High-performance liquid chromatography identification, quantification, and fractionation of a suspect allergen, 4-chloro-3-methylphenol, in an LLNA-positive metalworking fluid.
Tribol Trans 2008 Jan; 51(1):101-106
A metalworking fluid (MWF) was obtained that produced an allergic reaction in the local lymph node assay (LLNA) with an EC3 = 4%, the EC3 being the estimated concentration needed to provoke a 3-fold allergy response. High-performance liquid chromatography (HPLC) was used to separate, identify, and isolate the suspected allergen. The biocide, 4-chloro-3-methylphenol, was detected in the MWF as a chromatographic peak matching the retention time of an external standard. The technique of standard addition was used to quantify and confirm the presence of 4-chloro-3-methylphenol at about 1% (w/w). Preparative HPLC was used to fractionate 1 gram of MWF separating the 4-chloro-3-methylphenol fraction from the remaining MWF. The two mobile-phase solutions were concentrated back into an MWF and a 4-chloro-3-methylphenol fraction. The original MWF and the reconstituted 4-chloro-3-methylphenol and MWF fractions were also analyzed by gas chromatography-mass spectrometry to confirm the isolation of the biocide.
Metalworking-fluids; Allergens; Allergic-reactions; Chromatographic-analysis; Lymph-nodes; Bioassays; Spectrographic-analysis; Gas-liquid-chromatography; Biocides; Toxicology; Chemical-analysis; Lubricants; Liquid-chromatography
National Institute for Occupational Safety and Health, Division of Applied Research and Technology, 4676 Columbia Parkway, Cincinnati, OH 45226