Institut de Ciències del Mar (ICM-CSIC), Passeig Marítim de la Barceloneta 37-49, 08003 Barcelona, Catalunya, Spain.
Sci Total Environ. 2013 Jan 1;442:329-35. doi: 10.1016/j.scitotenv.2012.10.036. Epub 2012 Nov 22.
A number of studies have found high levels of mercury (Hg) in deep-sea organisms throughout the world's oceans, but the underlying causes are not clear as there is no consensus on the origin and cycling of Hg in the ocean. Recent findings suggested that Hg accumulation may increase with increasing forage depth and pointed to the deep-water column as the origin of most Hg in marine biota, especially its organic methylmercury (MeHg) form. In the present study, we determined the total mercury (THg) levels in 12 deep-sea fish species and a decapod crustacean and investigated their relationship with the species' nitrogen stable isotope ratio (δ(15)N) as an indicator of their trophic level, average weight and habitat depth. THg levels ranged from 0.27 to 4.42 μg/g w.w. and exceeded in all, except one species, the recommended 0.5 μg/g w.w. guideline value. While THg levels exhibited a strong relationship with δ(15)N values and to a lesser extent with weight, the habitat depth, characterized as the species' depth of maximum abundance (DMA), had also a significant effect on Hg accumulation. The fish species with a shallower depth range exhibited lower THg values than predicted by their trophic level (δ(15)N) and body mass, while measured THg values were higher than predicted in deeper-dwelling fish. Overall, the present results point out a potential risk for human health from the consumption of deep-sea fish. In particular, for both, the red shrimp Aristeus antennatus, which is one of the most valuable fishing resources of the Mediterranean, as well as the commercially exploited fish Mora moro, THg levels considerably exceeded the recommended 0.5μg/g w.w. limit and should be consumed with caution.
一些研究发现,在世界各大洋的深海生物体内都存在高水平的汞(Hg),但由于人们对海洋中 Hg 的来源和循环尚未达成共识,其潜在成因尚不清楚。最近的研究结果表明,Hg 积累量可能随饵料深度的增加而增加,并指出深水区可能是海洋生物体内大部分 Hg 的来源,尤其是其有机甲基汞(MeHg)形式。在本研究中,我们测定了 12 种深海鱼类和一种十足目甲壳动物的总汞(THg)水平,并研究了其与物种氮稳定同位素比值(δ(15)N)的关系,δ(15)N 作为其营养级、平均体重和栖息地深度的指标。THg 水平范围为 0.27-4.42μg/g w.w.,除了一种物种之外,所有物种均超过了推荐的 0.5μg/g w.w. 指导值。尽管 THg 水平与 δ(15)N 值呈很强的相关性,与体重的相关性次之,但栖息地深度(以物种最大丰度的深度(DMA)来表示)对 Hg 积累也有显著影响。栖息范围较浅的鱼类物种的 THg 值低于根据其营养级(δ(15)N)和体重预测的值,而深水域鱼类的实测 THg 值则高于预测值。总体而言,本研究结果表明,食用深海鱼类可能会对人类健康造成潜在风险。特别是对于地中海最有价值的捕捞资源之一的红虾(Aristeus antennatus)和商业上可捕捞的鱼类(Mora moro),其 THg 水平明显超过了推荐的 0.5μg/g w.w. 限量,应谨慎食用。