AIR POLLUTION

For a pregnant woman, perhaps the city is not the best place to be.
A new National Institutes of Health study shows the polluted air in the inner city is definitely affecting unborn babies, causing DNA damage while they are still in the womb. Previous studies done on rats have shown that upon exposure to certain pollutants, the type commonly found in the air of inner cities, the fetus is more susceptible to the cancer causing effects than the adult rat.

New research shows that inner city air pollution can definitely affect unborn babies, causing DNA damage while they are still in the womb. For a pregnant woman, perhaps the city is not the best place to be.

Previous studies done on rats have shown that upon exposure to certain pollutants, the type commonly found in the air of inner cities, the fetus is more susceptible to the cancer causing effects than the adult rat. A National Institutes of Health study now confirms unborn human fetuses are at a similar risk.

The research, done at Columbia University, New York, shows babies in the womb are more susceptible than are their mothers to DNA damage from the effects of common pollutants put out by cars and industry. The study was designed to measure the effects of prenatal and maternal exposure to combustion related pollutants, such as car and truck emissions, residential heating, and power plants.

Researchers collected data from 265 pairs of mothers and newborns living in New York City. Blood samples were taken from the mother and from the umbilical cord blood at the time of birth…blood that comes from the baby. The researchers looked for protein complexes formed when a pollutant binds to the DNA.

DR. Frederica Perera, the lead investigator at the Mailman School of Public Health, says,
“This study shows that the level of DNA damage is higher, much higher in babies in the womb than we had previously expected.” This is in spite of the fact there was a ten fold lower dose of pollutants that got to the baby because of the protection provided by the placenta.

“Yet the levels of DNA damage were similar were comparable in mothers and their babies and this evidence that the fetus is particularly sensitive to this kind of damage is of concern because DNA damage has been linked to increased risk of cancer and of developmental growth and developmental problems,” says Dr. Perera.

The researchers also measured the presence of a chemical called cotinine, which is produced as a breakdown product of nicotine. The cotinine level indicates exposure to second hand smoke, and thus a cancer risk.

“The findings really underscore the importance of reducing air pollution levels and air pollution control in our city. These results have broad relevance to metropolitan areas throughout the country and the world in fact,” says Dr. Perera.

Dr. Perera says this is a warning to public health officials that air pollutants have a very real risk to unborn babies who are exquisitely sensitive. Still, for those who love to be city dwellers, it’s a tough concept to swallow. One pregnant woman who did not want to be identified said, “I’m not sure if the pollution will have an effect on my baby. Unfortunately it’s unavoidable.”