As you suggested, the fish contains a toxic substance.

正如你提出过的那鱼含有毒性物质。

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Automobile exhaust tetraethyl lead is a highly toxic substance.

汽车尾气中的四乙基铅是剧毒物质。

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Bisphenol a, a common compound found in many plastics, has been listed as a toxic substance in Canada but is still deemed safe in the U.S..

双酚a，在许多塑料产品中常用的一种物质，现在已经被加拿大写在有毒物质的清单上了，但是，在美国，它仍然被认为是安全的。

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This can turn a non-toxic substance called 5-fluorocytosine into a nasty chemical called 5-fluorouracil that kills all cells, normal and malignant.

ECONOMIST: Cancer treatment

The American Medical Association, the American Public Health Association and the American Nurses Association have previously called for changes in the Toxic Substance Control Act.

CNN: Pediatricians urge tougher chemical safety law

Where companies need to be careful in dealing with both compliance and innovation, Kirschner cautions, is when substituting a known toxic substance with an alternative.

FORBES: How International Regulations Are Changing American Supply Chains