MODELING THE ACUTE NEUROTOXICITY OF STYRENE

Styrene is a widely used industrial solvent associated with acute neur otoxicity. To investigate the relationships between exposure, blood co ncentrations, and the appearance of neurotoxic effects, four healthy m ales were exposed to styrene concentrations of 5-200 ppm in four diffe rent exposure-time profiles, A digit recognition test and P300 event-r elated evoked potential were used to measure neurologic function. A ph ysiologically based Kinetic (PBK) model generated close predictions of measured styrene blood concentrations, in the range of 0.01-12 mg/L, from this and 21 previous studies. Simulated peak brain concentration, durationxaverage exposure, and peak exposure level were predictive of toxicity, Central nervous system effects were expected at a blood con centration near 2.4 mg/L. A standard of 20 ppm was expected to protect styrene-exposed workers from acute central nervous system toxicity un der light work conditions.