Dose-response relationship between urinary cadmium and metallothionein in a Japanese population environmentally exposed to cadmium.
The dose-response relationship between cadmium (Cd) exposure and renal dysfunction, as measured by urinary Cd and metallothoinein (MT), was evaluated in a population living in the Kakehashi River basin, a Cd-polluted area in Japan. Morning urine specimens were collected from 1397 men and 1713 women who were 50 years or older. In addition, urine specimens were collected from a control population consisting of 110 men and 130 women. The 97.5% upper limits for MT in the control population were used to determine the prevalence rates for MT-uria at various urinary Cd concentrations. Probit linear regression analysis showed significant dose-response relationships between MT and Cd. In the control population, prevalence rates of MT-uria for men and women were 1.8 and 3.1%, respectively. Based on the prevalence rates of MT-uria in the control population, the upper limits for the urinary Cd concentrations were calculated from the slopes of the regression lines to be 4.2 and 4.8 micrograms/g creatinine for men and women, respectively. These values, which are similar to those reported previously using urinary beta 2-microglobulin as the indicator, may be of use in establishing the biological threshold, i.e. maximum allowable concentration, for urinary Cd in the environmentally exposed Japanese population.
Kido
T
T
Department of Pharmacology and Toxicology, University of Rhode Island, Kingston 02881-0809.
Shaikh
Z A
ZA
Kito
H
H
Honda
R
R
Nogawa
K
K
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002104:Cadmium / Q000652:urine*; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008668:Metallothionein / Q000652:urine*; D008875:Middle Aged; D012044:Regression Analysis; D012737:Sex Factors
D002104:Cadmium; D008668:Metallothionein