http://www.pnas.org/cgi/content/full/97/23/12493
2'-Hydroxylation of nicotine by cytochrome P450 2A6 and human liver microsomes: Formation of a lung carcinogen precursor
Thats what would make smoking while pregnant dangerous to a fetus.
"Our results are potentially significant because aminoketone is the direct precursor to the tobacco-specific lung carcinogen NNK, which is believed to play a significant role as a cause of lung cancer in smokers"
They don't know if NNK is an ACTUAL cause of lung cancer.
Their 'experiments' are based on the assumption that it is.
Proves nothing.
There you go again.
EXPECTING HARD, SOLID FACTS to blunt the DENIAL SO CHRONICALLY FLOODING smoking threads.
DENIAL and selfishness and rebellion.
All pretending to be intellectually defensible, freedom-loving; modern; with-it; kosher; warranted; advisable; wonderful; life-enhancing.
Sheesh.