Farzan et al. 2021 — Urinary arsenic in a Hispanic pregnancy cohort in Los Angeles
This study examined urinary arsenic species (total As, inorganic As, MMA, DMA) in 241 low-income predominantly Hispanic pregnant women enrolled in the MADRES (Maternal And Developmental Risks from Environmental and Social stressors) cohort in Los Angeles, California. Total urinary arsenic ranged widely from 0.8 to 506.2 µg/L, with a mean of 9.0 µg/L. Demographic predictors of higher urinary arsenic included rice consumption and seafood consumption, with rice being a particularly important dietary predictor in this Hispanic cohort where rice is a dietary staple. The study highlights the food consumption-based arsenic exposure pathway as a significant contributor to inorganic arsenic body burden in a vulnerable population (pregnant women) and a minority group with distinctive dietary patterns. The iAs to DMA ratio reflects individual variation in arsenic methylation capacity.
Key numbers
n=241 pregnant women (MADRES cohort, Los Angeles). Urinary total As: range 0.8-506.2 µg/L, mean 9.0 µg/L. Species measured: total As, iAs (inorganic), MMA, DMA. Key dietary predictors: rice consumption and seafood consumption. Method: urinary speciation analysis (ICP-MS with HPLC). Jurisdiction: US (California). Publication: J Expo Sci Environ Epidemiol 2021 Feb;31(1):94-107.
Methods (brief)
Cross-sectional urinary arsenic speciation in pregnant women at enrollment. Urine samples collected at first prenatal visit. Speciation by HPLC-ICP-MS for total As, iAs, MMA, DMA. Dietary assessment for rice and seafood consumption. Limitation: single urine sample per participant; spot urine subject to dilution (creatinine-adjusted values also reported). Cross-sectional design at one time point in pregnancy.
Implications
Certification: Urinary As data from a high-rice-consuming minority pregnancy cohort; rice is a confirmed dietary predictor of inorganic arsenic body burden in this population. Courses: Documents rice as a significant iAs exposure pathway beyond the infant rice cereal category; relevant to prenatal nutrition counseling. App: Rice consumption frequency and type (white vs. brown) are key drivers of iAs exposure in high-rice-consuming populations; seafood adds to tAs burden.