Deep and shallow tubewell water from an arsenic-contaminated area in rural Bangladesh: risk-based status

Abstract

For all living organisms on the planet Earth, safe drinking water is essential. Throughout the world, millions of people such as those in Bangladesh utilize ground water sources like deep tubewells or shallow tubewells as sources for safe drinking water. In this study, drinking water supplies for people in rural communities are investigated in one arsenic-contaminated area, Narail Sadar, Bangladesh, for the purpose of ensuring safe potable water. Trace metals, namely arsenic, iron, manganese, cadmium, zinc and lead in the water of deep (n = 22) and shallow (n = 27) tubewells, were determined by atomic absorption spectrophotometer following APHA standard analytical methods. The examined parameters of water samples regarding the deep tubewell were found to have the following ranges: arsenic 2–145 µg/L; iron 80–6710 µg/L; manganese 8–80 µg/L; cadmium 1–8 µg/L; zinc 3–433 µg/L; and lead below the detection limit of 6 µg/L. In the shallow tubewell, the statistics were: arsenic 2–321 µg/L; iron 110–8670 µg/L; manganese 8–620 µg/L; cadmium 2–9 µg/L; zinc 3–81 µg/L; and lead below the detection limit of 6 µg/L. Drinking water quality of Narail Sadar does not satisfy the guidelines published by the World Health Organization or the government standards in Bangladesh. Deep tubewell water is comparatively less contaminated by arsenic and other trace metals than the shallow tubewell water, a finding based on the hazard quotient, carcinogenic risk and water quality index. Regular consumption of arsenic-contaminated water may accelerate chronic arsenic-related toxicity and subsequently endanger people’s health.