public health goals. Since MCLGs consider only public health and not the limits of detection and treatment technology, sometimes they are set at a level which water systems cannot meet.

Maximum Contaminant Level Violation - Failure to keep a contaminant level in drinking water below its Maximum Contaminant Level.

Mean -Average.

Medical Monitoring - A set of medical tests and physical exams.  

Meat - Means the edible portion of livestock or wild-caught animals after slaughter.

Meat and Poultry Processing (Less or Greater than $10 million in annual sales) - Means the inspection of wholesale meat and poultry processing establishments. In Massachusetts, there are two levels of licensing fees for wholesale meat and poultry processors: those establishments with annual sales less than $10 million, and establishments with annual sales greater than $10 million.

Meat Food Product - Means any article used as human food which is made wholly, or in part, from any meat or other portion of the carcass of any livestock.

Mental Retardation - A condition marked by an intelligence quotient (IQ) of less than or equal to 70 on the most recently administered psychometric test.  In the absence of an IQ score, a written statement by a psychometrist that a child's intellectual functioning falls within the range for mental retardation is acceptable. The severity of mental retardation is defined according to the following International Classification of Disease, Ninth Edition, Clinical Modification (ICD-9-CM) categories: mild (an IQ of 50-70), moderate (an IQ of 35-49), severe (an IQ of 20-34), and profound (an IQ of less than 20).

Metabolism - The set of chemical reactions that happen in living organisms to maintain life.

Metabolite - Any product of metabolism.

Metadata - Metadata is "data about data" that describes the content, quality, and context of a dataset and provides links to additional information such as quality assurance documents and data dictionaries. Both the national and MA EPHT websites contain metadata records for each dataset in the tracking program. 

Metropolitan Area (MA) - The general concept of a metropolitan area (MA) is one of a large population area together with adjacent communities that have a high degree of economic and social integration. Each MA must contain either a place with a minimum population of 50,000 or a U.S. Census Bureau-defined urbanized area with a total Metropolitan Area population of at least 75,000 in New England. In New England, MAs consist of groupings of cities and towns rather than whole counties.

Metropolitan Statistical Area - Metropolitan statistical areas (MSAs) are metropolitan areas (MAs) that are not closely associated with other MAs. These areas typically are surrounded by nonmetropolitan counties (county subdivisions in New England).

Micrograms (µg) - Unit of measure for weight/mass equal to one-millionth of a gram used to measure the concentration of pollutants in the air.

Micrograms per cubic meter (µg/m3) - A unit of measurement associated with the concentration of air pollutants in micrograms (µg or one-millionth of a gram) per cubic meter of air (m3).

Micrometers (µm) - Unit of measure equal to one-millionth of a meter (one-thousandth of a millimeter) used to measure the diameter of particles in air. Also called a micron.

Mobile Sources - Sources of air pollution such as automobiles, motorcycles, trucks, off-road vehicles, boats, and airplanes.

Milk - Means the fluid directly obtained by the complete milking of one or more healthy cows, goats, sheep, or other dairy animals.

Milk-based - Means a product or ingredient derived from milk or a component of milk.

Mobile Poultry Processing - Means "a slaughterhouse on wheels" that travels from farm to farm. The farmers/producers lease the unit to process their own birds on their farm for retail sales.

Monitoring - Environmental testing of air or water to detect and measure contaminants. A water system that does not follow U.S. EPA's monitoring methodology or schedule is in violation, and may be subject to legal action.

Morbidity - The occurrence of a disease or condition that alters health and quality of life; often measured as incidence or prevalence.

Mortality - Death, often measured as a death or mortality rate.

Myocardial Infarction (MI) - Also known as heart attack, acute myocardial infarction, or AMI. It occurs when the heart is without oxygen and the heart muscle dies or becomes permanently damaged.

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Nanometers - Unit of measure equal to one-millionth of a millimeter used to measure diameter of particles in the air.

National Ambient Air Quality Standards (NAAQS) - Standards established by U.S. EPA that apply to outdoor air throughout the country.

National Environmental Public Health Tracking Network - A web-based, secure network of standardized electronic health and environmental data.

National Oil & Hazardous Substances Contingency Plan - A U.S. environmental regulation that guides determination of the sites to be corrected under both the Superfund program and the program to prevent or control spills into surface waters or elsewhere.

National Priorities List for Uncontrolled Hazardous Waste Sites (NPL) - U.S. EPA's list of the most serious uncontrolled or abandoned hazardous waste sites in the United States. The NPL is updated on a regular basis.

