Evaluation of urinary cadmium and lead as markers of background exposure of middle-aged women in Korea: dietary intake as an influential factor

The study was conducted to examine the validity of urinary cadmium (Cd) and lead (Pb) in comparison with the metals in blood as a biological marker of non-occupational exposure of general populations. Participants in four sur vey sites in Korea (107 non-smoking Korean women aged 30-49 years) offered peripheral blood, morning spot urine, and 24-h total food duplicate samples . Analysis of Cd and Pb was accomplished by graphite furnace atomic absorpt ion spectrophotometry. The analyse levels were evaluated on an individual b asis (n = 107) and also on a survey site basis, i.e. in terms of geometric means for the groups in the survey sites (n = 4). Cd in urine (as observed, or after correction for creatinine concentration or a specific gravity) co rrelated with Cd in blood on an individual as well as survey site basis, an d tended to correlate with Cd in food duplicates on the survey site basis. Correlation of Pb in urine with Pb in blood was weaker than that of Cd in u rine with Cd in blood both on the individual and survey site basis. Pb in u rine correlated with Pb in food duplicates either weakly or even negatively when examined on a survey site basis. It was concluded that Cd in urine ca n be most probably employed as a biological marker of environmental Cd expo sure of general population, whereas less support was obtained for Pb in uri ne as an exposure marker. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.