Levels of radioactive cesium in all fish and seafood sampled in the coastal waters off Fukushima Prefecture last year did not exceed the central government's safety limit for the first time since the 2011 nuclear crisis, a local fishery laboratory has said.

The finding, released Wednesday, that radioactive cesium readings were below the regulatory maximum of 100 becquerels per kilogram was welcomed by the local government and fishermen seeking to allay contamination concerns following the Fukushima No. 1 nuclear plant crisis triggered by the March 2011 earthquake and tsunami.

According to the prefectural fishery laboratory, 95 percent of the 8,502 samples collected in 2016 showed radioactive cesium at levels that were hardly detectable, while readings for another 422 samples were below the limit.

"We were able to present data that fish and seafood in Fukushima are safe," said an official of the laboratory, which is hoping to expand the area and scope of sampling.

The prefectural government has been measuring concentrations of radioactive cesium in fish and seafood since April 2011, with sampling also being undertaken in waters within a 20 kilometer radius of the nuclear plant.

The last time radioactive cesium readings surpassed the government limit was in March 2015.

The proportion of fish samples surpassing the limit has decreased every year since 2011, when the figure stood at 39.8 percent, according to laboratory data.

The figure stood at 16.5 percent in 2012, 3.7 percent in 2013, 0.9 percent in 2014 and 0.05 percent in 2015.