Trace and toxic metal contamination in raw milk from Fayoum Governorate, Egypt and associated dietary health risks

This study aimed to determine the concentrations of selected trace and toxic metals in raw milk from dairy collection centers in Fayoum Governorate, Egypt, and to assess the associated dietary exposure and potential long-term health risks for children, adults, and the elderly. Raw milk samples were analyzed for Cu, Zn, Cr, Cd, and Pb, revealing pronounced spatial variability across sampling locations. Zn (3.59–10.30 mg/kg) and Pb (0–3.33 mg/kg) were detected at the highest concentrations, while Cd and Cr ranged from 0.37 to 0.60 mg/kg and 0.20–0.38 mg/kg, respectively. Pb concentrations exceeded international guideline limits in several samples, and contamination factor analysis classified Pb contamination as “considerable” to “very high” at sites S1, S2, S7, and S8, suggesting environmental or feed-related sources. Estimated Daily Intake (EDI) values were consistently higher in children than in adults and the elderly, particularly for Zn (0.087 mg/kg/day) and Pb (0.02 mg/kg/day). Non-carcinogenic risk assessment indicated that the Hazard Index (HI) exceeded the acceptable threshold (HI ≥ 1) for all population groups, with Cd and Pb accounting for the largest contributions to overall risk. Children represented the most vulnerable group, with HI values reaching 13.45–19.71. Carcinogenic risk estimates (ILCR) for Cr, Cd, and Pb ranged from 3.3 × 10 - ² to 5.1 × 10 - ² for children and from 7.2 × 10 - ³ to 1.4 × 10 - ² for adults and the elderly, exceeding the commonly accepted lifetime cancer risk range (10 − 6 –10 − 4 ). The results highlight potential food safety concerns associated with chronic consumption of raw milk in the study area and emphasize the importance of routine monitoring, improved feed management, and targeted regulatory measures to reduce dietary exposure to toxic metals.