Dr. David O. Carpenter, director of the Institute for Health and the Environment, at the State University of New York at Albany, said these results are consistent with the hypothesis that simply living near a waste site constitutes a risk of exposure to contaminants, presumably by air transport, and that these chemicals can reduce immune system function and lead to more infections.

New York State has nearly 900 identified hazardous waste sites or highly contaminated bodies of water. Carpenter and colleagues examined rates of hospitalization in New York for acute respiratory infections and asthma by area of residence for children ages 0 to 9 years.

Carpenter, who reported the study this week in Germany at the annual meeting of the European Respiratory Society, told Reuters Health: "Our major finding is that children living near to waste sites, whether landfills or contaminated bodies of water, are hospitalized more frequently with acute respiratory infections," compared to children living in "clean" areas.

"This remains true even after controlling for other known risk factors, such as socioeconomic status, race and sex," he said.

The degree to which exposure to these contaminants suppresses immune system function has been "underestimated," Carpenter added.

Unexpectedly, rates of hospitalization for asthma were also increased in children living near a hazardous waste site. "Asthma is a disease due to an overactive immune system, and we had expected that we would see a reduced rate of hospitalization for asthma," Carpenter said.

"However, we are looking at asthmatics that are hospitalized for a very severe attack, and on consideration we now suspect that this occurs primarily when an asthmatic also has an infection." His team plans additional studies to test whether this is the case.

Summing up, Carpenter said this study shows that exposure to organic pollutants and other contaminants can harm health and just living near to a contaminated site may cause exposure.

"While our specific study focused on air transport of the contaminants, they are also in our food," Carpenter noted, "and the effect of exposure should not be different whether it is via food or air. So we really need to get these chemicals out of our environment to the greatest degree possible."