Hangzhou Center for Disease Control and Prevention, Hangzhou 310021, PR China.
BMC Public Health. 2011 Apr 12;11:224. doi: 10.1186/1471-2458-11-224.
Occupational exposure to chromium compounds may result in adverse health effects. This study aims to investigate whether low-level hexavalent chromium (Cr(VI)) exposure can cause DNA damage in electroplating workers.
157 electroplating workers and 93 control subjects with no history of occupational exposure to chromium were recruited in Hangzhou, China. Chromium levels in erythrocytes were determined by graphite furnace atomic absorption spectrophotometer. DNA damage in peripheral lymphocytes was evaluated with the alkaline comet assay by three parameters: Olive tail moment, tail length and percent of DNA in the comet tail (tail DNA%). Urinary 8-OHdG levels were measured by ELISA.
Chromium concentration in erythrocytes was about two times higher in electroplating workers (median: 4.41 μg/L) than that in control subjects (1.54 μg/L, P < 0.001). The medians (range) of Olive tail moment, tail length and tail DNA% in exposed workers were 1.13 (0.14-6.77), 11.17 (3.46-52.19) and 3.69 (0.65-16.20), and were significantly higher than those in control subjects (0.14 (0.01-0.39), 3.26 (3.00-4.00) and 0.69 (0.04-2.74), P < 0.001). Urinary 8-OHdG concentration was 13.65 (3.08-66.30) μg/g creatinine in exposed workers and 8.31 (2.94-30.83) μg/g creatinine in control subjects (P < 0.001). The differences of urinary 8-OHdG levels, Olive tail moment, tail length and tail DNA% between these two groups remained significant (P < 0.001) even after stratification by potential confounding factors such as age, gender, and smoking status. Chromium exposure was found to be positively associated with chromium levels in erythrocytes, urinary 8-OHdG levels, Olive tail moment, tail length and tail DNA%. Positive dose-response associations were also found between chromium levels in erythrocytes and Olive tail moment, tail length and tail DNA%.
The findings in this study indicated that there was detectable chromium exposure in electroplating workers. Low-level occupational chromium exposure induced DNA damage.
职业性接触铬化合物可能导致不良健康影响。本研究旨在探讨六价铬（Cr(VI)）低水平暴露是否会导致电镀工人的 DNA 损伤。
在中国杭州，共招募了 157 名电镀工人和 93 名无铬职业接触史的对照者。采用石墨炉原子吸收分光光度法测定红细胞中铬的含量。通过碱性彗星试验，用 3 个参数评估外周血淋巴细胞的 DNA 损伤：Olive 尾矩、尾长和彗星尾 DNA%（尾 DNA%）。用 ELISA 法测定尿 8-OHdG 水平。
电镀工人的红细胞铬浓度（中位数：4.41μg/L）约为对照组（1.54μg/L，P＜0.001）的两倍。暴露组的 Olive 尾矩、尾长和尾 DNA%中位数（范围）分别为 1.13（0.14-6.77）、11.17（3.46-52.19）和 3.69（0.65-16.20），明显高于对照组（0.14（0.01-0.39）、3.26（3.00-4.00）和 0.69（0.04-2.74），P＜0.001）。暴露组尿 8-OHdG 浓度为 13.65（3.08-66.30）μg/g 肌酐，对照组为 8.31（2.94-30.83）μg/g 肌酐（P＜0.001）。即使在分层考虑年龄、性别和吸烟状况等潜在混杂因素后，两组间尿 8-OHdG 水平、Olive 尾矩、尾长和尾 DNA%的差异仍具有统计学意义（P＜0.001）。铬暴露与红细胞铬水平、尿 8-OHdG 水平、Olive 尾矩、尾长和尾 DNA%呈正相关。红细胞铬水平与 Olive 尾矩、尾长和尾 DNA%之间也存在正剂量反应关系。
本研究表明电镀工人存在可检测的铬暴露，低水平职业性铬暴露可导致 DNA 损伤。
