By: Steve Herman
Posted: January 9, 2009, from the January 2009 issue of GCI Magazine.
“Due to a respiratory illness of your dental hygienist—please do not wear perfume or cologne on the day of your appointment. Thank you.” —Sign in my dentist’s office
The potential for allergic reaction is a major concern for the producers of cosmetic products, and extensive work has been done in this field. Respiratory allergy effects can be an important concern regarding fragrance use, but little information is available on this subject. The mechanisms of both reactions are closely related. But exactly how does one determine the respiratory effects of inhaling fragrance? The short answer is: It’s not easy. Something certainly must be measured, and one of those things may well be our old friend IgE (an immunoglobulin that elicits an immune response, explored in the December 2008 “Chemical Reaction” column)—though a host of related signaling molecules are also likely candidates.
The December 2008 “Chemical Reaction” column summarized the recent activities of RIFM and briefly considered the respiratory program, but further attention should be devoted to a recent RIFM paper outlining an approach to the area that was published in 20081. That paper cites TH2-type lymphocyte immune response as a key to respiratory sensitization. It is also suggested that TH1, usually involved in contact sensitization, may have respiratory effects and that there may not be a sharp line between the TH1 and TH2 type response.
It should be remembered that this is part of a broader issue, beyond fragrance, that includes indoor air pollution and environmental atmospheric pollution. The lesson imparted in the paper has broad implications in human health—including the possible connections between dermal and respiratory effects.
Cause and Effect
The basic structure of a T-cell is shown in Figure 1. Six receptor binding sites project out of a globular structure. Parts of the chains are the same in all T-cells, while the ends have variable regions that allow for unlimited structural flexibility to respond to any possible allergens.