"Artificial mussels" offer low-cost solution to nuke wastewater monitoring: Hong Kong's study

HONG KONG, July 10 (Xinhua) -- "Artificial mussels" (AMs) can effectively measure low concentrations of radionuclides in the sea, offering a low-cost solution as global concern over the pollution of radioactive wastes in the ocean rises, according to a cross-institutional study in Hong Kong.

The study, conducted by the Education University of Hong Kong (EdUHK), the City University of Hong Kong, and the University of Hong Kong, highlights a technology that can be applied as a reliable and effective solution for monitoring radioactive contamination around the world.

Akin to natural mussels, the AMs, invented over a decade ago by Professor Rudolf Wu Shiu-sun of the Department of Science and Environmental Studies at EdUHK, have a remarkable ability to soak up a variety of metals, and therefore can be used to measure the concentration of metallic pollutants in the marine environment.

Unlike existing methods, using AMs does not require collecting hundreds of liters of seawater for concentration and analysis, therefore saving the required manpower and cost for sampling and pre-treatment. The cost of each AM is just 1 U.S. dollar, making it viable for long-term and large-scale monitoring of nuclear wastewater.

As of today, AMs have already been in use in 29 countries and regions around the world, the EdUHK said in a press release earlier this month.

"The risks posed by nuclear wastes to marine ecology and human health cannot be underestimated ... The device can play a role in safeguarding environmental and food safety, as it offers authorities around the world a practical and cost-effective way to monitor radionuclides in waters," said Wu.

In addressing the problem of radioactive pollution in the ocean, Wu and his team in 2022 selected three radioactive substances -uranium, strontium, and caesium commonly found in nuclear waste and disposal, as research targets.

The research team then placed the AMs in seawater containing various concentrations of radionuclides, in an attempt to test the devices' absorption and releasing abilities.

Following a series of experiments, results showed that it only takes seven to eight weeks for the AMs to complete the absorption process. After that, they release the radioactive substances on returning to clean seawater, demonstrating that the device can provide a reliable estimate of the concentration and variation of these radionuclides in seawater.