如果，1美國的大氣質量明顯高於中國，2而吸煙人口又明顯低於中國，則為何肺癌同是首發，或前位高發癌？

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• for one, indoor air matters more -jaydad- ♂ (0 bytes) () 10/18/2013 postreply 13:49:46

• for two, carcinogenic foods are much stronger cancer-causing ove -jaydad- ♂ (158 bytes) () 10/18/2013 postreply 14:00:07

• over trace amount carcinogen in tobacco smoke -jaydad- ♂ (0 bytes) () 10/18/2013 postreply 14:02:06

• Thank you for the information, -大江川- ♂ (279 bytes) () 10/18/2013 postreply 14:28:40