Discrepancy in patch test results with wool wax alcohols and Amerchol registered L-101

Wondering why Amerchol registered L-101 (containing wool wax alcohols obtained from the hydrolysis of wool fall appears as a test material (100%) in a cosmetics series (Chemotechnique Diagnostics AB). as wool wax alcohols were already tested in the European standard series, we added Amerchol registered L-101 (100%) systematically to the standard series, From 8 April 1991 to 28 February 1992. a total of 393 patients were tested: 3.05% (n= l2) showed positive test results (+, ++, +++) for wool wax alcohols as well as Amerchol registered L-101 (100%.), only and 11.1% (n= 44) for Amerchol registered L-101 (100%) only. Thus, the positive tests for Amerchol registered L-101 (100%) had a higher frequency of 3.4 compared to those for wool wax alcohols. In the meantime, we also added Amerchol registered L-101 50% (Trolab) to the standard series. Of all patients tested (n=223) 2.7% (n=6) had positive reactions to wool wax alcohols and 12.1% (n=27) to Amerchol registered L-101 100% and or 50%. Thus, positive reactions to Amerchol registered L-101 (100% and 50%) were 45 higher, whereas the rate of concordancy decreased. It is remarkable that 8 patients only had a positive reaction to Amerchol registered L-101 50% and 9% only to Amerchol registered L-101 1005. It seems that we miss many diagnoses in contact allergy by using only the standard wool wax alcohols test (30%)