Why Japan’s pumping water from Fukushima into the Pacific is a matter of concern?

Japan’s decision to release water from the Fukushima nuclear power plant has been greeted with horror by the local fishing industry as well as China and several Pacific Island states. China – which together with Hong Kong imports more than US$1.1bn (£866m) of seafood from Japan every year – has slapped a ban on all seafood imports from Japan, citing health concerns.
Contaminated water
In 2011, a magnitude 9.0 earthquake off the north-eastern coast of Japan’s main island, Honshu, triggered a tsunami that devastated many coastal areas of the country. Tsunami waves knocked out the Fukushima nuclear power plant’s backup electricity supply and caused meltdowns in three of its reactors. The event is regarded as one of the worst nuclear accidents in history.
Since the accident, water has been used to cool the damaged reactors. But, as the reactor core contains numerous radioactive elements, including ruthenium, uranium, plutonium, strontium, caesium and tritium, the cooling water has become contaminated.
The tainted water is stored in more than 1,000 steel tanks at the power plant. It has been treated to remove most of the radioactive contaminants – but traces of the radioactive isotope tritium remain.
Should we be concerned?
Studies have, in the past, explored the health effects of tritium exposure. However, much of this research has focused on organisms such as zebrafish and marine mussels. Research from France, for example, found that tritium – in the form of titrated water – led to DNA damage, altered muscle tissue and changed movement patterns in zebrafish larvae.
But that’s not everything
In theory, it’s also possible that the potential health issues linked to tritium could worsen due to the presence of other chemical contaminants. In China, researchers discovered that exposing zebrafish larvae to both tritium and genistein – a naturally occurring compound produced by some plants that is commonly found in water – led to reduced survival and hatching rates.