Children exposed to second-hand smoke exhibit critical DNA changes that may affect their susceptibility to diseases in adulthood, according to a new study by the Barcelona Institute for Global Health.
Children exposed to second-hand smoke at home are at a higher risk of experiencing changes in their DNA, according to a recent study led by the Barcelona Institute for Global Health (ISGlobal), a center supported by the “la Caixa” Foundation. The findings, published in Environment International, emphasize the critical need to reduce children’s exposure to second-hand smoke.
The researchers analyzed data from 2,695 children aged 7-10 from eight European countries — Spain, France, Greece, Lithuania, Norway, the Netherlands, the UK and Sweden. They examined blood samples to identify DNA methylation changes, a key epigenetic mechanism, which were correlated with the number of smokers in each household.
The study found DNA methylation changes in 11 regions, some of which are known to be linked to diseases commonly associated with smoking, such as asthma and cancer. Additionally, these changes mirror those seen in direct smokers or children exposed to maternal smoking during pregnancy.
“Our study shows that second-hand smoke during childhood leaves its mark at the molecular level and can alter the expression of genes that influence disease susceptibility in adulthood,” first author Marta Cosin-Tomàs, an ISGlobal researcher, said in a news release.
Despite more stringent regulations on smoking in public areas, homes remain a significant source of second-hand smoke for children.
In 2004, approximately 40% of children globally were estimated to be exposed to tobacco smoke. This exposure is not only linked to an increased risk of respiratory and cardiovascular diseases but can also impact neurological development and immune function.
“The results suggest that second-hand smoke in childhood leads to epigenetic changes similar to those observed with intrauterine exposure to tobacco or active smoking. This underlines the urgency of implementing comprehensive measures to reduce childhood exposure to tobacco smoke, both at home and indoors,” added senior author Mariona Bustamante, an ISGlobal researcher.
Cosin-Tomàs further argued that the issue extends beyond individual family responsibility to a broader public health challenge.
“It is not a question of appealing to the individual responsibility of families: exposure to tobacco is a public health problem and hides an issue of social inequality,” she concluded. “Socio-economic and environmental factors, together with the influence of powerful commercial interests, make it difficult to reduce exposure to second-hand smoke in certain households.”
This groundbreaking research underscores the need for more stringent regulations and public health interventions to protect children from the detrimental effects of second-hand smoke. As society takes steps to limit smoking in public spaces, it is crucial to extend these protections to private environments where children are most vulnerable.