[Characteristics of pollen scattering from male sugi flowers in relation to occurring of symptoms in Japanese cedar pollenosis patients].

Generally, airborne scattering of sugi (Cryptomeria japonica D. Don) pollen begins to be observed coincidentally with the flowering of the male sugi flowers between February and April. However the male sugi flowers disperse a certain amount of pollen in early January, only small levels of which can be detected with a Durham's sampler. In some Japanese cedar pollinosis patients, allergic symptoms have been reported to occur in early January. Among 1,366 Japanese cedar pollinosis patients studied, 265 have experienced allergic symptoms before the first day of pollen scattering as determined with a Durham's sampler. Accordingly, it is suggested that substantial amounts of sugi pollen are scattered from early January, and that clinical symptoms can be induced in highly sensitive Japanese cedar pollinosis patients from early January, even before the flowering of sugi.