A meta-analysis of airborne asbestos fiber concentrations from work with or around asbestos-containing floor tile

ABSTRACT

In this meta-analysis, exposures to airborne asbestos during work with or around floor tiles were characterized according to several variables: study, sample type, activity, and task. Personal breathing zone, bystander, and area sample exposure concentrations were differentiated and compared against current occupational exposure limits to asbestos. In total, 22 studies, including 804 personal, 57 bystander, and 295 area samples, were included in the analysis. The arithmetic mean airborne fiber concentrations were 0.05, 0.02, and 0.01 f/cm³ for personal, bystander, and area samples, respectively. Arithmetic mean time-weighted-average fiber concentrations over an 8-h working day were 0.02 and 0.01 f/cm³ for personal and bystander samples, respectively. Phase contrast microscopy (PCM) personal airborne fiber concentrations were highest for maintenance activities, followed by removal and installation. Tasks that involved buffing or burnishing, scoring or snapping, and scraping or lifting had the highest personal PCM concentrations, while stripping floor tile and removing it with chemical solvent had the lowest concentrations. Exposures associated with handling asbestos floor tiles, under working conditions normally encountered, do not generally produce airborne concentrations at levels that exceed the current OSHA PEL nor do they appear to approach the threshold cumulative asbestos dose concentrations that have been previously associated with an increased risk of asbestos-related disease.

KEYWORDS:

• Asbestos
• floor tile
• exposure
• removal
• installation
• trafficking
• maintenance
• risk

Acknowledgments

The authors extend their gratitude to Brent Finley for his valuable input. They also thank Andrew Patton, Ellen Donovan, and Matt Grespin for assisting with the research for this article.

Disclosure statement

The research supporting this analysis and the time needed to write the  paper  were  funded  entirely  by  Cardno ChemRisk. Only the authors and those listed in the acknowledgments provided editorial  comments  prior to submission to the journal. Two of the authors have  served  and  may continue  to  serve  as  expert  witnesses regarding  the historical exposures  to asbestos.

Supplementary material

Supplemental data can be accessed here.