Study Shows Toxic PAH Air Pollution Leads to Genetic Changes and Asthma -- Starting in the Womb
© 2012 Health Realizations, Inc.
Women who live in heavy traffic areas such as the Northern Manhattan and South Bronx areas of New York City could give birth to children with an increased risk of asthma due to what are called toxic PAH’s (Polycyclic Aromatic Hydrocarbons).
Children born to mothers who lived near heavy traffic areas while pregnant may have an increased risk of asthma.
The finding came from a study of the umbilical cord blood from New York City children, in which researchers found a change in a gene (called ACSL3) associated with prenatal exposure to polycyclic aromatic hydrocarbons.
Most commonly, PAHs are released into the air when fossil fuels, gasoline and garbage are burned, and as such perhaps the most common route of exposure to these chemicals is by breathing contaminated air. PAHs exist in cigarette smoke, wood smoke, vehicle exhaust, diesel exhaust and asphalt roads, as well as in the air of industrial coking, coal-tar and asphalt production facilities, along with trash-incinerating facilities.
Because of this, air in urban areas may have PAH levels 10 times higher than those in rural areas.
While exposure to PAHs has previously been linked to cancer, childhood asthma, cataracts, kidney and liver damage and other diseases, the new study found the chemicals result in epigenetic changes that may disrupt the normal functioning of genes by altering their expression.
"Our data support the concept that environmental exposures can interact with genes during key developmental periods to trigger disease onset later in life, and that tissues are being reprogrammed to become abnormal later," Shuk-mei Ho, University of Cincinnati researcher and lead author of the study, told LiveScience.com.
Where Else Can You be Exposed to PAHs?
PAHs are not only found in heavy traffic areas, they are also created when meats are barbecued, smoked or charbroiled. Other foods, including roasted coffee, roasted peanuts, refined vegetable oils and any food grown in PAH-contaminated soil (such as near a hazardous waste site) may also contain the chemicals, as can processed and pickled foods.
PAHs are also created when meats are barbecued, smoked or charbroiled.
Polycyclic Aromatic Hydrocarbons can also contaminate soil and water supplies, and certain areas in the United States have shown low-level PAHs in their water. The compounds are so widespread that simply coming into contact with air, water or soil around a hazardous waste site can increase your exposure.
Finally, PAHs are used in certain cosmetics, shampoos and hair dyes (anything that contains coal tar), and you may absorb some of the chemicals if you use these products. They're also present in certain household products, including creosote-treated wood and mothballs.
PAHs are Only One Risky Component of Air Pollution
Two out of every five people, or 42 percent of the U.S. population, live in counties that have unhealthful levels of ozone or particle pollution -- two types of air pollution -- according to the American Lung Association's State of the Air 2008.
In the most polluted cities it has been estimated that lives are shortened by an average of one to two years, according to research by the American Cancer Society and Harvard University, due to this pollution.
For instance, long-term exposure to air pollution, particularly that from motor traffic, increases the risk of fatal heart attacks, according to a study published by the Karolinska Institute, Institute of Environmental Medicine. Air pollution also increases the risk of heart attacks and strokes, and makes respiratory problems worse, by thickening the blood and increasing inflammation, respectively.
How can you protect yourself and your family from PAHs and other air pollution concerns?
If you are pregnant and live in a high-traffic area, you should follow commonsense guidelines to minimize your exposure to pollutants, such as:
To reduce your exposure to PAHs, specifically:
By keeping dust to a minimum, and taking a proactive stance regarding filtering your home’s indoor air, you can breathe freely and have peace of mind when it comes to your home’s air quality.