Evaluation of water from Lake Coatetelco in central-south Mexico and surrounding groundwater wells for drinking and irrigation, and possible health risk

Abstract

With an increasing reduction of hydrological resources across Mexico and their growing contamination due to global warming and anthropogenic activities, this study evaluated water from the perennial Lake Coatetelco (Ca–Mg–HCO3) in tropical central-southern Mexico and groundwater (Ca–Mg–HCO3 and Na–HCO3–Cl) from the surrounding wells for drinking as well as irrigation qualities. Comparison with the WHO guidelines, and the estimated water quality indices (DWQI and IWQI) grouped almost all the samples collected after the warm season rainfall in excellent and good categories (DWQI < 100) for drinking, even though fluoride remained > 1.5 mg/L in 50% samples. Except for one groundwater sample, all showed > 25% permeability (classes I and II) in Donnen classification indicating their suitability for irrigation. USSL and Wilcox classifications, however, catalogued some in the high-salinity hazard group and some as doubtful for irrigating regular plants. Samples from about 53% wells are also in high and severe restriction irrigation categories of IWQI. Total Hazard Quotient Index (THQI) of non-carcinogenic risk results (HQfluoride>1) shows that at least one lake water sample and 47% of groundwater might expose both adult and child population to possible risk of dental and skeletal fluorosis. This baseline information about water quality might be useful for both the short- and long-term monitoring and evaluation in this region.