Qatar Environment and Energy Research Institute (QEERI), Qatar Foundation, P.O. Box 5825, Doha, Qatar.
Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA.
Environ Res. 2014 May;131:86-94. doi: 10.1016/j.envres.2014.02.011. Epub 2014 Mar 25.
Qatar׳s farm workers provide a unique population for exposure study: they are young, healthy males. This study combined trace element profiles in urine and toenail with survey information from 239 farm workers to assess the extent to which the biomarkers provide complementary exposure information. Urinary Mo levels (average=114 µg/L) were elevated; average urinary values (µg/L) for all other elements were: V (1.02), Cr (0.55), Mn (2.15), Fe (34.1), Co (0.47), Ni (2.95), Cu (15.0), As (47.8), Se (25.7), Cd (1.09), Ba (22.5), Pb (2.50) and U (0.15). Average toenail concentrations (mg/kg) were: Mn (2.48), Cu (4.43), As (0.26), Se (0.58), Mo (0.07), Cd (0.03), Ba (1.00), Pb (0.51) and U (0.02). No significant association was found between corresponding elements in urine and toenails. Elemental profiles suggest groundwater (with the exception of Mo) and soil-dust-crop exposure pathways cannot account for elemental variations. The main factors moderating trace element contents are related to depuration processes involving participants׳ trace element body burden prior to work in Qatar, and interactions of trace element metabolic cycles which over-ride the exposure footprint. Toenail and urine need to be carefully validated before reliable use as biomarkers of exposure in general populations for most elements in the study.
他们是年轻、健康的男性。本研究将尿液和趾甲中的微量元素谱与 239 名农场工人的调查信息相结合，以评估生物标志物在多大程度上提供了补充暴露信息。尿钼水平（平均值=114μg/L）升高；所有其他元素的尿液平均值（μg/L）为：V（1.02）、Cr（0.55）、Mn（2.15）、Fe（34.1）、Co（0.47）、Ni（2.95）、Cu（15.0）、As（47.8）、Se（25.7）、Cd（1.09）、Ba（22.5）、Pb（2.50）和 U（0.15）。趾甲的平均浓度（mg/kg）为：Mn（2.48）、Cu（4.43）、As（0.26）、Se（0.58）、Mo（0.07）、Cd（0.03）、Ba（1.00）、Pb（0.51）和 U（0.02）。尿液和趾甲中相应元素之间没有发现显著关联。元素谱表明，地下水（除了 Mo）和土壤-尘埃-作物暴露途径不能解释元素的变化。调节微量元素含量的主要因素与参与者在卡塔尔工作前体内微量元素负担的净化过程有关，以及微量元素代谢循环的相互作用，这些循环覆盖了暴露足迹。在将趾甲和尿液作为研究中大多数元素的一般人群暴露生物标志物进行可靠使用之前，需要仔细验证。
