Findings of a recent study carried out by a team of Australian, British and Sri Lankan researchers that was published in the European Respiratory Journal indicate increased evidence that secondhand smoking holds effects on health for two generations.

One of the co-authors, Jiacheng Liu from Melbourne University, stated, “We found that the risk of non-allergic asthma in children increases by 59% if their fathers were exposed to secondhand smoke in childhood, compared to children whose fathers were not exposed." adding that the risk reaches 72% if the father was a smoker as well.

The health and policy manager at Ashma + Lung UK, Jon Foster, commented on the findings,“This research is truly shocking. The fact that children born today have a 59% increased risk of developing asthma if their father was exposed to passive smoking as a child shows the huge impact smoking has on other people’s health.”

Intergenerational risk

The head of the European Respiratory Society's tobacco control committee, Prof. Jonathan Grigg, stated that the findings increase evidence that the risk of smoking is intergenerational, and that more actions must be taken to protect children from the harms of smoking, urging to increase the stop smoking services and NHS measures to help adults to quit smoking.

Dr. Dinh Bui, another co-author of the study, said that “Our findings show how the damage caused by smoking can have an impact not only on smokers but also their children and grandchildren.” Dr. Bui explained,“Epigenetic changes can be caused by environmental exposures such as smoking, and they may be inheritable to next generations. Specifically, when a boy is exposed to tobacco smoke, it may cause epigenetic changes to his germ cells. These are the cells that go [on] to produce sperm." stating that the genetic changes will be inherited by the children, increasing the risk of developing asthma.

Smoke exposure before the age of 15 years is a major risk factor

The research that was conducted based on analyzing the data of 1,689 pairs of fathers and their children, added that "Findings suggest that when boys are passively exposed to their parents’ tobacco smoke before the age of 15 years, their offspring have increased risk of non-allergic childhood asthma, but not allergic asthma."