Preclinical toxicity study of a male injectable antifertility agent (styrene maleic anhydride) in rhesus monkeys, Macaca mulatta.

Polymer styrene maleic anhydride dissolved in dimethyl sulphoxide was injected intravasally to rhesus monkeys at the dose levels of 100 mg, 250 mg, and 500 mg in each vas deferens in low, high, and highest dose groups respectively, while control group received 0.5 ml DMSO in each vas deferens. The systemic toxicity study of the implant was carried out for 90 d. There had been no alteration in any of the toxicity parameters, ie, body weight, haematological, biochemical or histopathological, in the test animals as compared to control animals. Hence, it is concluded that the polymer SMA injected at above doses appears to be safe in our experiment.