Cheng Liu, Mao Yu-xiang, Ma Bing-juan, Wang Mei
Huan Jing Ke Xue. 2015 Jan;36(1):121-9.
In order to investigate the occurrence status of mercury in Xiaolangdi Reservoir, water, surface sediments, pore water and fish samples were collected and analyzed for the contents of total mercury (THg) and methylmercury (MeHg). Cold vapor atomic fluorescence spectrometry and aqueous phase ethylation derivatization-gas chromatography-atomic fluorescence spectrometry methods were used for the analysis of THg and MeHg, respectively. Bioaccumulation of THg in fish of Xiaolangdi Reservoir was then discussed. It was found that THg contents in water were 0.71-1.42 ng x L(-1) and 0.90-2.49 ng x L(-1) during dry and wet seasons, respectively, while the MeHg content in water was below the method detection limit. The THg content in water during both seasons could meet the requirement of Class I criterion of national surface water environmental quality standard (GB 3838-2002). The THg contents in sediments were 95.66-172.52 ng x g(-1) and 51.74-90.42 ng x g(-1), while the MeHg contents in the corresponding sediment samples were 0.18-0.39 ng x g(-1) and 0.09-0.26 ng x g(-1) for dry and wet seasons, respectively. The ratios of MeHg/THg in sediment were relatively small in comparison to those in other aqueous systems. This might be attributed to the high dissolved oxygen content of bottom water and low organic carbon content of the sediments. The THg concentrations in pore water of sediments were 5.46-41.04 ng x L(-1) and 4.27-9.49 ng x L(-1), and the MeHg concentrations were 0.07-1.01 ng x L(-1) and 0.09-0.99 ng x L(-1), respectively. The THg concentration was significantly higher than that of the overlying water, indicating the diffusion of Hg from the sediment to the water. The THg concentration in fish muscle tissues varied from 43.47 to 304.98 ng x g(-1), while the MeHg concentration varied from 10.77 to 265.23 ng x g(-1). The MeHg content in fish muscle tissues could meet the requirement of national food safety standards( GB 2762-2012) (Non carnivorous fish 500 ng x g(-1), Carnivorous fish 1 000 ng x g(-1)). The bioaccumulation factors of THg were 1.3 x 10(5) for bighead carp, 9.3 x 10(4) for barracuda, 4.7 x 10(4) for crucian carp, 5.0 x 10(4) for sharpbelly, 1.7 x 10(5) for yellow catfish, and 3.9 x 10(4) for arch fish, respectively.
为调查小浪底水库汞的赋存状况，采集了水、表层沉积物、孔隙水和鱼类样品，分析其中总汞（THg）和甲基汞（MeHg）的含量。分别采用冷原子荧光光谱法和水相乙基化衍生-气相色谱-原子荧光光谱法分析THg和MeHg。进而探讨了小浪底水库鱼类中THg的生物累积情况。结果表明，枯水期和丰水期水体中THg含量分别为0.711.42 ng·L-1和0.902.49 ng·L-1，而水体中MeHg含量低于方法检出限。两季水体中THg含量均满足国家地表水环境质量标准（GB 3838—2002）Ⅰ类标准要求。沉积物中THg含量分别为95.66172.52 ng·g-1和51.7490.42 ng·g-1，相应沉积物样品中MeHg含量枯水期和丰水期分别为0.180.39 ng·g-1和0.090.26 ng·g-1。沉积物中MeHg/THg比值相较于其他水体系统相对较小。这可能归因于底层水溶解氧含量高和沉积物有机碳含量低。沉积物孔隙水中THg浓度分别为5.4641.04 ng·L-1和4.279.49 ng·L-1，MeHg浓度分别为0.071.01 ng·L-1和0.090.99 ng·L-1。THg浓度显著高于上覆水，表明汞从沉积物向水体扩散。鱼肌肉组织中THg浓度在43.47304.98 ng·g-1之间，MeHg浓度在10.77265.23 ng·g-1之间。鱼肌肉组织中MeHg含量满足国家食品安全标准（GB 2762—2012）要求（非肉食性鱼类500 ng·g-1，肉食性鱼类1 ０００ ng·g-1）。鳙鱼、梭鱼、鲫鱼、餐条、黄颡鱼和赤眼鳟的THg生物累积因子分别为1.3×105、9.3×104、4.7×104、5.0×104、1.7×105和3.9×104。
