Please read the entire article to see why this is a non-issue. Can't access the paper to determine just how old the "children" are in this study, but given that you absorb only 1 mg of nicotine from breathing in smoke of a 12mg-nicotine cigarette[0], I'd again treat nicotine poisoning as something not relevant to smoking in the real world.
[0] - http://www.electroniccigaretteconsumerreviews.com/how-much-n...