10,000 Urine Samples
Chemicals in tap water may be to blame for higher-than-ever rates of food allergies in the United States, say researchers from the Albert Einstein college of Medicine.
Thanks to data gleaned from the CDC's National Health and Nutrition Survey, scientists were able to scrutinize urine samples from over 10,000 Americans.
What they found is that more than 2,200 samples contained measurable levels of dichlorophenol, a chemical commonly used to chlorinate drinking water and, in the agricultural context, to fend off pests.
Of those individuals with measurable levels of dichlorephenol, 411 had some kind of food allergy, and more than 1,000 had some kind of environmental allergy, such as to pollen or spores.
Correlation, Not Causation
It is important to note that while results of the study show a correlation between the presence of chemicals and allergies, they do not establish a causal link between the two.
"Previous studies have shown that both food allergies and environmental pollution are increasing in the U.S.," the study's lead author, Dr. Elina Jerschow, told Science World News. "The Results of our study suggest these 2 trends might be linked, and that increased use of pesticides and other chemicals is associated with a higher prevalence of food allergies."
The analysis, which appears in the December issue of Annals of Allergy, Asthma and Immunology, did not determine whether exposure through tap water or through pesticide ingestion had a stronger correlation with allergies.