DATA IN NICOTINE, TAR, AND CO, BY BRAND. For L&M brand, light vs full strength, respectively (values per cigarette): mg nicotine 0.7, 0.9; mg tar 10-12, 14-15; mg CO 12-15, 14-16. No big reductions in the light version, and no better for the health. Note that absolute nicotine per cigarette is not the same as brain levels, which get enhanced by additives.
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