| Acrylonitrile ( ACN ) is an important intermediary for the synthesis of a variety of industrial organic products. Little attention was paid to the toxicity effects of ACN on the reproductive systems, especially on males. In China, males are the major part of workers in those operations. The reproductive toxicity of ACN has to be considered as an important hazardous effect on exposed workers, particularly on males.In order to study male reproductive toxicity of ACN, epidemiological research and animal experiment in vivo and in vitro were conducted. In human study, the reproductive outcome of exposed male's wife and the alteration of male sexual hormone were investigated; In animals experiments, reproductive performance, morphology alteration, biochemical changes, expression of gene, and toxic effects on germ cells and on sex hormone were assayed; In vitro study, sertoli cell and spermatogonia of newt were applied to explore the potential toxic mechanism.Parti. Epidemiological investigationExposure assessment was performed in male workers. The results showed that 73.1 percent of the air ACN concentration data in the workplaces exceeded the national hygienic standard. The maximum concentration was 42.00mg/m3 and the maximum PEC-TWA was 19.12mg/m3. The concentrations in the polymer and spinning workshop were much higher than in the solvent workshop. The average estimated cumulative uptake of exposed workers was 69.09 g.The incidence of pregnancy complication in males' wives was higher than that in control group and the incidence of infertility and spontaneous abortion in the solvent workshop with the lowest concentration was significantly lower than those in other workshops (P<0.05). Spontaneous abortion incidence in couples both exposed to ACN was significantly higher than that in male only exposed to ACN.FSH was increased with aging and T was declined in the ACN exposed workersafter 40 years old (P<0.05). Following working age increased, it also tended to increase in FSH while T declined and estrogens increased. T in the workers working in the solvent workshop with the lowest air ACN concentration was higher than those in other workshops. Both serum FSH and T in exposed workers were declined with the increase of cumulative dose. When ACN uptake was over 50g, T was significantly decreased, and when dose over lOOg, both FSH and T were decreased significantly.Parti. Experimental Study in vivoMale Wistar rats were daily administrated ACN by gavage 5 times a week for 13 weeks at the dose of 0, 10, 20 and 40mg/kg body weight, respectively. Mating experiment was conducted, and then the sperms parameters and the activities of enzymes were detected. Male Sprague-Dawley rats were daily administrated ACN by intraperitoneal 5 times a week for 13 weeks at the dose of 0, 7.5, 15 and 30 mg/kg body weight, respectively. The activities of antioxidant enzyme, the levels of glutathione and malonaldehyde, the mRNA expressions of androgen binding protein (ABP) and inhibin gene, and histopathology in testes were observed. ACN at dose of 6, 12 and 24mg/kg body weight were administrated by gavage to ICR mice for 5 consecutive days, the rate of abnormal sperms and micronucleus in early spermatogenic cells was analyzed. The effects on pituitary-gonad axis were investigated through the sex hormones detection from mice and rats and uterotrophic activity test.The results showed that there was no significant difference in those detected enzymes of testis and epididymis. Mating experiment indicated that ACN has no effect on sexual function of rats, but a decrease in the number of live fetuses per litter (5.58) and an increase in the rate of embryonic absorption (19.66%) at dose of 40mg/kg b.w.Testicular impairment in rats was observed with dose increasing. ACN caused degeneration of seminiferous tubule, decrease in the number of spermatogenic cells and spermatozoa in the tubule. Furthermore, apoptosis, necrosis and abnormal nucleus were observed on primary spermatocytes.After 4 weeks of ACN treatment, the levels...
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