Axe Santé des Populations et Environnement, Centre de Recherche du CHUQ, Quebec (QC), Canada.
Environ Res. 2011 Nov;111(8):1265-70. doi: 10.1016/j.envres.2011.09.001. Epub 2011 Oct 1.
Aboriginal populations from Quebec (Canada) are exposed to higher mercury levels than southern regions since these populations consume high quantities of fish. Epidemiological evidence suggests a detrimental impact of mercury on cardiovascular risk factors such as heart rate variability (HRV) and blood pressure (BP). The objective of this study was to assess the impact of mercury exposure on BP, resting heart rate (HR) and HRV among Cree adults. Data were collected among 791 adults≥18 years old living in seven communities of the James Bay. Blood mercury and hair levels were used as biomarkers of recent and long-term exposure. BP was measured through a standardised protocol while HRV was derived from a 2-h Holter monitoring assessment. The relationship between mercury and the outcomes was studied using ANOVA and ANCOVA analysis. Geometric mean of blood mercury and hair mercury concentration was 17.0 nmol/L (95%CI: 6.1-44.0) and 2.36 nmol/g (95%CI: 2.09-2.65); respectively. After adjusting for confounders, blood mercury was associated with HRV parameters such as LF (β=0.21, P=0.0002), HF (β=0.15, P=0.004) and LF/HF (β=0.06, P=0.003). Similar associations were observed with hair mercury. In contrast, no significant association was observed between blood mercury or hair mercury and BP after adjusting for confounders. In conclusion, mercury exposure seems to affect HRV among Cree adults even after considering fish nutrients (n-3 fatty acids and selenium) and other contaminants (lead and polychlorinated biphenyls) that are also present in the traditional diet of this population.
魁北克（加拿大）的原住民群体摄入大量鱼类，因此其体内的汞含量高于南部地区。流行病学证据表明，汞会对心血管风险因素产生不良影响，如心率变异性（HRV）和血压（BP）。本研究旨在评估汞暴露对克里族成年人的 BP、静息心率（HR）和 HRV 的影响。数据采集于居住在詹姆斯湾七个社区的 791 名年龄在 18 岁及以上的成年人。血液汞和头发汞水平被用作近期和长期暴露的生物标志物。血压通过标准化协议进行测量，而 HRV 则来自 2 小时动态心电图监测评估。使用方差分析和协方差分析研究了汞与结果之间的关系。血液汞和头发汞浓度的几何平均值分别为 17.0 nmol/L（95%CI：6.1-44.0）和 2.36 nmol/g（95%CI：2.09-2.65）。在调整混杂因素后，血液汞与 HRV 参数（如 LF：β=0.21，P=0.0002；HF：β=0.15，P=0.004；LF/HF：β=0.06，P=0.003）呈正相关。头发汞也观察到类似的关联。相反，在调整混杂因素后，血液汞或头发汞与 BP 之间没有显著关联。总之，即使考虑到克里族传统饮食中也存在的其他污染物（如铅和多氯联苯）以及鱼类营养素（n-3 脂肪酸和硒），汞暴露似乎仍会影响克里族成年人的 HRV。
