水产品中甲基汞的快速检测与甲基汞在鲫鱼体内富集规律研究

Rapid determination of methylmercury in aquatic product and study on the enrichment of methylmercury in crucian

建立了液相色谱-电感耦合等离子体质谱法(HPLC-ICP-MS)测定水产品中甲基汞的快速分析方法,实验以甲醇/水/巯基乙醇(V/V/V=5/95/0.5)的混合液为甲基汞提取液,以微波辅助提取为手段,整个前处理过程不到半小时,以甲醇/水/巯基乙醇(V/V/V=5/95/0.1)为流动相,采用C8柱(30 mm×3 mm,3μm),在1.0 mL/min流速下,甲基汞和汞离子在6 min内实现完全分离,两者检出限分别为0.20μg/L和0.50μg/L,相关系数分别为0.9999和0.9993,相对标准偏差RSD≤5.6%,在鱼样中分别添加低(0.20μg/L)、中(1.0μg/L)、高(2.0μg/L)三个浓度的甲基汞标准溶液,回收率为88.0%～99.5%,满足分析测试要求。采用建立的方法研究了鲫鱼对甲基汞的吸收规律,结果表明,随着饲养水域中甲基汞含量的升高以及饲养时间的增加,鲫鱼体内甲基汞的富集越来越显著。

A method was established for rapid determination of methylmercury （MeHg） in aquatic product using high performance liquid chromatography inductively coupled plasma-mass spectrometry. A microwave-assisted extraction procedure was adopted for the extraction of MeHg from aquatic product with the solution containing 0. 5% （v/v） 2-mercaptoethanol and 5% （v/v） methanol, and the whole pretreatment was completed less than half an hour. Inorganic mercury（ Hg^2＋） and MeHg were well resolved within six minutes with a C8 column （30 mm× 3 mm,3 μm） as the stationary phase and the solution containing 0. 1% （v/v） 2-mercaptoethanol and 5% （v/v） methanol as the mobile phase at a flow rate of 1.0 mL/min. Detection limits of MeHg and Hg^2＋ were 0. 20μg/L and 0. 50μg/L and the correlation coefficients were 0. 9999 and 0. 9993, respectively. RSDs were less than 5.6% and three known concentrations of MeHg with low （0. 20μg/L）, middle （ 1.0μg/L） and high （2. 0bLg/L） were added into the fish, and the recoveries were 88.0% -99.0%. The method was used to study the enrichment of MeHg in the crucian. The results show that MeHg was accumulated significantly in the crucian with the increase of the concentration of MeHg in the water environment and the feeding time.