The major findings of this study are summarized below:
• No evidence of serious health effects was found to be associated with exposure to any of the theatrical effects evaluated in this study.
• Peak exposures to elevated localized air concentrations following a release of glycol smoke are associated with increased reporting of respiratory, throat, and nasal symptoms, and findings of vocal cord inflammation.
• Elevated exposures to mineral oil haze are associated with increased reporting of throat symptoms.
• No health effects were associated with the current use of pyrotechnic effects in any of the productions included in the study.
• There was no evidence of an additive or multiplicative increase in effect from exposure to more than one of the types of theatrical effects evaluated in this study.
• Other factors besides theatrical effects were also found to be associated with increased symptom reporting. These factors include perceived levels of stress (at work and away from work), performance schedule, and physical demand of the role(s) played.
• Based on the observed association between increased signs and symptoms of respiratory irritant effects and exposure to elevated levels of glycols and mineral oil, it is recommended that exposures to these materials by Actors performing in musical productions not exceed peak or ceiling concentrations of 40 mg/m3 for glycols and 25mg/m3 for mineral oil. Time-weighted average exposures to mineral oil should be kept below 5 mg/m3. Based on the results of this study, no change in the current use of pyrotechnics is necessary. As long as peak exposures are avoided, health, vocal abilities, and careers of Actors should not be harmed.