科学美国人60秒:Shark Fins Contain Toxic "One–Two Punch"

Living at the top of the food chain, sharks can accumulate dangerous levels of methylmercury. So much that pregnant women and children are advised not to eat shark at all. But sharks can accumulate another toxin too, called BMAA, which has been linked to the development of neurodegenerative disease. Which could be bad news for shark eaters.
鲨鱼生活在食物链的顶端, 可以积聚汞. 所以,建议孕妇和儿童不要吃鲨鱼.但是鲨鱼还能积累另外一种毒素,BMAA,这种毒素与神经退行性疾病形成有关.这对爱吃鲨鱼的人而言,是个坏消息.
"Mercury in combination with BMAA is a one-two punch." Deborah Mash, a professor of neurology at the University of Miami's Miller School of Medicine. "These are two synergistic toxins. So even if there are low levels of exposure from the mercury or the BMAA, when humans are exposed to both of these toxins, then they will have a synergistic effect on the nervous system."
汞和BMAA结合可谓是”强强联手. Deborah Mash是迈阿密大学米勒医学院的神经学教授.它们是两个协同的毒素.所以即使汞或者BMAA的含量很低,但是只要人类接触到这两种毒素,它们就会对人的神经系统产生协同效应.
BMAA starts out in cyanobacteria, and travels up the food chain through crabs and shrimp and fish. And, as previous studies have shown, all the way to sharks. What Mash and her colleagues wanted to know was how widespread the problem was, and if the chemical often appeared alongside mercury. So they analyzed fin and muscle samples from 10 species of shark—55 individuals in all—from the Atlantic and Pacific Oceans. And they found BMAA and mercury in all 10 species. Suggesting that exposure to that "one-two punch" could be pretty common. The results are in the journal Toxins.
BMAA最初存在于蓝藻中, 之后,通过螃蟹、虾类和鱼类进入食物链。就如之前的研究显示的，最后所有的渠道都通向了鲨鱼。Mash和她的同事们想要知道，如果化学物质中，经查出现汞，此问题的普遍性。所以，他们分析了太平洋和大西洋中10种鲨鱼(共有55种)的鳍和肌肉样本。在这10种鲨鱼中，均发现了BMAA和汞。这表明，这两种毒素结合非常的普遍。该研究结果发表在《毒素》杂志上。
It's still not clear at this point what sort of risk this occasional exposure through food might have. Still, Mash isn't waiting.
现在尚不清楚，通过食物这些毒素会产生何种影响。但是Mash并没有坐等结果。
"I myself would not want to be exposed to BMAA or methyl mercury in my diet by eating shark fin or shark meat or taking shark cartilage products. We already know that mercury is toxic to our health. And we already know that BMAA plus mercury is a very bad mix for the brain. So people need to be concerned, and I think that's not only for the benefit of us as consumers, but also to the poor sharks, who are threatened with extinction."
我一般不会接触BMAA或甲基汞，因为我不吃鲨鱼肉、鲨鱼鳍或者其他的鲨鱼软骨产品。我们已经知道汞危害人类健康。同时BMAA和汞结合危害人类大脑。所以，我认为人类应该担忧，不仅仅是为了我们人类的福祉，同时也是为了濒临灭绝的可怜的鲨鱼
Conservationists have argued for years that sharks should be spared. Maybe now that it's us who are threatened... people might finally start to leave them alone.
多年来，环保人士一直认为，应该保护鲨鱼。现在，或许受到威胁的是我们人类…所以，现在，人类还是担心一下自己吧~