PUBLIC HEALTH ASSESSMENT
CAYUGA COUNTY GROUNDWATER CONTAMINATION
UNION SPRINGS, CAYUGA COUNTY, NEW YORK
|# wells where detected||65||53||54||25|
|# wells where not detected||3||15||14||43|
|range detected (mcg/L)||ND* to 980||ND* to 20||ND* to 62||ND* to 42|
|average where detected (mcg/L)||253||6.1||22.5||9.6|
* Detection Limit 0.5 mcg/L.
Table 2. Water Quality Standards/Guidelines and /or Public Health Assessment Comparison Values Exceeded by Contaminants Found in Private Wells Affected by the Cayuga County Groundwater Contamination
[All values in micrograms per liter (mcg/L)]
|Water Quality Standards/Guidelines||Comparison Values*|
|New York State||US EPA|
|trichloroethene||5||5||5||5a||3.2||EPA RBC||42||EPA RBC|
|vinyl chloride||2||0.3b||2||2||0.023||EPA CPF||21||EPA RfD|
* Comparison values determined for a 70 kilogram adult who drinks 2 liters of water per day. Cancer comparison values correspond to a contaminant intake associated with an increased lifetime cancer risk of one-in-one million. Noncancer comparison values correspond to a contaminant intake that is estimated to be without an appreciable risk of noncancer health effects.
** EPA CPF: Environmental Protection Agency Cancer Potency
EPA HEAST: Environmental Protection Agency (Region 3) Health Effects Assessment Summary Tables (April 2001).
EPA RBC: Environmental Protection Agency Risk-Based Concentration Table.
EPA RfD: Environmental Protection Agency Reference Dose.
a Under review.
b Guidance value.
To evaluate the potential health risks from contaminants of concern associated with the Cayuga County Groundwater Contamination site, the New York State Department of Health assessed the risks for cancer and noncancer health effects.
Increased cancer risks were estimated by using site-specific information on exposure levels for the contaminant of concern and interpreting them using cancer potency estimates derived for that contaminant by the US EPA or, in some cases, by the NYS DOH. The following qualitative ranking of cancer risk estimates, developed by the NYS DOH, was then used to rank the risk from very low to very high. For example, if the qualitative descriptor was "low", then the excess lifetime cancer risk from that exposure is in the range of greater than one per million to less than one per ten thousand. Other qualitative descriptors are listed below:
|Excess Lifetime Cancer Risk|
|Risk Ratio||Qualitative Descriptor|
|equal to or less than one per million||very low|
|greater than one per million to less than one per ten thousand||low|
|one per ten thousand to less than one per thousand||moderate|
|one per thousand to less than one per ten||high|
|equal to or greater than one per ten||very high|
An estimated increased excess lifetime cancer risk is not a specific estimate of expected cancers. Rather, it is a plausible upper bound estimate of the probability that a person may develop cancer sometime in his or her lifetime following exposure to that contaminant.
There is insufficient knowledge of cancer mechanisms to decide if there exists a level of exposure to a cancer-causing agent below which there is no risk of getting cancer, namely, a threshold level. Therefore, every exposure, no matter how low, to a cancer-causing compound is assumed to be associated with some increased risk. As the dose of a carcinogen decreases, the chance of developing cancer decreases, but each exposure is accompanied by some increased risk.
There is general consensus among the scientific and regulatory communities on what level of estimated excess cancer risk is acceptable. An increased lifetime cancer risk of one in one million or less is generally not considered a significant public health concern.
For noncarcinogenic health risks, the contaminant intake was estimated using exposure assumptions for the site conditions. This dose was then compared to a risk reference dose (estimated daily intake of a chemical that is likely to be without an appreciable risk of health effects) developed by the US EPA, ATSDR and/or NYS DOH. The resulting ratio was then compared to the following qualitative scale of health risk:
|Qualitative Descriptions for Noncarcinogenic Health Risks|
|Ratio of Estimated Contaminant Intake to Risk Reference Dose||Qualitative Descriptor|
|equal to or less than the risk reference dose||minimal|
|greater than one to five times the risk reference dose||low|
|greater than five to ten times the risk reference dose||moderate|
|greater than ten times the risk reference dose||high|
Noncarcinogenic effects unlike carcinogenic effects are believed to have a threshold, that is, a dose below which adverse effects will not occur. As a result, the current practice is to identify, usually from animal toxicology experiments, a no-observed-effect-level (NOEL). This is the experimental exposure level in animals at which no adverse toxic effect is observed. The NOEL is then divided by an uncertainty factor to yield the risk reference dose. The uncertainty factor is a number which reflects the degree of uncertainty that exists when experimental animal data are extrapolated to the general human population. The magnitude of the uncertainty factor takes into consideration various factors such as sensitive subpopulations (for example, children or the elderly), extrapolation from animals to humans, and the incompleteness of available data. Thus, the risk reference dose is not expected to cause health effects because it is selected to be much lower than dosages that do not cause adverse health effects in laboratory animals.
