Analytical Cytology Laboratory and the Key Immunopathology Laboratory of Guangdong Province, Shantou University Medical College, Shantou 515041, China.
Environ Monit Assess. 2011 Jun;177(1-4):343-51. doi: 10.1007/s10661-010-1638-6. Epub 2010 Aug 17.
This study aimed to determine the levels of placental cadmium (PCd) and cord blood cadmium (CBCd) and the resulting expression of placental metallothionein (MT) in neonates and to investigate cadmium (Cd) exposure levels in neonates and mothers who live in Guiyu, China, an electronic waste (e-waste) pollution site. Among the 423 mothers included in the study from 2004/2005 to 2007, 289 lived in Guiyu (exposed group) and 134 lived in Chaonan, located 10 km away from Guiyu (controls) and had never been exposed to e-waste pollution. CBCd and PCd levels were measured by atomic absorption spectrometry. Placental MT was examined by immunohistochemistry. Information on maternal and neonatal characteristics and exposure conditions was obtained from hospital records and by personal interviews. For the 3 years, the median CBCd was higher for Guiyu neonates than for controls (3.61 vs. 1.25 μg/L), with 25.61% of Guiyu subjects exhibiting a median CBCd that exceeded the safety limit defined by the World Health Organization (5 μg/L), as compared with 14.18% of control neonates (p < 0.01). In Guiyu, the mean PCd was higher than that for controls (0.17 ± 0.48 vs. 0.10 ± 0.11 μg/g, p ≤ 0.01). The high levels of CBCd and PCd were significantly associated with parents' occupational and environmental exposure to e-waste recycling pollutants. Staining for MT was positive and dense for 67.00% (67/100) of Guiyu neonates as compared with 32.69% (17/52) of controls (p < 0.01). Exposure to e-waste recycling pollutants increased Cd exposure in neonates, which was accompanied by increased placental MT expression.
本研究旨在测定胎盘镉（PCd）和脐血镉（CBCd）水平以及由此导致的新生儿胎盘金属硫蛋白（MT）的表达，并调查居住在中国贵屿（电子废物污染区）的新生儿和母亲的镉（Cd）暴露水平。在 2004/2005 年至 2007 年期间纳入的 423 名母亲中，289 名来自贵屿（暴露组），134 名来自距贵屿 10 公里的潮南（对照组），她们从未接触过电子废物污染。采用原子吸收光谱法测定 CBCd 和 PCd 水平。通过免疫组织化学法检测胎盘 MT。从医院记录和个人访谈中获得母婴特征和暴露条件的信息。在这 3 年中，贵屿新生儿的 CBCd 中位数高于对照组（3.61 与 1.25 μg/L），25.61%的贵屿儿童的 CBCd 中位数超过世界卫生组织（5 μg/L）定义的安全限值，而对照组中这一比例为 14.18%（p < 0.01）。在贵屿，PCd 的平均值高于对照组（0.17 ± 0.48 与 0.10 ± 0.11 μg/g，p ≤ 0.01）。CBCd 和 PCd 水平较高与父母职业性和环境性接触电子废物回收污染物密切相关。MT 染色阳性且密集的贵屿新生儿占 67.00%（67/100），而对照组为 32.69%（17/52）（p < 0.01）。接触电子废物回收污染物增加了新生儿的 Cd 暴露，同时伴随着胎盘 MT 表达增加。
