The Effect of Wood Aerosols and Bioaerosols on the Respiratory Systems of Wood Manufacturing Industry Workers in Golestan Province.

BACKGROUND: Occupational exposure to dust leads to acute and chronic respiratory diseases, occupational asthma, and depressed lung function. In the light of a lack of comprehensive studies on the exposure of Iranian workers to wood dusts, the objective of this study was to monitor the occupational exposure to wood dust and bioaerosol, and their correlation with the lung function parameters in chipboard manufacturing industry workers. MATERIALS AND METHODS: A cross-sectional study was conducted on chipboard workers in Golestan Province; a total of 150 men (100 exposed cases and 50 controls) were assessed. Workers were monitored for inhalable wood dust and lung function parameters, i.e., FVC, FEV1, FEV1/FVC, and FEF25-75%. The workers' exposure to bioaerosols was measured using a bacterial sampler; a total of 68 area samples were collected. The analysis was performed using the Mann-Whitney, Kruskal-Wallis, and regression statistical tests. RESULTS: The geometric mean value and geometric standard deviation of inhalable wood dust for the exposed and control groups were 19 ± 2.00 mg/m3 and 0.008 ± 0.001 mg/m3, respectively. A statistically significant correlation was observed between the lung parameters and cumulative exposure to inhalable wood dust, whereas a statistically significant correlation was not observed between the lung parameters and bioaerosol exposure. However, the exposure of Iranian workers to bioaerosols was higher, compared to their foreign coworkers. CONCLUSION: Considering the high level of exposure among workers in this study along with their lung function results, long-term exposure to wood dust may be detrimental to the workers' health and steps to limit their exposure should be considered seriously.

Work-related exacerbation of asthma among adults treated by pulmonary specialists.

The most common chronic occupational lung disease is occupational asthma. This study aimed to assess the prevalence of work-related respiratory symptoms (WRS) in asthmatic adults at pulmonary clinics. A cross-sectional study was performed. Current employed subjects were subdivided into 2 groups by WRS status according to questionnaire mainly based on one developed by the National Institute for Occupational Safety and Health (NIOSH). Subjects' occupation and workplace exposures were evaluated by asthma-specific job exposure matrix (JEM). Thirty-nine of 179 current employed asthmatics had WRS. Subjects with WRS were more likely to have self-reported allergy and exposure to low-molecular-weight antigens (prevalence ratio [PR]: 2.7). The 2 most frequent occupational classes for asthmatics with WRS were trades, transport and equipment operators, and processing and manufacturing. Self-reported allergy, high-risk exposures, and occupations unique to processing, manufacturing, and utilities were estimated to be risk factors of WRS.

Effect of Ventilation on Occupational Exposure to Airborne Biological Contaminants in an Isolation Room.

BACKGROUND: Airborne pathogens play an important role in a hospital air quality. Respiratory infections are the most common occupational disease among the health care staff. The aim of this study was to determine the effect of ventilation system parameters and patient bed arrangements on concentration of airborne pathogens in indoor air of an isolation room. MATERIALS AND METHODS: A single-bed room was considered in which a patient diagnosed with tuberculosis had been admitted. Five different ventilation types, each at four different capacities were installed in the room while two different locations for the patient's bed were assessed. A direct-impact sampling method (blood agar plate) was used in order to determine the intensity of the bio-aerosols in indoor air of the isolation room. RESULTS: The results showed that when the air was supplied through a circular vent located on the northern wall and the vented air was exhausted via a linear vent located on the southern wall, the average concentration of the bio-aerosols in the air, (with 12 air changes per hour) was reduced to 25 colonies per cubic meter (cfu/m(3)) (in the range of 25-88 cfu/m(3) and a 95 percent confidence interval). In accordance with the analysis applied upon the two different locations of the bed, no significant difference was observed (P>0.05). CONCLUSION: Installation of ventilation systems as determined by the study is recommended for tuberculosis isolation rooms.