Foodborne metal(loid) contamination from coastal petrochemical industrial zone to countryside and urban zones: Spatial distribution and public health implications.

Abstract

As industrialization and urbanization intensify in coastal regions, pollution from petrochemical zones can impact the metal(loid) content in food from nearby countryside and urban zones, posing public health risks. However, systematic assessments of the impact of coastal petrochemical activities on dietary metal(loid) exposure across countryside and urban populations remain limited. This study evaluated the spatial distribution and health risks of metal(loid) pollution along a land-use gradient-including a coastal petrochemical industrial zone, countryside, and urban zones. Food samples from the coastal petrochemical industrial zone showed elevated concentrations of toxic metal(loid)s, with As ranging from 2.40 to 5506.69 μg/kg, Cd from 1.07 to 4023.70 μg/kg, and Pb from 0.12 to 510.00 μg/kg-especially in seafood and leafy vegetables. The Total Target Hazard Quotient (TTHQ) often exceeded the safety threshold (TTHQ > 1), indicating potential chronic non-carcinogenic risks. Carcinogenic Risk (CR) values for arsenic were within or only slightly above the acceptable range (1 ×10⁻⁶ to 1 ×10⁻⁴), suggesting possible long-term health threats. Locally Linear Embedding (LLE) combined with Random Forest regression suggests that coastal industrial activities are encroaching on neighboring areas and affecting the food of residents in non-industrial zones, and Zn, Se, Pb, and Mn emerge as the main drivers of the inter-zone differences and as the key metal(loid)s through which the coastal petrochemical industrial zone influences the environment.