According to the Japan Weather Association's forecasts, the levels of pollen in the air this year will be high in the east and low in the west. A hot summer favors growth of male cedar flowers, the ones that produce the pollen. Furthermore, because winter 1999-2000 was warm, with temperatures 3 to 4 degrees above average, the cedar trees are flowering and scattering their pollen about a week earlier than usual. The Tokyo metropolitan government has measured pollen counts of 3 times the average, and the trees in the capital region scattered their pollen in early February, about 10 days earlier than usual. Meanwhile, in Chiba Prefecture, east of Tokyo, pollen counts are about 10 times the low levels observed last year.
Cypress trees scatter their pollen about a month after the cedar trees do.
Hay fever sufferers need protective devices such as masks and goggles when they go outdoors. These items are selling briskly, particularly among women. But no matter how careful allergy sufferers are, they will inevitably come into contact with some pollen. Allergists point out that these medicines are most effective when people begin taking them two weeks before pollen starts to scatter, so it is best to start taking them early. However, the effects of shots taken this year will not show up until next year or later, so injections are not effective against sudden allergy attacks.