title: Arsenic and other heavy metals in soils from an arsenic-affected area of West Bengal, India.
abstract: Domkal is one of the 19, out of 26 blocks in Murshidabad district where groundwater contains arsenic above 0.05 mg/l. Many millions of cubic meters of groundwater along with arsenic and other heavy metals are coming out from both the hand tubewells, used by the villagers for their daily needs and shallow big diameter tubewells, installed for agricultural irrigation and depositing on soil throughout the year. So there is a possibility of soil contamination which can moreover affect the food chain, cultivated in this area. A somewhat detailed study was carried out, in both micro- and macrolevel, to get an idea about the magnitude of soil contamination in this area. The mean concentrations (mg/kg) of As (5.31), Fe (6740), Cu (18.3), Pb (10.4), Ni (18.8), Mn (342), Zn (44.3), Se (0.53), Mg (534), V (44.6), Cr (33.1), Cd (0.37), Sb (0.29) and Hg (0.54) in fallow land soils are within the normal range. The mean As (10.7), Fe (7860) and Mg (733) concentrations (mg/kg) are only in higher side whereas Hg (0.17 mg/kg) is in lower side in agricultural land soils, compared to the fallow land soils. Arsenic concentrations (11.5 and 28.0 mg/kg respectively) are high in those agricultural land soils where irrigated groundwater contains high arsenic (0.082 and 0.17 mg/l respectively). The total arsenic withdrawn and mean arsenic deposition per land by the 19 shallow tubewells per year are 43.9 kg (mean: 2.31 kg, range: 0.53-5.88 kg) and 8.04 kg ha(-1) (range: 1.66-16.8 kg ha(-1)) respectively. For the macrolevel study, soil arsenic concentration decreases with increase of distance from the source and higher the water arsenic concentration, higher the soil arsenic at any distance. A proper watershed management is urgently required to save the contamination.
authors.affiliation: Division of Environmental Chemistry and Exposure Assessment, National Institute of Health Sciences, Tokyo, Japan. tarit@nihs.go.jp
authors.forename: Tarit
authors.initials: T
authors.lastname: Roychowdhury
authors.forename: Tadashi
authors.initials: T
authors.lastname: Uchino
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tokunaga
authors.forename: Masanori
authors.initials: M
authors.lastname: Ando
mesh_terms: D000383:Agriculture / Q000379:methods; D001151:Arsenic / Q000032:analysis*; D020387:Food Chain; D005843:Geography; D006801:Humans; D007194:India; D013058:Mass Spectrometry / Q000379:methods; D019216:Metals, Heavy / Q000032:analysis*; D008872:Microwaves; D012015:Reference Standards; D012044:Regression Analysis; D012680:Sensitivity and Specificity; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D001151:Arsenic