PERIPHERAL NEUROPATHY IN STYRENE-EXPOSED WORKERS

Background The toxicity of styrene on the peripheral nervous system is still debated. Cases The paper presents two cases of peripheral senso rimotor neuropathy in styrene-exposed workers. Exposure, evaluated by biological monitoring, ranged between 100 and 150% of the current limi ts proposed by the American Conference of Governmental Industrial Hygi enists (ACGM). The subjects complained of leg weakness and numbness, c ramps, and paresthesia. Electrophysiology revealed a moderate peripher al sensorimotor neuropathy of a demyelinating type. Color-vision testi ng showed a subclinical deficit. Common inherited and acquired causes of peripheral neuropathy and dyschromatopsia other than styrene were r uled out by personal history, medical examination, laboratory data, an d chest X-ray. Conclusions The results suggest that long-term occupati onal exposure to environmental levels of styrene that are equal, or sl ightly above, the ACGM limits can induce a clinical form of peripheral neuropathy and a subclinical impairment of color vision. As a consequ ence, a careful reappraisal of the real preventive meaning of the curr ent ACGM occupational limit for styrene, at least on an individual bas is, is needed.