A 10-day summer student exchange trip between Rapid City and Nikko City, Japan, has been canceled because of parental concerns over safety issues about a damaged nuclear plant that continues to leak radiation.

"We decided to cancel the 10-day summer exchange to Japan because of too few students," said Travis Sutterfield, president of the Rapid City Nikko City Sister City Association. "And Nikko has other things to worry about than our children right now."

The two areas have enjoyed annual cultural exchange trips since the sister city program was established with Japan in the early 1990s. A delegation of students from Nikko City is still scheduled to visit Rapid City this summer.

Rapid City parents started pulling their children out of the 2011 exchange trip when the nuclear power plant catastrophe became an ongoing safety concern after the March 11 earthquake and tsunami in Japan. The level of radiation that continues to leak from the crippled Fukushima Dai-ichi nuclear plant was upgraded this week to a level 7 from level 5 on the International Nuclear and Radiological Event Scale.

Despite a declaration of safety for tourists by Nikko City, Sutterfield said he can't blame parents for pulling out of the trip. The official website of the city government in Nikko City says testing for radiation levels in its water sources, air and food supplies have all been proven to be within safe limits. That information is available online at www.city.nikko.lg.jp/gyousei/documents/sengen-e.pdf

In response to the canceled trip, the sister city association has decided to replace its annual East Meets West fundraiser -- which helped pay for travel costs -- with a tsunami/earthquake relief event, Sutterfield said. A silent auction is scheduled for 2 p.m. to 4 p.m. Saturday at the Peace Officers Club, just off Catron Boulevard, at 2500 Golden Eagle Drive. Food will be served.