Abstract
Unrequested health effects of a long-term intake of arsenic contaminated ground water have been known since a long time in Nepal and other countries in South-East Asia. Nowadays, so called Kanchan filters are installed in the lowland of Nepal but their removal efficiency has hardly ever been evaluated. This mini review reports about the constraints determined to influence the removal efficiency: Besides geological (mineralogy of the sediments), geochemical (pH, redox conditions, temperature, and solution composition) and handling (e.g. drying of the nail bed) issues, the maintenance of the filters by the involved residents is a major and underestimated concern.

Keywords
Arsenic, iron, decoupling, clay minerals, Kanchan filter, removal

Cite this paper
BARBARA MUELLER, Kanchan arsenic filters in Nepal: Constraints concerning removal efficiency, SCIREA Journal of Environment. Vol. 6 , No. 2 , 2022 , pp. 15 - 19 . https://doi.org/10.54647/environmental61284

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