Abstract
Louhajang River, Bangladesh, which crosses Tangail as a densely industrialized and urbanized city, supplies water for different purposes. This study reports the levels of pH, electrical conductivity (EC), and some toxic heavy metals in 40 water samples collected during the summer and winter seasons from Louhajang River. The winter season reported higher levels of the examined parameters than the summer season with significant variation (p < 0.05) for all parameters, with the exception of Cd. The metal contents were assessed against local and international standards for drinking, irrigation, and aquatic life purposes where different trends were observed. The heavy metal evaluation index and the ecological risk index reported low to moderate risks. The spatial distribution of metal contents assigned hot spots in some sites along the riverbed. The health risk assessment for three population categories, i.e., adult male, adult female, and children, was examined. Cr and Cd recorded hazard index > 1 in all cases, indicating possible non-cancer risk. The total carcinogenic risk values during both seasons were > 1.0 x 10(-6), indicating possible cancer risk. The adopted collection of different approaches (comparison against standard levels of toxicants, statistical analysis, spatial distribution, and health risk assessment) successfully demonstrates a whole picture of the environmental status of Louhajang River, Bangladesh.