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A Lindskog

Publications and source records attributed to A Lindskog.

4 recordsLinked to original sources
PubMed1984

A comparison between different high volume sampling systems for collecting ambient airborne particles for mutagenicity testing and for analysis of organic compounds.

Samples of urban air were collected simultaneously using different sampling systems, including electrostatic precipitation (ESP) and high volume filtration (HVF) on various filters for particle sampling and absorption on activated carbon and organic polymers for sampling of volatiles. Acetone extracts of the samples were analyzed for polycyclic aromatic hydrocarbons (PAH) and tested for mutagenicity with the Ames Salmonella/microsome assay. The results show that the concentrations of PAH found in the various particle-samples were in good agreement, whereas the mutagenic activity of these samples showed large variations. The highest mutagenic activity was found in the samples collected by ESP and on the teflon-coated glassfibre filters, whereas samples collected by high volume filtration with size-fractionation showed the lowest mutagenic activity. We do not know whether the higher activity in samples from the teflon-coated filters compared to those from ordinary glassfibre filters represent filter artifacts or if it represents a more pronounced degradation of mutagenic compounds on the non-coated glassfibre filters. Extracts from filter blanks seemed to interfere with the expression of the mutagenic activity of the positive controls, benzo[a]pyrene and nitropyrene. When sampling volatile compounds, two organic polymers, polyurethane (PUR) and XAD-2, were found suitable for collecting PAH, whereas no PAH could be detected in extracts from the activated carbon. The XAD-2 adsorbent was the most effective for sampling bicyclic PAH. None of the adsorbents yielded extracts well suited for mutagenicity testing, since blank extracts were toxic to the test bacteria. Some extracts of the PUR blanks were weakly mutagenic as well. More emphasis should be placed upon developing more efficient and unreactive adsorbents and on the adaptation of such adsorbents in samplers suited for routine use.

Air Pollutants↗
PubMed1983

Transformation of polycyclic aromatic hydrocarbons during sampling.

Individual PAH are shown to undergo chemical transformation when exposed to gases such as NO2, O3 and SO3. The possibility of artifact formation during sampling in stacks and in ambient air is discussed. PAH on soot, formed in a smoke gas generator, and exposed to NO chi and SO chi in a thermostated oven were degraded as a result of the sampling technique. Addition of NO2 (1 ppm) or gaseous HNO3 (120 ppb) during ambient air sampling caused degradation of individual PAH on particles and formation of the corresponding mononitro-PAH. Addition of 200 ppb O3 or 100 ppb gaseous HNO2 had no detectable effect. Thus, artifact formation can occur as a result of the presence of NO2, HNO3, or SO chi both in stack gas sampling and in sampling of PAH on particles in ambient air.

Air Pollutants↗