Dietary Exposure to Chromium and Barium in Shiraz, Iran: A Total Diet Study with Probabilistic Health Risk Assessment

Dietary exposure to potentially toxic metals remains a significant public health concern. This total diet study quantified chromium (Cr) and barium (Ba) in foods commonly consumed in Shiraz, Iran, and evaluated the associated health risks. A total of 108 food items representing 20 food groups yielded 545 samples (540 food and 5 drinking water samples), which were analyzed by ICP-OES. Dietary intake was estimated using local consumption data, and health risks were assessed using hazard quotient (HQ), hazard index (HI), and total cancer risk (TCR) through Monte Carlo simulation (10,000 iterations). Mean Cr and Ba concentrations were 4.07 ± 3.70 and 0.998 ± 1.717 mg/kg, respectively. Chromium concentrations ranged from 0.68 to 10.61 mg/kg, with the highest levels in fish and fruits, while Ba concentrations ranged from 0.006 to 2.93 mg/kg and were highest in legumes and cereals. Fruits contributed the largest share of dietary Cr and Ba intake. Estimated daily intakes for a 72-kg adult were 0.12 and 0.022 mg/kg body weight/day for Cr and Ba, respectively, corresponding to 41.7% and 11.5% of the tolerable daily intakes established by EFSA and WHO. All HQ and HI values were below 1, indicating negligible non-carcinogenic risk, and screening TCR values for total Cr were within the acceptable range (10⁻⁶-10⁻⁴). Although Cr concentrations in some foods exceeded typical background levels, overall dietary exposure remained below health-based guidance values. These findings provide baseline data for dietary exposure assessment and support continued surveillance of metal contamination in the food supply.