Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul 156-756, Korea.
Environ Toxicol. 2013 Oct;28(10):563-70. doi: 10.1002/tox.20750. Epub 2011 Jul 22.
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.
镉（Cd）是一种广泛分布于环境中的非必需有毒金属。一般人群接触低水平的镉，而肾脏是对镉毒性最敏感的器官。本研究旨在同时评估一般人群的镉暴露、肾功能和氧化应激生物标志物。对 643 名成年人进行了访谈，以记录人口统计学特征、生活方式、既往病史和过去 24 小时的饮食情况。我们根据未接触职业性镉的研究对象的饮食来估计每日镉摄入量。采集全血和尿液样本进行分析，以确定 Cd 浓度和肾功能指标（β₂-微球蛋白[β₂-MG]、N-乙酰-β-D-氨基葡萄糖苷酶[NAG]、金属硫蛋白[MT]）。尿中测定氧化应激指标（丙二醛[MDA]）。从饮食中确定的每日镉摄入量为 7.07μg/天。血液中 Cd 的平均浓度为 1.22μg/L，尿液为 0.95μg/g 肌酐。女性血液和尿液中的 Cd 浓度高于男性。血液中 Cd 水平受性别、年龄和吸烟影响，尿液中 Cd 水平受性别、年龄和血液中 Cd 水平影响。尿液中 Cd 与女性的 MT、NAG 活性和 MDA 呈正相关，而仅与男性的 NAG 呈正相关。血液 Cd 与男性的 MT 相关。当尿中 Cd 达到 1.0μg Cd/g 肌酐时，观察到 NAG 活性增加，且该活性还受年龄、高血压和糖尿病的影响。尿 MT 仅对尿或血中的 Cd 有反应。总之，一般人群的 Cd 暴露受到性别、年龄和吸烟习惯等多种因素的影响。这种暴露可能最终通过氧化应激机制导致肾脏的肾小管损伤，而且在环境中女性比男性更容易受到 Cd 暴露的影响。
