EXPOSURE TO FINE AIRBORNE FIBROUS DUST AMONGST PROCESSORS OF PARA-ARAMID

Citation
Jw. Cherrie et al., EXPOSURE TO FINE AIRBORNE FIBROUS DUST AMONGST PROCESSORS OF PARA-ARAMID, The Annals of occupational hygiene, 39(4), 1995, pp. 403
Citations number
19
Categorie Soggetti
Toxicology,"Public, Environmental & Occupation Heath
ISSN journal
00034878
Volume
39
Issue
4
Year of publication
1995
Database
ISI
SICI code
0003-4878(1995)39:4<403:ETFAFD>2.0.ZU;2-M
Abstract
Laboratory studies with animals exposed to high concentrations of fine fibrous dust (fibrils) derived from pai a-aramid fibres suggest that it may cause lung damage. Based on the information from such studies t here is an initiative in the U.K. to regulate workplace exposure. Para -aramid fibres are used in textiles, friction products, composite mate rials and other applications, but little is known about the extent or intensity of fibre dust exposure during these manufacturing operations . A survey has been undertaken in a selection of manufacturers of pala -aramid containing products to assess their 8-h time-weighted average exposure to respirable fibrils. Concentrations were measured using the membrane filter technique with analysis by phase-contrast microscopy. Measurements of airborne fibril size were also made by scanning elect ron microscopy. Geometric mean concentrations for different jobs were generally low, ranging from 0.005 to 0.4 fibres ml(-1). Assuming a log -normal distribution, less than 1% of the exposure levels would be exp ected to exceed 0.5 fibres ml(-1) and about 0.002% would be above 2 fi bres ml(-1). Analysis of a selection of samples by fluorescence micros copy suggests that most of the fibrils in the majority of sites survey ed were para-aramid. At some sites a significant proportion of asbesto s fibres were also found.