Significance and Use
Environmental tobacco smoke consists of both vapor- and particle-phase components. Due to the nature of vapor and particulate phases, they rarely correlate well, and an accurate assessment of ETS levels in indoor air requires determining good tracers of both phases. Among the attributes of an ideal ETS tracer, one critical characteristic is that the tracer should “remain in a fairly consistent ratio to the individual contaminant of interest or category of contaminants of interest (for example, suspended particulates) under a range of environmental conditions...” (2). The UVPM and FPM fulfill this requirement, staying in a constant ratio to RSP from tobacco smoke under a variety of ventilation conditions and sampling durations. Solanesol (a C45 isoprenoid alcohol specific to tobacco), determined in accordance with Test Method D6271, is an ETS tracer or marker that also meets this requirement. In contrast, nicotine (a component of the ETS vapor phase) does not remain in a consistent ratio to ETS-PM (3).
To be able to quantify the contribution of ETS to RSP is important because RSP is not specific to tobacco smoke. The RSP are a necessary indicator of overall air quality; the Occupational Safety and Health Administration (OSHA) has previously set a PEL (permissible exposure level) for respirable dust in the workplace of 5000 μg/m3. However, the RSP emanate from numerous sources (4) and have been shown to be an inappropriate tracer of ETS (5-13). In the test methods described herein, UVPM and FPM are used as more selective markers to estimate more accurately the contribution of ETS to RSP (5-7, 9-18). Of the available ETS particulate phase markers (UVPM, FPM, and solanesol), all are currently used and relied upon in investigations of indoor air quality, although UVPM and FPM can overestimate the contribution of tobacco smoke to RSP due to potential interference from nontobacco combustion sources. Solanesol, because it is tobacco-specific and ETS particle phase-specific, may be the best indicator of the ETS particulate phase contribution to RSP (9-13, 19-21). Refer to Test Method D6271 for the protocol on determining solanesol.
Scope
1.1 These test methods pertain to the sampling/analysis of respirable suspended particles (RSP) and the estimation of the RSP fraction attributable to environmental tobacco smoke (ETS). These test methods are based on collection of total RSP on a membrane filter, extracting the collected material in methanol, and measuring total ultraviolet absorbance or fluorescence, or both, of this extract. The corresponding methods of estimation are termed ultraviolet particulate matter (UVPM) and fluorescent particulate matter (FPM), respectively.
1.2 These test methods are compatible with, but do not require the determination of solanesol, which is also used to estimate the contribution of ETS to RSP (see Test Method D6271).
1.3 The sampling components consist of a preweighed, 1.0-μm pore size polytetrafluoroethylene (PTFE) membrane filter in a filter cassette connected on the inlet end to a particle size separating device and, on the outlet end, to a sampling pump. These test methods are applicable to personal and area sampling.
1.4 These test methods are limited in sample duration only by the capacity of the membrane filter (about 2000 μg). These test methods have been evaluated up to a 24-h sample duration with a minimum sample duration of at least 1 h.
1.5 Limits of detection (LOD) and quantitation (LOQ) for the UVPM test method at a sampling rate of 2 L/min are, respectively, 2.5 μg/m3 and 8.3 μg/m3 for a 1-h sample duration and 0.3 μg/m3 and 1.0 μg/m3 for an 8-h sample duration. The LOD and LOQ for the FPM test method at a sampling rate of 2 L/min are, respectively, 1.4 μg/m3 and 4.7 μg/m3 for a 1-h sample duration and 0.2 μg/m3 and 0.6 μg/m3 for an 8-h sample duration.
1.6 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary information is given in 13.6.
