Four years ago, I investigated microplastics for the Listener. It was distressing. Since then, countries have been negotiating a global plastics treaty to end plastic pollution, which could be a multilateral pact similar to the Paris Agreement. Their final session is being held this week, from August 5-14 2025, in Geneva, where representatives from 175 countries are gathering.
They’re far outnumbered, though, by plastic industry lobbyists, who some see as a threat to treaty objectives. Also attending are about 50 scientists to provide independent scientific evidence to countries in their deliberations, if asked.
They represent the Scientists’ Coalition for an Effective Plastics Treaty ‒ 450 scientists globally ‒ which is coordinated by Trisia Farrelly, an associate professor of anthropology at Massey University, and a senior researcher for Nelson’s Cawthron Institute.
The coalition is motivated by a torrent of studies showing plastics’ harm. Microplastics and nanoplastics have been found in breast milk, placentas, brains, testicles, artery plaques, tumours and in deep ocean and mountain air. Links between plastics and colorectal cancer are currently being investigated by researchers in Christchurch. Farrelly also points to the Plastics Umbrella Health Review and PlastChem Report summarising hundreds of independently peer-reviewed studies.
One treaty proposal is to phase out “plastic chemicals of concern”. Plastics contain, and can leach, any of 16,000 chemicals, of which at least 4200 are persistent, bioaccumulative, mobile and/or toxic, and mostly unregulated. About two-thirds are untested. Health effects they’re associated with include low birth weight and altered genital appearance in babies, neurodevelopment disorders in children, and fertility problems and cancer in adults.
But the plastics industry says its products are benign. Its representatives have been accused of harassing and undermining the credibility of scientists at the negotiations, which stalled at the last session in 2024.
The industry was valued at US$593 billion in 2021, and its tactics follow the playbook of big tobacco and big oil. Indeed, because plastics are made from petrochemicals, the plastics industry is big oil.
They’ve teamed up with oil and plastic-producing countries to weaken the treaty’s scope. An editorial in Nature explains the stalemate: “So far, the talks have been repeatedly disrupted and delayed by nations with a vested interest in oil and plastics production, including Saudi Arabia, Iran, Russia and China.
“These countries, which call themselves the ‘like-minded group’, are insisting that the treaty should cover only the recycling and consumption of plastics, and oppose curbs on the production of both plastics and specific, named chemicals.”
What’s being negotiated in our name? Five New Zealand officials in Geneva have a negotiating mandate approved in 2024. Parts of the mandate are redacted. It’s weaker than its 2022 equivalent, tending towards waste management and recycling as per the like-minded group.
Yet we officially remain in the “high-ambition coalition” of 121 countries that committed to curbing plastic production to essential items, regulating chemicals for safety, preventing leaks to the environment and providing supportive finance, especially for a just transition.
All negotiating countries have been asked to find middle ground so negotiations can end, says Farrelly. But the scientists’ coalition warns that a high-ambition treaty is crucial to protect people and planet.
It wants better access to negotiations. After the last round, it wrote to the bureau of countries running the talks and the United Nations Environment Programme, saying: “When denied access to negotiations, we are unable to identify the knowledge gaps, misunderstandings or misinformation that require clarification.”
Farrelly is determined and optimistic. “We cannot afford to get this wrong. This is a historic opportunity.”
