RADIATION from Japan’s (日本) 2011 Fukushima (福島) nuclear disaster has for the first time been detected along a North American (北美洲的 ) shoreline, though at levels too low to pose a significant threat to human or marine life, scientists said.

Trace amounts of Caesium-134 and Caesium-137 were detected in samples collected on 19 February off the coast of Ucluelet (尤克盧利特 ), a small town on Vancouver Island (溫哥華島 ) in Canada’s (加拿大) British Columbia (卑詩省), said Woods Hole Oceanographic Institution (伍茲霍爾海洋研究所) scientist Ken Buesseler.

“Radioactivity can be dangerous, and we should be carefully monitoring the oceans after what is certainly the largest accidental release of radioactive contaminants to the oceans in history,” Buesseler said in a statement.

The levels the group detected are extremely low. For example, swimming in the Vancouver Island water every day for a year would provide a dose of radiation less than a thousand times smaller than a single dental X-ray, Woods Hole said last Monday.

Buesseler said he expects similar low caesium levels to gradually reach other North American shores, possibly extending along the US (美國) West Coast from Washington state (華盛頓州) to California (加州).

The Woods Hole Oceanographic Institution said its conclusions were drawn from research it collected from community groups and a network of local academics and aquariums that collect water samples and fund radiation testing.

(Reuters, 6 April 2015)