Respiratory symptoms of exposure to substances in the workplace among Bulgarian dentists

Objectives Dentists are exposed to a variety of airborne chemicals that can act as irritants and sensitizers and may give rise to work-related respiratory symptoms. The aim of this study was to estimate the prevalence of respiratory symptoms of exposure to substances in the workplace and associated risk factors in Bulgarian dentists. Methods A cross-sectional study was performed among Bulgarian dentists by using a self-report questionnaire. A direct acyclic graph (DAG) was elaborated to illustrate the direct and indirect causal pathways between exposure to irritants and/or allergens from dental environment and work-related respiratory symptoms among dentists. Multiple logistic regression analysis was conducted in order to investigate the relationship between sex, work experience, daily exposure to chemicals from dental environment, history of atopic disorder and work-related respiratory symptoms. Results A total of 4675 dentists completed the questionnaire (response rate 48.1%). The prevalence of self-reported work-related respiratory symptoms was 20.7%. The most common repeated causes of respiratory reactions were disinfectants (65.7%) and materials based on acrylic resins (29.7%). Factors associated with work-related respiratory symptoms are personal history of asthma (odds ratio (OR) 2.50, 95% confidence interval [CI]: 1.71-3.64), work experience >20 years (OR 2.17, 95% CI: 1.74-2.70) and female gender (OR 2.14, 95% CI: 1.81-2.56). Conclusion Work-related respiratory symptoms are frequent among dentists and indicate a need for efforts to establish effective programmes and techniques of reducing or eliminating direct exposure to airborne chemicals in the dental environment.