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Reprod Toxicol. 2010 Jan;29(1):10-24. doi: 10.1016/j.reprotox.2009.10.006. Epub 2009 Oct 20.
Boron treatment of rats, mice, and dogs has been associated with testicular toxicity, characterized by inhibited spermiation at lower dose levels and a reduction in epididymal sperm count at higher dose levels. The no-adverse-effect level for reproductive effects in male rats is 17.5mg B/kg bw/day. Earlier studies in human workers and populations have not identified adverse effects of boron exposure on fertility, but outcome measures in these studies were relatively insensitive, based mainly on family size and did not include an evaluation of semen end points. A recent study of nearly 1000 men working in boron (B) mining or processing in Liaoning province in northeast China has been published in several Chinese and a few English language papers. This study included individual assessment of boron exposure, interview data on reproductive experience and semen analysis. Employed men living in the same community and in a remote community were used as controls. Boron workers (n=75) had a mean daily boron intake of 31.3mg B/day, and a subset of 16 of these men, employed at a plant where there was heavy boron contamination of the water supply, had an estimated mean daily boron intake of 125 mg B/day. Estimates of mean daily boron intake in local community and remote background controls were 4.25mg B/day and 1.40 mg/day, respectively. Reproductive outcomes in the wives of 945 boron workers were not significantly different from outcomes in the wives of 249 background control men after adjustment for potential confounders. There were no statistically significant differences in semen characteristics between exposure groups, including in the highly exposed subset, except that sperm Y:X ratio was reduced in boron workers. Within exposure groups the Y:X ratio did not correlate with the boron concentration in blood, semen and urine. In conclusion, while boron has been shown to adversely affect male reproduction in laboratory animals, there is no clear evidence of male reproductive effects attributable to boron in studies of highly exposed workers.
硼对大鼠、小鼠和狗的治疗与睾丸毒性有关，其特征是在较低剂量水平下抑制精子发生，在较高剂量水平下减少附睾精子计数。雄性大鼠生殖效应的无不良影响水平为 17.5mg B/kg bw/day。早期在人类工人和人群中的研究并未发现硼暴露对生育能力有不良影响，但这些研究中的结果衡量标准相对不敏感，主要基于家庭规模，并且不包括对精液终点的评估。最近在中国东北辽宁省硼（B）开采或加工中对近 1000 名男性进行的一项研究已在一些中文和一些英文论文中发表。该研究包括个体硼暴露评估、生殖经历访谈数据和精液分析。在同一社区和偏远社区工作的在职男性被用作对照。硼作业工人（n=75）的平均每日硼摄入量为 31.3mg B/day，其中 16 名工人在一个工厂工作，该工厂的供水受到严重硼污染，估计每日硼摄入量为 125mg B/day。当地社区和偏远背景对照的平均每日硼摄入量估计分别为 4.25mg B/day 和 1.40mg B/day。在调整潜在混杂因素后，945 名硼作业工人的妻子的生殖结果与 249 名背景对照工人的妻子的生殖结果没有显著差异。除了硼作业工人的精子 Y:X 比例降低外，在暴露组之间的精液特征没有统计学上的显著差异，包括高度暴露组。在暴露组内，Y:X 比例与血液、精液和尿液中的硼浓度没有相关性。总之，虽然硼已被证明在实验室动物中对雄性生殖有不良影响，但在对高度暴露工人的研究中，没有明确证据表明硼对雄性生殖有影响。
