It appears that the butter was contaminated by the PBDE from its paper wrapping, but how the chemical got into the packaging is a mystery-and of great concern.

看上去这些奶油是被它的纸质包装上的PBDE污染的，但是这些化学物质是怎么进入到包装内部却不得而知——但已经足以让人担忧。

youdao

The producer of the suspect formula, the Sanlu Group, recalled 700 tons of its formula after determining on Thursday that it had been contaminated with melamine, an industrial chemical.

嫌疑奶粉的生产商——三鹿集团，在周四宣布其奶粉成分被一种工业化学物质三聚氰胺污染后，已经取消了700吨的订货。

youdao

Now, dozens of people, many clutching infants, queue in the hot sun outside to return powder that could be contaminated with a potentially lethal chemical.

现在，几十人在门外的骄阳下排队退回也许受到可能致命的化学成分污染的奶粉，许多人手里抱着婴儿。

youdao

She says when state regulators tested imported shrimp they found it was contaminated with antibiotics and other chemical residues that are illegal in the U.S.

VOA: standard.2010.05.27

But HyQ could also take on inspection tasks in contaminated environments like nuclear power stations or chemical factories.

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