Asthma caused by tea dust

  • Food industry
Incidence: rare - a few cases have been described. The mechanism remains to be established, but may be due to a type of irritation. There are no reports that IgE is involved. Smoking has sometimes been desribed as a co-factor.
The cause is the leaf dust and debris from dry tea and a type of packaging material used when the tea is put into sacks. Of the many components of the tea leaf, epigallocatechine gallate (EGCg;mw:458 daltons) appears to be the most allergenic.
Rhinitis, cough, sporadic coryza, breathing difficulty and asthma.
Diagnostic methods
Skin tests are negative. RAST/CAP RAST with tea.
Bronchial provocation test (in hospital) with tealeaf dust is positive with both an immediate and a delayed reaction.
Both skin prick tests and bronchial provocation tests with EGCg give rise to an immediate reaction.


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As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.