Sri Lanka shipped out to Britain on Monday the final batch of containers that include thousands of tonnes of illegally imported waste, according to officials. Many Asian countries have in the past years been refusing to accept an onslaught of refuse from wealthier nations and have started turning back the unwanted shipments.

Britain's waste arrived in Sri Lanka between 2017 and 2019 and the shipment was labeled as "used mattresses, carpets, and rugs". However, it turned out that it also contained biowaste from hospitals including body parts from mortuaries, customs officials said.

Some containers were not chilled, which resulted in a repulsive smell. The 45 containers loaded onto a ship at a Colombo port on Monday were the last batch of 263 containers carrying around 3,000 tonnes of waste.

Vijitha Ravipriya, the customs chief noted that "There could be fresh attempts to import such hazardous cargo, but we will be vigilant and ensure that this does not happen again."

The first 21 containers that carried medical waste were sent back to Britain in September 2020. A local company had imported the waste from Britain, saying it was planning to recover the springs from used mattresses and cotton to be reshipped to producers abroad. But customs did not find any credible evidence of such "resource recovery".

A local environmental activist group filed a petition in which it requested that the waste be sent back to its sender, and Sri Lanka's Court of Appeal upheld the petition in 2020. Customs maintained bringing the containers to the country is a violation of international law governing the shipment of hazardous waste, including plastics.

A Sri Lankan investigation in 2019 concluded that the importer had reshipped over 180 tonnes of waste brought into the island to India and Dubai in 2017 and 2018. The Philippines, Indonesia, and Malaysia have also returned hundreds of containers of refuse back to their countries of origin.