Today, antimicrobials are added to many personal care products, such as soaps, mouthwash, toothpaste, hand sanitizers and disinfectants. If your purse is anything like mine, you have a miniature bottle of hand sanitizer with you at all times, especially during cold and flu season. But some experts worry that our society’s overuse of antimicrobials could have some negative effects. These chemicals can be absorbed through the skin when used and end up in the blood stream, breast milk, urine, and eventually sewage and water systems.
A 2011 study found that children and teens with high levels of triclosan, a common antimicrobial used in personal care products, had a greater likelihood of being diagnosed with hay fever and other allergies.This may support the “hygiene hypothesis”, the theory that our society’s overly sterile lifestyle prevents normal stimulation of the immune system and makes us more prone to allergies and allergic diseases. The hypothesis suggests that early exposure to common organisms (germs) is necessary to build proper immune responses. The theory also suggests that lack of this exposure may lead to an overactive immune system that mistakes harmless substances (such as food proteins or pollen) for pathogens, triggering an immune response we know as an allergic reaction.
An NIH-funded study out of Johns Hopkins University, which was published in this month’s edition of the Journal of Allergy and Clinical Immunology, found an association between children’s exposure to antimicrobials and the development of food allergies specifically. The researchers found that in comparison to children with the lowest urine levels of triclosan (the common antimicrobial we discussed in the paragraph above), children with the highest urine levels also had the highest levels of IgE-mediated food allergies. In fact, children with the highest triclosan levels had more than twice the risk for food allergy, in comparison to the children with the lowest triclosan levels.
The researchers say that their findings are consistent with the hygiene hypothesis.
It’s important to note that these findings don’t mean that the use of antimicrobial products causes the development of allergies, just that there is an association between the two. More research is needed to know exactly what relationship exists. Antibacterial products certainly play an important role in preventing the spread of illnesses. Like most things in life, the key is to keep their use in moderation. For example, keeping a bottle of hand sanitizer around to use when hand washing isn’t possible is still a good way to keep your kids healthy but when you are at home; good old soap should do the trick. Similarly, cleaning with a disinfectant spray is useful when a family member is sick and you are trying to keep germs away from the rest of the family but a cleaning spray without disinfectant may work fine for normal circumstances. Keep an eye on antimicrobial additives in your personal care products and limit them where you can.
Savage JH, Matsui EC, Wood RA, Keet CA. Urinary levels of triclosan and parabens are associated with aeroallergen and food sensitization. The Journal of Allergy and Clinical Immunology 2012;130:453-460.
Clayton EMR, Todd M, Dowd JB, Aiello AE 2011. The Impact of Bisphenol A and Triclosan on Immune Parameters in the U.S. Population, NHANES 2003–2006. Environ Health Perspect 119:390-396.