« Previous AbstractMachine Learning in Human Olfactory Research    Next Abstract"Modeling the biogenic isoprene emission and its impact on ozone pollution in Zhejiang province, China" »

Environ Toxicol Chem

Title:		Interlaboratory Study of Polyethylene and Polydimethylsiloxane Polymeric Samplers for Ex Situ Measurement of Freely Dissolved Hydrophobic Organic Compounds in Sediment Porewater
Author(s):		Lotufo GR; Michalsen MM; Reible DD; Gschwend PM; Ghosh U; Kennedy AJ; Kerns KM; Rakowska MI; Odetayo A; MacFarlane JK; Yan S; Bokare M;
Address:		"Environmental Laboratory, US Army Engineer Research and Development Center, Vicksburg, Mississippi, USA. Department of Civil, Environmental, and Construction Engineering, Texas Tech University, Lubbock, Texas, USA. Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA. Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, Maryland, USA. Seattle District, US Army Corps of Engineers, Seattle, Washington, USA"
Journal Title:		Environ Toxicol Chem
Year:		2022
Volume:		20220622
Issue:		8
Page Number:		1885 - 1902
DOI:		10.1002/etc.5356
ISSN/ISBN:		1552-8618 (Electronic) 0730-7268 (Print) 0730-7268 (Linking)
Abstract:		"We evaluated the precision and accuracy of multilaboratory measurements for determining freely dissolved concentrations (C(free) ) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in sediment porewater using polydimethylsiloxane (PDMS) and low-density polyethylene (LDPE) polymeric samplers. Four laboratories exposed performance reference compound (PRC) preloaded polymers to actively mixed and static ex situ sediment for approximately 1 month; two laboratories had longer exposures (2 and 3 months). For C(free) results, intralaboratory precision was high for single compounds (coefficient of variation 50% or less), and for most PAHs and PCBs interlaboratory variability was low (magnitude of difference was a factor of 2 or less) across polymers and exposure methods. Variability was higher for the most hydrophobic PAHs and PCBs, which were present at low concentrations and required larger PRC-based corrections, and also for naphthalene, likely due to differential volatilization losses between laboratories. Overall, intra- and interlaboratory variability between methods (PDMS vs. LDPE, actively mixed vs. static exposures) was low. The results that showed C(free) polymer equilibrium was achieved in approximately 1 month during active exposures, suggesting that the use of PRCs may be avoided for ex situ analysis using comparable active exposure; however, such ex situ testing may not reflect field conditions. Polymer-derived C(free) concentrations for most PCBs and PAHs were on average within a factor of 2 compared with concentrations in isolated porewater, which were directly measured by one laboratory; difference factors of up to 6 were observed for naphthalene and the most hydrophobic PAHs and PCBs. The C(free) results were similar for academic and private sector laboratories. The accuracy and precision that we demonstrate for determination of C(free) using polymer sampling are anticipated to increase regulatory acceptance and confidence in use of the method. Environ Toxicol Chem 2022;41:1885-1902. (c) 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA"
Keywords:		"Dimethylpolysiloxanes Environmental Monitoring/methods Geologic Sediments/chemistry Humans Naphthalenes *Polychlorinated Biphenyls/analysis *Polycyclic Aromatic Hydrocarbons/analysis Polyethylene/chemistry Polymers *Water Pollutants, Chemical/analysis Bio;"
Notes:		"MedlineLotufo, Guilherme R Michalsen, Mandy M Reible, Danny D Gschwend, Philip M Ghosh, Upal Kennedy, Alan J Kerns, Kristen M Rakowska, Magdalena I Odetayo, Adesewa MacFarlane, John K Yan, Songjing Bokare, Mandar eng Research Support, U.S. Gov't, Non-P.H.S. 2022/05/06 Environ Toxicol Chem. 2022 Aug; 41(8):1885-1902. doi: 10.1002/etc.5356. Epub 2022 Jun 22"