Air pollution has risen above an acceptable level.

空气污染已经超标。

《牛津词典》

Air pollution in the city had reached four times the acceptable levels.

这座城市的空气污染程度曾高达可接受标准的四倍。

《牛津词典》

Cases of breathing difficulties increase in lockstep with air pollution.

呼吸困难的病例随空气污染的加剧而增加。

《牛津词典》

But Mister Zundt says reducing air pollution and acid rain will reduce respiratory illnesses for people in the city.

VOA: special.2009.09.07

More than three billion people are at risk from indoor air pollution because of the heating or cooking fuels they use.

VOA: special.2010.02.01

The group's recent "State of the Air" report said Pittsburgh has the worst short-term fine particle pollution in the country.

VOA: special.2009.07.13

The debate over air pollution and, more specifically, the regulation of air pollution, raged on this week as the Environmental Protection Agency (EPA) watered down its cross-state pollution rule and House Republicans moved to delay new rules on toxic air pollution from cement plants, solid waste incinerators, and industrial boilers.

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"I guess it's a question of water pollution or air pollution, " he said.

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But research is continuing to pile up in support of the claim that not only are current air pollution regulations inadequate, but that air pollution is very much a public health issue.

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