Neurobehavioral effects of experimental exposures to low levels of styrene.

Two experimental studies were conducted with the intention to simulate exposure characteristics of work places with styrene exposure and to investigate the risk for neurobehavioral impairments. In experiment I 16 volunteers (8 in the morning, 8 in the afternoon) were exposed to 0.5 and 20 ppm styrene on a constant level for 3h. In experiment II 24 volunteers (12 in the morning, 12 in the afternoon) were exposed for 4h to 0.5 and 20 ppm styrene on a constant level as well as to a changing exposure between 0.5 and 40 ppm with a TWA of 14 ppm. Simple reaction, choice reaction, attention, acute symptoms, and ratings for well-being were measured. Exposure related performance effects could not be detected. However, 6h time change resulted in delayed choice reactions in the morning hours. Analysing acute symptoms and the state of well-being the impact of styrene did not reach adverse extents of impaired well-being.