World Aquaculture December 2020

26 DECEMBER 2020 • WORLD AQUACULTURE • WWW.WA S.ORG plastic waste. Marine sources of plastics are believed to be dominated by the loss of fishing gear. However, without accurate data, it is complicated to manage the issue and develop policies to ensure improvements. The majority of the data extrapolated today comes from beach clean-up operations, coastal surveys and separation of waste to determine their origins. There are limitations, however, especially as these activities do not take place everywhere and are not necessarily conducted with the same methods or to the same scale. Being the fastest-growing food-production sector, aquaculture farms need to manage the quality and food safety of their products while minimizing the environmental impacts of production. As in all other food production sectors, the use of plastics by aquaculture, e.g. for equipment and packaging, is inevitably going to grow concurrently with the sector. In 2018, the Aquaculture Stewardship Council (ASC) recognized the importance of understanding the extent of plastic usage in aquaculture and the procedures for its management and disposal. Inventory of Plastic Usage is Essential for Management Plastics are used at every level of aquaculture production, whether it is for tanks, nets, feed bags, liners, piping, polystyrene boxes, product transportation or chemical storage. In addition, there are the general plastic products used daily by employees in many industries, such as plastic cups and drinking water bottles. Many of these products are considered essential for normal operations but, in many cases, farmers reviewing an inventory of products and materials are surprised by the volume of plastic waste they produce. Categorizing the volume, location and use of plastics on a farm is an essential tool to offer a broader perspective on products and life cycle management to farmers and investors; this is referred to as an inventory of plastic usage. In general, the drive to evaluate the use of plastics is triggered by the request for ‘keeping a clean house’ coming from seafood buyers and societal perceptions (i.e. social insurance and social license to operate) and therefore this varies from one country to the next, depending on cultural perceptions of aquaculture operations and the stringency of regulations. Managing plastics in operations comes with planning and development of procedures, their implementation and responses to events where loss of gear and waste management failures occur. During inventory exercises, the initial perceptions and assumptions regarding plastic use and waste are underestimated more often than not. The inventory can be used to map where alternatives to plastics can be used (e.g. wood, concrete, etc.), ultimately ensuring a decrease in the overall dependency on plastic material. It can also identify the specific needs of a given farm or company, for example, where open vs closed systems have different considerations for plastic wastes and risks for introduction into the environment. Producing plastic inventories can provide a great mechanism to raise awareness and form the basis for developing a dedicated general waste management plan (howmuch plastic, in which operation and how to dispose). These plans can then incorporate specific measures including, for example, an evaluation of the risk created by the degradation of the plastic product itself over time (see below). In some cases, the shelf-life of plastic structures can be regulated by government or associations, with recommendations given by equipment manufacturers. TOP: Material collected in a manta net from the Mediterranean Sea (2019). MIDDLE and BOTTOM: Material collect in the manta net is captured on a stainless-steel filter (10-µmmesh size), where larger plastic particles can be seen alongside small biota (Photos: Julia Farkas, SINTEF Ocean).