Biomarkers of nephrotoxicity in children environmentally exposed to lead in Poland

Nephropathy has been reported in children with overt lead intoxication. Only recently low-level lead exposure has been associated with renal effects, especially with regard to tubular function. The objective of the present study was to investigate the relation between lead exposure and renal function in children in the Katowice region, an industrial area in Poland. This cross-sectional study involved 157 children, aged 4–14 years. Blood lead concentration was used as an index of lead exposure. Glomerular filtration rate was estimated using the height adjusted serum creatinine calculation (crea-GFR) and measurement of cystatin C in serum. The renal tubular function was evaluated by measuring the urinary concentration of protein HC. The median blood lead concentration was 0.35 μmol/L (72 μg/L) with a range of 0.09–1.36 μmol/L. Crea-GFR (n = 143) decreased significantly (p = 0.002) with increasing concentrations of lead in the blood. Serum cystatin C (n = 84) increased with blood lead (p = 0.004). There was an association (p = 0.002) between blood lead and urinary concentration of protein HC (n = 49). In summary, the present findings indicate that the association between blood lead and the markers of renal function on both a glomerular and a tubular level may be caused by environmental lead exposure. Copyright © 1999 John Wiley & Sons, Ltd.