Nationally Consistent Data and Measures (NCDM) - NCDMs, or nationally consistent data and measures, are environmental public health indicators that provide information about a populationís health status with respect to environmentally-related factors. They stem from the efforts of grantees and CDC to compile, on a national basis, datasets that are derived from many sources but are standardized to provide consistent reporting across the nation. Initial decisions about the health and environmental data to include on the Network were based on many factors. These factors included giving priority to the needs of state and local health departments as well as priority to the needs of CDC. Also considered was whether data were available for a particular content area. New priority areas have been and will continue to be identified over time.

Neonatal Mortality - An infant death which occurs in the first 27 days of life.

Neural Tube - The developing embryo's precursor to the central nervous system, which comprises the brain and spinal cord.

Neurological - The study of the nervous system and disorders affecting it.

95% Confidence Interval (CI) - [see Confidence Interval].

Nitrates - Nitrates are compounds of nitrogen and oxygen. The major source is found in food but high levels of nitrates can be found in drinking water due to sources such as septic tanks and fertilizer run-off. Once taken into the body, nitrates are converted into nitrites. High nitrate levels in drinking water can be a risk to infants. Nitrites can pose a risk to children and adults.

Nitric Oxide (NO) - A gas formed by combustion under high temperature and high pressure in an internal combustion engine; it is converted by sunlight and photochemical processes in ambient air to nitrogen oxide. NO is a precursor of ground-level ozone pollution, or smog.

Nitrogen Dioxide (NO2) - The result of nitric oxide combining with oxygen in the atmosphere; major component of photochemical smog.

Nitrogen Oxide (NOx) - The result of photochemical reactions of nitric oxide in ambient air; major component of photochemical smog. Product of combustion from transportation and stationary sources and a major contributor to the formation of acid rain and ozone in the atmosphere.

Non-attainment Area - Area that does not meet one or more of the National Ambient Air Quality Standards (NAAQS) for the criteria pollutants designated in the Clean Air Act.

Non-fire Related Unintentional Carbon Monoxide (CO) Poisoning – Refers to CO poisoning that occurs from accidental injury that is not caused by fire and flames.   The NCDMs for CO poisoning include fire-related, non-fire-related and unknown causes. Hospitalizations due to intentional CO poisoning are not included. .  The non-fire related unintentional CO poisoning cases encompass the following ICD9 discharge diagnosis codes E800.0-E848.9, E850-E869.9, E880-E888.9 and E900-E928.9 and ICD10 diagnosis codes of  V01 – W99, X10-X59, and Y85-Y86.

Non-Hodgkin Lymphoma - Any of a large group of cancers of the immune system. Non-Hodgkin lymphoma begins when a type of white blood cell either T- or B-cells, become abnormal. The cells then divide again and again, producing more abnormal cells. These cancers are often marked by enlarged lymph nodes, fever, and weight loss.

Non-Transient, Non-Community Water System (NTNC) - A water system which supplies water to 25 or more of the same people at least six months per year in places other than their residences. Some examples are schools, factories, office buildings, and hospitals which have their own water systems.

NPL - [see National Priorities List for Uncontrolled Hazardous Waste Sites].

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Observed Diagnoses - The number of individuals diagnosed with a disease in a given geographic area and time period.

Omphalocele - Congenital opening of the abdominal wall with protrusion of the abdominal contents. Can be distinguished from gastroschisis by its location at the site of the umbilicus (navel or “bellybutton”).

Organic Compounds - Compounds that contain carbon.

Organic Contaminants - Carbon-based chemicals, such as solvents and pesticides, which can get into water, air or soil through runoff from cropland or discharge from factories.

Organic Matter - The matter that has come from a once-living organism; is capable of decay, or the product of decay; or is composed of organic compounds (molecules that contain carbon).

Organic Water Contaminants - Carbon-based chemicals, such as solvents and pesticides, which can get into water through runoff from cropland or discharge from factories.

Ozone (O3) - There are two types of ozone—“good” ozone and “bad”, ground-level ozone. Bad ozone is an odorless, colorless gas that is created by a chemical reaction and can affect health.

Ozone Layer - The protective layer in the atmosphere, about 15 miles above the ground, which absorbs some of the sun’s ultraviolet rays, thereby reducing the amount of potentially harmful radiation that reaches the earth's surface.

