The behavioral toxicity of a tributyltin ester in the rat.

The behavioral toxicity of an organic tin compound under consideration for use in marine antifouling paint was assessed using a Sidman avoidance paradigm. The assessed compound, an organometallic polymer (tributyltin [methacrylic-CO-methylmethacrylate] ester), is from a group of alkyltin compounds of which triethyl and tributyltin are known to be toxic. Rats were tested under a free-operant avoidance procedure for 6 months while ingesting the polymer in their drinking water. At the beginning of the 5th month significant behavioral changes became evident, reflected in increases in shock rate, decreased responding, and a shifting of the interresponse time distribution. Performance improved upon withdrawal of the contaminant suggesting that limited exposure to the polymer may not result in permanent behavioral dysfunction.