INTAKE OF INORGANIC ARSENIC IN THE NORTH-AMERICAN DIET

Dietary intake of inorganic arsenic, previously assumed to be an insig nificant source of arsenic exposure in humans, was estimated for Canad ian and United States populations. Input data included arsenic content s of various food groups, a limited historical database from the Ontar io Ministry of the Environment measuring the percent inorganic arsenic in food groups, and food consumption data. Estimated daily dietary in take of inorganic arsenic ranges from 8.3 to 14 mu g/day in the United States and from 4.8 to 12.7 mu g/day in Canada for various age groups . These data suggest that between 21% to 40% of total dietary arsenic occurs in inorganic forms. Uncertainties regarding total arsenic in da iry products in the data set applied here may account for observed dif ferences between United States and Canadian estimates. While estimates provided here are preliminary because of limitations in data on the p roportion of inorganic arsenic in foods, this analysis suggests that d ietary intake of inorganic arsenic is higher than is currently assumed . Additional research is needed to more fully characterize inorganic a rsenic concentrations in foods. Future study is also needed on the var iability of total and inorganic arsenic in foods and the bioavailabili ty of dietary inorganic arsenic.