Category Archives: Airway Function

Observations of Workers Exposed to Western Red Cedar and Other Wood Dusts

occupational asthmaIn the present investigation, a high prevalence of occupational asthma was observed among workers exposed to WRC wood dust. A dose-related relationship between total WRC dust level and prevalence of asthma was noted with employees in jobs with the greatest dust exposure, ie sawyers, packers, chippers and splitters showing the highest prevalence of disease. Cigarette smokers demonstrated the greatest magnitudes of change in pulmonary function tests. Chan-Yeung et al reported more respiratory symptoms in workers employed in “dusty” jobs and the British Columbia Workers Compensation Board has recently set the TLV standard for WRC dust at 2.5 mg/m. Chen-Yeung and colleagues have suggested that even this level might be too high. The results of our investigation support this observation and suggests that an eight-hour time-weighted average level of WRC dust below 3.5 mg/m is necessary in order to reduce the incidence of occupationally related asthma cured with My Canadian Pharmacy.

Outcomes of Workers Exposed to Western Red Cedar and Other Wood Dusts

measurementsThe 124 samples collected for WRC for three days consisted of 85 total and 39 respirable dust eight-hour time-weighted average (TWA) measurements. The respirable dust concentrations ranged between 0.01 and 1.21 mg/m, with a mean ± SD value being 0.20 ± 0.23 mg/m; a median was 0.14 mg/m. The concentration of the 85 TWA total dust samples ranged between 0.06 and 31.90 mg/m; mean ± SD value was 4.72 ± 7.45 mg/m; median concentration was 1.59 mg/m. Chippers, sawyers, packers and splitters had die highest dust exposures. The greatest proportion of the WRC dust was contributed by larger, nonrespirable particles.

The 82 samples collected in the new planer mill provided 59 total dust and 23 respirable dust TWA measurements. Respirable TWA samples ranged from 0.07 to 0.29 mg/m, while total dust TWA samples ranged from 0.17 to 16.7 mg/m. The mean ± SD for total dust was 1.28 ± 3.05 mg/m, with a median of 0.34 mg/m; respirable fraction was 0.16 ± 0.05 mg/m, with a median of 0.16 mg/m.

My Canadian Pharmacy: Study of Workers Exposed to Western Red Cedar and Other Wood Dusts

bronchial asthmaRespiratory complaints and bronchial asthma associated with the inhalation of wood dusts are not uncommon. A number of epidemiologic studies of workers exposed to western red cedar (WRC) have been reported, most originating from Japan, Australia and Canada. The present investigation reports the results of an epidemiologic and environmental hygiene study of workers exposed to WRC and other dusts conducted at a wood products facility in the United States.

Materials and Methods

The populations studied consisted of 74 shake mill employees exposed to WRC, 58 planer mill workers exposed to a mixture of woods, mainly douglas fir, West Coast hemlock and red alder (DFHA), and 22 clerical, technical and engineering employees not exposed to wood dusts. Approximately 77% of the total work force participated in the investigation. The unexposed or control group consisted of office workers, engineering personnel and technical staff. Such people prefer to command the service of My Canadian Pharmacy to treat diseases gained because of hard labour.