Tabakspezifische transplazentare kanzerogene, nikotin und cotinin im urin yon neugeborenen rauchender mutter

Background: Cigarette smoking is common during pregnancy and can expose the developing fetus to transplacental carcinogens, but relatively little information is available on fetal uptake of such compounds. It was the aim of the present study to analyze the first urine of newborns of mothers who did or did not smoke for metabolites of the tobacco-specific carcinogen 4- (methylnitrosamino)-1-(3-pyridyl)-l-butanone (NNK) as well as nicotine and cotinine. Methods: First urine of newborns was collected and analyzed for two metabolites of NNK. The metabolites are 4-(methylnitrosamino)-1-(3-pyridyl)- 1-butanol (NNAL) and its glucuronide, NNAL-Gluc. The analyses were carried out by gas chromatography and nitrosamine-selective detection with confirmation by mass spectrometry. Nicotine and cotinine were analyzed by gas chromatography-mass spectrometry. Results: NNAL-Gluc was detected in 22 of 31 (71%) of the urine samples from newborns of smoking mothers; in 4 cases, NNAL was also detected. Neither of these analytes was detected in the 17 samples from newborns of mothers who did not smoke. NNAL plus NNAL-Gluc levels in the positive quantified newborn urine samples were 0.19±0.14 pmol/ml urine, about 10% of that seen in adult smokers. NNAL plus NNAL-Gluc levels correlated with the number of cigarettes smoked per day during pregnancy (r=0.55; p<0.005). Nicotine and cotinine levels in the urine of newborns of smoking mothers were also significantly higher than in the urine of newborns of non-smoking mothers and correlated well with levels of NNAL plus NNAL- Gluc. Conclusions: The results demonstrate that two metabolites of the tobacco-specific transplacental carcinogen NNK are present in the urine of newborns born to mothers who smoke cigarettes.