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(a/k/a Tanapag Village (Saipan))
Tanapag Village, Saipan, Commonwealth of the Northern Marianas Island
EPA Facility ID: MPD982524506
August 31, 2004

Figure 1. Saipan location mapFigure 1. Saipan location map

Figure 2.Tanapag location mapFigure 2. Tanapag location map

Figure 3.EPA Multi-matrix sampling survey map: PCB Sample Locations - May 2000Figure 3. EPA Multi-matrix sampling survey map: PCB Sample Locations - May 2000

Figure 4.Tons of PCB-Contaminated Soil Removed from Tanapag Village, SaipanFigure 4. Tons of PCB-Contaminated Soil Removed from Tanapag Village, Saipan

Figure 5.Maximum Pre-excavation PCB Concentrations in Surface Soil, Tanapag Village, SaipanFigure 5. Maximum Pre-excavation PCB Concentrations in Surface Soil, Tanapag Village, Saipan

Figure 6.Distribution of Serum PCB Concentrations Among Tanapag residents, May 2000Figure 6. Distribution of Serum PCB Concentrations Among Tanapag residents, May 2000

Figure 7.Average Serum PCB Levels in Tanapag Residents by Age and GenderFigure 7. Average Serum PCB Levels in Tanapag Residents by Age and Gender

Figure 8.Lipid Corrected Serum PCB ComparisonFigure 8. Lipid Corrected Serum PCB Comparison

Figure 9.Landcrab Sampling Locations (December 2000)Figure 9. Landcrab Sampling Locations (December 2000)

ATSDR Activity Time line
May/June 1999 Visit to Saipan
At the EPA's request, the Agency for Toxic Substances and Disease Registry (ATSDR) visited Tanapag Village to meet with local officials, community members and provide information and educational flyers about ATSDR and PCBs to the Department of Public Health and Department of Environmental Quality.
October 1999 Attended Public Availability Sessions
The ATSDR Regional Office in San Francisco attended public availability sessions and provided toxicological profiles, case studies, and other education materials on PCBs to Saipan environmental and health professionals.
November 1999 Review of ACOE Report
The ATSDR Regional Office in San Francisco reviewed the Army Corps of Engineers' (ACOE) draft project remediation report. Concerns for contamination in cemetery soils led to temporary cover placement.

Received Petition to Conduct Health Assessment
The Commonwealth of Northern Mariana Islands (CNMI) Secretary of Health petitioned ATSDR to perform 1) a public health assessment in Tanapag Village, Saipan of the polychlorinated biphenyl (PCB) contamination from abandoned capacitors, and 2) an exposure investigation of individuals potentially exposed to PCBs.
January 2000 Performed Grand Rounds
ATSDR provided education to CNMI health care providers, including the health effects of PCBs and training on taking exposure histories while on grand rounds in Saipan.
February 2000 Responded to White House Request
ATSDR provided information about Saipan in response to a request from the White House for updates on Insular Areas.
March 2000 Commented on CNMI's Medical Evaluation Report
ATSDR reviewed and commented on the CNMI Secretary of Health's "Medical PCB Evaluation of Tanapag Village." ATSDR also provided comments on U.S. Environmental Protection Agency's (EPA) proposed sampling plan for Tanapag Village and the EPA's draft of the EPA/ACOE action plan for site remediation and proposed PCB clean up levels.

Participated in Weekly Teleconference Calls
ATSDR participated in weekly teleconference calls with the Secretary of Health for the CNMI Department of Public Health (DPH), Department of Environmental Quality (DEQ), members of the Citizens Task Force, EPA, and the U.S. Army.
April 2000 Prepared and Released Public Health Action Plan
ATSDR released a public health action plan for Tanapag Village detailing ATSDR's proposal and time line of public health actions. This document includes: Communication Strategy Development and Community Involvement; Consultation on CNMI Medical Evaluations; Capacity Building for Health Education; Exposure Investigation; Review of Environmental Data; and Reports on ATSDR's Evaluation of Possible Environmental Exposures in Tanapag Village (ATSDR 200b).

