Exposure to triclosan and bisphenol A augment allergic responses in a murine model of asthma.
Anderson-SE; Lukomska-E; Anderson-K; Meade-BJ
Toxicologist 2012 Mar; 126(Suppl 1):162
During the past several decades there has been a remarkable and unexplained increase in the prevalence of asthma. While the hygiene hypothesis provides one potential explanation, individuals in industrial societies are also inadvertently exposed to an increasing number of chemicals. While many chemicals are known to directly induce asthma there is also the potential for non-sensitizing chemicals to augment the immune response induced by other allergens. Our lab has previously demonstrated that dermal application of the environmentally relevant chemical, perflourooctanonic acid, simultaneously with exposure to a single concentration of protein allergen (OVA) was found to augment the allergic response to that allergen. Triclosan and Bisphenol-A (BPA) are widely used chemicals found in both occupational and public environments which have recently been associated with increases in allergy and asthma. BPA, considered to be non-sensitizing, is a substrate of polycarbonate plastics and has been produced in increasingly large quantities since the 1950s. BPA is used to form plastic bottles, as a lining for food and beverage cans, and as a flame retardant. Triclosan is an antibacterial compound that has been used in consumer products for 40 years and is currently found in many hand sanitizers and lotions. The tolerability and safety of triclosan has been evaluated in human volunteers with little indication of toxicity or sensitization. For these studies a murine model of asthma was used to evaluate the immunomodulatory effect of coexposure to BPA or triclosan with OVA. Co-exposure to each of these chemicals individually (as low as 30% BPA and 1.5% triclosan) with OVA resulted in an at least a 2-fold increase in OVA-specific IgE and an augmentation of the airway hyper-reactivity response to methacholine challenge (as low as 7% BPA and 0.75% triclosan) as compared to OVA exposure alone. Understanding the mechanisms by which mixed exposures influence and augment asthma and asthma-like symptoms may lead to better prevention strategies for those at risk for asthma.
Allergens; Chemical-hypersensitivity; Allergic-reactions; Bronchial-asthma; Lung-disorders; Lung-function; Respiratory-system-disorders; Pulmonary-disorders; Immune-reaction; Proteins; Antibacterial-agents; Plastic-products; Flame-retardants; Immunochemistry; Immunological-tests; Dose-response; Airway-resistance; Methacholines
The Toxicologist. Society of Toxicology 51st Annual Meeting and ToxExpo, March 11-15, 2012, San Francisco, California