TRANSFER OF LEAD FROM LEAD-GLAZED CERAMICS TO FOOD

Recent studies have shown a clear correlation between the use of lead- glazed ceramicware for cooking or food preparation and elevated blood lead levels. Two lots of lead-glazed ceramic bowls, each from a single manufacturing and firing lot were used to measure the sequential leac hing of lead into salsa (an acidic food) and beans (a neutral food) st ored or cooked in the bowls. The USFDA acetic acid extraction assay wa s also repeatedly performed on these bowls. The results of the USFDA e xtraction test were highly variable with levels ranging from 200 to mo re than 2,000 ppm (regulatory level for rejection is 2 ppm). The level s extracted declined rapidly but the rates were variable. Leaching of lead into salsa (pH = 4.8) was variable and ranged from 8 to greater t han 500 ppm. Sequential extractions using salsa yielded variable but d eclining lead levels. Cooking beans with water in the bowls did not ca use substantial leaching (levels between 3 and 8 ppm) and sequential c ooking did not show any significant decline over IO cycles. The result s indicate substantial variability in leaching of lead into foods stor ed or cooked in lead-glazed ceramicware.