title: Interlaboratory study for the polychlorinated naphthalenes (PCNs): phase 1 results.
abstract: An interlaboratory study was initiated to investigate consistency in reported concentrations of polychlorinated naphthalenes (PCNs). Results are reported from the first phase of a study that examined the variability associated with different quantification methodologies, instrumentation and standards. Nine participating labs from seven countries quantified individual homolog groups, summation operator PCN (the sum of 2-8 chlorinated homologs), and selected congeners in two test solutions derived from Halowax 1014. The means of the reported summation operator PCN values were within less than 15% of the known concentrations of the two test solutions and the relative standard deviation among laboratories was 11%. However, the among laboratory variability was in the range 20-40% for individual PCN homologs and individual PCN congeners. These results suggest the need for additional interlaboratory studies and for the development of reference materials for PCN analysis. Future PCN interlaboratory comparison exercises are discussed that will utilize control materials and unknowns consisting of suitable environmental matrices.
authors.affiliation: ARQM Atmospheric Environment Service, Environment Canada, 4905 Dufferin St., Downsiew, Toronto, Ont., Canada M3H 5T4. tom.harner@ec.gc.ca
authors.forename: Tom
authors.initials: T
authors.lastname: Harner
authors.forename: John
authors.initials: J
authors.lastname: Kucklick
mesh_terms: D017606:Chlorine Compounds / Q000032:analysis*; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D007753:Laboratories; D009281:Naphthalenes / Q000032:analysis*; D015588:Observer Variation; D015203:Reproducibility of Results
chemical_list: D017606:Chlorine Compounds; D004785:Environmental Pollutants; D009281:Naphthalenes