A father and son have admitted illegally exporting non-recyclable household waste to Brazil.
Julio Da Costa, 52, and his 28-year-old son Juliano appeared at the Old Bailey.
The pair from Swindon, Wiltshire, exported 750 tonnes of waste to Brazil, in breach of Organisation for Economic Co-operation and Development rules.
The pair will be sentenced along with Edwards Waste Paper, of east London, the firm's director Simon Edwards and sales manager Jonathan Coombe in March.
The father and son ran two companies, which are now in liquidation, and are alleged to have arranged the illegal shipment to Brazil.
They had previously denied the charge at an earlier hearing.
In July 2009, Brazilian authorities accused the UK of dumping unwanted contaminated waste on its shores after 89 containers containing 15,000 tonnes of waste were found on a quay side.
The shipment of "mixed plastics" was sent back to the UK and examined by the Environment Agency (EA).
While it is legal to export plastics for recycling in some countries, it is illegal to export waste.
Andy Higham, head of the EA's national crime team, said: "Illegal waste exports risk harm to human health and the environment in the country of export.
"It also undermines law-abiding recycling businesses back home."
The maximum penalty for illegal waste export is an unlimited fine or up to two years in prison.