title: Association of cadmium in urine and blood with age in a general population with low environmental exposure.
abstract: A recent study reported a nonlinear and nonmonotonic relationship between urinary cadmium (U-Cd) and age and questioned the long-held view that U-Cd is a reliable biomarker of Cd body burden at low exposure levels. In order to reassess the significance of U-Cd as biomarker of Cd body burden, we studied the lifetime trend of U-Cd as functions of diuresis in a cross-sectional study. Cadmium was measured with an inductively coupled plasma mass spectrometer (ICP-MS) for the general population taking part in the Metals and Health Survey in Jiangsu (MHSJ), China, with ages ranging from 2.8 to 86.8 years (n = 1235). Variations in U-Cd and B-Cd with age were modeled using natural cubic splines. Factors associated with U-Cd were analyzed with Pearson correlation and linear regression models. As results, nonsmoking men had peak U-Cd at approximately 60 years, after which it decreased. In nonsmoking women, U-Cd increased from 2.8 years to 50 years, then leveled off. In both genders, B-Cd increased from birth to approximately 30 years and then leveled off. U-Cd, expressed in per liter, was consistently associated with B-Cd and U-creatinine, regardless of smoking status. U-Cd and B-Cd were not significantly higher in former smokers than never smokers. Our study suggests that individual U-Cd level are correlated with B-Cd and U-creatinine, and needed to be appropriately adjusted for B-Cd and U-creatinine, when it is used for a biomarker of kidney burden of Cd.
authors.affiliation: Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210009, Jiangsu, China. Electronic address: njmu_sunhong@hotmail.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Sun
authors.affiliation: Changshu Center for Disease Prevention and Control, Suzhou 510000, Jiangsu, China.
authors.forename: Dongyue
authors.initials: D
authors.lastname: Wang
authors.affiliation: Changshu Center for Disease Prevention and Control, Suzhou 510000, Jiangsu, China.
authors.forename: Zhengyuan
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210009, Jiangsu, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Ding
authors.affiliation: Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210009, Jiangsu, China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Chen
authors.affiliation: Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210009, Jiangsu, China. Electronic address: cdcxy@vip.sina.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, Jiangsu, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Huang
authors.affiliation: Columbia University Mailman School of Public Health, NY 10032, USA.
authors.forename: Deliang
authors.initials: D
authors.lastname: Tang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001822:Body Burden; D002104:Cadmium / Q000097:blood* / Q000652:urine*; D002648:Child; D002675:Child, Preschool; D002681:China; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000032:analysis*; D004785:Environmental Pollutants / Q000097:blood* / Q000652:urine*; D005260:Female; D006306:Health Surveys; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D015415:Biomarkers; D004785:Environmental Pollutants; D002104:Cadmium; D003404:Creatinine
keywords: Biomarker; Blood cadmium; Cadmium body burden; Environmental exposure; Urinary cadmium