Portland has made incremental advances in reducing its sewage overflows since the Clean Water Act went into effect more than 20 years ago.

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Train, who was the EPA administrator when the Clean Air Act went into effect, overrode objections from industry in order to regulate lead emissions from automobiles in the 1970s.

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"The side-effect profile looks amazingly clean, " says Jeffrey A. Lieberman , vice chair of psychiatry at the University of North Carolina in Chapel Hill Medical School.

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