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Glossary of Terms (Marietta Air Emissions Site)

NOTE: If you are interested in other common terms used by ATSDR, please visit the ATSDR Glossary of Terms.

Air quality investigation
A process used to measure the presence and magnitude of chemicals or particles present in ambient air.  The information is then used to assess whether the air in a community poses a risk to human health. Investigations may include a review of existing or newly collected air monitoring data. Investigations may also use air modeling to predict dispersion patterns of air emissions.

Air (dispersion) modeling
A mathematical method to characterize the atmospheric processes that disperse a pollutant through the air. Based on emissions and meteorological inputs, a dispersion model can be used to predict the amount of a pollutant at selected locations downwind of the emission location.

Comprehensive Environmental Response Compensation and Liability Act (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).

Cooperative agreement
A mechanism for ATSDR to technically and financially support state and tribal governments in evaluating and responding to environmental public health issues and to build sustainability in carrying out these activities.

Exposure
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.

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.

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 study
A systematic way to scientifically explore and evaluate exposure-outcome relationships. The information gained from health studies can be used to prevent or reduce the human health hazards for the community studied, as well as other communities with similar environmental exposures.

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.

Interagency agreement (IAA)
A funding mechanism for ATSDR to procure services from other Federal agencies. The Economy Act - 31 U.S.C. 1535 authorizes the head of any agency to obtain goods or services from another agency if it is determined that it is in the best interest of the Government and that the goods or services are less costly, or are not available, or cannot be more conveniently obtained by contracting directly with the private sector.

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.

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 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.

Petition
A process by which a community or an individual requests ATSDR to investigate a potential environmental health concern. Once petitioned, ATSDR decides whether the agency will perform a Public Health Assessment, Public Health Advisory, a Health Consultation, or conduct community environmental health education to meet the community's needs. The petition committee may also decide if no action is needed. Petitioners are informed in writing of ATSDR's decision and the reasons for it.

Priority data needs
An ATSDR process intended to characterize and rank substance-specific data needs identified in ATSDR toxicological profiles. The identified priority data needs reflect the opinion of the Agency, in consultation with other federal programs, of the research necessary for fulfilling its statutory mandate under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (Superfund) or CERCLA.

Priority list of hazardous substances
ATSDR and USEPA prepares and periodically updates a list of substances, in order of priority that are most commonly found at facilities on the National Priorities List (NPL) and which are determined to pose the most significant potential threat to human health due to their known or suspected toxicity and potential for human exposure at these NPL sites. This priority list is not a list of "most toxic" substances, but rather a prioritization of substances based on a combination of their frequency, toxicity, and potential for human exposure at NPL sites.

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 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 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.

Registry
A systematic collection of information on persons exposed to a specific substance or having specific diseases.

Resource Conservation and Recovery Act (RCRA)
This Act regulates management and disposal of hazardous wastes currently generated, treated, stored, disposed of, or distributed.

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.

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.

Toxicological profile
An ATSDR document that examines, summarizes, and interprets associated health effects. A toxicological profile also identifies significant gaps in knowledge on the substance and describes areas where further research is needed.

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.

Update November 23, 2008
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