How Worried Should I Be About Secondhand Smoke?

In an ongoing study by the Columbia Center for Children’s Environmental Health in Manhattan, more than 700 local pregnant women and their children are being monitored for the effects of air pollutants on their health. The study is led by Frederica Perera, Dr.P.H, who spoke with us about the impact of secondhand smoke during pregnancy, its health risks for young kids, and tips on avoiding it.

cigarette and smoke in carHow does secondhand smoke affect pregnant moms?

It affects their babies in a number of ways. First of all, maternal active smoking we know quite a lot about and the effects on birth outcomes and the subsequent cognitive development. We’ve also learned that mothers breathing other people’s tobacco smoke is a risk factor for these adverse birth outcomes—lower birth weight and development delays in children. There is evidence from our study in New York City that prenatal exposure to secondhand smoke in conjunction with air pollution in the city may be increasing the risk for asthma in children. People do understand the risks of active maternal smoking during pregnancy, but the risk from other people’s smoke is not so well understood.


What are the health risks for kids?

Environmental tobacco smoke is a mixture of more than 4,000 chemicals that adversely affects fetal growth as well as child growth and development. Adverse effects include deficits in birth weight, birth length, and cognitive functioning at age 3.


Are there any long-term effects seen in kids exposed to secondhand smoke?

There are a number of adverse effects associated with secondhand smoke exposure to the mother during pregnancy that manifest later in the children’s lives. This exposure is harmful to the developing baby, and steps should be taken to reduce or eliminate [it] during pregnancy and in childhood. We have been able to look at the continuum of effects over time in a cohort of pregnant mothers, [by] following their babies from delivery into adolescence. Secondhand smoke exposure in utero may be increasing the risk of cancer later on in those children—the link has been with lung cancer.


What levels of secondhand smoke are considered dangerous?

That depends on the individual. It is difficult to say that there is a safe level, that [there is a safe number of cigarettes]. That is impossible to identify for any individual.


How can pregnant moms and young children avoid secondhand smoke?

While there are restrictions on smoking in public places and restaurants and bars and outside hospitals and other public sites, the household exposure is very important. We suggest that family members who smoke make every effort to quit smoking or to take it outside and not to bring that smoke into the home. To ask people to not smoke in the presence of children and pregnant women is a reasonable thing to do.


Do you think there should be stricter regulations on smoking?

I’m not sure of the status of all the regulations in the country, but I know great strides have been made in NYC on removing smoking from public places and that is a definite step forward. People at all life stages are going to benefit from the reduction of smoking and hopefully the elimination of secondhand smoke.


Frederica Perera, Dr.P.H., is a professor at Columbia University’s Mailman School of Public Health and serves as director of the Columbia Center for Children’s Environmental Health. Dr. Perera earned her undergraduate degree from Harvard University and her master’s and doctoral degrees in public health from Columbia University.