Scratch tests (SCT) with powdered commercial spices were performed in 70 patients with positive skin tests to birch and/or mugwort pollens and celery. Positive SCT to aniseed, fennel, coriander and cumin--all from the same botanical family (Apiaceae) as celery--were observed in more than 24 patients. Spices from unrelated families (red pepper, white pepper, ginger, nutmeg, cinnamon) elicited positive immediate skin test reactions only in three of 11 patients. Specific serum IgE to spices (determined in 41 patients with positive RAST to celery) up to class 3 were seen especially in patients with celery-mugwort or celery-birch-mugwort association, and concerned various botanical families. Celery-birch association pattern was linked to positive reactions (RAST classes 1-2) to spices from the Apiaceae family only.