Reference

BOHRF Original Authors' Main Conclusions

The original authors' main conclusions are taken from Abstract, Results and Discussion. They are decided upon by the authors of the BOHRF occupational asthma guidelines and form part of the guidelines.

7/12 cases, Toluene di-isocyanate (TDI) asthma was documented by a positive inhalation challenge to low levels of TDI. 6/7 TDI reactors had persistent respiratory symptoms and required daily treatment even though they had been removed from exposure for as long as 12 years (mean 4.5 years). 4/6 of these TDI reactors had dual bronchospasm and 2/6 had late bronchospasm to less than 20 ppb TDI - all had a positive methacholine or cold air challenge prior to study. The one TDI reactor with a negative methacholine challenge had a positive (immediate) bronchospastic response to a TDI challenge performed one week after removal from exposure. 5/12 had negative TDI challenge, two of whom had persistent respiratory symptoms and positive methacholine challenges at time of TDI inhalation testing. Conclude that respiratory symptoms may persist following long-term removal from occupational exposure to TDI and are associated with non-specific bronchial hyper-reactivity. The TDI sensitivity may also persist for a long time even in the absence of any additional occupational exposure.

BOHRF Associated Evidence Statements

The BOHRF occupational asthma guidelines state that this reference is associated with the following evidence statements