Various pesticides are used in areas where agriculture is a major industry, as well as in cities where pests such as cockroaches and rodents are common. Major pesticides include the organophosphates, such as chlorpyrifos and diazinon, and the pyrethroids, such as cis- and trans-permethrin.
A study published in 2009 sought to determine the effects of exposure to various types of pesticides on the development of allergies and asthma in children living in New York City. This study found that exposure to diazinon during childhood resulted in less wheezing, coughing and the development of positive allergy tests to pets, dust mites and cockroaches.
On the other hand, exposure to cis-permethrin caused children to cough more frequently, but had no effect on wheezing or the frequency of positive skin tests.
It is not known why diazinon exposure would decrease the amount of allergic disease in children. It would make sense that the use of a pesticide would kill pests such as cockroaches, so there would be fewer pests around to cause allergy symptoms. However, the amount of cockroach allergen wasn't changed in the homes that used diazinon as a pesticide, so the benefit of diazinon decreasing allergies can't be attributed simply to the fact that it decreased the amount of pests inside the home.
Organophosphates, however, are known to drive the immune system away from allergies and towards an infection-fighting mode, which is the most likely explanation for the findings of this study.
Learn more about the prevention of allergies in children.
Source:
Reardon AM, Perzanowski MS, Whyatt RM, et al. Associations Between Prenatal Pesticide Exposure and Cough, Wheeze and IgE in Early Childhood. J Allergy Clin Immunol. 2009;124:852-4. DISCLAIMER: The information contained in this site is for educational purposes only, and should not be used as a substitute for personal care by a licensed physician. Please see your physician for diagnosis and treatment of any concerning symptoms or medical condition.
