In the shadow of President Donald Trump’s tariff fights, a different kind of trade war is playing out involving candy wrappers and plastic bottles.

On July 1, Malaysia, which received more discarded plastic from rich nations than any other developing country last year, effectively banned all shipments of plastic waste from the United States.

That might not seem like a big deal. But the United States has increasingly relied on countries like Malaysia to deal with plastic trash. American scrap brokers sent more than 35,000 tons of plastic waste to Malaysia last year, according to trade data analyzed by the nonprofit Basel Action Network, which tracks plastic waste issues.

Last year, after seizing more than 100 shipping containers of hazardous materials sent from Los Angeles that had been improperly labeled as raw materials, the Malaysian environment minister, Nik Nazmi, told reporters, “We do not want Malaysia to be the world’s rubbish bin.” The country’s Ministry of Investment, Trade and Industry did not respond to a request for comment last week.

Turmoil in the little-known trade in plastic waste has its roots in a decision by China in 2018, for the same reasons as Malaysia, to ban imports of wastepaper and plastic. Before that, China had for years accepted as much as half of the globe’s discarded plastic and paper.

Western nations have since struggled with a buildup of plastic trash. The United States recycles less than 10% of the plastic it discards. (Food and other contamination in plastic waste hinders recycling, and a significant portion of plastic, like chip bags that contain layers of different plastics and other materials, simply can’t be recycled economically.)

The rest ends up in landfills, is burned or is shipped overseas. And while new overseas destinations have emerged, a growing number of countries are starting to say no to trash. This year, Thailand and Indonesia also announced bans on plastic waste imports.

The world produces nearly 500 million tons of plastic each year, more than double the amount from two decades ago, and a growing amount of plastic waste is turning up on coastlines and riverbanks, as well as in whales, birds and other animals that ingest them. Researchers have estimated that one garbage truck’s worth of plastic enters the ocean every minute.

China’s ban “sent shock waves through the global plastic-waste trade,” said Tony Walker, a professor at the School for Resource and Environmental Studies at Dalhousie University in Halifax, Nova Scotia, who researches the global flow of plastic waste. The countries that started to accept discarded plastic “quickly became overwhelmed,” he said. Much of the plastic trash ends up dumped in landfills or is burned, which releases harmful air pollution, or is simply released into the environment.

People in rich countries may assume that the plastic they diligently separate is being recycled, he said, something he termed “wish cycling.”

That’s why experts increasingly say that, on top of investing in recycling infrastructure, policies are needed to help rein in plastic production, such as by curbing demand for single-use plastics. Some countries have also called for caps on plastic production.