Giwercman Aleksander, Rylander Lars, Lundberg Giwercman Yvonne
Reproductive Medicine Centre and Molecular Reproductive Research Group, Lund University, Malmö University Hospital, SE 205 02 Malmö, Sweden.
Reprod Biomed Online. 2007 Dec;15(6):633-42. doi: 10.1016/s1472-6483(10)60530-5.
It has been suggested that during the past five decades human sperm counts have declined and the incidence of testicular cancer, hypospadias and cryptorchidism has increased. Furthermore, geographical differences, with respect to these markers of male reproductive function, have been reported. According to a recent hypothesis, all these abnormalities of the male genital system do have a common cause, namely exposure to endocrine disruptors affecting the male in early fetal life. Reduced sperm production as well as congenital abnormalities of male genitalia can be evoked in laboratory animals by exposing them to chemicals with endocrine-disrupting effect, and in humans similar effects have been seen following accidental exposures to very high concentrations of these environmental toxicants. However, the evidence for association between levels of exposure found in the general population and serious adverse effects on male reproduction, including fertility, is still lacking. A recent European Union-supported study, on the effect of persistent organohalogen pollutants on human reproduction, failed to show any correlation between post-natal exposure levels and fertility. Future studies will reveal whether prenatal exposure does more strongly affect male fertility and whether genetic predisposition regulates the susceptibility of an individual to the adverse effects of endocrine disruptors.
有人认为，在过去的五十年里，人类精子数量下降，睾丸癌、尿道下裂和隐睾症的发病率上升。此外，关于男性生殖功能的这些指标，也有地理差异的报道。根据最近的一种假说，男性生殖系统的所有这些异常都有一个共同的原因，即胎儿早期接触影响男性的内分泌干扰物。通过让实验动物接触具有内分泌干扰作用的化学物质，可以引起精子生成减少以及男性生殖器的先天性异常，在人类中，意外接触非常高浓度的这些环境毒物后也观察到了类似的影响。然而，仍然缺乏证据表明一般人群中发现的接触水平与对男性生殖（包括生育能力）的严重不良影响之间存在关联。最近一项由欧盟支持的关于持久性有机卤素污染物对人类生殖影响的研究，未能显示出生后接触水平与生育能力之间有任何关联。未来的研究将揭示产前接触是否对男性生育能力有更强的影响，以及遗传易感性是否调节个体对内分泌干扰物不良影响的易感性。
