When the chemicals react with nitrogen oxide--found in pollution from cars--they form ozone, a much bigger health threat to humans and animals.

然后，当这些化学物质与氮氧化合物(存在于汽车排放的废气中)发生化学反应时，就会形成臭氧，这会对人类和动物的健康构成更大的威胁。

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"This legislation will reduce or eliminate some of those tariffs, which will significantly lower costs for American companies across the manufacturing landscape, from cars to chemicals, medical devices to sporting goods."

VOA: standard.2010.08.11