Plant-based compostable plastics are going to landfill rather than recycling because almost all Welsh councils are unable to deal with them.
The growth of the anti-single use plastics movement has seen a rise in the number of businesses selling food and drink in compostable containers.
But of the 13 councils that responded to BBC Wales, only Caerphilly collects and composts such products.
The Welsh Government has rejected calls to invest in composting infrastructure.
The technology for plant-based compostables has come so far that it is hard to tell which is plastic and which is the greener alternative.
Many businesses selling food and drink are now turning to the containers in a bid to be greener.
But Keep Wales Tidy said there was a risk that they could lead to “unintended consequences” because of the lack of places that can compost them.
How it works
Food waste is recycled using a process called anaerobic digestion, helping to produce electricity and fertiliser as by-products.
But plant-based items, including those made from polylactic acid (PLA) by companies such as Vegware, must be composted in an industrial composting process which requires heat and oxygen, otherwise they do not degrade.
Photo: Brian Yurasits
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