A minimum of 5×103 events were acquired in list mode and analyzed with Cellquest software (Becton Dickinson).
The mass spectrometer was operated in a data-dependent MS/MS mode and analyzed with one full m/z range (400 2000) each.
MS analysis was carried out with the MALDI-TOF mass spectrometer Reflex III (Bruker-Daltonics, Billerica, MA) in the positive ion reflector mode and analyzed by the peaklist-generating software FlexControl™ 2.2.
From April 1997 through March 1998, samples of inhalable particles were collected, separated into fine and coarse particulate mode, and analyzed for black carbon and tracer elements.
In Calgary, scans were done on a Hologic QDR 4500 W® scanner in whole-body mode and analyzed with software version 11.2.1 (Hologic®, Inc., Bedford, MA, USA).
The spectrum was obtained with an accelerating voltage of 20 kV in linear mode and analyzed within an m/ z range 2000 20 000 Da.
In Edmonton, scans were done on a Lunar Prodigy® scanner in either standard mode or thick mode and analyzed with enCORE Software 6.70.01 before November 2004 and 8.60 after November 2004 (Lunar® General Electric Medical Systems, Madison, WI, USA).
Masses were scanned from 100 to 1100 amu at approximately 0.4 scan s-1, and data were collected from m/z 90 to 1000 in continuum mode, and analyzed by Micromass MassLynx 4.1 software (Waters Co., USA).
Lipid extract in methanol/chloroform (2 1, v/v) was injected into a Hewett-Packard 6890 GC in a splitless mode and analyzed with a 15 m DB-1701 column (0.25 mm i.d, 0.25 µm film thickness; J & W Scientific).
