Japanese tourists returning from trips to Europe between May 1 and May 5 will have the opportunity to test the food and souvenirs they are carrying for possible dangerous levels of radioactivity.

Officials of Japan's Ministry of Health and Welfare informed the press last week that they plan to set up radioactivity check points at two places in Tokyo International Airport for the use of returning travelers.They explained that since the Chernobyl nuclear power plant disaster in the Soviet Union near Kiev two years ago, a growing number of Japanese tourists returning from visits to Europe have asked to have their purchases inspected for excess radioactivity.

Ministry authorities pointed out that these requests probably stemmed from news reports that their experts have been regularly measuring the radioactivity of all imported foods since the Chernobyl plant blew its top on April 26, 1986.

Japanese importers of food items from the European region have been directed by the ministry in the intervening years to send back to the countries of origin all those products containing cesium of more than the level of 370 becquerels per kilogram.

Japan's health experts advised that the Chernobyl accident spewed forth highly radioactive clouds that were picked up at that time by winds that scattered the unhealthy elements around much of the world.

But the fission products, including radioisotopes of plutonium, iodine and cesium and other radioiso topes that cannot be found in nature, contaminated some of the soil, water and vegetation throughout Europe.

Although the ministry officials don't know just how many of the estimated 270,000 Japanese going abroad this week will be traveling to Europe, they anticipate that the figure will be significantly higher than in past years during Japan's Golden Week - a string of holidays extending from April 28 through May 5.

One ministry official noted that the steady and sharp appreciation of the yen vis-a-vis the U.S. dollar and most European currencies since February 1985 is encouraging Japanese tourists to travel farther each year.

When they come back to Japan, commented one ministry official, we expect many of them to be carrying considerable quantities of European fruit, nuts and vegetables along with other souvenirs. However, he conceded that his ministry has no idea how many will want to have their purchases tested for excessive levels of radioactivity.

Don't use my name, but I'd like to ask my superiors what our testing people should advise tourists to do with their purchases if the results show overly high levels. What if they just leave them at the testing centers and walk away?