Superfund Research Program
The Resilience of Low-Arsenic Aquifers and their Role in Reducing Human Exposure
Final Progress Reports
The sixth follow-up of the Health Effects of Arsenic Longitudinal Study (HEALS) cohort completed in 2018 and jointly orchestrated by The Resilience of Low-Arsenic Aquifers and their Role in Reducing Human Exposure Project with the Health Effects of Arsenic Longitudinal Study Project of the Columbia University SRP shows a dramatic decline in exposure since recruitment in 2000–2001 attributable to the sharing of low-arsenic (As) shallow wells, the private installation of intermediate low-As wells, but much less so to the installation of ostensibly public deep wells by the government. The findings are consistent with a comparative analysis of the impact of private and public measures to reduce As exposure based on data beyond the HEALS area showing that private measures have been much more cost-effective but require a renewed blanket testing throughout the country (Krupoff 2020). The research team has completed its study of the impact of distal Dhaka pumping on groundwater As concentrations in pre-Holocene aquifers tapped by thousands of new private wells. Growing hydrological and geochemical evidence that low-As aquifers in the 40-90 m depth range are particularly vulnerable to pumping-induced contamination with As has resulted in two recent publications first-authored by former trainees (Mihajlov 2020; Mozumder 2020). A new field procedure to screen paddy soil for accumulated arsenic in relation to rice yield was also published (Huhmann 2021). Data from this project and two data sets from the US were used to recommend sampling intervals for private wells in relation to their arsenic content (Mailloux 2020).