title: Impairment of renal function with increasing blood lead concentrations in the general population. The Cadmibel Study Group.
abstract: BACKGROUND
  Nephropathy is known to occur in persons with heavy exposure to lead. Whether exposure to lead in the general population leads to impaired renal function is not known.
  
  
  METHODS
  We studied renal function and indexes of lead exposure in a random population sample of 965 men and 1016 women (age range, 20 to 88 years). In all the subjects we measured creatinine clearance and blood concentrations of lead and zinc protoporphyrin (an indirect measure of blood lead level).
  
  
  RESULTS
  The mean (+/- SD) creatinine clearance rate was 99 +/- 30 ml per minute in the men and 80 +/- 25 ml per minute in the women. In the men the geometric mean blood lead concentration was 114 micrograms per liter (0.55 mumol per liter) (range, 23 to 725 micrograms per liter [0.11 to 3.5 mumol per liter]), and in the women 75 micrograms per liter (0.36 mumol per liter) (range, 17 to 603 micrograms per liter [0.08 to 2.9 mumol per liter]); the zinc protoporphyrin values in blood averaged 1.0 and 1.1 micrograms per gram of hemoglobin, respectively. The creatinine clearance rate was inversely correlated with blood lead and zinc protoporphyrin values in the men and the women both before and after adjustments for age, bodymass index, and diuretic treatment. A 10-fold increase in blood lead concentration was associated with a reduction of 10 to 13 ml per minute in creatinine clearance. We also found a positive correlation between serum beta 2-microglobulin (which is inversely related to the glomerular filtration rate) and blood lead in men, between serum beta 2-microglobulin and zinc protoporphyrin in both sexes, and between serum creatinine and zinc protoporphyrin in men.
  
  
  CONCLUSIONS
  Exposure to lead may impair renal function in the general population. The alternative hypothesis that renal impairment may lead to an increase in the blood lead concentration cannot be excluded, however.
authors.affiliation: Hypertension and Cardiovascular Rehabilitation Unit, University of Leuven, Belgium.
authors.forename: J A
authors.initials: JA
authors.lastname: Staessen
authors.forename: R R
authors.initials: RR
authors.lastname: Lauwerys
authors.forename: J P
authors.initials: JP
authors.lastname: Buchet
authors.forename: C J
authors.initials: CJ
authors.lastname: Bulpitt
authors.forename: D
authors.initials: D
authors.lastname: Rondia
authors.forename: Y
authors.initials: Y
authors.lastname: Vanrenterghem
authors.forename: A
authors.initials: A
authors.lastname: Amery
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003404:Creatinine / Q000097:blood; D004781:Environmental Exposure; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D007854:Lead / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011524:Protoporphyrins / Q000097:blood; D012044:Regression Analysis; D001613:beta 2-Microglobulin / Q000032:analysis
chemical_list: D011524:Protoporphyrins; D001613:beta 2-Microglobulin; C017803:zinc protoporphyrin; D007854:Lead; D003404:Creatinine