levels are still significantly higher in e-cigarette smokers than non-smokers, the authors of the new study point out.
The mothers of the babies with NNAL
in their urine smoked an average of 76 cigarettes per week.
Prof Milunsky's findings - published in the journal Prenatal Diagnosis - discovered NNAL
in the amniotic fluid of 52 per cent of women smokers and seven per cent of non-smokers.
Exposing a foetus to the carcinogen called NNAL
may be the first stage of a 'double hit', making it more susceptible to the disease in later life.
New tests picked up traces of the cancer-causing chemical NNAL
, found in tobacco smoke, in the wombs of pregnant women.
Of the 31 infants whose mothers smoked during pregnancy, 22 had NNK metabolites called NNAL
-Gluc in their urine.
The authors concluded that the uptake of TSNAs in humans, measured by levels of the biomarker NNAL
, was roughly the same for Ariva[R] and Stonewall[R] as the uptake level for the nicotine replacement lozenge that was studied.
The use of biomarkers could reduce measurement error; however, to our knowledge, no published studies have evaluated the association between exposure to SHS and childhood obesity using cotinine or NNAL
to characterize exposure to SHS.
The researchers analyzed urine samples from each smoker, homing in on two breakdown products of NNK: NNAL
In commenting on the NNAL
levels among subjects using Ariva[R], the authors noted, "Interestingly, total NNAL
levels in subjects who used Ariva, although higher, were not significantly different from those in subjects who used the medicinal nicotine lozenge.
Levels of NNAL
(4-(methylnitrosamnino)-1-(3-pyridyl)-1-butanol) in the blood can therefore predict lung cancer risk in rodents as well as in humans.
One in two children examined - all under a year old - had traces of NNAL
, a substance produced only by cigarette fumes.