マーケットバスケット調査に基づく食物からの鉛一日曝露量の推計

抄録

Daily dietary exposure level of lead was estimated by market basket survey and low-contamination lead analysis. We collected 151 food samples of 17 food categories at supermarkets in Shizuoka city, Japan, and prepared 17 composites by mixing the food items in each of the categories after pretreatment and cooking. The composite was digested with ultrapure acid in a clean room and lead concentration was measured by ICP mass spectrometry. Lead was detected in all of the composites at the concentration of 0.21 to 124 ng/g fresh weight. Daily dietary exposure level of lead in Tokai district was calculated by multiplying lead concentration with daily intake of each of the 17 food composites, and by summing them all to find 4.69 μg/day. The obtained value is considered reliable because lead was detected in all of the composites: inclusion of "undetectable" composites generally results in uncertainty in daily exposure estimation based on market basket survey. "Algae" composite contributed most to the total daily exposure (28.8 %), which was followed by "Beverage" (13.8 %) and "Vegetable" (12.2 %) in this order. The present result will be valuable in the assessment and management of risk due to lead exposure in Japan.