Dose-Response Relationship
The quantitative relationship between the amount of exposure to a toxicant and the incidence of the adverse effects.

Immediately Dangerous to Life or Health (IDLH)
The maximum environmental concentration of a contaminant from which one could escape within 30 minutes without any escape-impairing symptoms or irreversible health effects.

Pericardial mesothelioma
Pericardial mesothelioma is a highly lethal and fortunately rare cardiac neoplasm

Hazardous Air Pollutants
Air pollutants that are not covered by ambient air quality standards but which, as defined in the Clean Air Act, may reasonably be expected to cause or contribute to irreversible illness or death. Such pollutants include asbestos, beryllium, mercury, benzene, coke oven emissions, radionuclides, and vinyl chloride.

Actinolite
Actinolite is the intermediate member; when iron is predominant the mineral is ferro-actinolite and when magnesium is predominant, the mineral is tremolite. The iron produces a green color that darkens as the iron content increases. Actinolite may occur in fibrous form (an asbestos). It is not used commercially, but is a common impurity in chrysotile asbestos.

Amosite
A type of asbestos in the amphibole group; it is also known as brown asbestos.

Intermediate Exposure
Exposure to a chemical for a duration of 15-364 days, as specified in the Toxicological Profiles.

Parenchymal fibrosis
It is easily conceivable that prolonged retention of some types of minerals in the lung would be a stimulating factor for inflammatory and neoplastic processes, leading in turn to parenchymal fibrosis and peripheral cancer.

Minimal Risk Level (MRL)
An estimate of daily human exposure to a hazardous substance that is likely to be without an appreciable risk of adverse noncancer health effects over a specified route and duration of exposure.

Bulk Sample
A sample of suspected asbestos-containing material that is obtained from a building to be analyzed microscopically for asbestos content. Bulk sample analysis can be part of a process to assess the hazard from asbestos in a building.