Smoking and Baby Poop

Telltale metabolites in meconium.

Attention pregnant smokers: You can run, but you can’t hide. A chemical analysis of your baby’s first official poop can establish whether your infant has suffered from prenatal exposure to tobacco smoke. The higher the levels of tobacco metabolites, the more likely the mother was an active smoker.

The authors of a study published in Environmental Health found that nicotine and assorted tobacco metabolites were easily detectable in an infant’s meconium, the black, tar-like substance that comprises the first stools from newborns. In a study of 337 babies, tobacco metabolite concentrations were higher in active smokers than in non-smoking women exposed to second-hand smoke only.

The researchers say the meconium method is not superior to other methods of measurements, but suggest it may be a useful adjunct in estimating “gestational exposure to other environmental toxicants that exhibit more variability during pregnancy, especially non-persistent compounds like bisphenol A and phthalates.”

One striking aspect of the study is that the researchers found nicotine and cotinine—a common nicotine metabolite--in most of the meconium samples analyzed. 80% of the samples contained nicotine. So it is not a question of exposure, it’s a question of the degree of exposure. Should we be concerned about the lower levels of exposure registered from second-hand smoke? Apparently so, since “meconium tobacco smoke metabolites were inversely associated with birth weight,” according to Joe M. Braun and coworkers. Braun suggested that additional biomarkers for tobacco exposure were important, based on his belief that tobacco smoke exposure during pregnancy is under-reported.

This looks like a potentially useful tool for epidemiological studies that enroll women and infants at birth. More studies of this kind are needed, because prenatal tobacco smoke exposure is increasingly implicated in “adverse infant and childhood health outcomes.”

Graphics Credit: http://www.youquittwoquit.com/