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Particle Count - Results of a microscopic examination of treated water with a special "particle counter" that classifies suspended particles by number and size.

Particle Pollution - A complex mixture of extremely small particles and liquid droplets. Particle pollution is made up of a number of components, including acids, such as nitrates and sulfates, organic chemicals, metals, and soil or dust particles.

Particulate Matter (PM) - "Particles" or "particulate matter" are terms used to describe the mixture of solid particles and liquid droplets in the atmosphere. The microscopic solid and liquid particles are of human and natural origin and can vary greatly in size, composition, and origin, and may be potentially harmful. [see PM2.5 and PM10].

Pasteurization Plant - Means an establishment for the pasteurization of milk.

Peak Levels - A level of airborne pollutants that is much higher than average. They can occur over a short period of minutes or hours in response to sudden releases, or they can occur due to a longer term build-up over several days.

Pediatric Asthma Tracking - The ongoing collection, analysis, and interpretation of health data from schools where children are enrolled in Kindergarten through 8th grade and had been diagnosed with asthma.

Perinatal Mortality - A fetal death after 28 or more weeks gestation and an infant death within the first 6 days of life.

Pesticide - Any substance or mixture of substances intended for preventing, destroying, repelling, or controlling any pest: herbicides, fungicides, insecticides, and various other substances.

Phthalates - Group of chemicals that are generally used as plasticizers (substances added to plastics to increase their flexibility, transparency, durability, and longevity).  Phthalates are considered endocrine disruptors and may cause birth defects and fetal death.

Placental Abruption - Placental abruption (abruptio placentae) is an uncommon yet serious complication of pregnancy. The placenta is a structure that develops in the uterus during pregnancy to nourish the growing baby. If the placenta peels away from the inner wall of the uterus before delivery — either partially or completely — it's known as placental abruption. Placental abruption can deprive the baby of oxygen and nutrients and cause heavy bleeding in the mother.

Placenta Previa - The placenta provides oxygen and nutrients to your growing baby and removes waste products from your baby's blood.  Placenta previa occurs when a baby's placenta partially or totally covers the mother's cervix — the doorway between the uterus and the vagina. Placenta previa can cause severe bleeding before or during delivery.

PM2.5 - Particulate matter with an aerodynamic diameter of up to 2.5 µm, referred to as the fine particle fraction (per definition includes the ultrafine particles, which are <0.1 µm in size).

PM10- Particulate matter with an aerodynamic diameter of up to 10 µm, i.e. the fine and coarse particle fractions combined.

Point of Exposure - The place where someone can come into contact with a substance present in the environment [see Exposure Pathway].

Point Sources - Specific points of origin where air pollutants are emitted into the atmosphere such as factory smokestacks.

Pollutant - Generally, any substance introduced into the environment that adversely affects the usefulness of a resource or the health of humans, animals, or ecosystems.

Pollution - Generally, the presence of a substance in the environment that because of its chemical composition or quantity prevents the functioning of natural processes and produces undesirable environmental and health effects. Under the Clean Water Act, for example, the term has been defined as the man-made or man-induced alteration of the physical, biological, chemical, and radiological integrity of water and other media.

Population - A group or number of people living within a specified area or sharing similar characteristics (such as occupation or age).

Polychlorinated Biphenyls (PCBs) - Belong to a broad family of man-made organic chemicals known as chlorinated hydrocarbons. PCBs have been demonstrated to cause cancer, as well as a variety of other adverse health effects on the immune system, reproductive system, nervous system, and endocrine system.

Polycyclic Aromatic Hydrocarbons (PAHs) – A group of chemicals that are formed during the incomplete burning of coal, oil, gas, wood, garbage, or other organic substances, such as tobacco and charbroiled meat. There are more than 100 different PAHs. PAHs generally occur as complex mixtures (for example, as part of combustion products such as soot), not as single compounds.  Many PAHs are carcinogenic.

Population at Risk - A population subgroup that is more likely to be exposed to a chemical, or is more sensitive to the chemical, than the general population.

Postneonatal Mortality – An infant death which occurs between 28 days and a year of life.

Poverty Percent or Rate - The percentage of people or families who are below poverty (12% – 15% below federal poverty line).

PPB - Parts per billion; denotes 1 part per 1,000,000,000 parts.

Poultry - Means any bird, whether live or dead, intended for use as food.

Poultry Food Product - Means any product capable of use as human food which is made wholly, or in part, from any poultry carcass or part.

