Environmental assessment of toxic metals from Canal on Mehran University water treatment plant, Jamshoro, Pakistan

The main aim of this study was to evaluate the heavy metals in Mehran University water treatment plant, Jamshoro District, Sindh, Pakistan. The water samples were collected throughout the year (June 2016 to May 2017) from different locations such as raw water source (Kalri Baghar feeder), Mehran University water treatment plant and water distribution network from water treatment plant to the departments of Mehran University. The water samples from different locations were coded as S1 (Kalri Baghar Feeder/intake raw water source), from Mehran University water treatment plant (S2–S4), i.e., S2 (sedimentation tank outlet), S3 (post-filtration), S4 (Mehran University storage tank) and at last from Mehran University department, i.e., S5 (institute of water resources management), respectively. The atomic absorption spectrometry technique was used to evaluate the levels of heavy metals in water samples from different locations. The ranges of mean concentrations were analyzed from different locations (S1, S2, S3, S4 and S5) in Mehran water treatment plant such as for zinc from 60.368 to 137.6 µg/L, for copper from 1.82 to 4.08 µg/L, for chromium from 1.709 to 3.448 µg/L, for arsenic from 3.08 to 4.29 µg/L, for mercury and cadmium were observed under below detection limit. The detection limit of these metals was observed at 1, 0.5, 0.2, 2, 2 and 0.05 µg/L for zinc, copper, chromium, arsenic, cadmium and mercury, respectively. The recovery of the spike analyte was observed from 95 to 103% in different locations. The observed concentrations of selected heavy metals are under World Health Organization and National Environmental Quality Standards guideline limits.