Abstract
A latex allergic patient exhibited a severe local reaction to a non-latex wound closure tape following surgery. A tape sample was extracted in acetonitrile (10 ml/g) and analyzed by GC-EI-MS (Gas Chromatograph-Electron Impact-Mass Spectrometry) in the total ion monitoring mode. Components were identified by their ion mass fingerprint and elution at the same time as a corresponding standard from the GC column. The chemicals identified were 5-tert-butyl-4-hydroxy-2- methylphenyl sulfide (TBHMS), 2-tert-butyl-5-methyl-phenol (TBMP), 2,4-ditert- butylphenol (DTBP), and erucamide (EA). Potential for sensitization for these chemicals was evaluated using two quantitative structure-activity relationship (QSAR) programs. The potential for TBHMS (the most potent sensitizer) to be a sensitizer was predicted by both DEREK for Windows and TOPKAT 6.1. The potential for TBMP and DTBP to induce sensitization was predicted by DEREK for Windows but not TOPKAT. These three phenolic chemicals were then tested for their sensitization potential using a modified local lymph node assay (LLNA). With the exception of TBMP (highest concentration 12.5% due to toxicity) test articles were evaluated at 50%, 25% and 12.5%. None of the animals exhibited body weight loss or skin irritation. LLNA analysis of the chemicals identified TBHMS>TBMP>DTBP as potential sensitizers with EC3 values of 0.2, 4.5, and 6.8 respectively. Following a clinical observation, these studies used a multidisciplinary approach combining GC-EI-MS to identify chemical components, QSAR to prioritize chemicals for animal testing, and the LLNA to determine the sensitization potential of chemicals in the product. Human patch testing will be conducted to confirm these findings.