Can the use of deactivated glass fibre filters eliminate sorption artefacts associated with active air sampling of perfluorooctanoic acid?. (May 2017)

• Record Type: Journal Article
• Authors: Johansson, Jana H.; Berger, Urs; Cousins, Ian T.
• Is Part Of: Environmental pollution. Volume 224(2017)
• Page Start: 779
• Page End: 786
• Publication Date: 2017-05
• Subjects: Air sampling -- Sorption -- PFOA -- Siliconisation -- Silylation; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2017.01.020
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Experimental work was undertaken to test whether gaseous perfluorooctanoic acid (PFOA) sorbs to glass fibre filters (GFFs) during air sampling, causing an incorrect measure of the gas-particle equilibrium distribution. Furthermore, tests were performed to investigate whether deactivation by siliconisation prevents sorption of gaseous PFOA to filter materials. An apparatus was constructed to closely simulate a high-volume air sampler, although with additional features allowing introduction of gaseous test compounds into an air stream stripped from particles. The set-up enabled investigation of the sorption of gaseous test compounds to filter media, eliminating any contribution from particles. Experiments were performed under ambient outdoor air conditions at environmentally relevant analyte concentrations. The results demonstrate that gaseous PFOA sorbs to GFFs, but that breakthrough of gaseous PFOA on the GFFs occurs at trace-level loadings. This indicates that during high volume air sampling, filters do not quantitatively capture all the PFOA in the sampled air. Experiments with siliconised GFFs showed that this filter pre-treatment reduced the sorption of gaseous PFOA, but that sorption still occurred at environmentally relevant air concentrations. We conclude that deactivation of GFFs does not allow for the separation of gaseous and particle bound perfluorinated carboxylic acids (PFCAs) during active air sampling. Consequently, the well-recognised theory that PFCAs do not prevail as gaseous species in the atmosphere may be based on biased measurements. Caution should be taken to ensure that this artefact will not bias the conclusions of future field studies. Graphical abstract: Highlights: Gaseous PFOA partially sorbs to glass fibre filters (GFFs) during air sampling. The amount found on GFFs represents both gaseous and particulate PFOA. Traditional active air sampling cannot measure gas-particle partitioning of PFOA. We stress the importance of monitoring filter breakthrough. Siliconisation of GFFs can reduce but not eliminate sorption of PFOA. Abstract : Gaseous PFOA sorbs to glass fibre filters during high volume environmental air sampling and although this sorption can be reduced by deactivation of the filters it cannot be eliminated.