Co-Carcinogenicity Of Foundry Particulates Silica And Silica Sand Substitutes, Volume 1, Final Report.
NIOSH 1984 Mar:188 pages
A carcinogenicity assay of silica (14808607) and silica sand substitutes was conducted. Male Syrian-Golden-hamsters were administered silica sand and 10 silica sand substitutes alone or with benzo(a)pyrene (50328) (BP) by intratracheal instillation weekly for 15 weeks. Doses ranged from 0.7 to 3.0 milligrams per 77 weeks. Moribund and all surviving animals were killed after 92 weeks. Complete necropsies were conducted. The silica and silica sand substitutes were not carcinogenic to the hamster respiratory tract. When given with BP, silica sand and the substitutes, except for an aluminum (7429905) silica formulation, caused a significantly higher incidence of respiratory tumors than BP alone. Malignant tumors were induced in all parts of the respiratory tract, and consisted primarily of adenocarcinomas, adenosquamous carcinomas, squamous cell carcinomas, and adenomas. Silica and the silica sand substitutes did not induce any fibrogenic activity in the lungs. No pathological changes were seen in any other organs. The authors conclude that silica and silica sand substitutes by themselves are not carcinogenic to the hamster respiratory tract. When instilled with BP, they show a definite cocarcinogenic response.
NIOSH-Contract; Industrial-exposures; Animal-studies; Carcinogenicity; Airborne-particles; Foundry-sands; Silica-dusts; Tumorigens; Histopathology; Mortality-data; Contract-210-79-0036;
14808-60-7; 50-32-8; 7429-90-5;
NTIS Accession No.
Division of Biomedical and Behavioral Science, NIOSH, U.S. Department of Health and Human Services, Cincinnati, Ohio