Prepared and Released Exposure Investigation Protocol
ATSDR released the Exposure Investigation Protocol for PCB serum sampling of Tanapag Village residents.
May 2000 Visit to Saipan
ATSDR conducted a joint site visit with the EPA and the ACOE. ATSDR participated in public meetings, trained local health department staff, and assisted with exposure histories, medical evaluations, and EPA sampling efforts.
May 2000 Assistance in Tanapag Clinic
More than 1,100 villagers in Tanapag received physical examinations, exposure histories, and blood testing for PCBs. ATSDR staff provided consultation on medical evaluations and exposure histories, and worked on developing plans for communication of test results and management of data.
June-September 2000 Provided Technical Support and Consultation for PCB Blood Testing
ATSDR provided technical support and consultation to the CNMI DPH on interpreting the results of exposure histories and PCB blood testing, and on planning appropriate follow up actions.

Developed Health Education Messages
With the CNMI DPH, ATSDR developed health education messages about exposure to PCBs and health effects.

Conducted a Health Education Needs Assessment
ATSDR began to conduct a health education needs assessment.
August 2000 Commented on EPA/ACOE Land Crab Sampling Data
ATSDR provided consultation and comments to the EPA and ACOE on the land crab environmental sampling data and remedial technology for soil.

Commented on Types of PCB Sampling
ATSDR researched and commented on the adequacy of PCB serum testing versus adipose tissue sampling.
October 2000 Reviewed EPA's Biota Sampling Data
ATSDR reviewed the EPA's biota sampling data collected during the screening survey, made recommendations regarding the health impact of PCB contamination, assisted in developing a plan to fill critical sampling gaps, and provided input into the need for a crab consumption advisory. ATSDR also provided technical assistance to the EPA on the statistical design and development of Phase II land crab sampling.
November 2000 Visited Saipan to Participate in Public Meetings about PCB Blood Sampling
ATSDR visited Saipan to participate in public meetings and to communicate the results of the PCB blood sampling and exposure investigation. This included participating in follow-up medical examinations, public hearings, and grand rounds, and providing public health education materials to both the local health care providers and the community. Additionally, ATSDR counseled 17 individuals with total PCB levels greater than 10 parts per billion (ppb) about the health significance of their blood level. An ATSDR physician also saw 30 individuals who had abnormal lab results or other health concerns. ATSDR counseled Tanapag residents with normal PCB lab results who still had concerns about environmental contamination. Additionally, information repositories were established in the local library and Tanapag clinic. ATSDR worked with the CNMI DPH medical staff to identify data needed to perform a descriptive analysis of disease incidence and mortality in Tanapag. ATSDR also identified what may be needed to develop a future disease surveillance data collection system for Saipan.

Met with Agencies about Crab Sampling
ATSDR met with representatives from the EPA Region IX, DPH, Saipan Department of Fish and Game, CNMI DEQ, and members of the Tanapag community to identify crab sampling areas and plan logistics for the follow-up round of crab sampling.

Met with ACOE about Remediation Activities
ATSDR met with the ACOE to discuss the status of the Army's ongoing removal actions, further sampling, and the installation of protective measures to prevent further contact with contamination, such as access restrictions and air sampling.

Collected Sampling Information at Fuel Tank Storage Area
ATSDR toured and collected environmental sampling information on another area of community concern in Tanapag involving bulk fuel storage tanks.

Project Update and Briefing
ATSDR provided a project update and briefing for the National Association of State and Territorial Health Officials (NACCHO).
December 2000 Commented on EPA Crab Sampling Plan
ATSDR reviewed and provided comment on the draft EPA Phase II crab sampling plan.

Reviewed Data on PCBs in Yams and Taro
ATSDR provided technical assistance to local health agencies and communities by reviewing data and commenting on concerns about PCB contamination in yams and taro.

Commented on Thermal Desorption Plan
ATSDR commented on the thermal desorption/Fenton reaction method planned for use by the ACOE in remediating soils.

Responded to Concerns about Testing for Aroclor 1260 vs. 1254
ATSDR responded to community, local physician, and DPH concerns about blood serum levels and why using Aroclor 1260 instead of Aroclor 1254 as a standard for analyzing the serum was adequate.
January 2001 Assistance with Congener Analysis
At the request of the CNMI Secretary of Public Health, ATSDR agreed to provide assistance with a limited exposure investigation and a congener specific analysis for approximately 20 residents of Tanapag Village who participated in the May 2000 exposure investigation.

