Prevalence and predictors of work related respiratory symptoms in workers exposed to organic dusts.

Abstract

Objectives-The aims of this study were to document the prevalence of work related upper and lower respiratory tract symptoms in workers exposed to organic dusts and to identify variables predictive of their occurrence. Methods-A cross sectional survey with an administered questionnaire (a previously validated adaptation of the Medical Research Council (MRC) respiratory questionnaire) was performed. Symptoms were classified as work related by their periodicity. Demographic data, smoking habits, and occupational histories were recorded. Personal exposures to dust and endotoxin were measured and individual subjects ascribed an exposure value specific to occupation, site and industry. Cox's regression techniques were used to identify variables predictive of work related upper and lower respiratory tract symptoms. Information was stored using Dbase 3 and analysed with SPSS. Results-1032 Workers (93 % of the target population) were studied in nine diVerent industries. The highest prevalences of work related lower respiratory tract symptoms (38.1 %), upper respiratory tract symptoms (45.2 %), and chronic bronchitis (15.5 %) were found among poultry handlers. White workers were significantly more likely to complain of upper and lower respiratory tract symptoms. An individual in the swine confinement industry had a symptom complex compatible with byssinosis. Increasing current personal exposures to dust or endotoxin were found to be predictive of upper and lower respiratory tract symptoms, chronic bronchitis, and byssinosis. In a univariate analysis a relation between current exposures and the organic dust toxic syndrome was found. Present smoking and previously documented respiratory tract illness were significantly predictive of work related lower respiratory tract symptoms. Women were more likely to report work related upper respiratory tract symptoms. Conclusions-People exposed to organic dusts may have a high prevalence of work related respiratory tract symptoms which are related to dust exposures and smoking habits. Action should be taken to reduce exposures to dust and endotoxin and stopping smoking should be promoted among workers exposed to organic dusts to reduce morbidity. (Occup Environ Med 1998;55:668-672)

Pet- and pollen-induced upper airway symptoms in farmers and in nonfarmers

“…These findings are in agreement with previous studies pointing to a low prevalence of UAS, which are thought to be allergic [14][15][16], and to a high prevalence of farm work-induced UAS in animal farmers [15,16,19,20]. This study extends the findings of previous studies by confirming the allergic nature of these symptoms, since skin tests were also carried out.…”

“…Table 5. -Adjusted odds ratios (95% confidence interval) for upper airway symptoms (UAS) with respect to farming characteristics been shown to correlate with high exposure to dust, endotoxin and fungal spores [19,20]. Therefore, it seems probable that work-induced UAS in farmers result from exposure to many different inducers.…”

The variability of bacterial aerosol in poultry houses depending on selected factors

“…Other airborne bacteria in breeding facilities may be defined as environmental bacteria; they have not been mentioned in the quoted regulation of the Minister of Health, and it is hardly probable that they could induce diseases. However, we should remember that Gram-negative bacteria even from environmental group may be a source of endotoxins inducing immunotoxic reactions in people [8,[14][15][16]18]. The number of samples collected in our study was limited; therefore, it would not be reasonable to generalize our conclusions about differences in bioaerosol concentrations in poultry houses.…”

“…The bacterial aerosol consists of staphylococci, streptococci, numerous Gram-positive and Gram-negative rod-shaped bacteria, including Bacillus genus [4,5,[7][8][9][10][11][12][13]. Both live cells and their components (endotoxins in case of Gramnegative bacteria) may induce in poultry breeding employees a number of symptoms and diseases, mainly within the respiratory tract, as well as the toxic syndrome induced by endotoxins found in the organic dust [14][15][16][17][18][19][20][21]. The degree of hazardousness of airborne bioaerosol particles in breeding facilities depends not only on the pathogenicity of microorganisms or toxicity of their products but also on the particle size which determines their ability to penetrate the human respiratory tract.…”

Technical note: concentration and composition of airborne aerobic bacteria inside an enclosed rabbit shed

“…Despite the lack of evidence for a correlation between quantity of airborne aerobic bacteria and disease incidence, there has been substantial research suggesting that increasing airborne aerobic bacterial load can impair immunity, retard growth and lower the productivity of animals (Simpson et al, 1998). In the current study, the concentration of airborne aerobic bacteria inside the enclosed-type rabbit shed was calculated to be between 2.11-6.36×10 4 colony forming unit (CFU)/m 3 .…”