Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI, 48109, United States.
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, 80309, United States.
Water Res. 2020 Mar 1;170:115325. doi: 10.1016/j.watres.2019.115325. Epub 2019 Nov 19.
Arsenic field test kits are widely used to measure arsenic levels in drinking water sources, especially in countries like Bangladesh, where water supply is highly decentralized and water quality testing infrastructure is limited. From a public health perspective, the ability of a measurement technique to distinguish samples above and below relevant and actionable drinking water standards is paramount. In this study, the performance of eight commercially available field test kits was assessed by comparing kit estimates to hydride generation atomic absorption spectroscopy (HG-AAS) analyses. The results of tests that control for user-dependent color matching errors showed that two kits (LaMotte and Quick II kits) provided accurate and precise estimates of arsenic, four kits (Econo-Quick, Quick, Wagtech and Merck kits) were either accurate or precise, but not both, and two kits (Hach and Econo-Quick II kits) were neither accurate nor precise. Tests were performed for arsenic concentration ranges commonly found in natural waters and treated waters (such as community drinking water filter systems), and also on laboratory generated arsenic standards in DI water. For those kits that did not perform well, test strips often produced colors too light compared to manufacturer-provided arsenic color calibration charts. Based on these results, we recommend stakeholders carefully re-consider the use of poorly performing field test kits until better quality control of components of these kits is implemented. In addition, we recommend that field test kit manufacturers provide suitable internal standards in every kit box for users to verify the veracity of manufacturer provided color charts.
砷现场测试包广泛用于测量饮用水源中的砷含量，特别是在孟加拉国等国家，那里的供水高度分散，水质测试基础设施有限。从公共卫生的角度来看，测量技术能够区分相关和可操作的饮用水标准以上和以下的样本是至关重要的。在这项研究中，通过将试剂盒的估计值与氢化物发生原子吸收光谱法（HG-AAS）分析进行比较，评估了八种市售现场测试包的性能。在控制用户依赖的颜色匹配误差的测试结果表明，两种试剂盒（LaMotte 和 Quick II 试剂盒）能够准确而精确地估计砷，四种试剂盒（Econo-Quick、Quick、Wagtech 和 Merck 试剂盒）要么准确要么精确，但不能两者兼而有之，两种试剂盒（Hach 和 Econo-Quick II 试剂盒）既不准确也不精确。测试是在天然水和处理水（如社区饮用水过滤系统）中常见的砷浓度范围内以及在 DI 水中生成的实验室砷标准品上进行的。对于那些表现不佳的试剂盒，测试条与制造商提供的砷颜色校准图表相比，颜色往往太浅。基于这些结果，我们建议利益相关者在实施这些试剂盒的组件更好的质量控制之前，重新仔细考虑使用性能不佳的现场测试试剂盒。此外，我们建议现场测试试剂盒制造商在每个试剂盒中提供适当的内部标准，供用户验证制造商提供的颜色图表的真实性。
