Wang Yi-Xin, Sun Yang, Feng Wei, Wang Peng, Yang Pan, Li Jin, Huang Zhen, Chen Ying-Jun, Liu Chong, Sun Li, Yue Jing, Gu Long-Jie, Zeng Qiang, Lu Wen-Qing
Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China; Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental health (incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China.
Department of biostatistics, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, Guangdong, PR China.
Environ Int. 2016 May;91:51-9. doi: 10.1016/j.envint.2016.02.019. Epub 2016 Feb 22.
Exposure to metals, including essential and nonessential elements, has been linked to male reproductive health in animals. However, findings from human studies are inconsistent.
To examine the associations between metal exposure at environmental levels and semen quality in a Chinese population by performing repeated measurements of urinary metals to estimate individual-level exposure.
From March to June 2013, 1052 men seeking semen evaluation were recruited from the Reproductive Center of Tongji Hospital in Wuhan, China. Each man provided one semen sample and two urine sample. Semen quality parameters and urinary levels of 18 metals were determined. Associations between the urinary metal levels and semen quality parameters were assessed using confounder adjusted linear and logistic regressions. Restricted cubic spline analysis was performed to assess dose-response relationships between continuous metal measurements and outcomes.
Urinary levels of cadmium were significantly inversely associated with progressive sperm motility and total motility (both P<0.02) based on multivariable linear regression models, consistent with the trends of increased odds ratios for below-reference semen quality parameters observed in the logistic models (both P<0.05). Additionally, we found significant inverse associations of urinary molybdenum and lead with percentages of normal sperm morphology (both P<0.05). These associations remained suggestive or significant after adjustment for multiple testing. They were also robust to the simultaneous consideration of multiple metals, and curves of restricted cubic spline showed clear dose-response relationships.
Our findings suggest that environmental exposure to cadmium, molybdenum and lead may contribute to a decline in human semen quality.
接触金属，包括必需元素和非必需元素，已被证明与动物的雄性生殖健康有关。然而，人体研究的结果并不一致。
通过对尿金属进行重复测量以估计个体水平的暴露，研究中国人群环境水平的金属暴露与精液质量之间的关联。
2013年3月至6月，从中国武汉同济医院生殖中心招募了1052名寻求精液评估的男性。每位男性提供一份精液样本和两份尿液样本。测定精液质量参数和18种金属的尿水平。使用混杂因素调整的线性和逻辑回归评估尿金属水平与精液质量参数之间的关联。进行受限立方样条分析以评估连续金属测量与结果之间的剂量反应关系。
基于多变量线性回归模型，尿镉水平与进行性精子活力和总活力均呈显著负相关（均P<0.02），这与逻辑模型中观察到的低于参考精液质量参数的比值比增加趋势一致（均P<0.05）。此外，我们发现尿钼和铅与正常精子形态百分比呈显著负相关（均P<0.05）。在进行多重检验校正后，这些关联仍然具有提示性或显著性。它们在同时考虑多种金属时也很稳健，受限立方样条曲线显示出明确的剂量反应关系。
我们的研究结果表明，环境中镉、钼和铅的暴露可能导致人类精液质量下降。
