'Safe' Levels of Pollutants May Cause Long-term Health Problems: A Study

Exposure to pollutants, even in officially established "safe" levels, have a wide range of adverse health effects, including metabolic health, a new study shows.

Published in The FASEB Journal, the report looked at two groups of obese mice, both of which were fed high-fat, high-sucrose diets. Only one group, however, received a cocktail of pollutants at very low dosages throughout their lifespans, starting with from pre-conception.

While the researchers did not observe outright toxicity or excess weight gain in the group fed the pollutants, they did note a marked deterioration of glucose tolerance in females, which suggested a defect in insulin signaling. Furthermore, the study results suggested the pollutants reduced estrogen activity in the liver through the enhancement of an enzyme responsible for estrogen elimination.

Males, meanwhile, showed changes in regards to cholesterol synthesis and transport.

Altogether, the results strengthen the argument that exposure to a wide range of pollutants, even in levels deemed safe, could contribute to a number of chronic illnesses, including metabolic disease and diabetes, according to the study's authors.

"This report that confirms something we've known for a long time: pollution is bad for us," said Dr. Gerald Weissmann, editor-in-chief of The FASEB Journal. "But, what's equally important, it shows that evaluating food contaminants and pollutants on an individual basis may be too simplistic. We can see that when 'safe' levels of contaminants and pollutants act together, they have significant impact on public health."

For this reason, says Brigitte Le Magueresse-Battistoni, a researcher involved in the work from the French National Institute of Health and Medical Research, the study could have major implications in terms of food security, among other things.

"Indeed, one pollutant could have a different effect when in mixture with other pollutants," she said.