Respiratory symptoms and lung function in foundry workers exposed to low molecular weight isocyanates

Abstract

An increased prevalence of ocular and respiratory symptoms, as well as a small decrease in lung function over shift, was observed among exposed workers. No associations with exposure to monoisocyanates and formaldehyde were seen, thus suggesting that other irritants in the foundry environment might be the cause. The effects seemed to be small and not clinically relevant on an individual level. Further studies using a follow-up design may be warranted.

Nasal and Ocular Effects in Foundry Workers Using the Hot Box Method

“…Seventytwo percent of all the subjects in this study also participated in the initial study 4 years earlier. 11 The geometric means (GM) of the measured exposures to ICA, MIC, formaldehyde, and total dust were 12, 3.1, 37, and 360 μg/m 3 , respectively ( Table 1). Twenty of 42 individuals were exposed to quantities greater than the median of both ICA and MIC and classified as highly exposed to both species.…”

“…Nevertheless, an unusually high prevalence of nasal symptoms was noted in both the exposed group and the referents. 11 Nasal symptoms are also common among workers not subject to industrial exposure. For example, the prevalence of nasal symptoms in the week prior to testing in a sample of primary school personnel (50%) is intermediate between that observed in the exposed and referent groups in this study.…”

“…11 On the day of the nasal examination, subjects were asked to complete a short additional questionnaire regarding their nasal and ocular symptoms during the week preceding the examination. The questions concerning nasal symptoms had been used in an earlier study.…”

“…While no data on the toxicity of ICA in humans or animals have been reported, 10 the respiratory and ocular effects associated with exposure to MIC and formaldehyde have been summarized. 11 Occupational rhinitis is two to four times more prevalent than occupational asthma, and various studies have found that it precedes the development of asthma in 20% to 78% of affected subjects. 12 In a study of painters exposed to toluene diisocyanate, 42% were found to be suffering from occupational rhinitis.…”

“…17 A previous study of our group did not indicate an association between exposure to ICA, MIC, or formaldehyde and reduced lung function, but nasal symptoms were reported by significant numbers of both the exposed workers and the referents. 11 Because of these results, nasal examination was added in the cross-sectional study described in this article. The study is part of a longitudinal study of foundry workers exposed to fumes and gases resulting from the Hot Box method; the broader study had been running for 4 years at the time of this study.…”