The measure used to describe the potential for noncancer health effects to occur in an individual is expressed as a ratio of estimated contaminant intake to the risk reference dose. A ratio equal to or less than one is generally not considered a significant public health concern. If exposure to the contaminant exceeds the risk reference dose, there may be concern for potential noncancer health effects because the margin of protection is less than that afforded by the reference dose. As a rule, the greater the ratio of the estimated contaminant intake to the risk reference dose, the greater the level of concern. This level of concern depends upon an evaluation of a number of factors such as the actual potential for exposure, background exposure, and the strength of the toxicologic data.
|CATEGORY / DEFINITION||DATA SUFFICIENCY||CRITERIA|
|A. Urgent Public Health Hazard
This category is used for sites where short-term exposures (< 1 yr) to hazardous substances or conditions could result in adverse health effects that require rapid intervention.
|This determination represents a professional judgement based on critical data which ATSDR has judged sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made.||Evaluation of available relevant information* indicates that site-specific conditions or likely exposures have had, are having, or are likely to have in the future, an adverse impact on human health that requires immediate action or intervention. Such site-specific conditions or exposures may include the presence of serious physical or safety hazards.|
|B. Public Health Hazard
This category is used for sites that pose a public health hazard due to the existence of long-term exposures (> 1 yr) to hazardous substance or conditions that could result in adverse health effects.
|This determination represents a professional judgement based on critical data which ATSDR has judged sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made.||Evaluation of available relevant information* suggests that, under site-specific conditions of exposure, long-term exposures to site-specific contaminants (including radionuclides) have had, are having, or are likely to have in the future, an adverse impact on human health that requires one or more public health interventions. Such site-specific exposures may include the presence of serious physical or safety hazards.|
|C. Indeterminate Public Health Hazard
This category is used for sites in which "critical" data are insufficient with regard to extent of exposure and/or toxicologic properties at estimated exposure levels.
|This determination represents a professional judgement that critical data are missing and ATSDR has judged the data are insufficient to support a decision. This does not necessarily imply all data are incomplete; but that some additional data are required to support a decision.||The health assessor must determine, using professional judgement, the "criticality" of such data and the likelihood that the data can be obtained and will be obtained in a timely manner. Where some data are available, even limited data, the health assessor is encouraged to the extent possible to select other hazard categories and to support their decision with clear narrative that explains the limits of the data and the rationale for the decision.|
|D. No Apparent Public Health Hazard
This category is used for sites where human exposure to contaminated media may be occurring, may have occurred in the past, and/or may occur in the future, but the exposure is not expected to cause any adverse health effects.
|This determination represents a professional judgement based on critical data which ATSDR considers sufficient to support a decision. This does not necessarily imply that the available data are complete; in some cases additional data may be required to confirm or further support the decision made.||Evaluation of available relevant information* indicates that, under site-specific conditions of exposure, exposures to site-specific contaminants in the past, present, or future are not likely to result in any adverse impact on human health.|
|E: No Public Health Hazard
This category is used for sites that, because of the absence of exposure, do NOT pose a public health hazard.
|Sufficient evidence indicates that no human exposures to contaminated media have occurred, none are now occurring, and none are likely to occur in the future|
*Such as environmental and demographic data; health outcome data; exposure data; community health concerns information; toxicologic, medical, and epidemiologic data; monitoring and management plans.
This summary was prepared to address comments and questions on the public comment draft of the Cayuga County Groundwater Contamination Public Health Assessment. The public was invited to review the draft during the public comment period which ran from November 13, 2002 to December 15, 2002. We received two written sets of comments from residents. Similar comments may be consolidated or grouped together and some statements reworded to clarify the comment. If you have any questions about this summary, you may contact Henrietta Hamel of the New York State Department of Health (NYS DOH) at 1-315-426-7612 or by e-mail at firstname.lastname@example.org.
