Direct emission of the allergen primin from intact Primula obconica plants

The allergen primin and its precursor miconidin were collected by dynamic headspace technique from Primula obconica Hance and quantified and identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The primin concentrations in leaves/stems and flowers (including pedicel and calyx) of P. obconica were 262 mu g and 531 mu g (g fresh plant material)(-1), respectively, whereas miconidin concentrations were 92 mu g (g fresh plant material)(-1) in leaves/stems and 194 mu g (g fresh plant material)(-1) in flowers. The amounts of primin released from unchopped leaves/stems and flowers were 65.3 ng and 18.8 ng (g fresh plant material)(-1) h(-1) respectively. Dynamic headspace analysis of intact P. obconica plants showed that primin is also directly emitted from undamaged plants, although in smaller concentrations (6.2 ng (g fresh plant material)(-1) h(-1)), whereas miconidin was only emitted in minute amounts (less than 0.4 ng (g fresh plant material)(-1) h(-1)) both from intact plants and from unchopped plant parts. The possibility that primin from P. obconica could be a potential airborne allergen and therefore a source of airborne contact dermatitis is discussed.