Twenty percent of China''s air pollution can be attributed to goods exported to America, with some of those emissions drifting back to the Western United States, finds a study published this week in the journal Proceedings of the National Academy of Sciences.Read more at http://news.mongabay.com/2014/0120-china-air-pollution-returns.html#E38vE2PX1YtfI2oT.99 Twenty percent of China´s air pollution can be attributed to goods exported to America, with some of those emissions drifting back to the Western United States, finds a study published this week in the journal Proceedings of the National Academy of Sciences.