New Delhi: Japan's decision to release radioactive contaminated water from its wrecked nuclear plant in Fukushima into the sea by 2022 has led to alarm bells ringing in India with experts warning it would set a wrong precedent and impact aquatic and human life along with coastal belts of several parts of the world.

The contaminants of the massive quantities of nuclear water will include radioactive isotopes such as cesium, tritium, cobalt and carbon-12 and may take from 12 to 30 years to decay. It will destroy everything it comes in contact with almost immediately and cripple the economy related to the fishing industry and lead to a spectrum of diseases, including cancer.

This will be the first incident of high volumes of radioactive water being released in the sea and can set a wrong precedent for others to follow. Concerns related to the environment and health are crucial for the existence of the human race. Therefore, alternative arrangements may be debated globally, A K Singh, director-general of health science at the Defence Research Development Organisation (DRDO), told PTI.

On March 11, 2011, a 9.0 magnitude earthquake struck off the north-eastern coast of Japan, triggering a 15-metre tsunami that damaged the 5,306 MW Fukushima nuclear plant. It is the second biggest nuclear disaster in the history of nuclear power generation after Chernobyl in 1986.

After the accident, 1.2 million tonnes of radioactive contaminated water released from the reactors in over 1,000 tanks were kept in a cordoned off large area near the Fukushima plant.

However, authorities are running out of space as the plant is to be decommissioned and the Japanese government has decided to release the radioactive contaminated water in the sea starting 2022.

The decision to release the radioactive water was taken on October 16, 2020 after years of debate.

Singh, among the Indian government's top nuclear health scientists, said the release of contaminated water into the ocean will directly impact human and aquatic life.

The possibility of ingestion of tritium in humans will increase and since this isotope will distribute in all organs in humans. Radioactivity monitoring in fish and other aquatic life in the near vicinity (coastal areas) and drinking water will be necessary. Deposition of the radioactive elements on the rocks has also to be seen, he said.

While Japanese authorities have said the water would be diluted before being released and it would only contain only tritium, other health experts who have been monitoring the issue said the risk involved should never be undermined. 

Yudhyavir Singh, assistant professor of anaesthesia and critical care at the All India Institute of Medical Sciences, said the risks will depend entirely on the amount of the contaminants present in the nuclear wastewater and their nature.

Mostly contaminants are radioactive isotopes which include cesium, cobalt, carbon-14 and tritium. The half-life of cesium is 30 years it will take 30 years of half of the material to decay. Also the half-life of tritium is 12 years, he told PTI.

All the radioactive isotopes are carcinogenic and can induce cancer on prolonged exposure. In Chernobyl, it has been seen in the rise of thyroid cancer post-nuclear leakage after 20 years, he said.

Once the water is released into the ocean, it would be advisable to move and stay away from the coastal area in the region while completely avoiding seafood, added Yudhavir Singh, who has several publications on critical care and is a renowned researcher too.

In the past, it has been seen that radioactive material discarded in France travelled to the North Atlantic and Arctic Oceans and found in the bodies of seals and Tortoises, he said, warning that South-East Asian nations will be at higher risk. 

Environmentalists and several organisations, including Safecastand Greenpeace, have urged the Tokyo Electric Power Company (TEPCO), the operator of the Fukushima plant, to build more storage tanks and keep the water stored.

Greenpeace claimed the water could change human DNA if consumed.

Tritium is a beta emitter with low energy so causes damage to the DNA leading to genetic damage and affecting reproductions. It will depend upon the radioisotopes contaminants in the water. Cesium has a half-life of 30 years and will be the last to decompose, Yudhyavir Singh said.

The quantity of cesium in the nuclear wastewater may take 180-300 years to decompose, he said.

Citing studies from the World Health Organisation, M C Misra, former director of AIIMS, Delhi, said an increase for specific cancers for certain subsets of the population inside the Fukushima Prefecture is very likely.

A 2013 report predicts that for populations living in the most affected areas there is a 70 per cent higher risk of developing thyroid cancer for girls exposed as infants, a 7 per cent higher of leukaemia in males exposed as infants, a 6 per cent higher risk of breast cancer in women and 4 per cent higher risk, overall, of developing solid cancers for females, Misra told PTI.

Misra, who has dealt with all types of medical cases, including that of radiation, said Japan could have easily prevented the entire accident.

The Japanese focused on the prevention principle without paying due attention to the mitigation principle as if it was sure that an accident was impossible. The power unit of the Fukushima plant was built on the basis of a design developed in 1960 and, therefore, the station was not ready for a crisis situation of the 21st century, Misra said, citing the complexity of such situations.