The combustion and exhaust in cars and trucks along with the reactions that occur while cooking on grills both can contribute to air pollution and can produce carcinogens.

 

However, Researchers at Oregon State University have discovered that the chemical reactions that occur from these processes produce novel compounds that were not previously known to exist and are hundreds of times more mutagenic than carcinogens.

 

While more research needs to be done to determine in what level the compounds might be present, this raises additional concerns about the health impacts of heavily-polluted urban air and dietary exposure.

 

The parent compounds involved in this research are polycyclic aromatic hydrocarbons, or PAHs, formed naturally as the result of almost any type of combustion, from a wood stove to an automobile engine, cigarette or a coal-fired power plant. Many PAHs are known to be carcinogenic, believed to be more of a health concern that has been appreciated in the past.

 

The PAHs can become even more of a problem when they chemically interact with nitrogen to become "nitrated," or NPAHs, scientists say. The newly-discovered compounds are NPAHs that were unknown to this point.

 

This study found that the direct mutagenicity of the NPAHs with one nitrogen group can increase 6 to 432 times more than the parent compound. NPAHs based on two nitrogen groups can be 272 to 467 times more mutagenic. Mutagens are chemicals that can cause DNA damage in cells that in turn can cause cancer.

 

An agency of the World Health Organization announced last fall that it now considers outdoor air pollution, especially particulate matter, to be carcinogenic, and cause other health problems as well. PAHs are one of the types of pollutants found on particulate matter in air pollution that are of special concern.

 

The findings are published in December in Environmental Science and Technology.