Dietary intake and urinary excretion of methylated arsenicals of Japanese adults consuming marine foods and rice

ABSTRACT

Dietary intake and urinary excretion of monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine (AsB) were measured in 150 adult Japanese subjects. Duplicate diet (DD) samples and first void of urine on the next morning of DD sampling day were collected and analysed for arsenic species with liquid chromatography-ICP mass spectrometry. Median (min-max) intakes of MMA, DMA and AsB were <2.3 (<2.3-<2.3), 4.57 (<2.3–24.3), and 13.6 (<2.4–231) μg As/day, respectively, and median urinary concentrations were 1.90 (<0.37–26.), 21.9 (<0.27–141) and 19.6 (<0.37–1063) ng As/mg creatinine, respectively. Interrelationships between intake levels and urinary concentrations were mostly significant with positive coefficients indicating mutual association due to co-exposure, metabolism and/or dietary habit. Urinary concentrations and intake levels of AsB were also positively correlated confirming the applicability of urine analysis as biomarker of exposure. The present descriptive results provide with essential piece of information in assessing health risk of methylated arsenicals for population who consume marine products and rice.

KEYWORDS:

• Monomethylarsonic acid
• dimethylarsinic acid
• arsenobetaine
• daily intake
• urinary excretion

Acknowledgments

The authors thank all the participants of this study who donated urine and duplicate diet. Technical assistance of Ms. Y. Amagai, Y. Nakamura, R. Takaku and K. Mashimo is deeply appreciated.

Additional information

Funding

This study was partly supported by a grant from the Food Safety Commission, Cabinet Office, Government of Japan (Research Program for Risk Assessment Study on Food Safety, No. 1704).