Hazardous concentrations of selenium in soil and groundwater in North-West India

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• 作者：Mini Bajaj^a ; ^{mini.bajaj@kit.edu"" rel=""nofollow} ; Elisabeth Eiche^b ; ^{elisabeth.eiche@kit.edu"" rel=""nofollow} ; Thomas Neumann^b ; ^{neumann@kit.edu"" rel=""nofollow} ; Josef Winter^a ; ^{josef.winter@kit.edu"" rel=""nofollow} ; Claudia Gallert^a ; ^{claudia.gallert@kit.edu"" rel=""nofollow}
• 关键词：Selenium ; Agricultural soil ; Irrigation water ; Elemental analyses ; Mineralogical analyses ; Selenate reduction
• 刊名：Journal of Hazardous Materials
• 出版年：2011
• 出版时间：30 May 2011
• 年：2011
• 卷：189
• 期：3
• 页码：640-646
• 全文大小：643 K

文摘

Soil and groundwater samples were collected for bulk elemental analyses in particular for selenium (Se) concentrations from six agricultural sites located in states of Punjab and Haryana in North-West India. Toxic concentrations of Se (45–341 μg L⁻¹) were present in groundwater (76 m deep) of Jainpur and Barwa villages in Punjab. Selenium enrichments were also found in top soil layers (0–15 cm) of Jainpur (2.3–11.6 mg kg⁻¹) and Barwa (3.1 mg kg⁻¹). Mineralogical analyses confirmed silicates and phyllosilicates as main components of these soils, also reflected by the high content of SiO₂ (40–62 wt. % ), Al₂O₃ (9–21 wt. % ) and K₂O (2.2–3.2 wt. % ). Prevailing intensive irrigation practices in Punjab with Se enriched groundwater may be the cause of Se accumulation in soils. Sequential extraction revealed >50 % Se bioavailability in Jainpur soils. Appearance of selenite was observed in some of the batch assays with soil slurries under reducing conditions. Although safe Se concentrations were found in Hisar, Haryana, yet high levels of As, Mo and U present in groundwater indicated its unsuitability for drinking purposes. Detailed biogeochemical studies of Se in sediments or groundwater of Punjab are not available so far; intensive investigations should be started for better understanding of the problem of Se toxicity.