Key Findings:
- A new study from the Barcelona Institute for Global Health (ISGlobal) found that children exposed to second-hand smoke are more likely to show DNA methylation changes that may influence future disease risk.
- Researchers identified 11 DNA regions associated with second-hand smoke exposure, six of which are linked to diseases like asthma and cancer.
- These findings highlight the need for stronger measures to reduce childhood exposure to tobacco smoke, particularly in home environments.
A study published in Environment International reveals that second-hand smoke exposure during childhood leaves a lasting impact on DNA methylation — an epigenetic mechanism that alters how genes are expressed. Researchers analyzed blood samples from 2,695 children across eight European countries, linking DNA changes to the number of smokers in the household.
The study identified 11 regions of altered DNA methylation, with six linked to diseases for which smoking is a known risk factor. These epigenetic changes resemble those seen in individuals exposed to tobacco in utero or through active smoking.
The findings reinforce the importance of reducing children’s exposure to second-hand smoke, especially in home environments. Researchers emphasize that this is not solely an issue of individual responsibility but a broader public health concern that demands systemic change.
Source:
Cosin-Tomas, M., et al. (2025). Association of exposure to second-hand smoke during childhood with blood DNA methylation. Environment International, 195, 109204. https://doi.org/10.1016/j.envint.2024.109204