title: Efficacy of arsenic filtration by Kanchan arsenic filter in Nepal.
abstract: Groundwater arsenic contamination has caused a significant public health burden in lowland regions of Nepal. For arsenic mitigation purposes, the Kanchan Arsenic Filter (KAF) was developed and validated for use in 2003 after pilot studies showed its effectiveness in removing arsenic. However, its efficacy in field conditions operating for a long period has been scarcely observed. In this study, we observe the efficacy of KAFs running over 6 months in highly arsenic-affected households in Nawalparasi district. We assessed pair-wise arsenic concentrations of 62 randomly selected household tubewells before filtration and after filtration via KAFs. Of 62 tubewells, 41 had influent arsenic concentration exceeding the Nepal drinking water quality standard value (50 μg/L). Of the 41 tubewells having unsafe arsenic levels, KAFs reduced arsenic concentration to the safe level for only 22 tubewells, an efficacy of 54%. In conclusion, we did not find significantly high efficacy of KAFs in reducing unsafe influent arsenic level to the safe level under the in situ field conditions.
authors.affiliation: Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu, Nepal E-mail: maden.narendra@gmail.com.
authors.forename: Anjana
authors.initials: A
authors.lastname: Singh
authors.affiliation: Filters for Families, Dhobighat, Lalitpur, Nepal and Department of Geology, University of Texas at Dallas, Richardson, Texas, USA.
authors.forename: Linda S
authors.initials: LS
authors.lastname: Smith
authors.affiliation: Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu, Nepal E-mail: maden.narendra@gmail.com.
authors.forename: Shreekrishna
authors.initials: S
authors.lastname: Shrestha
authors.affiliation: Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu, Nepal E-mail: maden.narendra@gmail.com.
authors.forename: Narendra
authors.initials: N
authors.lastname: Maden
mesh_terms: D001151:Arsenic / Q000737:chemistry*; D005374:Filtration / Q000592:standards*; D060587:Groundwater / Q000032:analysis*; D009390:Nepal; D013054:Spectrophotometry, Atomic; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D014874:Water Pollutants, Chemical; D001151:Arsenic