title: Linear and cyclic methylsiloxanes in air by concurrent solvent recondensation-large volume injection-gas chromatography-mass spectrometry.
abstract: In the present work, a simple and fast method for the analysis of linear and cyclic methylsiloxanes in ambient air based on active sampling combined with gas chromatography - mass spectrometry (GC-MS) was developed. The retention efficiency of five sampling sorbents (activated coconut charcoal, Carbopack B, Cromosorb 102, Cromosorb 106 and Isolute ENV+) was evaluated and Isolute ENV+ was found to be the most effective. A volume of 2700 L of air can be sampled without significant losses of the most volatile methylsiloxanes. To improve the sensitivity of the GC-MS method, concurrent solvent recondensation - large volume injection (CSR-LVI), using volumes up to 30 µl of sample extract, is proposed and limits of quantification down to 0.03-0.45 ng m(-3), good linearity (r>0.999) and precision (RSD %<9%) were obtained. The developed method was applied to the analysis of ambient air. Concentrations of linear and cyclic methylsiloxanes in indoor air ranging from 3.9 to 319 ng m(-3) and between 48 and 292668 ng m(-3), were obtained, respectively, while levels from 6 to 22 ng m(-3) for linear and between 2.2 and 439 ng m(-3) for cyclic methylsiloxanes in outdoor air from Barcelona (Spain), were found.
authors.affiliation: Analytical Chemistry Department, University of Barcelona, Avda. Diagonal 645, 08028 Barcelona, Spain.
authors.forename: E Y
authors.initials: EY
authors.lastname: Companioni-Damas
authors.forename: F J
authors.initials: FJ
authors.lastname: Santos
authors.forename: M T
authors.initials: MT
authors.lastname: Galceran
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D004784:Environmental Monitoring; D017022:Flow Injection Analysis / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D012833:Siloxanes / Q000032:analysis*; D012997:Solvents / Q000737:chemistry*; D013030:Spain
chemical_list: D000393:Air Pollutants; D012833:Siloxanes; D012997:Solvents
keywords: Air analysis; Gas chromatography–mass spectrometry; Indoor and outdoor air; Large volume injection; Linear and cyclic methylsiloxanes