Carcinogenic risk assessment of arsenic poisoning in Bangladesh and ingestion of organo-arsenic in Japan.

本研究的目的是研究当前井水砷含量与尿砷浓度之间的关系，以检验孟加拉国缓解方案的有效性。2005年5月至7月在孟加拉国的帕布纳区进行了一项以社区为基础的横断面研究。我们包括174对已婚夫妇，并从138口井中收集他们的饮用水。326例受试者中有304例尿砷超标40μg/1.5L/d。其中，23.1%的井砷含量为50 μg/L。11 ~ 50 μg/L井水与【≤10 μg/L】井水中砷含量的多重校正比值比为8.90 (95% CI: 3.31 ~ 23.93)， 51.332 μg/L与【≤10 μg/L】的多校正比值比为53.07（11.91 ~ 236.46）。这些结果表明，孟加拉国政府认为安全的井水砷含量为11.50 μg/L并不安全。我们使用HPLC-ICP-MS对210名无职业接触的日本男性受试者进行了尿砷的形态分析。尿砷中位数为：亚砷酸钠（AsIII），3.5；砷酸钠（AsV）， 0.1；单甲基拉森酸（MMA）， 3.1；二甲基胂酸（DMA）， 42.6；砷甜菜碱（AsBe）， 61.3；砷胆碱、氧化三甲基larsin和未识别的砷（其他），5.2；总砷（total As）为141.3 μgAs/1。在日本观察到的高水平的DMA和AsBe可能部分是由于海鲜的摄入。为了弄清食入羊栖菜的风险，一名42岁的男性志愿者在3个月不吃海鲜后，从8份商业羊栖菜食品中摄入了825 μg的iAs化合物。50 h内尿中AsV、AsIII、MMA和DMA的总排泄量分别为11.2、31.8、40.9和104.0 μg。因此，长期食用羊栖菜可能会导致砷中毒。

The purpose of this study was to examine the association between current arsenic level of well water and urinary arsenic concentration to examine the effectiveness of Bangladeshi mitigation programs. A community-based cross-sectional study was conducted in the Pabna district of Bangladesh between May and July 2005. We included 174 married couples and collected their drinking water from 138 wells. Of 326 subjects, 304 cases exceeded urinary arsenic level of 40μg/1.5L/day. Of all wells, 23.1% wells had arsenic level >50 μg/L. Multiple-adjusted odds ratio of urinary arsenic level >40μg/1.5L/day were 8.90 (95% CI : 3.31-23.93) for arsenic level of well water of 11-50 μg/L and 53.07 (11.91-236.46) for that of 51.332 μg/L as compared with that of 【less than or equal】10 μg/L. These results suggest that arsenic level of well water of 11.50 μg/L that Bangladesh government regarded as safe were not safe.We performed speciation analysis of urinary arsenic for 210 Japanese male subjects without occupational exposure using HPLC-ICP-MS. The median values of urinary arsenics were as follows : sodium arsenite (AsIII),3.5 ; sodium arsenate (AsV), 0.1 ; monomethylarsonic acid (MMA), 3.1 ; dimethylarsinic acid (DMA), 42.6 ; arsenobetaine (AsBe), 61.3 ; arsenocholine, trimethylarsine oxide, and unidentified arsenics (others), 5.2 ; and total arsenic (total As), 141.3 μgAs/1. It appears that the high levels of DMA and AsBe observed in Japan may be due in part to seafood intake.To clarify the risks of Hijiki ingestion, a 42-year-old male volunteer ingested 825 μg of iAs compounds contained in eight servings of commercial Hijiki food, after refraining from eating seafood for 3 months. The total amounts of AsV, AsIII, MMA and DMA excreted in urine over 50 h were 11.2, 31.8, 40.9 and 104.0 μg, respectively. Long-term ingestion of Hijiki might thus have the potential to cause arsenic poisoning.