Comment #1 - A resident reported that land around Bluefield and Experimental roads was used as a dumping ground by the suspected polluter. Has soil testing, especially in heavily contaminated areas, been considered?
Response - The NYS DOH and New York State Department of Environmental Conservation (NYS DEC), and the US Environmental Protection Agency (US EPA) have received no evidence that the land around Bluefield and Experimental Roads was used by any industry for disposal of wastes. This comment has been forwarded to these agencies for their consideration. Anyone with additional information should contact the NYS DEC at 315-426-7400 or the US EPA at 212-637-4248. Soil sampling within the currently known plume area has not been considered since a source has not been identified. Thus far the contaminants have been found in deep wells, not shallow ones, indicating that impacted wells are downgradient of an unknown source. The US EPA is drilling test wells to track the plume back to its upgradient source.
Comment #2 - A resident asked how long the NYS DOH Volatile Organic Compound (VOC) Registry has been in existence.
Response - In July 1999, the VOC Registry began enrolling individuals who had been exposed to VOCs in the past. Registration of residents who were exposed to VOCs at the Cayuga County Groundwater Contamination site has been ongoing since January 2001.
Comment #3 - A resident questioned why private water sampling didn't begin in 1988.
Response - When low level contamination was first discovered in the Union Springs public wells in 1988, the search for a source of the chlorinated solvents was focused in the immediate area of Union Springs. None was found. Private wells available for sampling around the Village, at the outskirts of the public water supply, were sampled by the NYS DOH in the late 80's. However, no contamination was detected in the wells.
Comment #4 - A resident questioned the scientific validity of doubling the measured concentration in drinking water to account for additional exposure.
Response - The reason for doubling the drinking water concentration of volatile organic compounds is because of the other routes of exposure to these contaminants in drinking water in addition to ingesting the water. VOCs will evaporate into air and the warmer the temperature, the quicker the compounds will leave water and go into the air. For example, when bathing or showering VOCs will evaporate into the air, creating the potential for exposure by inhalation. Showering and bathing also allow for additional exposure through the skin. Our practice of doubling the concentration of VOCs in drinking water provides a way to estimate additional exposures from inhalation or dermal routes. The potential for exposure to VOCs in drinking water by routes other than ingestion is documented in the peer reviewed scientific literature. Examples of these published references are available upon request.
Comment #5 - A resident requested a list of other sites in New York State with similar water contamination issues.
Response - There are large number of hazardous waste sites in New York with groundwater contamination. A complete list of sites in New York can be obtained from the NYS DEC. The NYS DOH and ATSDR have drafted public health assessments on several sites with groundwater contamination. Recent examples include the Smithtown Groundwater Contamination site in Suffolk County, the 150 Fulton Avenue/Garden City Park Industrial Area site in Nassau County, and the Shenandoah Road Groundwater Contamination site in Dutchess County. Copies of these public health assessments can be requested by calling the NYS DOH toll-free number: 1-800-458-1158.
Comment #6 - A resident questioned the exclusion of test well results from the General Electric plant.
Response - Results from the samples taken at test wells from the Former General Electric Powerex site were not included in the Public Health Assessment because the focus of the document is the public health impact of contamination of private drinking water wells in the plume area. Data from the investigations conducted at the Former General Electric Powerex site do not indicate that the site is a source of groundwater contamination to the Cayuga County Groundwater Contamination site, that cleanup efforts at the site will affect the Cayuga County Groundwater Contamination site, or that there are any human exposures in common between the two sites. Information about the General Electric Powerex site, including investigations and sample results, is available to the public at a document repository at the Aurelius Town Hall, the Seymour Library in the City of Auburn or by calling the NYS DEC Region 7 Office at 315-426-7400.
Comment #7 - A resident requested a health study of General Electric workers and people who lived in the area before the installation of public water.
Response - This Public Health Assessment for the Cayuga County Groundwater Contamination site does not address former GE plant workers. To our knowledge workers at the Former GE Powerex plant were not exposed to contaminated drinking water. Assessment of exposures in an industrial setting to chemicals used in the workplace are not within the scope of this document as defined by the site. As mentioned in the Health Outcome Data section, residents of households who were exposed to VOCs will be enrolled in the VOC registry. This will allow long term follow up of the health status of persons with documented exposures.
