Assessment of arsenic contamination in soils and waters in some areas of Bangladesh

The soil samples and tubewell waters were collected from 25 locations representing five thanas of four districts of Bangladesh. The soils were collected from three depths viz. 0-15, 15-30 and 30-45 cm and tubewell waters were collected from same locations. The arsenic content of soils and waters were detected by Molybdenum blue method. The arsenic content in soils ranged from 1.27-56.68, 3.18-54.77, 1.27-50.95, 1.27-39.48 and 3.18-35.66 ppm in Chapainawabganj Sadar, Kustia Sadar, Bera, Ishurdi and Sarishabari thanas, respectively. Out of a total of 25 samples arsenic was detectable for 18 samples at 0-15 cm, 17 samples at 15-30 cm and 15 samples at 30-45 cm depth. One sample at 0-15 cm, 7 samples at 15-30 cm and 4 samples at 30-45 cm depth were found to be slightly contaminated. In tubewell water the arsenic content measured from Chapainawabganj Sadar, Kustia Sadar, Bera, Ishurdi and Sarishabari thanas were ranged 0.010-0.056, 0.010-0.071, 0.010-0.056, 0.010-0.056 and 0.025-0.071 ppm, respectively. Out of 25 water samples 17 contained variable amounts of arsenic where 6 sampling sites contained arsenic levels above 0.05 ppm, and these sites are Rajarampur of Chapainawabganj Sadar thana, Jordaha of Bera thana, Courtpara of Kustia Sadar thana, Nalgari of Ishurdi thana and Ijarapara of Sarisabari thana. Arsenic contained in soils was positively correlated with arsenic content in waters.