Walker Mark, Fosbury DeEtta
Department of Natural Resources and Environmental Sciences, University of Nevada, Reno, NV 89557-0013, USA.
J Water Health. 2009 Jun;7(2):293-301. doi: 10.2166/wh.2009.024.
In parts of the western United States groundwater used for drinking water contains high concentrations of metals, including arsenic. In a rural county in Nevada, USA, we measured concentrations of arsenic and tungsten and the proportion of arsenic occurring in trivalent form (As((III))) in tap water samples from private domestic wells in 307 households. The proportion of arsenic occurring as As((III)) ranged from 0 to 100% (ave. 21%, median 1%). Tungsten concentrations ranged from 0 to 610 microg l(-1) (ave. 26 microg l(-1), median 2 microg l(-1)). Among 253 respondents who consumed water: (a) 177/253 (70%) of tap water samples contained more than 10 microg l(-1) total inorganic arsenic (ave. 66 microg l(-1), median 20 microg l(-1)); (b) As((III)) occurred as a small proportion of total arsenic in most samples (ave. 22%, median 3%); and (c) tungsten occurred in concentrations ranging from below the detection limit (3 microg l(-1)) to a maximum of 610 microg l(-1) (ave. 30 microg l(-1), median 3 microg l(-1)). Log(10) concentrations of tungsten and total arsenic in consumed water were positively correlated (log(10)[W] = -0.400 + 0.703(log(10)[As(T)]), p = 0.000+, adj. r(2) = 0.53). This suggests that householders in this area were likely to be exposed to both metals simultaneously, given that 253/307 of the respondents (82%) reported consuming tap water.
在美国西部部分地区，用于饮用水的地下水中含有高浓度金属，包括砷。在美国内华达州的一个乡村县，我们测量了307户家庭自备水井的自来水样本中砷和钨的浓度以及三价砷（As(III)）占砷的比例。As(III)占砷的比例范围为0至100%（平均21%，中位数1%）。钨浓度范围为0至610微克/升（平均26微克/升，中位数2微克/升）。在253名饮用水受访者中：（a）177/253（70%）的自来水样本中总无机砷含量超过10微克/升（平均66微克/升，中位数20微克/升）；（b）在大多数样本中，As(III)占总砷的比例较小（平均22%，中位数3%）；（c）钨的浓度范围从低于检测限（3微克/升）到最高610微克/升（平均30微克/升，中位数3微克/升）。饮用水中钨和总砷的log(10)浓度呈正相关（log(10)[W] = -0.400 + 0.703(log(10)[As(T)])，p = 0.000+，调整后r(2) = 0.53）。这表明该地区的家庭住户可能同时接触到这两种金属，因为253/307的受访者（82%）报告饮用自来水。
