The University of Zambia, School of Veterinary Medicine, P.O. Box 32379, Lusaka, Zambia.
Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan.
Chemosphere. 2018 Jul;202:48-55. doi: 10.1016/j.chemosphere.2018.03.079. Epub 2018 Mar 12.
Lead (Pb) and cadmium (Cd) are toxic metals that exist ubiquitously in the environment. Children in polluted areas are particularly vulnerable to metal exposure, where clinical signs and symptoms could be nonspecific. Absorbed metals are excreted primarily in urine and reflect exposure from all sources. We analyzed Pb and Cd concentrations in blood, feces and urine of children from polluted townships near a lead-zinc mine in Kabwe, Zambia, to determine concurrent childhood exposure to the metals. Moreover, the study determined the Pb and Cd relationships among urine, feces and blood as well as accessed the potential of urine and fecal analysis for biomonitoring of Pb and Cd exposure in children. Fecal Pb (up to 2252 mg/kg, dry weight) and urine Pb (up to 2914 μg/L) were extremely high. Concentrations of Cd in blood (Cd-B) of up to 7.7 μg/L, fecal (up to 4.49 mg/kg, dry weight) and urine (up to 18.1 μg/L) samples were elevated. metal levels were higher in younger children (0-3 years old) than older children (4-7). Positive correlations were recorded for Pb and Cd among blood, urine and fecal samples whereas negative correlations were recorded with age. These findings indicate children are exposed to both metals at their current home environment. Moreover, urine and feces could be useful for biomonitoring of metals due to their strong relationships with blood levels. There is need to conduct a clinical evaluation of the affected children to fully appreciate the health impact of these metal exposure.
铅(Pb)和镉(Cd)是存在于环境中的有毒金属。受污染地区的儿童特别容易受到金属暴露的影响,其临床症状和体征可能是非特异性的。吸收的金属主要通过尿液排泄,反映了来自所有来源的暴露。我们分析了赞比亚卡布韦附近一个铅锌矿污染乡镇儿童的血液、粪便和尿液中的 Pb 和 Cd 浓度,以确定儿童同时接触这些金属的情况。此外,该研究还确定了尿液、粪便和血液中 Pb 和 Cd 的关系,并评估了尿液和粪便分析在儿童 Pb 和 Cd 暴露生物监测中的潜力。粪便中的 Pb(高达 2252mg/kg,干重)和尿液中的 Pb(高达 2914μg/L)含量极高。血液(Cd-B)、粪便(高达 4.49mg/kg,干重)和尿液(高达 18.1μg/L)中的 Cd 浓度也升高。0-3 岁的儿童体内金属水平高于 4-7 岁的儿童。血液、尿液和粪便样本中 Pb 和 Cd 之间存在正相关,而与年龄呈负相关。这些发现表明,儿童在当前的家庭环境中同时接触到这两种金属。此外,由于尿液和粪便与血液水平之间存在较强的关系,因此它们可用于金属的生物监测。有必要对受影响的儿童进行临床评估,以充分了解这些金属暴露对健康的影响。