Comment #8 - A resident questioned why soil removal was not included in the recommendations.
Response - Soil removal was not included in the recommendations because we do not know of any contaminated soil. Once a source is found, it will be delineated, and remedial measures will be proposed and implemented as needed. If contaminated soil is found to be releasing contaminants to the groundwater or is the source of other potential exposures, removal or treatment may be considered. There will be public participation in the process.
Comment #9 - A resident asked why no public meetings have been held in over a year.
Response -There have been no public meetings within the last year because there has been no news to report. The NYS DOH monitoring program has not detected any changes in the plume. The site's inclusion on the National Priorities List, the arrival of the US EPA as the lead investigating agency and the water main extension just south of Auburn have all been reported in the local press.
The Agency for Toxic Substances and Disease Registry (ATSDR) is a federal public health agency with headquarters in Atlanta, Georgia, and 10 regional offices in the United States. ATSDR's mission is to serve the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and diseases related to toxic substances. ATSDR is not a regulatory agency, unlike the U.S. Environmental Protection Agency (EPA), which is the federal agency that develops and enforces environmental laws to protect the environment and human health. This glossary defines words used by ATSDR in communications with the public. It is not a complete dictionary of environmental health terms. If you have questions or comments, call ATSDR's toll-free telephone number, 1-888-42-ATSDR (1-888-422-8737).
- The process of taking in. For a person or animal, absorption is the process of a substance getting into the body through the eyes, skin, stomach, intestines, or lungs.
- Occurring over a short time [compare with chronic].
- Acute exposure:
- Contact with a substance that occurs once or for only a short time (up to 14 days) [compare with intermediate duration exposure and 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 and synergistic effect].
- Adverse health effect:
- A change in body function or cell structure that might lead to disease or health problems.
- Requiring oxygen [compare with anaerobic].
- Surrounding (for example, ambient air).
- Requiring the absence of oxygen [compare with aerobic].
- A substance measured in the laboratory. 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.
- 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 and synergistic effect].
- Background level:
- An average or expected amount of a substance or radioactive material in a specific environment, or typical amounts of substances that occur naturally in an environment.
- 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 [also see exposure investigation].
- Biologic monitoring :
- Measuring hazardous substances in biologic materials (such as blood, hair, urine, or breath) to determine whether exposure has occurred. 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.
- Plants and animals in an environment. Some of these plants and animals might be sources of food, clothing, or medicines for people.
- 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.
- [See Community Assistance Panel].
- Any one of a group of diseases that occurs when cells in the body become abnormal and grow or multiply out of control.
- Cancer risk:
- A theoretical risk of for getting cancer if exposed to a substance every day for 70 years (a lifetime exposure). The true risk might be lower.
- A substance that causes cancer.
- Case study:
- A medical or epidemiologic evaluation of one person or a small group of people to gather information about specific health conditions and past exposures.
- Case-control study:
- A study that compares exposures of people who have a disease or condition (cases) with people who do not have the disease or condition (controls). Exposures that are more common among the cases may be considered as possible risk factors for the disease.
- CAS registry number:
- A unique number assigned to a substance or mixture by the American Chemical Society Abstracts Service.
- Central nervous system:
- The part of the nervous system that consists of the brain and the spinal cord.
- [see Comprehensive Environmental Response, Compensation, and Liability Act of 1980]
- Occurring over a long time (more than 1 year) [compare with acute].
- Chronic exposure:
- Contact with a substance that occurs over a long time (more than 1 year) [compare with acute exposure and intermediate duration exposure].
- 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.
- Community Assistance Panel (CAP):
- A group of people, from a community and from health and environmental agencies, who work with ATSDR to resolve issues and problems related to hazardous substances in the community. CAP members work with ATSDR to gather and review community health concerns, provide information on how people might have been or might now be exposed to hazardous substances, and inform ATSDR on ways to involve the community in its activities.
- Comparison value (CV):
- Calculated concentration of a substance in air, water, food, or soil that is unlikely to cause harmful (adverse) health effects in exposed people. The CV is used as a screening level during the public health assessment process. Substances found in amounts greater than their CVs might be selected for further evaluation in the public health assessment process.
- Completed exposure pathway:
- [see exposure pathway].
- 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.
