title: Tumor induction by N-nitroso compounds in bivalve mollusks Unio pictorum.
abstract: Diethylnitrosamine (DENA) and dimethylnitrosamine (DMNA) dissolved in tank water induced neoplasms in bivalve mollusks Unio pictorum. DENA induced tumors in 18% of the animals exposed to 200 ppm and 68% of those exposed to 400 ppm; average latent periods were 71 and 61 days, respectively. DMNA induced tumors in 8% of the animals exposed to 200 ppm for 51 days and 27% of those exposed for 152 days with average latent periods of 85 and 81 days, respectively. Neoplasms were observed in the digestive gland (basophilic cell tumors; 38 cases), the hemopoietic system (hemocytoblastosis; 12 cases) and the kidney (poorly differentiated carcinoma; 1 case). It is expedient to use mollusks, both for testing of N-nitroso compounds and as a biologic indicator of hydrospheric pollution.
mesh_terms: D000818:Animals; D004052:Diethylnitrosamine / Q000633:toxicity; D004128:Dimethylnitrosamine / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical / Q000379:methods; D008974:Mollusca; D009374:Neoplasms, Experimental / Q000139:chemically induced*; D009602:Nitrosamines / Q000633:toxicity*; D013997:Time Factors
chemical_list: D009602:Nitrosamines; D004052:Diethylnitrosamine; D004128:Dimethylnitrosamine