在《人类环境杂志》上发表的一项研究称，科学家们发现，自引进无铅汽油以来，美国东北部土壤中的铅含量已经显著下降。
In a study published in the journal Ambio, scientists found that lead levels in soil in the North-eastern United States had decreased markedly since the introduction of unleaded gasoline.
马里兰州交美特科技公司的莫斯坎瑞斯，一位专门研究污染的科学家，说：“早在节能技术出现之前，室内环境就已经很脏了。”
"The indoor environment was dirty long before energy conservation came along," says Moschandreas, a pollution scientist at Geomet Technologies in Maryland.
他是一位研究如何减少垃圾的环境科学家，其中包括研究减少垃圾车行驶时掉下来的东西，当你考虑到这一点，自然就能明白他为什么会养成这种奇怪的习惯了。
His strange habit makes sense when you consider that he's an environmental scientist who studies how to reduce litter, including things that fall off garbage trucks as they drive down the road.
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