ST. PETERSBURG, April 22. /TASS/. Scientists from St. Petersburg and Vladivostok have discovered a threat of radioactive contamination to the Kuril water area stemming from the discharge of water from Japan’s Fukushima-1 nuclear power plant, the press service of St. Petersburg State University (SPBU) told TASS.

"Oceanologists from St. Petersburg State University and the V. I. Ilyichev Pacific Oceanological Institute of the Russian Academy of Sciences have modeled the paths of the spread and degree of contamination of the South Kuril Fishing Zone (SKFZ) by waters discharged from the Fukushima-1 nuclear power plant. Scientists hypothesize that coastal areas of the Kuril Islands could become contaminated," the message reads.

The report details the accident that occurred at the Fukushima-1 nuclear power plant in 2011 due to an earthquake and tsunami, which led to the release of radioactive contamination. In order to contain its spread into the environment, technical radioactive water began to be stored in large tanks near the nuclear power plant, with more than 1.25 million tons accumulating there by 2023.

The Japanese government and the International Atomic Energy Agency (IAEA) assure that this process does not threaten the environment or human health. However, less than a month after the start of the discharge, the media reported that traces of the radioactive isotope tritium had been found in the waters of the Pacific Ocean at the northeastern border of the port. According to the reports, the concentration of the isotope in the water was 10 becquerels per liter, which is 10 times higher than the normal values.

Scientists' research

Scientists from St. Petersburg State University together with their partners from the V.I. Ilyichev Pacific Oceanological Institute of the Russian Academy of Sciences have studied the water area of the South Kuril Fishing Zone, a highly promising fishing area in Russia. They also analyzed the potential path of the contaminated water and mechanisms for removing these pollutants.

"Many experts claim that most of the polluted water is picked up by the Kuroshio flow and carried eastward from the coast of Japan into the Pacific Ocean, but polluted markers can still be found near the Kuril coast. According to our observations, the 'dirty' markers reach the borders of the SKFZ and are carried far to the north. They enter the Sea of Okhotsk through the Kuril straits," the press service quoted Maria Lebedeva, an oceanology student at St. Petersburg State University who took part in the study, as saying.

According to the press service, the researchers used satellite monitoring data from 1993, as well as the marker tracking method, which allows calculating a large number of trajectories of passive tracers that simulate pollution. As a result, the study showed that the first toxic particles entered the Kuril water area 13 days after the discharge of water from the nuclear power plant. Their maximum number was recorded on the 25th day, after which their concentration began to decrease, but even on the 90th day these markers still persist. The highest number of polluting particles was recorded from the end of August to the end of October, which could be the most potentially hazardous time for fishing in the South Kuril Fishing Zone.

In the future, the scientists plan to apply for a grant from the Russian Science Foundation to conduct a joint study with Chinese scientists.