PPM - Parts per million; denotes 1 part per 1,000,000 parts.

Premature Births - The occurrence of a birth at least 3 weeks before the scheduled due date.  Prematurity is also known as preterm or very preterm birth.

Prenatal - Occurring or existing before birth.

Preterm Birth - The birth of an infant less than 37 weeks gestation.  For Tracking, preterm births are measured among singleton births only.  Also known as premature birth.

Prevalence - The proportion of individuals in a population having a disease or condition. Prevalence is a statistic that refers to the number of cases of a disease that are present in a particular population at a given time. Asthma prevalence is the number of children with asthma divided by the total number of children in the population multiplied by 100. Childhood lead poisoning prevalence is the number or proportion of children with a specific blood lead level out of the total number of children screened. Prevalence for the number of children with a particular measured blood lead level in a population is usually presented as the prevalence per 1000 population.

Prevalence Survey - The measure of the current level of disease(s), symptoms, and/or exposures identified through a questionnaire that collects self-reported information from a defined population.

Prevention - Proactive activities conducted to avoid health hazards and their consequences.

Primacy State - A state that has the responsibility and authority to administer U.S. EPA's drinking water regulations within its borders. The state must have rules at least as stringent as U.S. EPA's.

Primary Metropolitan Statistical Area (PMSA) - If an area that qualifies as a metropolitan area (MA) has more than one million people, two or more primary metropolitan statistical areas (PMSAs) may be defined within it. Each PMSA consists of a large urbanized county or cluster of counties (cities and towns in New England) that demonstrate very strong internal economic and social links, in addition to close ties to other portions of the larger area [see Metropolitan Area (MA) and Metropolitan Statistical Area (MSA)].

Primary Prevention - Proactive activities conducted to avoid health hazards and their consequences. Preventing a problem before it occurs. Primary prevention of lead poisoning would eliminate lead sources, thus preventing exposure.

Privacy - Health information privacy broadly refers to individuals’ rights to control the acquisition, use, or disclosure of their identifiable health data.

Private School - Private schools, including parochial schools that operate independently of state or regional authority. Some aspects of these programs, such as those involving students with disabilities, are subject to regulation under state law.

Public Health Advisory - A statement made by ATSDR to U.S. EPA or a state regulatory agency that a release of hazardous substances poses an immediate threat to human health. The advisory includes recommended measures to reduce exposure and reduce the threat to human health.

Public Health Assessment (PHA) - An ATSDR document that examines hazardous substances, health outcomes, and community concerns at a hazardous waste site to determine whether people could be harmed from coming into contact with those substances. The PHA also lists actions that need to be taken to protect public health.

Public Health Hazard - A category used in ATSDR's public health assessments for sites that pose a public health hazard because of long-term exposures (greater than 1 year) to sufficiently high levels of hazardous substances or radionuclides that could result in harmful health effects.

Public Health Hazard Categories - Public health hazard categories are statements about whether people could be harmed by conditions present at the site in the past, present, or future. One or more hazard categories might be appropriate for each site. The five public health hazard categories are no public health hazard, no apparent public health hazard, indeterminate public health hazard, public health hazard, and urgent public health hazard.

Public Health Surveillance - The ongoing, systematic collection, analysis, and interpretation of health data. This activity also involves timely dissemination of the data and use for public health programs.

Public School District - A public school district consists of one or more public schools operated under the supervision of an elected or appointed school committee and a superintendent. The majority of school districts serve a single city or town, and are considered a department of the municipal government. Two or more municipalities can also join together to form a regional school district, which is considered a separate and independent unit of local government. A regional school district can offer all grades (preK-12), just certain grades (for example, just elementary grades or just high school), or just certain types of instruction (for example, vocational and technical programs).

Public Water System (PWS) - Any water system that provides water for human consumption through pipes or other constructed conveyances to at least 15 service connections or serves an average of at least 25 people for at least 60 days a year.  Also known as Community Water System (CWS)

Pulmonary - Relating to or affecting the lungs.

Pulmonary Valve Stenosis - Congenital heart defect characterized by narrowing of the pulmonary valve resulting in reduced blood flow to the lungs.

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Race - The classification of humans into populations or groups on the basis of various sets of characteristics. The most commonly used categories are based on visible traits, such as skin color, facial features, hair texture, and self-identification [compare with Ethnicity].

Radionuclide - Radioactive particle, man-made or natural. Can have a long life as a soil or water pollutant.

