Deterministic and probabilistic health risk assessment of toxic metals in daily diets of residents in industrial regions of northern Ningxia, China

Abstract

This study was designed to investigate the toxic metals (aluminum (Al), arsenic (As), chromium (Cr), cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn)) concentrations in drinking water and different foodstuffs (cereals, meat, beans, potatoes, solanaceous fruits, vegetables, and fruits) and then estimate the potential health risks of toxic metals via consumption to the local residents in industrial regions of northern Ningxia, China. Inductively coupled plasma atomic emission spectrometry was performed to detect toxic metal concentrations. According to the results, the concentrations of As, Cr, Ni, Pb, and Zn in fruit samples exceeded the standard limits. Pb was the most common toxic metal detected in drinking water, cereals, beans, potatoes, solanaceous fruits, vegetables, and fruits.The results of deterministic assessment of health risks showed that the total noncarcinogenic health risk value of dietary intake of toxic metals by the local population was 5.6106, indicating that toxic metals pose a high noncarcinogenic risk to residents under the current daily diet exposure. The order of noncarcinogenic health risk values of various foods analyzed was as follows: HIcereals (1.2104) > HIsolanaceous fruits (0.9134) > HIvegetables (0.8726) > HIfruits (0.8170) > HImeat (0.7269) > HIdrinking water (0.6139) > HIbeans (0.2991) > HIpotatoes (0.1573). The total carcinogenic health risk from exposure to toxic metals through dietary intake was 9.98×10− 4, indicating that the total cancer risk value of residents is beyond the acceptable range under the current daily dietary exposure, and implies a high risk of cancer. The order of carcinogenic health risk (R) was Rdrinking water (2.34×10− 4) > Rmeat (2.11×10− 4) > Rsolanaceous fruits (1.89×10− 4) > Rfruits (1.88×10− 4) > Rcereals (1.36×10− 4) > Rpotatoes (2.44×10− 5) > Rvegetables (1.51×10− 5) > Rbeans (0.00). Probabilistic assessment results showed that 98.83% of the population would suffer severe noncarcinogenic risk and 87.02% would suffer unacceptable carcinogenic risk. Sensitivity analysis showed that drinking water, local cereals, vegetables, and fruits were the major contributors to health risks. Our results indicated that daily dietary exposure of residents in industrial regions of northern Ningxia posed a serious threat to human health, and appropriate strategies should be adopted to prevent toxic metal contamination.