2005 Fiscal Year Final Research Report Summary
A follow-up study on renal tubular dysfunction in inhabitants of a cadmium-polluted area : Considerations for risk assessment for environmental exposure to cadmium
Project/Area Number |
15510025
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Environmental impact assessment/Environmental policy
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Research Institution | University of Toyama (2005) Toyama Medical and Pharmaceutical University (2003-2004) |
Principal Investigator |
KATOH Terutaka University of Toyama, Department of Medicine, Assistant professor, 医学部, 助手 (80115162)
|
Co-Investigator(Kenkyū-buntansha) |
TERANISHI Hidetoyo University of Toyama, Associate professor, 医学部, 助教授 (40115184)
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Project Period (FY) |
2003 – 2005
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Keywords | Cadmium / Environmental pollution / Itai-itai disease / Proximal renal tubular dysfunction / Cadmium content in rice / Follow-up study / Osteomalacia |
Research Abstract |
1)A seventeen-year follow-up study was carried out to elucidate the progress of proximal renal tubular dysfunction (PRTD) in inhabitants of the cadmium (Cd)-polluted Jinzu River basin in Toyama. Significantly increased levels of urinary excretion of β_2-microglobulin (β_2-MG) and α_1-MG indicate that PRTD was irreversible and progressive, despite the fact that Cd exposure had decreased over the past 17 years. 2)Bone metabolism in Cd-induced PRTD has not been fully examined in middle-aged women of the Cd-polluted Jinzu River basin. Clinical and biochemical examination was carried out in 8 women with β_2-MGuria exceeding 1 mg/g Cr and were born from 1934 on. Of the 8 women, three subjects were diagnosed as PRTD, and two of them had vertebral fractures, and moreover, one of these two subjects suffered a fracture of the right femoral neck. 3)A twenty-year clinical review of 12 patients (6 women and 6 men) with β_2-MGuria showed that, in women, subjects having β_2-MGuria less than 1 mg/g Cr in the initial study did not develop PRTD but subjects having β_2-MGuria more than 30 mg/g Cr developed chronic renal failure after 20 years. One patient was diagnosed as osteomalacia showing hypophosphatemia, increased serum alkaline phosphatase activity and pseudo fracture of right femur. In men, subjects having β_2-MGuria less than 3 mg/g Cr in the initial study developed PRTD because of having bladder cancer or ureteral stone as a complication. 4)Urinary Cd excretion level, an indicator of Cd accumulation in the kidney, significantly increased with increased duration (years) of residence in the Cd-polluted Jinzu River basin in inhabitants born between 1946 and 1955. There was no case of β_2-MGuria in both men and women, in contrast to the high prevalence of β_2-MGuria observed in older generations.
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Research Products
(10 results)