Radon - A cancer-causing radioactive gas that cannot be smelled, tasted, or seen and that comes from the decay of radium.

Rate - A measure of the frequency with which an event occurs in a defined population.

Receptor Population - People who could come into contact with hazardous substances.

Repeat Hospitalizations - Having more than one hospital discharge (within a specified time frame) for treatment of the same health condition.

Reproductive - The biological process by which new individual organisms are produced.

Residential Kitchen - Means a kitchen in a private home that processes food for sale at wholesale.

Respiratory - Relating to or affecting breathing or the organs used to breathe.

Respiratory Distress Syndrome (RDS) - Respiratory distress syndrome (RDS) is a breathing disorder that affects newborns. The disorder is more common in premature infants born about 6 weeks or more before their due dates.  RDS is more common in premature infants because their lungs aren't able to make enough surfactant. Surfactant is a liquid that coats the inside of the lungs. It helps keep them open so that infants can breathe in air once they're born.  Without enough surfactant, the lungs collapse and the infant has to work hard to breathe. He or she might not be able to breathe in enough oxygen to support the body's organs. The lack of oxygen can damage the baby's brain and other organs if proper treatment isn't given.

Risk Communication - The exchange of information about health or environmental risks among risk assessors and managers, the general public, news media, interest groups, etc.

Risk Factor - Characteristics (e.g., race, gender, age, obesity) or variables (e.g., smoking, occupational exposure level) associated with increased probability of a toxic effect. A risk factor may be inherited, associated with a lifestyle, or be due to an environmental exposure.

Route of Exposure - The way people come into contact with a hazardous substance. Three routes of exposure are breathing (inhalation), eating or drinking (ingestion), or contact with the skin (dermal contact).

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Sampling Frequency - The interval between the collection of successive samples.

School Year - In Massachusetts, the school year begins in August or September and ends in June.

Screening Rate - For lead levels, the percentage of children ages 9-47 months that were tested for blood lead.   

Screening Test for Lead Poisoning - A laboratory test for lead that is performed on the blood of a child to determine whether the child has an elevated blood lead level (BLL).

SDWA (Safe Drinking Water Act) - passed by Congress in 1974 to protect public health by regulating the nation's public drinking water system. SDWA authorizes the United States Environmental Protection Agency (U.S. EPA) to set national health-based standards for drinking water to protect against both naturally-occurring and man-made contaminants that may be found in drinking water. U.S. EPA, states, and water systems work together to make sure that these standards are met.

Seafood - Means all fish and/or fishery products.

Secondary Prevention - Responding to a problem after it has been detected. Secondary prevention of lead poisoning involves identifying children with elevated blood lead levels (EBLLs) and eliminating or reducing their lead exposure.

Secondhand Smoke - Secondhand smoke comes from both the smoke that smokers exhale (called mainstream smoke) and the smoke floating from the end of the cigarette, cigar, or pipe (called sidestream smoke).  It may seem pretty harmless, but secondhand smoke actually contains thousands of chemicals — from arsenic and ammonia to hydrogen cyanide — many of which have been proven to be toxic or to cause cancer (called carcinogens). High concentrations of many of these chemicals are found in secondhand smoke. In fact, secondhand smoke significantly increases a person's risk for respiratory infections (like bronchitis and pneumonia), asthma (secondhand smoke is a risk factor for the development of asthma and can trigger attacks in those who already have it), coughing, sore throats, sniffling, and sneezing, cancer, and heart disease.

Sell - Means to sell, offer or expose for sale, barter, trade, deliver, give away, possess with intent to sell, or dispose of in any other commercial manner.

Sex Ratio at Birth - The ratio of male to female births.

Sexually Transmitted Diseases (STDs) - Infections acquired by sexual contact.

Shellfish (Molluscan) - Means, whether alive or shucked, all species of:

    (1) Oysters, clams, or mussels, whether:
    • Shucked or in the shell
    • Raw, including post-harvest processed
    • Frozen or unfrozen
    • Whole or in part
    (2) Scallops in any form, except when the final product form is the adductor muscle only.

This term does not include: crustaceans, conch, whelk, snails, periwinkles and shrimp.

Significance - [see Statistical Significance].

SIR - [see Standardized Incidence Ratio].

SSR (Single-Service Rating) - Means an inspection of a facility that manufactures plastics (caps, bottles, containers, or closures) for the storage of milk or milk products.

