CARCINOGENICITY TESTING OF CHEMICALS

Prediction of the carcinogenicity of a second group of organic chemicals undergoing carcinogenicity testing.

Twenty-four organic compounds currently undergoing testing within cancer bioassays under the aegis of the U.S. National Toxicology Program (NTP) were submitted to the computer automated structure evaluation (CASE) and multiple computer automated structure evaluation (MULTICASE) system for predictions of activity. Individual predictions resulting from the NTP combined rodent, NTP mouse, Carcinog...

Guidelines for the testing of chemicals for carcinogenicity. Committee on Carcinogenicity of Chemicals in Food, Consumer Products and the Environment.

Chapter 1 gives some background information on general issues in chemical carcinogenesis. It briefly discusses mechanisms by which genotoxic and nongenotoxic substances may be involved in the development of cancer. The role of oncogenes and tumour-suppressor genes in molecular carcinogenesis is also described. The contribution from epidemiological studies to the overall assessment is dealt with...

Carcinogenicity of multiple chemicals simultaneously administered.

The possibility that several carcinogens may act concurrently in organs such as the lungs and skin has assumed greater importance as the nec ognized possible agents increase for these sites. A wide range of effects, from inhibition through no effects to summation or even synergism must be considered. The dosage, type of agents, portal of entry, duration of exposure, site and type of tissue, spe...

Prediction of rodent carcinogenicity for 30 chemicals.

Predictions of carcinogenic activity are made for 30 chemicals currently being assessed for rodent carcinogenicity by the U.S. National Toxicology Program. The predictions are based upon the chemical structure, the anticipated or reported mutagenicity, and the reported sub-chronic toxicity of each chemical. It is predicted that 13 chemicals will be noncarcinogenic to rodents, that 7 will be gen...

Procedures for screening chemicals for carcinogenicity.