Passive Sampling Techniques Episode 4 pot

Use of permeation passive samplers in air monitoring Boz˙ena Zabiegała and Jacek Namies´nik Passive sampling is now a well-established method to monitor pollution of air, especially indo

76 S Wold, C Albano, W.J Dunn, U Edlund, K Esbensen, P Geladi, S Hellberg, E Johansson, W Lindberg and M Sjo ¨stro ¨m, Multivariate Data Analysis in Chemistry In: B.R Kowalski (Ed.), Chemometrics: Mathe-matics and Statistics in Chemistry, D Reidel Publishing Company, Dordrecht, Holland, 1984.

77 A.-L Sunesson, C.-A Nilsson and B Andersson, J Chromatogr A, 699 (1995) 203.

Use of permeation passive samplers in air monitoring

Boz˙ena Zabiegała and Jacek Namies´nik

Passive sampling is now a well-established method to monitor pollution

of air, especially indoor air[1–3] Passive monitoring is generally char-acterized by the same accuracy as active monitoring, but an expensive sampling pump is not needed, which is very advantageous Passive sampling offers considerable potential as a monitoring tool, especially for multi-point sampling over large, remote areas [2] The only disad-vantage of permeation passive samplers seems to be relatively low sampling rates, which requires long sampling times in environments with low pollutant concentrations and the necessity to calibrate passive samplers for each substance due to distinguishing membrane charac-teristics [4] However, long sampling times at low concentrations can also be viewed as an advantage of the permeation passive sampling, as

it makes it easy to determine time-weighted average (TWA) concen-trations of analytes In the overall assessment of the pollutant impact

on human health, TWA concentrations are more useful than short-term concentrations, as they reflect the long-term exposure to these com-pounds Permeation samplers, collecting gaseous pollutants at a rate controlled by permeation through a non-porous membrane, offer unique advantages, including effective moisture elimination and small sensitivity to air currents and temperature variations In the case of indoor air quality measurements, they have the additional advantage of being much more acceptable by the inhabitants of the monitored areas compared to standard techniques based on dynamic sampling using sorption tubes

Membrane-enclosed sorptive coating as integrative sampler for monitoring organic compounds in air

Peter Popp, Heidrun Paschke, Branislav Vrana,

Luise Wennrich and Albrecht Paschke

Membrane-enclosed sorptive coatings (MESCOs) are devices combining the advantages of passive sampling approaches with solvent-free pre-concentration of organic contaminants from air, water or other matri-ces The sampling materials are polymer-coated stir bars, solid-phase microextraction (SPME) fibres or pieces of polymer materials In 2001, Vranaet al [1]first described an integrative passive sampler for mon-itoring organic contaminants in water The authors used a stir bar coated with polydimethylsiloxane (PDMS) as described by Baltussenet

al [2]for the enrichment of the contaminants The PDMS-coated stir bar (‘‘Twister’’) is then thermally desorbed on-line into a capillary gas chromatograph coupled with mass selective detector (GC–MS) system The MESCO used for the first investigations consisted of a stir bar enclosed in a dialysis membrane bag made from regenerated cellulose, filled with double distilled water and sealed at each end with Spectra Por enclosures Another MESCO type used for passive sampling of analytes from water consists of a low-density polyethylene (LDPE) tubing heat-sealed at both ends and filled with PDMS fibres and an inner fluid [3]

Independently from the devices designed for passive sampling in water (described in Chapter 10 of this book) two types of MESCOs for the long-term monitoring of semi-volatile organic air pollutants were also developed Type A consists of an LDPE membrane tubing with

and relative standard deviation (RSD), comparison between slope, axis intercept, coefficient of correlation (r2) and uptake rate (R S )

Compound C Air (ng m
3) RSD (%) Slope (ng h
1) Intercept (ng) r2 R S (mL h
1) Slope (ng h
1) Intercept (ng) r2 R S (mL h
1)