title: Findings from quality assurance activities in the Integrated Atmospheric Deposition Network.
abstract: A series of experiments were conducted among the laboratories participating in the Integrated Atmospheric Deposition Network (IADN) monitoring program to evaluate comparability of the reported persistent organic pollutant concentrations. This quality assurance activity is essential because a variety of methods are currently used for sample collection, extraction, and analysis by the IADN laboratories. The experiments included analyses of a common reference standard (CRS), analyses of split samples, and analyses of samples collected with co-located samplers at the Point Petre IADN measurement station. The analytes included polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs). For virtually all compounds, the laboratories produced generally comparable results for the CRS samples, the split samples and the co-location samples, although some differences were observed. Analysis of the methods may pinpoint areas where variations in the methods will result in the differences observed in the reported data. These differences can be due to the field sampling process, the analytical method, field blank values, or a combination of all these factors. This study points out the importance of QA activities at every step of an environmental monitoring process so that areas where improvements may be needed or where inconsistencies may exist can be identified.
authors.affiliation: Air Quality Research Division, Science & Technology Branch, Environment Canada, Toronto, ON, Canada M3H 5T4.
authors.forename: Rosa
authors.initials: R
authors.lastname: Wu
authors.forename: Sean
authors.initials: S
authors.lastname: Backus
authors.forename: Ilora
authors.initials: I
authors.lastname: Basu
authors.forename: Pierrette
authors.initials: P
authors.lastname: Blanchard
authors.forename: Kenneth
authors.initials: K
authors.lastname: Brice
authors.forename: Helena
authors.initials: H
authors.lastname: Dryfhout-Clark
authors.forename: Peter
authors.initials: P
authors.lastname: Fowlie
authors.forename: Melissa
authors.initials: M
authors.lastname: Hulting
authors.forename: Ronald
authors.initials: R
authors.lastname: Hites
mesh_terms: D002170:Canada; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D015233:Models, Statistical; D010575:Pesticides / Q000032:analysis*; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D011786:Quality Control; D012015:Reference Standards; D012680:Sensitivity and Specificity; D014481:United States
chemical_list: D004785:Environmental Pollutants; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D011084:Polycyclic Aromatic Hydrocarbons; D011078:Polychlorinated Biphenyls