A study revealed that exposure to unclean cooking fuels during pregnancy and early childhood is linked to developmental delays in children.
The negative health effects of secondhand smoke on infants are widely recognized. A study by the University at Buffalo explored a similar question: could common cooking fuels like natural gas, propane, and wood pose comparable health risks when used indoors, especially for young children?
This analysis involving 4,735 mother-child pairs from the Upstate KIDS Study investigated the link between indoor air pollution and child development. This large-scale study followed participants from pregnancy to age three, monitoring developmental milestones. Indoor air pollution data was self-reported during pregnancy and after birth.
The research, led by Alexandra Grippo, highlights that while the dangers of cigarette smoke during pregnancy are well-established, the potential risks of cooking fuels may be overlooked. Grippo emphasizes that gas stoves, frequently used in homes, contribute significantly to indoor air pollution through carbon monoxide and nitrogen dioxide emissions. This is particularly concerning for infants and young children who spend more time indoors and have underdeveloped respiratory systems, making them more vulnerable to pollutants.
The study defines clean fuel use as electricity for cooking (including microwaves) and electric or solar-powered heating. Conversely, unclean fuel users were those who relied on fuels other than electricity. While recent regulations in some cities aim to restrict gas stoves in new buildings due to safety concerns, the research team underscores that their findings extend beyond just natural gas.
Co-first author Kexin Zhu emphasizes the increased risk of developmental delays observed in children exposed to any type of unclean cooking fuel. However, due to limited sample size, the study could not delve deeper into the effects of specific fuels. Zhu acknowledges the need for further research with larger sample sizes to explore the specific relationship between gas stove usage and child development.
Study results
Exposure assessment involved collecting information on children’s exposure to cooking fuels, heating fuels, and secondhand smoke at 4 months, 1 year, and 3 years old. Parents reported the usual cooking and heating fuels used, and whether anyone in the household smoked.
The Ages and Stages Questionnaire, a standardized tool used to screen development, was employed to measure children’s progress in five key domains: communication, gross and fine motor skills, social skills, and problem-solving. It is believed to be the first U.S. study to examine the combined effects of cooking fuels, heating fuels, and secondhand smoke on these developmental domains, according to Dr. Lina Mu, senior author and an epidemiology and environmental health professor.
The study revealed a concerning association. Unclean cooking fuel exposure during pregnancy and early childhood (up to 36 months) increased the risk of developmental delays across all domains, with a particularly significant impact on gross motor skills (52% higher odds) and social skills (36% higher odds).
Interestingly, researchers observed stronger associations between unclean cooking fuel and developmental delays in specific groups, including infants of young mothers, single births (singletons), and male infants. The study did not find the same association for infants of older mothers, multiple births (non-singletons), or female infants.
Passive smoke exposure was also a concern, with 21.5% of women reporting exposure during pregnancy and 14.2% admitting to smoking themselves. Notably, passive smoke exposure was linked to problems in the problem-solving domain even among children of non-smoking mothers, highlighting the potential for secondhand smoke to negatively impact development.
These findings underscore the importance of minimizing indoor air pollution exposure, not just from secondhand smoke but also from cooking fuels. Further research is needed to explore the specific effects of different fuel types.
The study highlights the presence of toxicants like lead in secondhand smoke, known to hinder children’s development, as noted by co-author Kexin Zhu.
An observed association linked passive smoke exposure with increased odds of failing the problem-solving domain even in children of non-smoking mothers. This emphasizes the importance of shielding children from secondhand smoke to safeguard their health and development.
https://www.sciencedirect.com/science/article/abs/pii/S0013935123013324
Abstract
Limited human studies have investigated the impact of indoor air pollution on early childhood neurodevelopment among the US population. We aimed to examine the associations between prenatal and postnatal indoor air pollution exposure and early childhood development in a population-based birth cohort.
This analysis included 4735 mother-child pairs enrolled between 2008 and 2010 in the Upstate KIDS Study. Indoor air pollution exposure from cooking fuels, heating fuels, and passive smoke during pregnancy, and at 12 and 36 months after birth were assessed by questionnaires. Five domains of child development were assessed by the Ages and Stages Questionnaire at 4, 8, 12, 18, 24, 30, and 36 months. Generalized estimating equations were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for potential confounders.
Exposure to unclean cooking fuels (natural gas, propane, or wood) throughout the study period was associated with increased odds of failing any development domain (OR = 1.28, 95% CI 1.07, 1.53), the gross motor domain (OR = 1.52, 95% CI: 1.09, 2.13), and the personal-social domain (OR = 1.36, 95% CI: 1.00, 1.85), respectively. Passive smoke exposure throughout the study period increased the odds of failing the problem-solving domain by 71% (OR = 1.71, 95% CI 1.01, 2.91) among children of non-smoking mothers. No association was found between heating fuel use and failing any or specific domains.
Unclean cooking fuel use and passive smoke exposure during pregnancy and early life were associated with developmental delays in this large prospective birth cohort.