1.Blood lead measurements in samples collected from 660 London schoolchildren during 1991 to 1992 suggest that the blood lead values in children in the U.K. are decreasing.
2.Geometric mean values for blood lead were 0.18 (range 0.05–0.71) ;μmol/l [3.7 (1.0–15.0) ;μg/dl]. Analysis of variance showed differences between ethnic groups, sex and schools. An age-matched subset of 148 children was compared with 136 children from an earlier study in 1986 and 1987. Trend analysis of the geometric mean lead values showed a negative slope (b = -0.484, P< 0.0001), with maximum values of 0.81, 1.00, 0.71 and 0.43 ;μmol/l (17, 21, 15 and 9 ;μg/dl) for the years 1986, 1987, 1991 and 1992 respectively.
3.It is recommended that children in the U.K. being investigated for anaemia, pica, recurrent abdominal pain or a high-risk environment should have blood lead values measured and that the action level for blood lead in children should be decreased from 1.19 ;μmol/l to 0.48 ;μmol/l (from 25 ;μg/dl to 10 ;μg/dl).
4.Guidance is offered to clinicians and other health professionals investigating excessive lead exposure.