中文摘要：

建立了微波萃取-原子荧光光谱法测定海鸟生物粪中的甲基汞测量方法。优化了显著影响微波萃取甲基汞的两个因素：萃取温度和盐酸用量。最终确定了120℃和200μL6mol·L-1盐酸介质为最佳萃取条件。此条件下测定的生物标准参考物质人发粉的相对标准偏差为0.74%,回收率大于90%,测定的海鸟生物粪样品相对标准偏差为6.61%,回收率为90%。微波辅助萃取和原子荧光光谱的联用,具有操作简单,高灵敏度,低检出限,低成本等一系列优点,适用于生物粪样品中痕量成分甲基汞的快速分离与分析。采用此方法分析了西沙群岛古鸟粪颗粒和现代新鲜鸟粪中甲基汞含量,发现大量海鸟粪的输入将会对偏远的西沙群岛生态环境造成严重的汞污染。

英文摘要：

The analytical method for the determination of methylmercury in seabird excrements was established using atomic fluorescence spectrometry coupled with microwave-assisted extraction. In general, temperature and hydrochloric amount are the most important influencing factors on the extraction of MeHg in the samples, and the present paper optimized these two parameters. The result showed that 120 ℃ and 200 μL 6 mol·L-1 hydrochloric acid are the best extraction conditions. Under these experimental conditions, the relative standard deviation （RSD） values of reduplicative analyses on standard reference material （human hair powder） and the same seabird excrement sample were 0.74% and 6.61% respectively, and their percent recoveries were over 90%. The combination of microwave-assisted extraction and atomic fluorescence spectrometry has many advantages such as simple operation, high sensitivity, low detection limit and low cost, therefore, it is suitable for rapid separation and analysis of trace methylmercury composition in the biological guanos. Using this method, we analyzed the methylmercury contents in the ancient and fresh seabird droppings taken from Xisha Islands of South China Sea, and the result showed that the Xisha guanos were rich in methylmercury and the large input of seabird guanos will cause serious environmental contamination in the remote island ecosystem of Xisha Islands.