Analysis of organophosphorus flame retardants in submicron atmospheric particulate matter (PM1)

This study is aimed to determine the occurrence of organophosphorus flame retardants (OPFRs) in atmospheric particulate matter with an aerodynamic diameter of less than 1 mu m (PM1). The analytical method is based on Soxhlet extraction and a clean-up step with Florisil solid phase extraction (SPE). Detection and quantification was performed by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Validation included laboratory and field blank tests as well as the determination of the method efficiency using spiked quartz filters with 20 ng and 200 ng of OPFR mixture. Ambient air PM samples with particle concentrations between 4 and 26 mu g/m(3) were collected at an urban background site in Barcelona under contrasting meteorological conditions in order to study occurrence of OPFRs in relation to particle loads. In these samples, OPFRs were detected at levels ranging from a few pg/m(3) to 1200 pg/m(3) and substantial correlations were observed between the levels of certain OPFRs and atmospheric particle loadings. The presence of individual compounds in pg/m(3) concentrations levels in the sub-micron PM mode (PM1) at an urban background site indicates a considerable exposure to these compounds for the human population in this area. This is the first study to determine OPFR in PM1.