她发现，许多家庭都暴露在高水平的、有时是致命的化学物质和其他有毒物质中，但她不被允许公开自己的信息。

She found many families were being exposed to high, sometimes deadly, levels of chemicals and other toxic substances, but she was not allowed to make her information public.

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首先，擦痕上的化学物质提供了动物的个体特征信息；没有两种哺乳动物会产生相同的气味。

First, the chemicals deposited on the rub provide information on the individual identity of an animal; no two mammals produce the same scent.

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信息素和 odorants （被检测为气味的化学物质）之间的区别可能是模糊的，一些研究人员将信息素归类为一种 odorant。

The distinction between pheromones and odorants—chemicals that are consciously detected as odors—can be blurry, and some researchers classify pheromones as a type of odorant.

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