Abstract • 105

Red cell membranes were studied with proper and zond luminescence in 63 children living in large city environments. Children were divided into three groups by their lead (PB) and mercury (Hg) serum levels. Group I: children with elevated serum PB levels (0.125 +/- 0.004 mg/l) and Hg levels (0.068 +/- 0.005 mg/l); II: children with elevated Pb serum levels (0.006 mg/l); III: children with elevated Hg levels (0.088 +/- 0.008 mg/l). Each group was divided into 2 subgroups: with and without iron deficiency anemia (IDA).

Children in groups I and II showed disturbances of microviscosity of red cell membrane lipid bilayers by lipofilic fluorescent zond. These resulted from changes of cholesterol levels, lipid superoxidation, or disturbances of protein-lipid interactions. Next, we examined the proper (protein) fluorescence of red cell membranes. We found no significant differences between the study and control groups. A direct correlation existed between proper luminescence of protein membranes and Pb serum levels (r1= 0.822, p1 < 0.01; r2 = 0.910, p2 < 0.01). No direct correlation was found between proper luminescence and Pb serum levels.

In conclusion, lipid bilayer microviscocity of red cell membranes is decreased in children exposed to tI NM tI TÄ; nÜ OCZL & NM OCZLNDZ f4d. Without significant differences between the Pb and Hg groups, Pb appears to be the offending agent.