Do Marine Microplastics pose a Biosecurity risk for the Aquaculture Industry?
There are an estimated 50 trillion plastic particles floating on the surface of the world’s oceans, largely originating from textiles and when larger pieces of plastic break down. These microplastics have been found in zooplankton, and species used for human consumption including bivalves, crustaceans, fish and other marine vertebrates.
A growing body of evidence suggests that microplastics are impacting marine creatures, affecting growth rates, increasing stress, and potentially contributing to higher mortality rates. A recent study published in Trends in Microbiology now summarises the evidence that microplastics can act as a vector for transmission of bacteria into filter feeding bivalves. These bacteria (particularly some Vibrio strains) can cause disease outbreaks in cultured bivalve species.
A recent blog by the Global Aquaculture Alliance on the issue suggests that although research on the impacts of microplastics on the aquaculture industry is in its infancy, the risks are not new. The pathogens that could be transmitted on microplastics are already found naturally in oysters and mussels, and producers monitor for them in aquaculture operations.
Despite limited research the risks to human health from ingesting microplastics are thought to remain relatively low. However, the potential economic impacts resulting from increased incidence of disease outbreaks in bivalve farms remains an issue, and further research will be required to better assess the risks.
RS Standards CLAMS initiative is a useful mechanism to ensure potential biosecurity risks are monitored on a regular basis by aquaculture producers that share a joint water body, such as a bay. RS Standards are also a strategic partner to the Responsible Plastic Management (RPM) Program, for further details please visit our Plastic Management page.