Safety evaluation of a male injectable antifertility agent, styrene maleic anhydride, in rats.

Injection of a polymer, styrene maleic anhydride (SMA), into the lumen of the vas deferens of rats, was observed to have effective and reversible contraception. The safety evaluation of the polymer, for 90 days, was carried out in Charles Foster male rats. There have been no significant changes in any of the toxicity parameters in the test animals as compared to the control animals. Hence, it is concluded that the compound is non-toxic to rodents.