Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27709, USA.
Environ Res. 2013 Oct;126:134-44. doi: 10.1016/j.envres.2013.04.004. Epub 2013 Jun 15.
Although consumption of drinking water contaminated with inorganic arsenic is usually considered the primary exposure route, aggregate exposure to arsenic depends on direct consumption of water, use of water in food preparation, and the presence in arsenicals in foods. To gain insight into the effects of biological and behavioral factors on arsenic exposure, we determined arsenic concentrations in urine and toenails in a U.S. population that uses public or private water supplies containing inorganic arsenic. Study participants were 904 adult residents of Churchill County, Nevada, whose home tap water supplies contained <3 to about 1200 µg of arsenic per liter. Biomarkers of exposure for this study were summed urinary concentrations of inorganic arsenic and its methylated metabolites (speciated arsenical), of all urinary arsenicals (total arsenical), and of all toenail arsenicals (total arsenical). Increased tap water arsenic concentration and consumption were associated with significant upward trends for urinary speciated and total and toenail total arsenical concentrations. Significant gender differences in concentrations of speciated and total arsenicals in urine and toenails reflected male-female difference in water intake. Both recent and higher habitual seafood consumption significantly increased urinary total but not speciated arsenical concentration. In a stepwise general linear model, seafood consumption significantly predicted urinary total arsenical but not urinary speciated or toenail total arsenical concentrations. Smoking behavior significantly predicted urinary speciated or total arsenical concentration. Gender, tap water arsenic concentration, and primary drinking water source significantly predicted urinary speciated and total concentrations and toenail total arsenical concentrations. These findings confirm the primacy of home tap water as a determinant of arsenic concentration in urine and toenails. However, biological and behavioral factors can modify exposure-response relations for these biomarkers. Refining estimates of the influence of these factors will permit better models of dose-response relations for this important environmental contaminant.
尽管饮用受无机砷污染的水通常被认为是主要的暴露途径，但砷的总暴露量取决于直接饮用水、食品制备用水以及食品中砷剂的存在。为了深入了解生物和行为因素对砷暴露的影响，我们测定了美国一个使用含无机砷公共或私人供水的人群尿液和趾甲中的砷浓度。研究对象为内华达州丘吉尔县的 904 名成年居民，他们家中的自来水供应中砷含量为每升<3 至约 1200μg。本研究的暴露生物标志物为无机砷及其甲基化代谢物（特定砷化物）、所有尿液砷化物（总砷化物）和所有趾甲砷化物（总砷化物）的总和。自来水中砷浓度的增加和摄入量的增加与尿液中特定和总砷化物以及趾甲中总砷化物浓度的显著上升趋势有关。尿液中特定和总砷化物浓度的显著性别差异反映了男女在饮水量上的差异。最近和更高的习惯性海鲜消费显著增加了尿液中的总砷含量，但不增加特定砷化物的浓度。在逐步一般线性模型中，海鲜消费显著预测了尿液中的总砷含量，但不预测尿液中的特定或趾甲中的总砷含量。吸烟行为显著预测了尿液中的特定或总砷化物浓度。性别、自来水中的砷浓度和主要饮用水源显著预测了尿液中的特定和总浓度以及趾甲中的总砷含量。这些发现证实了家庭自来水是决定尿液和趾甲中砷浓度的主要因素。然而，生物和行为因素可以改变这些生物标志物的暴露-反应关系。细化这些因素的影响估计将使该重要环境污染物的剂量-反应关系模型得到更好的改进。