- The amount of a substance present in a certain amount of soil, water, air, food, blood, hair, urine, breath, or any other media.
- 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.
- Delayed health effect:
- A disease or injury that happens as a result of exposures that might have occurred in the past.
- Referring to the skin. For example, dermal absorption means passing through the skin.
- Dermal contact:
- Contact with (touching) the skin [see route of exposure].
- Descriptive epidemiology:
- The study of the amount and distribution of a disease in a specified population by person, place, and time.
- Detection limit:
- The lowest concentration of a chemical that can reliably be distinguished from a zero concentration.
- Disease prevention:
- Measures used to prevent a disease or reduce its severity.
- Disease registry:
- A system of ongoing registration of all cases of a particular disease or health condition in a defined population.
- United States Department of Defense.
- United States Department of Energy.
- Dose (for chemicals that are not radioactive):
- The amount of a substance to which a person is exposed over some time period. Dose is a measurement of exposure. Dose is often expressed as milligram (amount) per kilogram (a measure of body weight) per day (a measure of time) when people eat or drink contaminated water, food, or soil. In general, the greater the dose, the greater the likelihood of an effect. An "exposure dose" is how much of a substance is encountered in the environment. An "absorbed dose" is the amount of a substance that actually got into the body through the eyes, skin, stomach, intestines, or lungs.
- Dose (for radioactive chemicals):
- The radiation dose is the amount of energy from radiation that is actually absorbed by the body. This is not the same as measurements of the amount of radiation in the environment.
- Dose-response relationship:
- The relationship between the amount of exposure [dose] to a substance and the resulting changes in body function or health (response).
- Environmental media:
- Soil, water, air, biota (plants and animals), or any other parts of the environment that can contain contaminants.
- Environmental media and transport mechanism:
- Environmental media include water, air, soil, and biota (plants and animals). Transport mechanisms 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.
- United States Environmental Protection Agency.
- Epidemiologic 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.
- 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.
- Contact with a substance 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 for how long they are in contact with the substance, and how much of the substance they are in contact with.
- Exposure-dose reconstruction:
- A method of estimating the amount of people's past exposure to hazardous substances. Computer and approximation methods are used when past information is limited, not available, or missing.
- 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 an abandoned business);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.
- Exposure registry:
- A system of ongoing followup of people who have had documented environmental exposures.
- Feasibility study:
- A study by EPA to determine the best way to clean up environmental contamination. A number of factors are considered, including health risk, costs, and what methods will work well.
- 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.
- Grand rounds:
- Training sessions for physicians and other health care providers about health topics.
- Water beneath the earth's surface in the spaces between soil particles and between rock surfaces [compare with surface water].
- Half-life (t½):
- The time it takes for half the original amount of a substance to disappear. In the environment, the half-life is the time it takes for half the original amount of a substance to disappear when it is changed to another chemical by bacteria, fungi, sunlight, or other chemical processes. In the human body, the half-life is the time it takes for half the original amount of the substance to disappear, either by being changed to another substance or by leaving the body. In the case of radioactive material, the half life is the amount of time necessary for one half the initial number of radioactive atoms to change or transform into another atom (that is normally not radioactive). After two half lives, 25% of the original number of radioactive atoms remain.
- A source of potential harm from past, current, or future exposures.
- 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 consultation:
- A review of available information or collection of new data to respond to a specific health question or request for information about a potential environmental hazard. Health consultations are focused on a specific exposure issue. Health consultations are therefore more limited than a public health assessment, which reviews the exposure potential of each pathway and chemical [compare with public health assessment].
- Health education:
- Programs designed with a community to help it know about health risks and how to reduce these risks.
- 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 estimate the possible association between the occurrence and exposure to hazardous substances.
- Health promotion:
- The process of enabling people to increase control over, and to 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.
- Indeterminate public health hazard:
- The category used in ATSDR's public health assessment documents when a professional judgment about the level of health hazard cannot be made because information critical to such a decision is lacking.
- The number of new cases of disease in a defined population over a specific time period [contrast with prevalence].
- The act of swallowing something through eating, drinking, or mouthing objects. A hazardous substance can enter the body this way [see route of exposure].
- The act of breathing. A hazardous substance can enter the body this way [see route of exposure].
- Intermediate duration exposure:
- Contact with a substance that occurs for more than 14 days and less than a year [compare with acute exposure and chronic exposure].
