RÉSUMÉ
BACKGROUND AND OBJECTIVES: Abundance of Japanese cedars (JC) in Cheju Island has caused some of the island's residents to suffer from severe allergic symptom in the spring time. This study was carried out to verify the presence of JC allergic rhinitis (AR) in the island. Materials and Method: We performed a history survey, skin testing and nasal provocation test to JC and other common allergens for 170 residents who have symptom of AR. We also performed the same tests in 18 Japanese who had history of AR to JC and have lived in Korea more than 3 years. And as a control, skin tests were performed for 581 patients who live in Seoul. RESULTS: Positive reactions to JC were seen in 22.4% of the resident group. The prevalence rate was remarkable in the state capital of Cheju. These reactions were associated with conjunctivitis, dermatitis, asthma and food allergy. All the 18 Japanese patients were sensitive to JC. However, the allergic symptoms disappeared within 1 year after the move to Korea. And there were no patients sensitive to JC in the control subjects. Conclusions: We confirmed the presence of AR of JC in Cheju island. The distribution is comparatively coincided with JC and/or air pollution and this result indicate that environmental factors can be involved in the manifestation of the disease.