does chewing tobacco lower sperm count Prevalence of abnormal spermatozoa in sub-fertile males Effects of marijuana and tobacco
Description
Family aggregation related to lung cancer is likely multifactorial, including exposure to secondhand smoke, major genetic factors (e.g., chromosome 6p locus, CYP1A1 gene), other genes that modify risk of lung cancer, and genes that may enhance nicotine addiction or modify nicotine metabolism (DAmico, 2008

doi:10.1542/peds.2005-0141 14

Smoking likewise may make nourishment less scrumptious for a few smokers, further controling hunger

Could this be a hidden reproductive crisis