- In vitro:
- In an artificial environment outside a living organism or body. For example, some toxicity testing is done on cell cultures or slices of tissue grown in the laboratory, rather than on a living animal [compare with in vivo].
- In vivo:
- Within a living organism or body. For example, some toxicity testing is done on whole animals, such as rats or mice [compare with in vitro].
- Lowest-observed-adverse-effect level (LOAEL):
- The lowest tested dose of a substance that has been reported to cause harmful (adverse) health effects in people or animals.
- Medical monitoring:
- A set of medical tests and physical exams specifically designed to evaluate whether an individual's exposure could negatively affect that person's health.
- The conversion or breakdown of a substance from one form to another by a living organism.
- Any product of metabolism.
- Milligram per kilogram.
- Milligram per square centimeter (of a surface).
- Milligram per cubic meter; a measure of the concentration of a chemical in a known volume (a cubic meter) of air, soil, or water.
- Moving from one location to another.
- Minimal risk level (MRL):
- An ATSDR estimate of daily human exposure to a hazardous substance at or below which that substance is unlikely to pose a measurable risk of harmful (adverse), noncancerous effects. MRLs are calculated for a route of exposure (inhalation or oral) over a specified time period (acute, intermediate, or chronic). MRLs should not be used as predictors of harmful (adverse) health effects [see reference dose].
- State of being ill or diseased. Morbidity is the occurrence of a disease or condition that alters health and quality of life.
- Death. Usually the cause (a specific disease, condition, or injury) is stated.
- A substance that causes mutations (genetic damage).
- A change (damage) to the DNA, genes, or chromosomes of living organisms.
- National Priorities List for Uncontrolled Hazardous Waste Sites (National Priorities List or NPL):
- 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.
- No apparent public health hazard:
- A category used in ATSDR's public health assessments for sites where human exposure to contaminated media might be occurring, might have occurred in the past, or might occur in the future, but where the exposure is not expected to cause any harmful health effects.
- No-observed-adverse-effect level (NOAEL):
- The highest tested dose of a substance that has been reported to have no harmful (adverse) health effects on people or animals.
- No public health hazard:
- A category used in ATSDR's public health assessment documents for sites where people have never and will never come into contact with harmful amounts of site-related substances.
- [see National Priorities List for Uncontrolled Hazardous Waste Sites].
- Physiologically based pharmacokinetic model (PBPK model):
- A computer model that describes what happens to a chemical in the body. This model describes how the chemical gets into the body, where it goes in the body, how it is changed by the body, and how it leaves the body.
- A craving to eat nonfood items, such as dirt, paint chips, and clay. Some children exhibit pica-related behavior.
- A volume of a substance that moves from its source to places farther away from the source. Plumes can be described by the volume of air or water they occupy and the direction they move. For example, a plume can be a column of smoke from a chimney or a substance moving with groundwater.
- Point of exposure:
- The place where someone can come into contact with a substance present in the environment [see exposure pathway].
- A group or number of people living within a specified area or sharing similar characteristics (such as occupation or age).
- Potentially responsible party (PRP):
- A company, government, or person legally responsible for cleaning up the pollution at a hazardous waste site under Superfund. There may be more than one PRP for a particular site.
- Parts per billion.
- Parts per million.
- Prevalence :
- The number of existing disease cases in a defined population during a specific time period [contrast with incidence].
- Prevalence survey:
- The measure of the current level of disease(s) or symptoms and exposures through a questionnaire that collects self-reported information from a defined population.
- Actions that reduce exposure or other risks, keep people from getting sick, or keep disease from getting worse.
- Public comment period:
- An opportunity for the public to comment on agency findings or proposed activities contained in draft reports or documents. The public comment period is a limited time period during which comments will be accepted.
- Public availability session:
- An informal, drop-by meeting at which community members can meet one-on-one with ATSDR staff members to discuss health and site-related concerns.
- Public health action:
- A list of steps to protect public health.
- Public health advisory:
- A statement made by ATSDR to 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 [compare with health consultation].
- 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 statement:
- The first chapter of an ATSDR toxicological profile. The public health statement is a summary written in words that are easy to understand. The public health statement explains how people might be exposed to a specific substance and describes the known health effects of that substance.
- Public meeting:
- A public forum with community members for communication about a site.
