Effect of benzene, toluene, xylene on the semen quality of exposed workers

Objective To examine the effects on semen and sperm quality of workers afte r a short and long term exposure to benzene, toluene, and xylene. Methods The semen and blood of 24 married workers exposed to benzene, tolue ne, and xylene from shoemaking, spray painting, or paint manufacturing fact ories were collected. The concentration of benzene, toluene, and xylene in the blood and semen was determined by using headspace chromatographic metho d. Routine sperm test was carried out and acrosin activity detected. Results The results showed that benzene, toluene, and xylene were found in the blood and semen of some ex-workers in a working environment where the a ir concentration of benzene, toluene, and xylene exceeded the maximum allow able concentration (MAC) This result was not found in workers of the contro l group. There were also some effects on the quality of semen in the expose d workers. For example, the percentage of semen with liquefaction time exce eding 30 minutes increased. The sperm vitality, motility and acrosin activi ty decreased. At the same time, there were a positive correlation between l iquefaction time and the level of toluene in semen, and a negative correlat ion between sperm vitality, sperm activity or acrosin activity and working history. Conclusions The results suggested that the mixture could affect the quality of semen and sperm, which might be the main reason of the abnormal pregnan cy outcome among the wives of workers exposed to benzene, toluene, and xyle ne. Further studies are, however, required to confirm these findings.