Physicochemical quality, microbial load and health risk assessment of groundwater in view of the sustainable development goals 3, 6, and 11 in Osogbo, Nigeria

Abstract

Water is abundantly available, but that of good quality for good health and well-being is not accessible thereby making cities and communities to be doubted for sustainability. Ascertaining water of good quality requires more than comparing the laboratory results with regulatory standards; exploring the multifaceted approach to check the quality of water is highly imperative and mundane to achieving the related SDGs 3, 6, and 11 to this study. The Osun Water Corporation Laboratory analysed physicochemical parameters, heavy/ toxic metals, and microbial loads of ten households’ water samples across Osogbo and environs, Osun State, Nigeria. The obtained data were descriptively compared with four drinking water standards, recent works (2018-2024), and further subjected to health risk assessments (CDI, CDI_ing, CDI_derm, HQ, HI, and PLCR) using SPSS v23. The results indicated that the consumers were not free from microbial loads (total plate count, total coliform, and Escherichia coli in 100 % locations), cyanide (in 60 % locations), K (in 90 % locations), Cr (in 60 % locations), Cd (in 100 % locations), Mo (in 80 % locations), N-nitrate, and Free CO₂ contamination as their levels were higher than the limits of WHO, UNICEF (2014), and NIS 554 (2015) while HCO₃^- was higher that the WHO (2008) limit. The average CDI_ing values ranged from 3.77E-2 at location C to 8.54E-3 at location H for children and from 1.32E-1 at location C to 3.00E-2 at location H for adults. The average CDI_derm values ranged from 2.48E-4 at location C to 5.64E-5 at location H for children and from 4.61E-4 at location C to 1.05E-2 at location H for adults. The HQ_ing of Cd, Cr, and Cu were > 1, while the HQ_derm of Cd was > 1, thereby indicating a low non-carcinogenic risk. The adults’ HI_ing was higher than that of the children except at locations DEC. The PLCR_ing for adults > PLCR_ing for children > PLCR_derm for adults > PLCR_derm for children. The study concluded that the health implications of the limit-exceeded parameters determined noncompliance with SDGs 3, 6, and 11. The children were more prone to ingestion and dermally-contact side effects than the adults. The HQ_ing is generally > HQ_derm. There is a need for a joint effort to make potable water available for the residents of Osogbo and its environs.