BioMetals 17: 559–565, 2004. © 2004 Kluwer Academic Publishers. Printed in the Netherlands. 559 Effects on the prostate of environmental cadmium exposure – A cross-sectional population study in China Xiangbin Zeng 1 , Taiyi Jin 1,2,∗ , Xuezi Jiang 1 , Qinhu Kong 3 , Tingting Ye 4 & Gun- nar F. Nordberg 2 1 Department of Occupational Health, School of Public Health, Fudan University 200032 Shanghai, PR China; 2 Environmental Medicine, Umeå University, S-901 87 Umeå, Sweden; 3 Institute of Environmental Health, Zhejiang Academy of Medical Science, Hangzhou, PR China; 4 Department of Preventive Medicine, School of Public Health, Fudan University, Shanghai, 200032 Shanghai, PR China; ∗ Author for correspondence (E-mail: tyjin@shmu.edu.cn) Key words: cadmium, digital rectal examination, human population, prostate pathological changes, prostate- specific antigen, sex hormone Abstract To explore possible effects of environmental cadmium exposure on prostate in humans, and the possible relation- ship of serum sex hormones to occurrence of clinic signs of tissue changes in the prostate, a case-control study was undertaken in the southeast part of China in 1998. A total of 297 male volunteers from a control area and two cadmium-polluted areas were included as subjects in this study. All the subjects were required to answer a questionnaire and to undergo a complete physical examination including digital-rectal examination (DRE). Blood and urine samples were collected. Serum total prostate specific antigen (PSA), total serum testosterone (T), follicle stimulating hormone (FSH) and luteinizing hormone (LH) were measured by radioimmunoassay and enzymeimmunoassay method, respectively. The data of urinary cadmium (U-Cd) and blood cadmium (B-Cd) were obtained by atomic absorption spectrometry (AAS) as an indicator of cadmium body burden. Statistical analysis was applied to investigate a possible relation between cadmium exposure and prostate pathological changes. The results show that there is a clear dose-response relationship between cadmium exposure and the prevalence of cases with abnormal PSA. The blood cadmium content in cases with positive DRE was significantly higher than that of subjects with negative DRE (P< 0.05). Significant differences in the level of FSH between cases with positive DRE and the normal subjects were also noted (P < 0.05). These results indicate that chronic environmental cadmium exposure is associated with injuries to human prostate. A possible relationship to changes in circulating sex hormones needs further investigation. Introduction Cadmium (Cd) is a toxic transition metal with a wide variety of adverse effects on humans (Nordberg 1992). There are several sources of human exposure to cadmium, including occupational exposure, envir- onmental exposure and smoking. Now, cadmium gets increasing concern because many studies in human populations and in animals indicate that cadmium is a potential carcinogen to human prostate (Ross et al. 1987; Van der Gulden et al. 1995; Waalkes et al. 1992). Cadmium has been designated as a human carcinogen based on its carcinogenicity to the lung (IARC 1993; Ades & Kazantzis 1988; Sorahan 1987). Some studies (Ross et al. 1987; Van der Gulden et al. 1995) have shown a link between occupational cadmium exposure and prostate cancer, but evidence are not convincing and complete enough. There are also many other studies (Sorahan & Waterhouse 1983; Armstrong & Kazantzis 1983) which showed different results and not supported the viewpoint that cadmium exposure can result in prostate cancer. Although oc-