过度捕捞的很多海洋物种中，有许多含有高浓度的汞和多氯联苯。

Many Marine species are overfished, and some have high levels of mercury and PCBs.

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多氯联苯和六氯苯都是长期存在，并积累在食物链中的污染物，取缔这些物质需要长达数十年的时间。

PCBs and HCB are both long-lived pollutants that accumulate in food chains and take decades to break down.

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事实上，研究表明超过95%的12岁以上的美国人血液中仍然检测出含有多氯联苯。

In fact, studies have shown that more than 95 percent of Americans older than 12 still have detectable levels of PCBs in their blood.

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