Japan's Fukushima Nuclear Wastewater Discharge: Is Seafood Still Safe to Eat?

On August 24, at around 10:00 a.m. local time, Tokyo Electric Power Company (TEPCO) held an extraordinary press conference and announced that it would begin discharging nuclear-contaminated water from the Fukushima Daiichi Nuclear Power Plant into the ocean at 1:00 p.m. local time that day. The first discharge will last17 days, with approximately460 tonsreleased per day, totaling about7,800 cubic meters of nuclear-contaminated water. TEPCO stated that it had sampled and tested the nuclear-contaminated water to be discharged into the ocean, and the results showed that the concentration of tritiumhad "met the standard".

The Fukushima nuclear wastewater contains 64 radioactive elements, includingtritium and carbon-14, which cannot be completely treated and will enter the ocean along with the nuclear wastewater.

Although tritium has relatively low radioactivity and cannot penetrate the human body without direct contact, it can enter the human body through daily drinking water, or gradually accumulate in the body through the food chain. For example, in an environment containing tritium, tritium is absorbed by plants and then transferred to animals through the food chain, indirectly ingested by humans and ultimately entering the human body. This pathway increases the likelihood of human exposure to tritium and may well cause chromosomal aberrations. Meanwhile, carbon-14 accumulates in marine organisms, i.e., fish, and the abundance or concentration of accumulated carbon-14 may be 50 times that of tritium.

Once humans consume seafood contaminated with radioactive elements, it may cause internal exposure (internal contamination), inducing radiation sickness and increasing the risk of diseases such as cancer. Even low-dose radiation exposure may cause unpredictable harm, such as genetic damage.

The Chinese government has long established strict limits on the concentration of tritium in various foods, especially in infant food, where the tritium content must not exceed 300 becquerels per kilogram (Bq/kg), while the tritium content of other foods must not exceed 3,000 becquerels per kilogram (Bq/kg).

The Japanese government has not yet announced the tritium concentration in the nuclear wastewater, but this concentration is certainly higher than that of water in general use. Although the Japanese government has repeatedly promised to dilute the tritium concentration in the nuclear wastewater to below one-fortieth of the national tritium concentration standard before discharge, the nuclear wastewater problem remains severe, because each tank of nuclear wastewater contains far more harmful substances than tritium alone.

Since the Fukushima nuclear accident in 2011, China has established strict testing standards for food imported from Japan. Imported food from designated regions requires a certificate of compliance for radioactive substances issued by the Japanese government and must be tested by Chinese inspection agencies before entering the market. Radioactive substance monitoring has been incorporated into national food safety monitoring. Therefore, seafood purchased through proper channels basically meets the standards and can be safely consumed. When purchasing seafood, attention should be paid to origin and label information.

Furthermore, when testing whether food is contaminated with radioactive substances from nuclear waste, monitoring authorities should use accurate and reliable reference standards and professional analytical testing instruments to determine the concentration of contaminants in food, thereby conducting effective risk monitoring.