Persistent exposure to arsenic via drinking water in rural Bangladesh despite major mitigation efforts

Objectives: Elevated arsenic levels in tube-well water in Bangladesh have prompted extensive mitigation projects. We evaluated the effectiveness of longterm mitigation efforts by longitudinally measuring arsenic exposure in pregnant women and their children, the most susceptible population groups. Methods: The study was nested in a population-based nutrition intervention in Matlab, Bangladesh. Mother-child pairs (n=1951) were followed from 2001 to 2003, beginning in early gestation and continuing to 5 years postpartum. We measured arsenic concentrations in urine (U-As) of the 5-year-old children by using high-performance liquid chromatography online with hydride generation and inductively coupled plasma mass spectrometry and compared them with earlier childhood U-As and maternal U-As during pregnancy. Results: Children had elevated U-As at 5 years old (median=51 lg/L, 5th-95th percentiles=16-355 lg/L), and U-As distribution was similar to that observed in the mothers during gestation. Children's U-As at 5 years old significantly correlated with their U-As at 1.5 years old and to maternal U-As during early and late gestation. Conclusions: Despite major mitigation efforts, arsenic exposure remains highly elevated in rural Bangladesh. Further mitigation strategies are required and must be rigorously evaluated for long-term efficacy.