Smog - A mixture of air pollutants which includes particulates, nitrogen oxides, ozone, etc. Smog often has a brown haze due to the presence of nitrogen dioxide. 

Smoke - Smoke is created when air combines with the airborne solid and liquid particulates and gases that are emitted when a material undergoes combustion.

Soil - The top layer of the earth's surface, consisting of rock and mineral particles mixed with organic matter.

Solder - A metal alloy that is used to fuse together metal pieces and may contain lead.

Sole Source Aquifer - An aquifer that supplies 50 percent or more of the drinking water of an area.

Solvent - A material used to dissolve or dilute another substance.

Source of Contamination - The place where a hazardous substance comes from, such as a landfill, waste pond, incinerator, storage tank, or drum. A source of contamination is the first part of an exposure pathway.

Source Water - Water in its natural state, prior to any treatment for drinking.

Special Populations - People who might be more sensitive or susceptible to exposure to hazardous substances because of factors such as age, occupation, gender, or behaviors (for example, cigarette smoking). Children, pregnant women, and older people are often considered special populations.

Spina Bifida - Neural tube defect with protrusion of the spinal cord and/or meninges (the membranes that cover the brain and spinal cord). Includes myelomeningocele (involving both spinal cord and meninges) and meningocele (involving just the meninges).

Stakeholder - A person, group, or community who has an interest in activities at a hazardous waste site.

Standard Deviation - The standard deviation quantifies how much the values vary from each other. It is calculated by taking the square root of the variance. The more widely the values are spread out or different, the larger the standard deviation.

Standardization - Data standardization is the process of statistically adjusting data from two or more populations so that they may be compared to understand differences between the populations.

Standardized Incidence Ratio (SIR) - An SIR is the ratio of the observed number of cancer diagnoses in an area to the expected number of diagnoses multiplied by 100. Age-specific statewide incidence rates are applied to the population distribution of a community to calculate the number of expected cancer diagnoses. The SIR is a comparison of the number of diagnoses in the specific area (i.e., community or census tract) to the number of expected diagnoses based on the statewide rate. Comparison of SIRs between communities or census tracts is not possible because these areas have different population characteristics (including age distributions). 

Standards - Regulations that impose limits on the amount of pollutants or emissions produced. U.S. EPA establishes minimum standards, but states are allowed to be stricter.

Stationary Sources - Non-mobile sources such as power plants, refineries, and manufacturing facilities which emit air pollutants.

Statistical Significance - The likelihood that the difference found between groups was not due to chance alone. Statistical significance can be based on the use of statistical tests and comparison of confidence intervals. Overlapping confidence intervals indicate that any difference in the screening or prevalence observed may be due to chance. Confidence intervals that do not overlap are considered statistically significant and indicate a small likelihood that the difference is due to chance. 

Statistics - A branch of mathematics that deals with collecting, reviewing, summarizing, and interpreting data or information. Statistics are used to determine whether differences between study groups are meaningful.

Stratosphere - The portion of the atmosphere 10 to 25 miles above the earth’s surface.

Stroke - The sudden death of brain cells due to a lack of oxygen caused by impaired blood flow to the brain, usually from a blockage or rupture of an artery to the brain. A stroke is also called a cerebrovascular accident or CV.

Substance - A chemical.

Substance-specific Applied Research - A program of research designed to fill important data needs for specific hazardous substances identified in ATSDR's toxicological profiles. Filling these data needs will allow more accurate assessment of human risks from specific substances contaminating the environment. This research might include human studies or laboratory experiments to determine health effects resulting from exposure to a given hazardous substance.

Sudden Infant Death Syndrome (SIDS) - Sudden infant death syndrome (SIDS) is the unexplained death, usually during sleep, of a seemingly healthy baby. Sudden infant death syndrome is sometimes called crib death. The exact cause is unknown, but SIDS may be associated with abnormalities in the portion of an infant's brain that controls breathing and arousal from sleep. Although all babies are vulnerable, certain sleep environments have been linked to increased risk. Perhaps the most important way to reduce the risk of sudden infant death syndrome is to place your baby on his or her back to sleep, on a firm crib mattress covered by a fitted sheet. Nothing else should go in the crib with your baby ó no blanket, pillow, bumper pads or toys.

Sulfur Dioxide (SO2) - A pungent, colorless, gas formed primarily by the combustion of fossil fuels; becomes a pollutant when present in large amounts.

