Quaternary Ammonium and Immunization in Hairdressers

Quaternary ammonium ions (QA) are surfactants and microbicide products found in a large number of household products, disinfectants and cosmetics.

Professional exposure to QA causes allergic diseases of the skin and lung (asthma). It is also the first cause of occupational rhinitis since 2000.

Several studies have found a link between exposure to some disinfectants and asthma in specific population. The responsibility of the QA in asthma can be demonstrated by in vivo testing (inhalation challenge). Some QA have been shown to directly activate the immune system, in particular didecyldimethylammonium chloride, a common disinfectant, that was demonstrated to act as a sensitizer.

Neuromuscular blocking agents (NMBA) are drugs used during surgery to relax muscles. They all have QA moieties and can trigger sometimes severe IgE-mediated allergic reaction (anaphylaxis). The epitope of these drugs recognized by the Immunoglobulin E (IgE) antibodies are precisely the QA moieties. However, the origin of these IgE is unknown as a significant proportion of patients have anaphylaxis on the first exposure an NMBA. A study showed that exposure to QA found in hairdressing products was linked to anti-IgE QA and then might also be a risk factor to allergy to NMBA.

Thus, QA exposure is strongly suspected to be linked to allergic diseases. However, the prevalence of QA sensitization amongst hairdressers is not known, sensitization mechanisms have been poorly characterized. To date, there is no recommendation regarding QA exposure nor classification of QA by toxicity. Finally, the link between hairdressing QA and drug allergy have not been confirmed yet.