Objective: To investigate the prevalence of nasal and ocular symptoms and nasal signs in foundry workers exposed to monoisocyanates using the Hot Box method.
Methods: Forty-three foundry workers and 69 referents completed questionnaires and were examined by a rhinologist. Exposure to isocyanic acid, methyl isocyanate, formaldehyde, and total dust was measured.
Results: Nasal symptoms and signs were associated with exposure, and dose–response relationships between nasal symptoms and exposure to isocyanic acid, methyl isocyanate, and formaldehyde were observed. Dry nasal mucosa was more prevalent in exposed workers than in referents. These findings were not substantially affected by the exclusion of asthmatic and allergic individuals, smokers, or females.
Conclusions: An increased prevalence of nasal symptoms and signs was observed among exposed workers, suggesting an association with the foundry environment involving monoisocyanates and other airway irritants, such as formaldehyde and dust.
From the Department of Occupational and Environmental Medicine (Drs Löfstedt, Westberg, and Seldén, Ms Bryngelsson and Ms Ngo) and Department of Otorhinolaryngology (Dr Rudblad), Örebro University Hospital, Örebro, Sweden; Division of Occupational Medicine, Department of Public Health Sciences, Karolinska Institutet (Drs Löfstedt and Svartengren) and Department of Occupational and Environmental Health, Stockholm County Council (Dr Svartengren), Stockholm, Sweden; and Section of Biostatistics and Epidemic Modelling, Department of Epidemiology, Swedish Institute for Infectious Disease Control, Tomtebodavägen, Solna, Sweden (Ms Ngo).
Address correspondence to: Håkan Löfstedt, MD, Department of Occupational and Environmental Medicine, Örebro University Hospital, SE-701 85 Örebro, Sweden; E-mail: firstname.lastname@example.org.
The study was financed by VINNOVA (Swedish Governmental Agency for Innovation Systems) with grant nos 2001-03393 and 2001-03954.