Effectiveness and Reliability of Arsenic Field Testing Kits: Are the Million Dollar Screening Projects Effective or Not?
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- 作者：Mohammad Mahmudur Rahman ; Debapriyo Mukherjee ; Mrinal Kumar Sengupta ; Uttam Kumar Chowdhury ; Dilip Lodh ; Chitta Ranjan Chanda ; Shibtosh Roy ; Md. Selim ; Quazi Quamruzzaman ; Abul Hasnat Milton ; S. M. Sh
- 刊名：Environmental Science & Technology
- 出版年：2002
- 出版时间：December 15, 2002
- 年：2002
- 卷：36
- 期：24
- 页码：5385 - 5394
- 全文大小：793K
- 年卷期：v.36,no.24(December 15, 2002)
- ISSN：1520-5851
文摘
The exposure of millions to arsenic contaminated waterfrom hand tube wells is a major concern in many Asiaticcountries. Field kits are currently used to classify tube wellsas delivering arsenic below 50 
g/L (the recommendedlimit in developing countries) as safe, painted green or above50 g/L, unsafe and painted red. More than 1.3 milliontube wells in Bangladesh alone have been tested by fieldkits. A few million U.S. dollars have already been spentand millions are waiting for the ongoing projects. However,the reliability of the data generated through field kits isnow being questioned. Samples from 290 wells were testedby field kits and by a reliable laboratory technique toascertain the reliability of field kits. False negatives wereas high as 68% and false positives up to 35%. A statisticalanalysis of data from 240 and 394 other wells yielded similarrates. We then analyzed 2866 samples from previouslylabeled wells and found 44.9% mislabeling in the lower range(<50 g/L) although mislabeling was considerablyreduced in the higher range. Variation of analyticalresults due to analysts and replicates were pointed outadopting analysis of variance (ANOVA) technique. Millionsof dollars are being spent without scientific validation ofthe field kit method. Facts and figures demand improved,environmentally friendly laboratory techniques to producereliable data.
g/L (the recommendedlimit in developing countries) as safe, painted green or above50 g/L, unsafe and painted red. More than 1.3 milliontube wells in Bangladesh alone have been tested by fieldkits. A few million U.S. dollars have already been spentand millions are waiting for the ongoing projects. However,the reliability of the data generated through field kits isnow being questioned. Samples from 290 wells were testedby field kits and by a reliable laboratory technique toascertain the reliability of field kits. False negatives wereas high as 68% and false positives up to 35%. A statisticalanalysis of data from 240 and 394 other wells yielded similarrates. We then analyzed 2866 samples from previouslylabeled wells and found 44.9% mislabeling in the lower range(<50 g/L) although mislabeling was considerablyreduced in the higher range. Variation of analyticalresults due to analysts and replicates were pointed outadopting analysis of variance (ANOVA) technique. Millionsof dollars are being spent without scientific validation ofthe field kit method. Facts and figures demand improved,environmentally friendly laboratory techniques to producereliable data.