RESUMO
<p><b>OBJECTIVE</b>The purpose of this study was to investigate the blood lead level of 3 - 5 year old children living in the cities in China and to provide scientific data for making policy on environmental lead pollution for children health protection.</p><p><b>METHODS</b>Six thousand five hundred and two vein blood samples from 3 - 5 year old children in nineteen cities of nine provinces were sampled. Inductively coupled plasma-mass spectrometry (ICP-MS) were employed to determine lead level in whole blood after microwave digestion for sample preparation and questionnaire survey was also performed. Data were analyzed with multiple regression on factors which affecting blood lead levels.</p><p><b>RESULTS</b>Results showed that mean blood lead level was 88.3 micro g/L for 3 - 5 year old children living in the cities in China and mean blood lead level of boys (91.1 micro g/L) was higher than that of girls (87.3 micro g/L). Twenty-nine point nine one per cent of the children's blood lead level exceeded 100 micro g/L. The research finding showed: (1) higher blood lead levels had negative effects on children's physical growth, language ability etc. (2) behavior of parents had certain effects on children's blood lead levels. (3) blood lead levels of children were affected by unhealthy habits.</p><p><b>CONCLUSIONS</b>Problem of childhood lead poisoning in China has become more serious. During the past ten years, blood lead levels of children has been increased in China while decreasing in developed countries. Blood lead levels of children in China are higher than that of developed countries, which called for special concern by government and society.</p>