title: Evaluation of factors associated with cadmium exposure and kidney function in the general population.
abstract: Cadmium (Cd) is a nonessential toxic metal which is widely distributed in the environment. The general population is exposed to low levels of Cd and the kidney is the organ most sensitive to Cd toxicity. This study was performed to simultaneously evaluate Cd exposure, kidney function, and oxidative stress biomarkers in the general population. A total of 643 adults were interviewed to document demographic characteristics, lifestyles, past-medical history, and diet during the last 24 h. We estimated daily Cd intake based on the diet of study subjects who had not been exposed to Cd occupationally. Whole blood and urine samples were collected and analyzed to determine Cd concentrations and kidney function indices (β₂ -microglobulin [β₂-MG], N-acetyl-β-D-glucosaminidase [NAG], metallothionein [MT]). The oxidative stress index (malondialdehyde [MDA]) was determined from the urine. The daily Cd intake from diet was established as 7.07 μg/day. The mean concentration of Cd measured in the blood was 1.22 μg/L and urine was 0.95 μg/g creatinine. The concentrations of Cd in blood and urine were higher in females than in males. The blood levels of Cd were affected by sex, age, and smoking, and urine Cd was influenced by sex, age, and blood Cd. The urine Cd was positively correlated with MT, NAG activity, and MDA in females, but with NAG only in males. The blood Cd was associated with MT in males. Increased NAG activity was observed when Cd in urine reached 1.0 μg Cd/g creatinine and was also affected by age, hypertension, and diabetes mellitus. Urinary MT only responded to Cd in urine or blood. In summary, exposure to Cd in the general population was influenced by various factors including sex, age, and smoking habits. Such exposure might eventually cause tubular damage in the kidneys through the oxidative stress mechanism, and females might be more susceptible than males to Cd exposure under the environment.
authors.affiliation: Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul 156-756, Korea.
authors.forename: Mingai
authors.initials: M
authors.lastname: Huang
authors.forename: Seong-Jin
authors.initials: SJ
authors.lastname: Choi
authors.forename: Dong-Won
authors.initials: DW
authors.lastname: Kim
authors.forename: Na-Young
authors.initials: NY
authors.lastname: Kim
authors.forename: Hye-Sun
authors.initials: HS
authors.lastname: Bae
authors.forename: Seung-Do
authors.initials: SD
authors.lastname: Yu
authors.forename: Dae-Seon
authors.initials: DS
authors.lastname: Kim
authors.forename: Heon
authors.initials: H
authors.lastname: Kim
authors.forename: Byung-Sun
authors.initials: BS
authors.lastname: Choi
authors.forename: Il-Je
authors.initials: IJ
authors.lastname: Yu
authors.forename: Jung-Duck
authors.initials: JD
authors.lastname: Park
mesh_terms: D000118:Acetylglucosaminidase / Q000097:blood / Q000652:urine; D000328:Adult; D000367:Age Factors; D000368:Aged; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002104:Cadmium / Q000097:blood / Q000633:toxicity* / Q000652:urine; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology; D007677:Kidney Function Tests; D008297:Male; D008315:Malondialdehyde / Q000652:urine; D008668:Metallothionein / Q000097:blood / Q000652:urine; D008875:Middle Aged; D018384:Oxidative Stress; D012737:Sex Factors; D001613:beta 2-Microglobulin / Q000097:blood / Q000652:urine
chemical_list: D015415:Biomarkers; D001613:beta 2-Microglobulin; D002104:Cadmium; D008315:Malondialdehyde; D008668:Metallothionein; D003404:Creatinine; D000118:Acetylglucosaminidase