Sperm chromatin structure and semen quality following occupational styrene exposure

Abstract

~uppl1:70-73. Key terms epidemiology, genotoxicity, occupational exposure, spermatozoa, sperm count. Occupational exposure to organic solvents may exert a detrimental effect on human spermiogenesis (1, 2). But the findings are not conclusive (3, 4). Styrene is an or- ganic solvent used for the production of plastics. It has a well documented neurotoxic effect and may modulate dopamine metabolism in the brain and disturb the pitui- tary-gonadal axis. An increased proportion of spesm with abnormal morphology has been reported for workers ex- posed to high levels of styrene (5). Some studies of ro- dents have indicated decreased sperm count following styrene exposure (6), while others have not (7). In the reinforced plastics industry, workers may be exposed to high styrene levels, while other exposures sus- pected to be hazardous to spermatogenesis are absent. Styrene, therefore, was selected as an organic solvent suitable for a further assessment of effects on human spermiogenesis. In this study, 23 workers provided a semen sample at the time of being hired in the reinforced plastics indus- try and again after about 6 months of employment. Changes in conventional measures of semen quality and sperm susceptibility to denaturation, as assessed by the flow cytometric sperm chromatin structure assay (SCSA), were related to levels of styrene exposure.