Exposure of women in general populations to lead via food and air in East and Southeast Asia.

BACKGROUND

Despite increasing public concern of the possible health effects of lead (Pb) on general populations, reports on Pb levels in blood (Pb-B) and urine (Pb-B), as well as Pb intake via foods (Pb-F) for many Asian countries are scarce. The present study was initiated to elucidate the extent of non-occupational Pb exposure among general populations in East and Southeast Asia.

METHODS

In 1991-1997, peripheral blood, morning spot urine and 24-hour food duplicate samples were collected from 20 to 50 non-smoking adult women in each of four cities in Southeast Asia and five cities in Mainland China, and two cities each in Japan and Korea. The samples were wet-ashed and then analyzed by inductively coupled plasma mass spectrometry for Pb-B, Pb-U and Pb-F. Measures after logarithmic conversion were subjected to ANOVA and regression analysis.

RESULTS

Geometric mean values in cities in East and Southeast Asia were in ranges of 32-65 microg/L for Pb-B, 2.1-7.5 microg/g cr for Pb-Ucr, and 7-32 microg/day for Pb-F. The values for a combination of two cities of Tokyo and Kyoto, Japan (38 microg/L for Pb-B and 9.3 microg/day for Pb-F) appeared to be lower than the values for other Asian cities, and the values for all Japan (thus including both urban and rural areas) were even lower (19 microg/L for Pb-B and 7.7 microg/day for Pb-F). Comparison of Pb uptake via respiratory and dietary routes showed that Pb via dietary route accounted for 15% of the total in Manila where Pb in air was high (ca. 650 ng/m(3)), whereas it was 54% in Tokyo+Kyoto where Pb in air was low (ca. 75 ng/m(3)).

CONCLUSIONS

When compared internationally, Pb-F and Pb-B in Asia in general are similar to or somewhat higher than the levels in Europe and USA, whereas the levels in Japan are probably lower than the two latter areas. In Asia, Pb-F accounted for 15-54% of all Pb sources, the percentage being variable depending on local conditions especially Pb in atmospheric air.