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The Conversation USA

How California’s war on smog and its ambitious car pollution rules made everyone’s air cleaner

  • Written by Ann E. Carlson, Professor of Environmental Law, University of California, Los Angeles
imageBefore catalytic converters, starting a gas-powered vehicle could choke the surrounding area with smog.Bettmann via Getty Images

Cars on the road today are 99% cleaner than they were in 1970. Air quality in the United States is much, much better as a result. In Los Angeles, where I live, lead levels in the air were 50 times higher in the 1970s than...

Read more: How California’s war on smog and its ambitious car pollution rules made everyone’s air cleaner

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