Global patterns and exposure assessment of cereal arsenic contamination

Arsenic contamination in cereal crops represents a critical global food safety concern requiring systematic assessment. We conducted a comprehensive meta-analysis of 2,895 arsenic data records from 736 publications (1979-2023) covering rice, wheat, and corn globally. Spatial distribution analysis using ArcGIS and advanced statistical modeling revealed a clear contamination hierarchy: rice (0.1 mg/kg) > wheat (0.05 mg/kg) > corn (0.03 mg/kg). Geographic patterns showed concentration of high-contamination zones in Asia, particularly China and Central Asian republics. Temporal analysis demonstrated stable rice and wheat levels over 35 years, while corn showed 62.5% improvement since 1985. Health risk assessment using updated JECFA reference points (3 μg·kg⁻¹·d⁻¹) identified critical exposure patterns. Bangladesh represents the extreme-risk epicenter, where adults consuming wheat/corn and children consuming corn exhibited Margin of Exposure (MOE) values below the safety threshold (MOE < 1). This indicates their estimated daily intake (EDI) of inorganic arsenic exceeded the benchmark dose lower confidence limit (BMDL0.5), posing severe health threats. Climate change may increase rice arsenic by 25%, which could further exacerbate these risks, particularly in high-exposure regions like Bangladesh. The Asia-Pacific region bears the greatest burden, with Bangladesh alone illustrating a critical public health crisis affecting millions. Immediate priorities must include targeted interventions in high-risk regions, strengthening monitoring systems, implementing pediatric-specific standards, and integrating climate impacts into contamination management frameworks.