The pollution came from attempts to recover the lead while recycling motor batteries on the black market.

这些污染是由于试图在黑市上再生利用起动机电池的铅而产生的。

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This, too, evolved in response to industrial pollution. It developed black wings, so that it was invisible when it settled on soot-covered tree trunks.

在遭受工业污染后，他们进化为黑色翅膀，甚至当他们栖息在煤烟覆盖的树干时以至于能够达到隐形效果。

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And cutting back on black carbon will also pay immediate health dividends, with less air pollution and fewer deaths from respiratory diseases.

减少炭黑排放还能带来健康的额外好处，因为空气污染少了，死于呼吸道疾病的人也少了。

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There is a length of one side of a 200-year-old arch turned black and porous with pollution.

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It has been claimed this could eliminate 20% of the capital's exhaust pollution caused by its 22, 000 black cabs.

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