Comments on Joint Agency Documents
ATSDR provided technical assistance to the EPA by providing input, review, and comments on drafts of joint agency fact sheets and communication strategy documents.
April 2001 Released Exposure Investigation Report
The exposure investigation report (health consultation) conducted by ATSDR and the CNMI DPH was released. Based on the levels of PCBs detected in the blood serum, it does not appear that the population tested is being exposed to PCBs at levels of health concern.
From: FY 2001

Commented on CNMI Hazardous Substance Regulations
ATSDR provided comments on CNMI DEQ's Harmful Substances Clean Up Regulations.
July 2001 Released Health Consultation on PCBs in Land Crabs
ATSDR released a health consultation for PCB contamination in land crabs and determined that the contamination did not pose a public health hazard.

Commented on EPA Update Report
ATSDR commented on the EPA draft of the Tanapag Village PCB Update on Sampling and Cleanup Activities.
August 2001 Wrote to Newspaper Editor
ATSDR wrote a letter to the editor of the Saipan Tribune newspaper concerning ATSDR activities.

Provided Assistance to Community Member
ATSDR provided technical assistance to a community member on PCB toxicity and exposure.
October 2001 Provided a Verbal Health Consultation and a Review of EPA Military Dump site report
EPA forwarded and requested review and comment on their report documenting their remedial investigation of the military dump site near Tanapag. The sampling identified low concentrations of several heavy metals that did not exceed health-based soil criteria. Additionally, due to the inaccessibility and overgrowth in the area, exposure to contaminated soil is restricted.
December 2001 Provided a Verbal Health Consultation and a Review of Site Safety and Health Plan
EPA forwarded and requested review and comment on the site safety and health plan for the soil remediation work at the Tanapag village PCB site. EPA was specifically interested in getting input on air sampling and monitoring for fugitive dusts, dust mitigation measures and action levels for dusts containing PCB residues.
December 2001 Coordinated and performed phase II blood sampling and analysis, interpret PCB congener-specific data on a subset of Tanapag villagers previously tested.
March 2002 Provided a Verbal/Email Health Consultation related to Questions on Known Associations between PCB Exposure and Diabetes
EPA requested information on known associations between PCB exposure and diabetes. We reported that studies of PCB-exposed workers reveal no suggestion of an increased level of glucose, morbidity, or mortality from diabetes. However, the diabetes in such studies would be primarily type 2. As part of our work, we looked at the exposure history and medical screening data collected in Tanapag to see if there is any association between PCB serum levels, exposure history variables and the health status of the villagers. The did not appear to be an association.
June 2002 Communicated with DPH about Phase II blood sampling results and provided interpretation.
June 2002 Provided a Verbal/Email Health Consultation and Commented on the ACOE Particulate Levels from Soil Treatment
EPA requested ATSDR's comment on the proposed action levels on particulates generated from the soil treatment. During a June 19, 2002 conference call, ATSDR, EPA, and the ACOE agreed to a 24-hour action level of 0.26 mg/m3 for total suspended particulates. Previously, EPA and ATSDR had proposed an action level of 0.15 mg/m3 as appropriate to protect sensitive individuals and consistent with standards used at other sites. EPA also requested ATSDR's recommendation for a short-term action level. ATSDR considered a short-term action level between 1 and 3 mg/m3 as appropriate as long a site activity stopped once this level was exceeded in a 10 to 15 minute exposure period. ATSDR recommended that monitoring be conducted according to wind direction; to accomplish that, more monitors may be needed. Additionally, verification is needed that no other hazards exist in the dust, primarily, metals. ACOE followed ATSDR recommendations.

ATSDR Glossary of Environmental Health Terms

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.

CERCLA [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].

Organic compounds found in plants and animals that are insoluble in water, but soluble in alcohol. Lipids are often referred to as fats.

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.

NPL [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.

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.

RCRA [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.

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]

SARA [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.

Semivolatile organic compounds (SVOCs)
Organic compounds that evaporate slowly into the air. SVOCs include substances such as benzo(a)pyrene, bis(2-ethylhexyl)phthalate, and phenol.

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.

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].

Surveillance [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].

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.

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