- An unstable or radioactive isotope (form) of an element that can change into another element by giving off radiation.
- Any radioactive isotope (form) of any element.
- [See Resource Conservation and Recovery Act (1976, 1984)]
- Receptor population:
- People who could come into contact with hazardous substances [see exposure pathway].
- Reference dose (RfD):
- An EPA estimate, with uncertainty or safety factors built in, of the daily lifetime dose of a substance that is unlikely to cause harm in humans.
- Registry :
- A systematic collection of information on persons exposed to a specific substance or having specific diseases [see exposure registry and disease registry].
- Remedial Investigation:
- The CERCLA process of determining the type and extent of hazardous material contamination at a site.
- Resource Conservation and Recovery Act (1976, 1984) (RCRA):
- This Act regulates management and disposal of hazardous wastes currently generated, treated, stored, disposed of, or distributed.
- RCRA Facility Assessment. An assessment required by RCRA to identify potential and actual releases of hazardous chemicals.
- See reference dose.
- The probability that something will cause injury or harm.
- Risk reduction:
- Actions that can decrease the likelihood that individuals, groups, or communities will experience disease or other health conditions.
- Risk communication:
- The exchange of information to increase understanding of health risks.
- 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].
- Safety factor:
- [see uncertainty factor].
- [see Superfund Amendments and Reauthorization Act]
- A portion or piece of a whole. A selected subset of a population or subset of whatever is being studied. For example, in a study of people the sample is a number of people chosen from a larger population [see population]. An environmental sample (for example, a small amount of soil or water) might be collected to measure contamination in the environment at a specific location.
- Sample size:
- The number of units chosen from a population or environment.
- A liquid capable of dissolving or dispersing another substance (for example, acetone or mineral spirits).
- 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.
- Special populations:
- People who might be more sensitive or susceptible to exposure to hazardous substances because of factors such as age, occupation, sex, or behaviors (for example, cigarette smoking). Children, pregnant women, and older people are often considered special populations.
- A person, group, or community who has an interest in activities at a hazardous waste site.
- 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.
- 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 would 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.
- Superfund Amendments and Reauthorization Act (SARA):
- In 1986, SARA amended 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].
- [see epidemiologic surveillance]
- 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].
- Synergistic effect:
- A biologic response to multiple substances where one substance worsens the effect of another substance. The combined effect of the substances acting together is greater than the sum of the effects of the substances acting by themselves [see additive effect and antagonistic effect].
- Teratogen :
- A substance that causes defects in development between conception and birth. A teratogen is a substance that causes a structural or functional birth defect.
- Toxic agent:
- Chemical or physical (for example, radiation, heat, cold, microwaves) agents which, under certain circumstances of exposure, can cause harmful effects to living organisms.
- 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.
- The study of the harmful effects of substances on humans or animals.
- 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).
- Uncertainty factor:
- Mathematical adjustments for reasons of safety when knowledge is incomplete. For example, factors used in the calculation of doses that are not harmful (adverse) to people. These factors are applied to the lowest-observed-adverse-effect-level (LOAEL) or the no-observed-adverse-effect-level (NOAEL) to derive a minimal risk level (MRL). Uncertainty factors are used to account for variations in people's sensitivity, for differences between animals and humans, and for differences between a LOAEL and a NOAEL. Scientists use uncertainty factors when they have some, but not all, the information from animal or human studies to decide whether an exposure will cause harm to people [also sometimes called a safety factor].
- Urgent public health hazard:
- A category used in ATSDR's public health assessments for sites where short-term exposures (less than 1 year) to hazardous substances or conditions could result in harmful health effects that require rapid intervention.
- Volatile organic compounds (VOCs):
- Organic compounds that evaporate readily into the air. VOCs include substances such as benzene, toluene, methylene chloride, and methyl chloroform.
Other glossaries and dictionaries:
Environmental Protection Agency (http://www.epa.gov/OCEPAterms/ )
National Center for Environmental Health (CDC) (http://www.cdc.gov/nceh/dls/report/glossary.htm )
National Library of Medicine (http://www.nlm.nih.gov/medlineplus/mplusdictionary.html )
For more information on thw work of ATSDR, please contact:
Office of Policy and External Affairs
Agency for Toxic Substances and Disease Registry
1600 Clifton Road, N.E. (MS E-60)
Atlanta, GA 30333
Telephone: (404) 498-0080