Actinolite
One of the six types of asbestos.

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.

Vermiculite
A chemically inert, lightweight, fire resistant, and odorless magnesium silicate material that is generally used for its thermal and sound insulation in construction and for its absorbent properties in horticultural applications. Vermiculite mined from Libby, Montana has been demonstrated to contain various amounts of asbestiform tremolite-like amphibole minerals.

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

Serpentine
In the asbestos varieties, the brucite and silicate layers bend into tubers that produce the fibers. Chrysotile asbestos is a fibrous member of the serpentine group. "Serpentine" comes from mottled shades of green on massive varieties, suggestive of snake markings.

Mesothelioma
A rare malignant tumor of the lung membrane which lines the chest and abdominal cavity. Malignant mesothelioma is a cancerous tumor of the pleura (lining of the lung and chest cavity) or peritoneum (lining of the abdomen) that is almost always caused by sustained exposure to asbestos.

Laparotomy
Abdominal exploration is a type of surgery where the abdomen is opened (laparotomy) and explored (exploratory laparotomy) for examination and treatment of problems. Might be used in relation to asbestos disease problems.

Asbestosis
A progressively restrictive fibrosis of the lung and is recognized as a disabling and fatal occupational disease.

RACM
Regulated Asbestos-Containing Material is (a) friable asbestos material, (b) Category I non-friable ACM that has become friable, (c) Category I non-friable ACM that will be or has been subjected to sanding, grinding, cutting or abrading, or (d) Category II non-friable ACM that has a high probability of becoming or has become crumbled, pulverized, or reduced to powder by the forces expected to act on the material in the course of demolition or renovation operations.

Lethal Concentration(50) (LC50)
A calculated concentration of a chemical in air to which exposure for a specific length of time is expected to cause death in 50% of a defined experimental animal population.