The quantity of chemical pollutants has increased exponentially.

化学污染物的数量已经急剧上升。

《柯林斯英汉双解大词典》

In a word, marine sediments has become the main reservoir of persistent and poison chemical pollutants in marine environment.

海洋沉积物已经成为海洋水体环境中持久性的、有毒的化学污染物的主要存贮地。

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Thompson's rigorous quality control procedures test all raw materials to ensure no chemical pollutants such as PCBs, mercury and lead.

汤普森的严格的质量控制程序测试所有原材料，以确保没有化学污染物，如多氯联苯，汞和铅。

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Chockablock with heavy metals, chemical waste, air pollutants and, in the case of infamous Chernobyl, Ukraine, deadly radiation, these are the worst industrial cesspools on earth--and they rarely make headlines.

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The plastic also acts as a chemical sponge absorbing some of the worst pollutants in the sea and increasing its toxicity when swallowed.

CNN: Fighting the tide of plastic bags in a world awash with waste

Putting the cart before the horse, the EPA issued preliminary clean up goals for dioxin on December 31, 2009 before the agency had completed a new risk assessment on the chemical, widely perceived as one of most toxic environmental pollutants (the assessment is due by the end of this year).

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