Allergies correlated to triclosan amounts

A study by the University of Michigan (U-M) School of Public Health [1] suggests that young people exposed to triclosan - a substance used in some soaps, cleansers, toothpastes and other personal care products - may be subject to increased allergy risks.

Researchers at the U-M used data from the 2003-2006 National Health and Nutrition Examination Survey [2] to compare the amounts of triclosan found in urine with diagnosis of allergies or hay fever in a sample of U.S. adults and children over age 6. They found that people age 18 and under with higher levels of triclosan were more likely to report diagnosis of allergies and hay fever.

Hygiene hypothesis

The authors said the study findings may support the “hygiene hypothesis,” which argues that living in excessively clean and hygienic environments may be detrimental to the development of the human immune system that require some level of exposure to micro-organisms.

Previous animal studies indicate that triclosan, known as an endocrine-disrupting compound (EDC), may affect the immune system, but this is the first known study to look at exposure to triclosan as it relates to human immune function, said Allison Aiello, associate professor at the U-M School of Public Health.

No causal link

However, U-M researchers added they need additional studies to check if a causal relationship can be established between the use of triclosan and the higher frequency of hay fever and allergy diagnoses.

One limitation of the study is that it measured disease and exposure simultaneously and thus shows only part of the picture,” Aiello said. “It is possible, for example, that individuals who have an allergy are more hygienic because of their condition, and that the relationship we observed is, therefore, not causal or is an example of reverse causation.

The lack of any causal link in the study form most of the critics expressed by the American Cleaning Institute (ACI – formerly The Soap and Detergent Association), which represents the US cleaning products industry.

This is speculation at its worst. The researchers do not provide data to show a problematic cause-and-effect from usage of antibacterial soap containing triclosan,” said Richard Sedlak, ACI’s Senior Vice President of Technical & International Affairs.

ACI doesn’t want this mythmaking and fear-mongering to discourage individuals from engaging in important cleaning and disinfecting practices. Smart, targeted hygiene is essential to preventing the spread of germs and illness that can truly make us sick or even kill us,” he added.