The role of endotoxin in grain dust-induced lung disease.

Abstract

To identify the role of endotoxin in grain dust-induced lung disease, we conducted a population-based, cross-sectional investigation among grain handlers and postal workers. The study subjects were selected by randomly sampling all grain facilities and post offices within 100 miles of Iowa City. Our study population consisted of 410 grain workers and 201 postal workers. Grain workers were found to be exposed to higher concentrations of airborne dust (p = 0.0001) and endotoxin (p = 0.0001) when compared with postal workers. Grain workers had a significantly higher prevalence of work-related (cough, phlegm, wheezing, chest tightness, and dyspnea) and chronic (usual cough or phlegm production) respiratory symptoms than postal workers. Moreover, after controlling for age, gender, and cigarette smoking status, work-related respiratory symptoms were strongly associated with the concentration of endotoxin in the bioaerosol in the work setting. The concentration of total dust in the bioaerosol was marginally related to these respiratory problems. After controlling for age, gender, and cigarette smoking status, grain workers were found to have reduced spirometric measures of airflow (FEV1, FEV1/FVC, and FEF25-75) and enhanced airway reactivity to inhaled histamine when compared with postal workers. Although the total dust concentration in the work environment appeared to have little effect on these measures of airflow obstruction, higher concentrations of endotoxin in the bioaerosol were associated with diminished measures of airflow and enhanced bronchial reactivity. Our results indicate that the concentration of endotoxin in the bioaerosol may be particularly important in the development of grain dust-induced lung disease.

MD-2–Dependent Pulmonary Immune Responses to Inhaled Lipooligosaccharides

“…Inflammatory responses to inhaled endotoxin have been studied in both humans (2,(32)(33)(34) and mice (35)(36)(37)(38). In general, inhalation or nasal aspiration of endotoxin by mice induces similar host responses and changes (35,39), and these reflect human airway responsiveness (33).…”

“…When bacteria and bacterial components invade the host, they stimulate a variety of specialized host cells, including epithelial cells, monocytes, macrophages, neutrophils, and endothelial cells, as part of the acute inflammatory response (1). These responses are crucial for host defense but, in excess, can be very harmful causing local and multi-system derangements, including pulmonary inflammation (2), shock, and occasionally death (3).…”

Spatial variability in airborne bacterial communities across land-use types and their relationship to the bacterial communities of potential source environments

“…These airborne bacteria may have important impacts on human health, serving directly as human pathogens or triggering allergic reactions (Schwartz et al, 1995;Hussman, 1996). In addition, bacterial pathogens of agricultural crops and livestock can be transported through the atmosphere (Romantschuk and Bamford, 1986;Gonzalez et al, 2000).…”

Prevalence of respiratory symptoms and disorders among rice mill workers in India

“…Occupational exposure to organic dust and endotoxin may cause various respiratory diseases, including asthma, allergic alveolitis, chronic bronchitis, toxic pneumonitis [18][19][20][21] as well as acute and/or chronic lung function impairment [22][23][24][25]. Several cross-sectional studies in different work environments were conducted to assess the relationship between occupational exposure to bio-aerosols and over-shift changes in lung function.…”