OCCURRENCE OF TRIHALOMETHANES AND MULTIPLE PATHWAY HEALTH RISK EVALUATION IN DRINKING WATER IN MOROCCO

The objective of this study was to determine the concentrations of trihalomethane species in Morocco's drinking water and to assess their carcinogenic risk and non-cancer hazard index for human health via oral ingestion, dermal absorption, and inhalation.Two water sources were studied, surface water and groundwater.Sampling sites were selected along the water source to the consumer tap, via the treatment plant and the drinking water storage reservoir.Surface water has a higher trihalomethane formation potential than groundwater.Trihalomethane-total concentrations were 0 g/L (Raw water), 24.11 g/L (Filtered water), 24.82 g/L (Disinfected water), 29.98 g/L (Reservoir), 31.69 g/L (Tap water).The average percentage contribution of each THM species chloroform, bromodichloromethane, dibromochloromethane, and bromoform were 42%, 34%, 24%, 0%, respectively.The found concentrations were well below the maximum allowable value in WHO guideline.The lifetime risk of non-cancer diseases studied was lower than the (USEPA) guideline of 1.The lifetime cancer risk linked to trihalomethanes in drinking water sourced from surface supplies exceeded the 'negligible risk' threshold established by USEPA.According to the cancer risk study, inhalation presented the highest risk (90%), with chloroform having a significant impact.Furthermore, both the oral and dermal routes of exposure to bromodichloromethane and dibromochloromethane present an increased cancer risk.