Environmental pollution has often been linked to allergies and asthma, but two recent studies  shed new light on why kids in one house develop these conditions while kids exposed to similar pollution levels in the house next door do not. (Note: An additional study was published on Aug. 2 that connects the risk of asthma with mold in the home.)

In the first study, researchers at Columbia University looked at several New York City neighborhoods. In one, nearly one in five kids — or 19 percent — have asthma, while in others, the asthma rate is as low as 3 percent. Pollution sources, such as car traffic, were similar for the neighborhoods, but the study's authors found that it was exposure to cockroaches that raised the kids' risk for developing asthma.  

The study, published in the Journal of Allergy and Clinical Immunology, found that nearly one in four kids living in neighborhoods with high asthma rates were allergic to cockroaches, compared to one in 10 kids living in areas where asthma is less common. The children living in neighborhoods with high rates of asthma were twice as likely to carry antibodies against a cockroach protein in their blood, indicating that they had been exposed to the insects and were also allergic to them.

Another study, this one from researchers at the German Research Center for Environmental Health in Neuherberg, looked at the link between mold and asthma. The study, published in the European Respiratory Journal, found that children who live in homes with visible mold problems have a greater risk of developing asthma and allergies than children who don't live in moldy homes.

The researchers looked at cases from 61 international studies since the 1990s. They found that children living in water-damaged, moldy homes were more likely to have asthma, wheezing problems or nasal allergies than their peers.

So the bottom line from both studies is that it is more important than ever to not only get rid of cockroaches and visible mold, but also to prevent them both from occurring in the first place. Store food in sealed containers, fix leaky plumbing and other sources of water damage, and open windows or install fans to improve ventilation. Your whole family will breathe easier!

Mold, cockroaches linked to asthma and allergies
Two studies link critters and mold to the development of allergies and asthma.