Variable Effectiveness of Raw Rice, Cooked Rice, and Water in Recapitulating Dietary Inorganic and Organic Arsenic Exposure in the Health Effects of Arsenic Longitudinal Study.

Cooked rice provides a more reliable indicator of dietary arsenic exposure than raw rice or water, especially when water arsenic exceeds safety limits, but neither fully explains urinary arsenic levels at low exposure.

• Why it matters: Understanding the most effective sample type for arsenic exposure monitoring is crucial for accurate risk assessment and public health interventions, particularly in regions with variable water and rice arsenic levels.
• What they did: Matched samples of raw rice, cooked rice, cooking water, and urine from 396 Bangladeshi participants were analyzed to compare arsenic levels and their relationship to urinary arsenic, focusing on inorganic arsenic and methylated metabolites.
• The result: Cooked rice best reflects dietary arsenic exposure across diverse water arsenic levels, and methylation efficiency measures based on urinary MMA and DMA remain reliable, supporting their use in epidemiological studies.