TESTING WITH FRAGRANCE MIX - IS THE ADDITION OF SORBITAN SESQUIOLEATE TO THE CONSTITUENTS USEFUL - RESULTS OF A MULTICENTER TRIAL OF THE EUROPEAN ENVIRONMENTAL AND CONTACT-DERMATITIS RESEARCH GROUP (EECDRG)

In a multicentre study, the value of adding sorbitan sesquioleate (SSO) to the constituents of the 8% fragrance mix (FM) was investigated. In 7 centres, 709 consecutive patients were tested with 2 types of FM from different sources, its 8 constituents with 1% SSO, its 8 constituents without SSO, and 20% SSO. 5 patients (0.71%) reacted to the emulsifier SSO itself, read as definitely allergic on day 3/4. 53 patients reacted to either one of the mixes with an allergic type of reaction. When tested with the constituents without SSO, 41.5% showed an allergic reaction versus 54.7% with SSO. If both types of reactions were considered (allergic and irritant) 38.3% of 73 patients showed a positive ''breakdown'' result without SSO, versus 54.8% with SSO. The differences were statistically significant. Reactivity to FM constituents was changed in a specific pattern by addition of SSO- irritant reactions increased, particularly for cinnamic alcohol, eugenol, geraniol, oak moss and hydroxycitronellal, whereas others showed only a slight change. Allergic reactions were also increased by SSO, but the rank order of the top 3 sensitizers (isoeugenol, oak moss and eugenol) did not change. Cinnamic alcohol was the only constituent with decreased reactivity after addition of SSO. A positive history of fragrance sensitivity (HFS) was clearly associated with a positive allergic reaction to either the mix or 1 of its constituents (51% versus 28.6% with a negative HFS). Irritant reactions were linked to a negative HFS in a high proportion (64.3%). In 17 patients, a repeated open application test (ROAT) was performed with a total of 43 patch-test-positive materials. The ROAT was positive in 20/31 (64.5%) tests in 11 patients with a positive HFS, but negative in all 6 patients with a negative HFS (0/12 tests). In conclusion, addition of SSO to the constituents of FM increases both irritant and allergic reactions, though the difference from the results without SSO is not as high as previously reported. The ROAT is a valuable tool in validating such patch test results.