Calibration of Silicone Rubber Passive Samplers: Experimental and Modeled Relations between Sampling Rate and Compound Properties

Abstract

Sampling rates (Rs) for silicone rubber (SR) passive samplers were measured under two different hydrodynamic conditions. Concentrations were maintained in the aqueous phase by continuous equilibration with SR sheets of a large total surface area which had been spiked with polycyclic aromatic hydrocarbons and/or polychlorinated biphenyls. Test sheets made of the same SR but of much smaller surface area were used to measure the uptake rate. Measured Rs values decreased with increasing passive sampler-water partition coefficient (Kpw) according to Rs approximately Kpw(-0.08) under both hydrodynamic conditions. This decrease is not significantly different from modeled values if the uncertainty of the diffusion coefficients in water is included. Modeling also confirmed that uptake of the test compounds under the experimental conditions was entirely controlled by diffusion in the water phase. A model using Rs approximately M(-0.47) is suggested for extrapolation of Rs estimated from the dissipation of performance reference compounds to target compounds in a higher hydrophobicity range.

An interlaboratory study on passive sampling of emerging water pollutants

“…The PT scheme revealed that most of the participating laboratories were able to analyse PAHs, PCBs and PBDEs in SR with a satisfactory z-score (<2). Most laboratories also showed a good performance in application of existing models [12,13] available for translation of passive sampling data into water concentrations. The inter-laboratory study presented here was organised in 2011 by the NORMAN association (Network of reference laboratories for monitoring emerging environmental pollutants; www.norman-network.net ) together with the European DG Joint Research Centre as a follow-up of the above mentioned exercise.…”

“… In case no equilibrium is attained, aqueous concentrations should be estimated by sampler/water exchange kinetics models that can be in situ calibrated from the release of PRCs dosed to the sampler prior to exposure [12]. Booij and Smedes [13] recommend that efforts to reduce the bias and variability in water concentration estimates should primarily focus on reducing the uncertainties in the K sw values of the PRCs.…”

Air and seawater pollution and air–sea gas exchange of persistent toxic substances in the Aegean Sea: spatial trends of PAHs, PCBs, OCPs and PBDEs

“…The sampling method is based on diffusion and absorption of hydrophobic contaminants from water to the silicone rubber polymer (Rusina et al 2007(Rusina et al , 2010. Each sampler consisted of six sheets (55×90× 0.5 mm).…”

Uptake and release kinetics of 22 polar organic chemicals in the Chemcatcher passive sampler

“…However, in which way sorption and desorption are indeed not isotropic requires confirmation in an experiment where these processes are investigated simultaneously in a single experiment [32].…”