Evaluation of radon concentration and heavy metals in drinking water and their health implications to the population of Quetta, Balochistan, Pakistan

Determination and health risk assessment of trace elements in the tap water of two Sub-Cities of Addis Ababa, Ethiopia

“…Comparably, the average Cr content in the other study reported values was 18 times ( Egbueri and Unigwe, 2020 ) and 50 times ( Nawab et al., 2018 ) far less than the Akaki-Kality Sub-City drinking water. Moreover, the average concentrations of Cr in the Akaki-Kality Sub-City was found to be 5 times ( Hu et al., 2019 ), 3 times ( Mohammadi et al., 2019 ), 3 times ( Fallahzadeh et al., 2017 ; Gupta et al., 2017 ) and 2 times ( Ahmad et al., 2020 ) less than the reported data elsewhere.…”

“…While the average concentrations of Ni in the Akaki-Kality Sub-City were found to be 0.92 ± 0.13 μg/L. The recorded concentration of Ni content in the Akaki-Kality Sub-City was approximately 23 times ( Khalid et al., 2020 ), 5 times ( Ahmad et al., 2020 ), and 2 times ( Alidadi et al., 2019 ; Muhammad et al., 2011 ) greater than the current value. On the contrary, the results of other studies showed values were 24 times ( Egbueri and Unigwe, 2020 ) and 15 times ( Mohammadi et al., 2019 ) lower level of Ni than the current value.…”

“…(2017) , Iran 3.12 ± 1.10–1459.25 ± 21.48 8.07 ± 1.06–21.43 ± 4.01 10.51 ± 1.19–428.61 ± 13.44 1.00 ± 0.04–47.19 ± 3.95 ND - 7.71 ± 2.05 - ND - 5.91 ± 2.14 5.88 ± 4.94 (1.22–582.00) GW Egbueri and Unigwe (2020) , Nigeria 0.35 ± 0.58 (0.04–1.74) 0.55 ± 0.78 (0.00–3.14) 0.72 ± 0.48 (0.05–1.73) 0.01 ± 0.03 (0.00–0.13) 0.04 ± 0.16 (0.00–0.73) - 0.001 ± 0.01 (0.00–0.02) 32.10 ± 85.40 (0.00–320.00) GW Mazhar and Ahmad (2020) , India - 11.00–305.00 750.00–2245.00 11.00–1360.00 247.00–1246.00 - - 0.01–1.64 GW Mohammadi et al. (2019) , Iran - 0.10–39.31 7.41–104.77 - 0.06–19.45 - 0.35 -8.27 5.08 (0.39–10.76) GW Ahmad et al. (2020) , Pakistan - - - - 5.06 ± 1.19 1.80 ± 0.64 5.58 ± 1.23 3.21 ± 0.75 GW WHO 300 2000 3000 400 70 10 10 50 USEPA 300 1300 500 500 20 10 15 100 GW = Groundwater, SW = surface water, S&G = surface and groundwater.…”

“…They are classified as toxicants and human carcinogens and induce multiple organ damage even at low concentrations ( Ahmad et al., 2020 ; Nthunya et al., 2017 ; Tyler and Allan, 2014 ; WHO, 2008 ). Pb and As contents in the two Sub-Cities were also lower than the reported values ( Huq et al., 2019 ; Mirzabeygi et al., 2017 ; Nawab et al., 2018 ; Rasool et al., 2016 ; Sadeghi et al., 2018 ), but similar values were reported from Pakistan ( Ahmad et al., 2020 ). Even if these metals were found in small amounts in both selected research areas, the long-term exposures of these toxic metals may cause detrimental health effects on humans.…”

“…Several studies were performed previously in different countries assessing the heavy metal contamination in different environmental samples such as water, sediment, soil, and foodstuff ( Ahmad et al., 2020 ; Alidadi et al., 2019 ; Barbieri et al., 2019 ; Egbueri and Unigwe, 2020 ; Jehan et al., 2020 ; Khalid et al., 2020 ; Mazhar and Ahmad, 2020 ; Rasool et al., 2016 ; Sarvestani and Aghasi, 2019 ). However, there is no assessment in Addis Ababa, the capital city of Ethiopia, related to the municipal water supplies.…”