Korean J Occup Environ Med.  2004 Jun;16(2):191-199.

Prevalence of Occupational Asthma in TDI-Exposed Workers

• Kim HR
• Kim CW
• Hong YC
• Chun HJ
• Kim CN
• Kim HS
• Lee JN
• Shin JY
• Koh DH
• Roh J

Abstract

OBJECTIVES
This study was carried out to estimate the prevalence of isocyanate-induced occupational asthma in toluene diisocyanate (TDI) exposed workers.
METHODS
We examined 170 workers who had been directly exposed to TDI through a medical questionnaire, physical examination, and pulmonary function test. Based on screening examination, workers with suspected occupational asthma were selected for further evaluation such as methacholine and TDI challenge tests.
RESULTS
Eleven (6.9%) among 170 workers complained of symptoms of occupational asthma, and 7 among these 11 symptomatic workers showed positive responses to the methacholine challenge test (4.1%). One spray painter was confirmed as having the TDI induced occupational asthma following a positive response to TDI challenge test.
CONCLUSIONS
The prevalence of TDI-induced asthma was at 0.58% was lower than that for former studies (2-20%). Improved workplace environment, lower level of TDI exposure compared to the past, and the healthy workers effect may have contributed to this low rate of asthma prevalence in workers with TDI exposure.

Keyword

Occupational asthma; TDI; Prevalence

MeSH Terms

Asthma
Asthma, Occupational*
Mass Screening
Methacholine Chloride
Physical Examination
Prevalence*
Questionnaires
Respiratory Function Tests
Toluene 2,4-Diisocyanate
Methacholine Chloride
Toluene 2,4-Diisocyanate