Superfund - [see Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and Superfund Amendments and Reauthorization Act (SARA)].

Superfund Amendments and Reauthorization Act (SARA) - In 1986, SARA amended the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and expanded the health-related responsibilities of ATSDR. CERCLA and SARA direct ATSDR to look into the health effects from substance exposures at hazardous waste sites and to perform activities including health education, health studies, surveillance, health consultations, and toxicological profiles.

Surface Water - Water on the surface of the earth, such as in lakes, rivers, streams, ponds, and springs [compare with Groundwater].

Surveillance - The ongoing systematic collection, analysis, and interpretation of health data, essential to the planning, implementation, and evaluation of public health practice, closely integrated with the timely dissemination of these data to those who need to know [see Public Health Surveillance].

Survey - A systematic collection of information or data. A survey can be conducted to collect information from a group of people or from the environment. Surveys of a group of people can be conducted by telephone, by mail, or in person. Some surveys are done by interviewing a group of people [see Prevalence Survey].

Symptom - Any subjective evidence (e.g. anxiety, pain, fatigue) only the patient can perceive. In contrast, a sign is objective evidence of disease. Swelling, bleeding or bruising are signs evident to the patient, doctor, nurse and other observers.

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Test - Any blood test sample that produces a quantifiable result and is analyzed by a certified clinical laboratory.

Test Date - The date the blood test was performed.

Tetralogy of Fallot (TOF) - Congenital heart defect composed of ventricular septal defect, pulmonary stenosis or atresia, displacement of the aorta to the right, and hypertrophy of right ventricle.

Threshold Level -Time-weighted average pollutant concentration values, exposure beyond which is likely to adversely affect human health.

Thyroid Cancer - Cancer that forms in the thyroid gland, a butterfly-shaped organ at the base of the throat that makes hormones that help control heart rate, blood pressure, body temperature, and weight. Four main types of thyroid cancer are papillary, follicular, medullary, and anaplastic thyroid cancer.

Tier Classification - A system developed by the Massachusetts Department of Environmental Protection (MassDEP) to categorize the release of oil and hazardous materials at disposal sites in Massachusetts. Releases of oil and/or hazardous materials are reported to the MassDEP Bureau of Waste Site Cleanup (BWSC), according to procedures established in the Massachusetts Contingency Plan (310 CMR 40.0000). A site’s Tier Classification determines the level of MassDEP oversight. The classification scheme is based on the disposal site's complexity, the type of contamination, and the potential for human or environmental exposure to the contamination. Some sites are automatically classified as Tier 1 sites if they pose an imminent hazard, affect public water supplies, or miss regulatory deadlines. The MassDEP Tier Classified Oil and/or Hazardous Material Sites data layer, accessible when calculating cancer rates, is a statewide point dataset containing the approximate location of disposal sites that have been tier classified under the MCP; sites that have not yet been tier classified are not contained in this data layer [see Disposal Site].

Total Fertility Rate (TFR) - Indicates the average number of births to a hypothetical cohort of 1,000 women if they experienced the age-specific birth rates observed in a given year.

Total Suspended Particulate (TSP) - Particles of solid or liquid matter -- such as soot, dust, aerosols, fumes, and mist up to approximately 30 microns in size. In 1986, the U.S. EPA TSP standard was changed to PM10.

Toxic Agent - Chemical or physical (for example, radiation, heat, cold, microwaves) agents that, under certain circumstances of exposure, can cause harmful effects to living organisms.

Toxicity - The degree to which a substance is able to harm a living organism.

Toxicological Profile - An ATSDR document that examines, summarizes, and interprets information about a hazardous substance to determine harmful levels of exposure and associated health effects. A toxicological profile also identifies significant gaps in knowledge on the substance and describes areas where further research is needed.

Toxicology - The study of the harmful effects of substances on humans, animals, or other living organisms.

Toxic Pollutants - Materials that cause death, disease, or birth defects in organisms that ingest or absorb them. The quantities and exposures necessary to cause these effects can vary widely.

Tracking - [see Environmental Public Health Tracking].

Transient, Non-Community Water System (TNC) - A water system which provides water in a place such as a gas station or campground where people do not remain for long periods of time. These systems do not have to test or treat their water for contaminants which pose long-term health risks because fewer than 25 people drink the water over a long period. They still must test their water for microbes and several chemicals.  

Transport Mechanism - Mechanisms that move contaminants from the source to points where human exposure can occur. The environmental media and transport mechanism is the second part of an exposure pathway.

