Passive sampling methods for contaminated sediments: Scientific rationale supporting use of freely dissolved concentrations

Abstract

Passive sampling methods (PSMs) allow the quantification of the freely dissolved concentration (Cfree) of an organic contaminant even in complex matrices such as sediments. Cfree is directly related to a contaminant's chemical activity, which drives spontaneous processes including diffusive uptake into benthic organisms and exchange with the overlying water column. Consequently, Cfree provides a more relevant dose metric than total sediment concentration. Recent developments in PSMs have significantly improved our ability to reliably measure even very low levels of Cfree. Application of PSMs in sediments is preferably conducted in the equilibrium regime, where freely dissolved concentrations in the sediment are well-linked to the measured concentration in the sampler via analyte-specific partition ratios. The equilibrium condition can then be assured by measuring a time series or a single time point using passive samplers with different surface to volume ratios. Sampling in the kinetic regime is also possible and generally involves the application of performance reference compounds for the calibration. Based on previous research on hydrophobic organic contaminants, it is concluded that Cfree allows a direct assessment of 1) contaminant exchange and equilibrium status between sediment and overlying water, 2) benthic bioaccumulation, and 3) potential toxicity to benthic organisms. Thus, the use of PSMs to measure Cfree provides an improved basis for the mechanistic understanding of fate and transport processes in sediments and has the potential to significantly improve risk assessment and management of contaminated sediments. Integr Environ Assess Manag 2014;10:197–209. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC.

A re‐evaluation of PETROTOX for predicting acute and chronic toxicity of petroleum substances

“…Initially the limit identified in Equation 1 was parameterized at log K OW of 6 [9,[40][41][42][43], which effectively reduced the bioavailability of more hydrophobic components while allowing fractional contribution to overall toxicity of the substance to be included in P TU calculations [44][45][46]. This nonlinear partitioning behavior may reflect the impact of low solubility and slow toxicokinetics [47] or other competing processes that limit accumulation in the target lipid for these low-solubility constituents.…”

Application of passive sampling for measuring dissolved concentrations of organic contaminants in the water column at three marine superfund sites

“…After the 33 day exposure, mussels were recovered, returned to the laboratory in coolers on ice, frozen at -4 ºC, 281 and stored in the dark until chemical analysis. where, k e is the PRC transfer coefficient (1/day) and t (day) the duration of the deployment: where, C lipid is the lipid-normalized PCB concentration measured in the mussel tissues [5]. other treatments while C free based on SPME and total water were not different, total water and 355 SPMD C free were also not different, and, finally, SPMD and C 18 -based C free were not different.…”

Quality Standard Setting and Environmental Monitoring

“…As previously mentioned for PSDs in the water column, recent developments in PSMs have significantly improved our ability to reliably measure even very low levels of C free (Mayer et al, 2014). A brief overview of these five papers has been proposed by Parkenson and Maruya (2014), who emphasize the needs for future research and communication for future consensus among the science, management, and practitioners on the appropriate use of PSMs in supporting contaminated sediment management (Mayer et al, 2014). A brief overview of these five papers has been proposed by Parkenson and Maruya (2014), who emphasize the needs for future research and communication for future consensus among the science, management, and practitioners on the appropriate use of PSMs in supporting contaminated sediment management (Mayer et al, 2014).…”