Passive air samplers (PASs) operate in different types of environment under various wind conditions, which may affect sampling rates and thus introduce uncertainty to PAS-derived air concentrations. To quantify the effect of wind speed and angle on the uptake in cylindrical PASs using XAD-resin as the sampling medium, we measured the uptake kinetics of polychlorinated biphenyls (PCBs) in XAD an...

Controlled laboratory experiments were conducted to demonstrate the use of passive samplers for soil vapor concentration monitoring. Five different passive samplers were studied (Radiello, SKC Ultra, Waterloo Membrane Sampler, ATD tubes and 3M OVM 3500). Ten different volatile organic compounds were used of varying classes (chlorinated ethanes, ethanes, and methanes, aliphatics and aromatics) a...

We consider a Gibbs sampler applied to the uniform distribution on a bounded region R ⊆ R. We show that the convergence properties of the Gibbs sampler depend greatly on the smoothness of the boundary of R. Indeed, for sufficiently smooth boundaries the sampler is uniformly ergodic, while for jagged boundaries the sampler could fail to even be geometrically ergodic.

This paper presents a field evaluation of a passive badge for measuring 2-ethoxyethyl acetate (2-EEAc) in a humid working environment. Forty-eight pairs of side-by-side active/passive 8-h full-shift personal samples were collected to evaluate the performance of a passive badge for monitoring 2-EEAc with the co-exposure of toluene and methyl iso-butyl ketone (MIBK) in a warm and humid workplace....

The use of thin-film polymer-coated glass surfaces or POGs as passive air samplers was investigated during an uptake experiment in an indoor environment with high levels of gas-phase polychlorinated biphenyls (PCBs). POGs consisted of a micron thick layer of ethylene vinyl acetate (EVA) coated onto glass cylinders. The uptake was initially linear with time and governed by the air-side mass tran...

We consider a Gibbs sampler applied to the uniform distribution on a bounded region R R d. We show that the convergence properties of the Gibbs sampler depend greatly on the smoothness of the boundary of R. Indeed, for suuciently smooth boundaries the sampler is uniformly ergodic, while for jagged boundaries the sampler could fail to even be geometrically ergodic.

Because the atmosphere is key to understanding the environmental behavior of volatile methyl siloxanes (VMS), a variety of reliable air sampling methods are needed. The purpose of this study was to calibrate and evaluate an existing, polystyrene-divinylbenzene copolymeric resin-based passive air sampler (XAD-PAS) for VMS. Sixteen XAD-PAS were deployed for 7-98 days at a suburban site in Toronto...

Improving methods for assessing the spatial and temporal resolution of organic compound concentrations in marine environments is important to the sustainable management of our coastal systems. Here we evaluate the use of ethylene vinyl acetate (EVA) as a candidate polymer for thin-film passive sampling in waters of marine environments. Log K(EVA-W) partition coefficients correlate well (r(2) = ...

Passive sampling of organic pollutants is a new trend in environmental monitoring and analysis. Passive samplers are being developed to overcome the drawbacks of the conventional snapshot sampling approach. The ceramic toximeter is a promising passive sampler for monitoring dioxin-contaminated surface and ground waters. It consists of an alumina cylinder lined with a thin coating of titania and...

Evaluation of published methods reveals that existing methods for saliva sampling do not address the physical-chemical attributes of volatile organic compounds (VOCs). This study describes and presents evidence for adopting in situ sampling of salivary VOCs directly from the oral cavity using a polydimethylsiloxane (PDMS) based sampler. In vitro studies indicated that the vapour pressure of ana...