[Development of tumors in Unio pictorum bivalve mollusks under the influence of N-nitroso compounds].

Diethyl- and dimethylnitrosamines dissolved in tank water in doses of 200-400 ppm induced neoplasms of the digestive gland (basophilic cell neoplasms) in 16 of 95 and in 6 of 17 molusco which survived to the time of appearance of the first tumour (38-39 days), and also neoplasms of the hemopoietic system (lymphatic leukemia) in 7 and 1 molluscs, chiefly in combination with tumours of the digestive gland. Methylnitrosoguanidine induced only inflammatory changes at the site of injections. It is of expedience to use the molluscs as a biological indicator of the hydrosphere pollution with chemical carcinogens.