The styrene metabolite, phenylglyoxylic acid, induces striatal-motor toxicity in the rat: influence of dose escalation/reduction over time.

Exposure to the industrial solvent, styrene, induces locomotor and cognitive dysfunction in rats, and parkinsonian-like manifestations in man. The antipsychotic, haloperidol (HP), well known to induce striatal toxicity in man and animals, and styrene share a common metabolic pathway yielding p-fluoro phenylglyoxylic acid and phenylglyoxylic acid (PGA), respectively. Using an exposure period of 30 days and the vacous chewing movement (VCM) model as an expression of striatal-motor toxicity, we found that incremental PGA dosing (220-400 mg/kg) significantly increased VCMs up to day 25, but decreased to control levels shortly after reaching maximum dose.