title: Validation of transferability of DBA derivatization and LC-MS/MS determination method for isocyanates via an interlaboratory comparison.
abstract: An adapted method for the quantitative determination of isocyanates in air was implemented and validated in-house. The method was based on air sampling using an impinger flask containing di-n-butylamine (DBA) in toluene and a glass fibre filter in series. The DBA derivatives were determined using liquid chromatography and tandem mass spectrometry. Studied isocyanates were isophorone diisocyanate, isocyanic acid (ICA), methyl isocyanate, ethyl isocyanate, propyl isocyanate, hexamethylene diisocyanate (HDI), 2,6- and 2,4-toluene diisocyanate, 4,4'-methylene diphenyl diisocyanate (MDI), phenyl isocyanate (PhI), MDI oligomers and different HDI adducts. Monitoring of selected reactions resulted in quantifications with correlation coefficients >0.995, within-batch relative standard deviation (RSD) of repeatability was <13% for all analytes. Between-batch RSD (reproducibility) was determined for all the compounds with the exception of the adducts and oligomers and was also <13%. As an additional validation procedure, the method was evaluated by exchanging field (air) and standard samples between two laboratories. The RSDs observed by the two laboratories were comparable. The concentrations determined were between 80 and 120% of each other, depending on the analyte and the individual concentrations. The method was applied in a large field study on exposure of workers in car repair shops and industrial painters with >500 samples.
authors.affiliation: TNO Quality of Life, Quality and Safety, Utrechtseweg 48, 3700 AJ Zeist, The Netherlands. ivana.bobeldijk@tno.nl
authors.forename: Ivana
authors.initials: I
authors.lastname: Bobeldijk
authors.forename: Daniel
authors.initials: D
authors.lastname: Karlsson
authors.forename: Anjoeka
authors.initials: A
authors.lastname: Pronk
authors.forename: John
authors.initials: J
authors.lastname: Gonsalves
authors.forename: Maarten
authors.initials: M
authors.lastname: Hekman
authors.forename: Dick
authors.initials: D
authors.lastname: Van De Lagemaat
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Preller
authors.forename: Dick
authors.initials: D
authors.lastname: Heederik
authors.forename: Gunnar
authors.initials: G
authors.lastname: Skarping
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis*; D002082:Butylamines; D002853:Chromatography, Liquid / Q000379:methods; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods; D007221:Industry; D017953:Isocyanates / Q000032:analysis*; D007753:Laboratories; D016273:Occupational Exposure / Q000032:analysis; D010150:Paint; D011140:Polyurethanes; D053719:Tandem Mass Spectrometry / Q000379:methods; D014051:Toluene 2,4-Diisocyanate
chemical_list: D000395:Air Pollutants, Occupational; D002082:Butylamines; D017953:Isocyanates; D011140:Polyurethanes; D014051:Toluene 2,4-Diisocyanate; C045274:dibutylamine