Transposition of the Great Arteries - Congenital heart defect in which the aorta arises from the right ventricle, and the pulmonary artery arises from the left ventricle (opposite of normal).

Trigger - A risk factor that causes exacerbation of asthma; a stimulus that causes an increase in asthma symptoms and/or airflow limitation.

Trisomy 21 (Down syndrome) - Distinctive and common chromosome abnormality syndrome caused by an extra copy of chromosome 21. The extra chromosome can be present in every cell or complete (Trisomy 21), attached to another chromosome (translocation), or mixed with cells containing normal chromosomes (mosaic).

TTHM - Total trihalomethanes are a widely occurring class of Disinfection Byproducts (see Disinfection Byproducts) that include chloroform, bromoform, bromodichloromethane, and dibromochloromethane.

Tumor - An abnormal mass of tissue that results from excessive cell division that is uncontrolled and progressive. Tumors perform no useful body function. Tumors can be either benign (not cancer) or malignant (cancer).

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Umbilical Cord Prolapse - The umbilical cord is a flexible, tube-like structure that, during pregnancy, connects the fetus to the mother. The umbilical cord is the baby’s lifeline to the mother. It transports nutrients to the baby and also carries away the baby’s waste products. It is made up of three blood vessels – two arteries and one vein.  Umbilical cord prolapse is a complication that occurs prior to or during delivery of the baby. In a prolapse, the umbilical cord drops (prolapses) through the open cervix into the vagina ahead of the baby. The cord can then become trapped against the baby’s body during delivery. Umbilical cord prolapse occurs in approximately one in every 300 births.

Unknown Unintentional Carbon Monoxide (CO) Poisoning – Refers to accidental (unintentional) injury that cannot otherwise be classified as being related to fire or non-fire causes and which encompasses the following ICD10 diagnosis codes of Y10-Y34.

Upper Limb Deficiency - [see Limb Deficiency, Upper (arms) / Lower (legs)].

U.S. Centers for Disease Control & Prevention (CDC) - [see CDC].

U.S. Environmental Protection Agency (U.S. EPA) - An independent federal agency established to coordinate programs aimed at reducing pollution and protecting the environment.

U.S. EPA Air Quality System (AQS) - A database containing measurements of air pollutant concentrations in the 50 states, plus the District of Columbia, Puerto Rico, and the Virgin Islands. The measurements include both criteria air pollutants and hazardous air pollutants.

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Vending - Means a machine that dispenses items such as snacks, beverages, candy, bottled water, and other food items, after the customer inserts currency or credit into the machine.

Venous - Type of testing for blood lead that involves the drawing of blood from a vein rather than a capillary.

Ventricle - Either of the two lower chambers of the heart.

Ventricular Septal Defect - Congenital defect characterized by one or several openings in the septum (wall) dividing the left and right ventricles of the heart.

Very Low Birth Weight - A baby is considered to be of low birth weight when its weight is less than 3.3 lbs, or 1,500 grams, at birth. For Tracking, low birth weight is measured among singleton births only.

Very Preterm Birth - The birth of an infant less than 32 weeks gestation.  For Tracking, preterm births are measured among singleton births only.

Violation - A failure to meet any state or federal drinking water regulation.

Volatile Organic Compounds (VOCs) - Organic compounds that evaporate readily into the air. VOCs include substances such as benzene, toluene, methylene chloride, and methyl chloroform.

Vulnerability - Sensitivity or susceptibility to environmental health problems.

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Water Vending - Means operations that vend water for drinking that is dispensed or supplied from a water vending machine. This does not include water placed in sealed containers by bottlers and sold in vending machines.

Wholesale - Means sale to retail establishments and anyone other than the ultimate consumer.

Wholesale Food Processor - Means any activity comprising any, or all, of the following: prepares, processes, manufactures, packs, repacks, cans, bottles, keeps, exposes, stores, handles, or distributes foods, or operates a food warehouse. These products are not sold directly to consumer, but are sold to retail establishments. This term includes residential kitchens licensed by the MDPH to operate at wholesale.

Wholesale Seafood Operation - Means any activity comprising any, or all, of the following: handling, storing, preparing, heading, eviscerating, shucking, freezing, manufacturing, preserving, packing, labeling, shipping or selling raw fish and/or shellfish, whether frozen or unfrozen, in bulk or for resale not directly to the consumer in a facility approved by the MDPH.

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