Study of Contaminants in Iranian Drinking Water and their Health Outcomes: A Review

Contamination of ground and surface water resources with Nitrate (NO3), Fluoride (F), Trihalomethanes (THMs), radon, and heavy metals is the most important global concern due to its possible health risks to people. This study reviews the drinking water contaminants and their health outcomes examined in Iran. A review search was conducted using Scopus, Web of Knowledge, PubMed, and Embase databases for associated released articles from 2014 to 2023, resulting in 86 articles relevant to the objective of this study. According to the results of this review, different emerging contaminants were found in potable water, including THMs, NO3, F, radon and heavy elements (i.e., As,  Pb, Ni, Cd, Zn, Cu, and Cr). Health outcomes of exposure to radon, F, NO3, THMs, and heavy metals in potable water have been expressed in various epidemiological research studies. More than 65% of the studies reported hazard index (HI) or hazard quotient (HQ) of heavy elements to be greater than one in potable water in Iran for infants, children, teenagers, and adults. Children and infants are at higher health risk than adults in these areas. The level of Arsenic, Cadmium, Lead, Nickel, Zinc, and Chromium, in 26, 26, 17.39, 13.04, 8.69, and 4.3% of the papers was more than the allowable limits, respectively. Various groups of emerging pollutants have been found in potable water in Iran, while epidemiological research studies on their health outcomes are still insufficient.