ENVIRONMENTAL URBAN LEAD-EXPOSURE AND BLOOD LEAD LEVELS IN CHILDREN OF MEXICO-CITY

Lead contamination is now a leading public heath problem in Mexico. Ho wever, there are few data on the lead content of various environmental sources, and little is known about the contribution of these sources to the total lead exposure in the population of children residing in M exico City. We conducted a cross-sectional study in a random sample of 200 children younger than 5 years of age who lived in one of two area s of Mexico City. Environmental samples of floor, window, and street d ust, paint, soil, water, and glazed ceramics were obtained from the pa rticipants' households, as well as blood samples and dirt from the han ds of the children. Blood lead levels ranged from 1 to 31 mu g/dl with a mean of 9.9 eta g/dl (SD 5.8 mu g/dl). Ferry-four percent of the ch ildren 18 months of age or older had blood lead levels exceeding 10 mu g/dl. The lead content of environmental samples was low except in gla zed ceramic. The major predictors of blood lead levels were the lead c ontent of the glazed ceramics used to prepare children's food, exposur e to airborne lead due to vehicular emission, and the lead content of the dirt from the children's hands. We conclude that the major sources of lead exposure in Mexico City could be controlled by adequate publi c health programs to reinforce the use of unleaded gasoline and to enc ourage production and use of unleaded cookware instead of lead-glazed ceramics.