title: Sampling artifacts in active air sampling of semivolatile organic contaminants: Comparing theoretical and measured artifacts and evaluating implications for monitoring networks.
abstract: The effects of sampling artifacts are often not fully considered in the design of air monitoring with active air samplers. Semivolatile organic contaminants (SVOCs) are particularly vulnerable to a range of sampling artifacts because of their wide range of gas-particle partitioning and degradation rates, and these can lead to erroneous measurements of air concentrations and a lack of comparability between sites with different environmental and sampling conditions. This study used specially adapted filter-sorbent sampling trains in three types of active air samplers to investigate breakthrough of SVOCs, and the possibility of other sampling artifacts. Breakthrough volumes were experimentally determined for a range of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) in sampling volumes from 300 to 10,000 m(3), and sampling durations of 1-7 days. In parallel, breakthrough was estimated based on theoretical sorbent-vapor pressure relationships. The comparison of measured and theoretical determinations of breakthrough demonstrated good agreement between experimental and estimated breakthrough volumes, and showed that theoretical breakthrough estimates should be used when developing air monitoring protocols. Significant breakthrough in active air samplers occurred for compounds with vapor pressure >0.5 Pa at volumes <700 m(3). Sample volumes between 700 and 10,000 m(3) may lead to breakthrough for compounds with vapor pressures between 0.005 and 0.5 Pa. Breakthrough is largely driven by sample volume and compound volatility (therefore indirectly by temperature) and is independent of sampler type. The presence of significant breakthrough at "typical" sampling conditions is relevant for air monitoring networks, and may lead to under-reporting of more volatile SVOCs.
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Faculty of Science, Masaryk University, Kamenice 5/753, 625 00 Brno, Czech Republic. Electronic address: melymuk@recetox.muni.cz.
authors.forename: Lisa
authors.initials: L
authors.lastname: Melymuk
authors.affiliation: NILU, Norwegian Institute for Air Research, P.O. Box 100, NO-2027 Kjeller, Norway.
authors.forename: Pernilla
authors.initials: P
authors.lastname: Bohlin-Nizzetto
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Faculty of Science, Masaryk University, Kamenice 5/753, 625 00 Brno, Czech Republic.
authors.forename: Roman
authors.initials: R
authors.lastname: Prokeš
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Faculty of Science, Masaryk University, Kamenice 5/753, 625 00 Brno, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Kukučka
authors.affiliation: Research Centre for Toxic Compounds in the Environment (RECETOX), Faculty of Science, Masaryk University, Kamenice 5/753, 625 00 Brno, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Klánová
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D016477:Artifacts; D004784:Environmental Monitoring / Q000379:methods*; D055768:Halogenated Diphenyl Ethers / Q000032:analysis*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D055768:Halogenated Diphenyl Ethers; D006843:Hydrocarbons, Chlorinated; D011084:Polycyclic Aromatic Hydrocarbons; D011078:Polychlorinated Biphenyls
keywords: Air sampling; Breakthrough; Persistent organic pollutants; Sampling artifacts; Semivolatile organic contaminants