Groundwater arsenic contamination in Brahmaputra river basin: a water quality assessment in Golaghat (Assam), India

Abstract

Distribution of arsenic (As) and its compound and related toxicology are serious concerns nowadays. Millions of individuals worldwide are suffering from arsenic toxic effect due to drinking of As-contaminated groundwater. The Bengal delta plain, which is formed by the Ganga-Padma-Meghna-Brahmaputra river basin, covering several districts of West Bengal, India, and Bangladesh is considered as the worst As-affected alluvial basin. The present study was carried out to examine As contamination in the state of Assam, an adjoining region of the West Bengal and Bangladesh borders. Two hundred twenty-two groundwater samples were collected from shallow and deep tubewells of six blocks of Golaghat district (Assam). Along with total As, examination of concentration levels of other key parameters, viz., Fe, Mn, Ca, Na, K, and Mg with pH, total hardness, and SO[Formula: see text], was also carried out. In respect to the permissible limit formulated by the World Health Organization (WHO; As 0.01 ppm, Fe 1.0 ppm, and Mn 0.3 ppm for potable water), the present study showed that out of the 222 groundwater samples, 67%, 76.4%, and 28.5% were found contaminated with higher metal contents (for total As, Fe, and Mn, respectively). The most badly affected area was the Gamariguri block, where 100% of the samples had As and Fe concentrations above the WHO drinking water guideline values. In this block, the highest As and Fe concentrations were recorded 0.128 and 5.9 ppm, respectively. Tubewell water of depth 180±10 ft found to be more contaminated by As and Fe with 78% and 83% of the samples were tainted with higher concentration of such toxic metals, respectively. A strong significant correlation was observed between As and Fe (0.697 at p<0.01), suggesting a possible reductive dissolution of As-Fe-bearing minerals for the mobilization of As in the groundwater of the region.

Assessment of Ground Water Quality of Greater Guwahati With Reference To Iron and Fluoride

“…It is seen, in almost all the investigated locations, water collected directly from the source has high concentration of iron. Similar results were observed in case of iron concentration in ground water samples at Brahmaputra river basin in Golaghat (Assam), India [14]. Table III.…”

Preliminary Assessment of Arsenic Distribution in Brahmaputra River Basin of India Based on Examination of 56,180 Public Groundwater Wells

“…In a study conducted in 2010 (Mahanta et al 2008 ), concentrations beyond 50 μg/L have been confi rmed in 72 blocks out of 214 blocks in 22 districts of Assam. A study by Chetia et al ( 2011 ) in the Golaghat district reported As concentration ranging between 1 and 128 μg/L in six blocks of the district. These studies so far have remained spatially limited and a comprehensive picture is yet to emerge.…”

Status of Soil Pollution in India

“…Analysis of 140150 water samples from tube wells in all 19 districts of West Bengal for arsenic indicated that 48.1% samples had As >10 μg L À1 (WHO guideline value), 23.8% had >50 μg L À1 (Bureau of Indian Standard) and 3.3% had >300 μg L À1 (concentration predicting overt arsenical skin lesions) (Chakraborti et al 2009). Arsenic contamination of groundwater, soil and food had also been reported from other regions of India such as Uttar Pradesh, Jharkhand, Bihar, Madhya Pradesh, Chhattisgarh, Assam, Manipur, Tripura, Arunachal Pradesh, Punjab and Andhra Pradesh (Chakraborti et al 1999(Chakraborti et al , 2003Chetia et al 2011;Govil et al 2001;Mukherjee et al 2006;Rao et al 2001;Sharma et al 2016). In a study in the state of Punjab, the concentration of As in 200 groundwater and surface soil samples were analyzed .…”