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Japan Sowed Seeds of Its Pollen Problem

Health: More people are susceptible as cedar, cypress species planted 30 years ago begin releasing allergens.


TOKYO — What on earth is ailing the weeping, sniffling, miserable Japanese seen on every street corner these days?

Not the nation's worsening recession, its political dithering, the Asian economic crisis or even the Hong Kong avian flu. No, chances are the culprit is Cryptomeria japonica, a.k.a. the Japanese cedar tree, once one of the nation's most beloved species and now the reviled producer of the pollen that has unleashed a dreadful allergy on one in five urbanites here.

Japan's ill-fated love affair with the cedar is a classic tale of the unintended consequences of a seemingly benign environmental policy.

For centuries, shoguns and peasants have had a special affection for the cedar, known here as sugi. Besides its tall, noble good looks, the sugi is also extremely fast-growing, hardy and perfect for home-building.

After World War II, in an attempt to replenish forests that had been felled for firewood or scorched by bombs, the government offered generous subsidies for tree planting. Between 1955 and 1972, in national forests and on private land alike, Japanese eager for greenery and timber opted, en masse, to plant about 600 million acres of sugi and its almost equally allergenic cousin, the hinoki Japanese cypress. Now experts say at least 10% of Japan's landmass is covered with the two species.

Although sugi trees have been growing in Japan for thousands of years, the related allergy was not identified until 1964, according to Dr. Sakae Inouye, one of Japan's leading experts on the cedar problem. Because it takes 30 years for a sugi tree to mature and begin throwing off its pollen, it was not until the 1980s that Japan began to realize the magnitude of this arboreal gaffe.

Since then, things have only gotten worse. A recent survey by the Tokyo metropolitan government found that 19.4% of residents suffer some degree of cedar allergy, up from just 7% in 1983.


This spring, Koji Murayama, the chief pollen forecaster at the Japan Weather Assn., announced that global warming will almost certainly increase the pollen count because warmer weather in July prompts sugi to release more pollen the following spring.

Murayama based his calculations on two assumptions. First, he estimated that the average temperature will increase by 1 to 2 degrees centigrade by 2050. Second, he calculated that 40% more cedar trees will reach maturity over the next 50 years because sugi trees are still being planted, albeit in smaller numbers.

Based on those assumptions, Murayama forecasts an 80% increase in the number of allergy patients by 2050. If he is correct, that would mean one in every three Japanese citizens would be affected for up to four months of the year.

Already, the afflicted, who sometimes develop insomnia and rashes as well as the usual hay- fever symptoms, spend at least $40 million a year on remedies and medical treatment, according to the Japan Allergy Assn.

Murayama, himself an allergy sufferer, said it is possible to fight sugi allergies. He suggests taking note of pollen forecasts to prevent unnecessary exposure; using air cleaners indoors; and wearing an allergy mask, smooth clothing that pollen won't stick to and a wide-brimmed hat to keep one's hair from being contaminated while outdoors.

"Problem is, when you wear the goggles and the mask and a vinyl raincoat, you look like a bank robber, so I really can't recommend this to people," he said. Tokyo has a hotline that provides up-to-date information about which way the dreaded pollen--which can travel up to 60 miles--is blowing.

Cedar-bashers, calling themselves the Assn. of People Who Detest Cedar, have started their own Internet home page; they advocate cutting down some of the forests. And sufferers have their own parliamentary lobby, the Assn. of Sneezing Lawmakers, a group of 60 allergic politicians from the ruling Liberal Democratic Party, or LDP, that is pushing for more research into cedar pollenosis.

Alas, the sugi trees are likely to outlast even the perennial LDP. Cedars planted by the Tokugawa shoguns nearly 400 years ago at their burial place in Nikko are still going strong, and sugi trees in a forest on the island of Yakushima in Kagoshima prefecture are believed to be 2,500 years old.

Prospects for cutting down the newcomers are dim. Although the first postwar crop should be ready for harvest in about a decade, importing timber is so much cheaper than logging in Japan, primarily due to labor costs, that anyone who tried to fell and sell the sugi forests would probably go broke.

The Nature Conservation Society of Japan advocates gradually harvesting the cedars and replacing them with a diverse selection of native broadleaf trees--particularly in national forests, which the group believes should never have been logged and planted with sugi in the first place. But even environmentalists recognize that the current economics of timber mean that little can be done any time soon.

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