Four dolphins that arrived in central China's Hunan airport from Japan on Wednesday successfully passed a radiation test, according to local authorities.

The dolphins traveled via a chartered flight from Taiji Town in southwest Japan and arrived at Changsha Huanghua International Airport at around 5 p.m. after a four-hour flight, said an official surnamed Zeng with the Changsha Entry-Exit Inspection and Quarantine Bureau.

The dolphins are the first batch of live animals that were sent to Hunan from Japan after the earthquake and the Fukushima nuclear leak, said Zeng.

Taiji Town is more than 800 km from the Fukushima nuclear power plant, but the radiation test was still conducted to maintain general safety, said Zeng.

The four dolphins, aged between two and four, were about 2.5 meters in length, said a worker with Changsha Underwater World where the dolphins were sent.

The dolphins will be under quarantine for one month before being displayed to visitors.