It’s no secret that smoking kills. According to the Centers for Disease Control and Prevention (CDC) smoking is responsible for around 480,000 deaths a year in the US, including more than 41,000 due to second hand smoke. Now a new study says that damage can begin in utero long before the child is born.

Previous studies had suggested that smoking could pose a serious risk to a fetus but those studies were done in petri dishes in the lab or using animals so the results were difficult to extrapolate to humans.

Researchers at the University of Edinburgh in Scotland got around that problem by using embryonic stem cells to explore how the chemicals in tobacco can affect the developing fetus. They used the embryonic stem cells to develop fetal liver tissue cells and then exposed those cells to a cocktail of chemicals known to be found in the developing fetus of mothers who smoke.

Dangerous cocktail

They found that this chemical cocktail proved far more potent, and damaged the liver far more, than individual chemicals. They also found it damaged the liver of males and females in different ways.  In males the chemicals caused scarring, in females it was more likely to negatively affect cell metabolism.

There are some 7,000 chemicals found in cigarette smoke including tar, carbon monoxide, hydrogen cyanide, ammonia, and radioactive compounds. Many of these are known to be harmful by themselves. This study highlights the even greater impact they have when combined.

Long term damage

The consequences of exposing a developing fetus to this toxic cocktail can be profound, including impaired growth, premature birth, hormonal imbalances, increased predisposition to metabolic syndrome, liver disease and even death.

The study is published in the Archives of Toxicology.

In a news release Dr. David Hay, one of the lead authors, said this result highlights yet again the dangers posed to the fetus by women smoking while pregnant or being exposed to secondhand smoke :

“Cigarette smoke is known to have damaging effects on the foetus, yet we lack appropriate tools to study this in a very detailed way. This new approach means that we now have sources of renewable tissue that will enable us to understand the cellular effect of cigarettes on the unborn foetus.”