Fetal growth and length of gestation in relation to prenatal exposure to environmental tobacco smoke assessed by hair nicotine concentration.

Abstract

We assessed the effects of prenatal exposure to environmental tobacco smoke on fetal growth and length of gestation. The study population consisted of 389 nonsmoking women who were selected from a population-based study in southeast Finland on the basis of questionnaire information after delivery (response rate 94%). The final exposure assessment was based on nicotine concentration of maternal hair sampled after the delivery, which measures exposure during the past 2 months (i.e., the third trimester). The exposure categories were defined a priori as high (nicotine concentration [Greater and equal to] 4.00 microg/g; n = 52), medium (0.75 to < 4.00 microg/g; n = 186), and low as the reference category (< 0.75 microg/g; n = 151). In logistic regression analysis, controlling for confounding, the risk of preterm delivery (< 37 weeks) was higher in the high [adjusted odds ratio (OR) = 6.12; 95% confidence interval (CI), 1.31-28.7] and medium exposure categories (adjusted OR = 1.30; 95% CI, 0.30-5.58) compared with the reference category, and there was a 1.22 (95% CI, 1.07-1.39) increase in adjusted OR with a 1 microg/g increase in hair nicotine concentration. The corresponding adjusted OR was 1.06 (95% CI, 0.96-1.17) for low birth weight and 1.04 (95% CI, 0.92-1.19) for small-for-gestational-age.

Transgenerational Exposure to Environmental Tobacco Smoke

“…Similar to this study, many others reported a significant association between SHS and premature birth [12,13,14,15,16]. …”

Protecting Children from Environmental Toxins

“…Indeed, there is compelling evidence from epidemiologic studies of widespread contaminants such as lead, tobacco, and PCBs that human studies are essential to ensure that children are not harmed by low levels of exposure [11,12,13,14,15,16,17,18,19,20,21,22, 23,24,25,26,27,28,29,30,31,32,33,34,35, 36,37,38,39,40]. …”

“…Over the past three decades, researchers have found that remarkably low-level exposures to these toxins are linked with less overt symptoms of toxicity—intellectual impairments, behavioral problems, spontaneous abortions, or preterm births [6,7,8,9,10,11,12,13,14, 15,16,17,18,19,20,21,22,23,24,25,26,27, 28,29,30,31,32,33,34,35,36,37,38,39,40]. Moreover, there is emerging evidence that decrements in intellectual abilities and low birth weight linked with lead or tobacco are, for a given increment of exposure, greater at lower levels than those found at higher levels [10,41,42,43].…”

Human Health Risks from Low-Level Environmental Exposures: No Apparent Safety Thresholds

“…In a Finnish study of nonsmoking women, the risk of preterm birth was dose-related to self-reported prenatal maternal ETS exposure intensity and maternal hair nicotine levels [13]. Glutathione-S-transferase (GST) enzymes detoxify many chemicals, including polycyclic aromatic hydrocarbons and certain other toxicants present in tobacco smoke.…”