The costs of plastic pollution and the climate fight

While commuting this week, I passed a hole-in-the-wall eatery that sells rice, pasta and quinoa bowls for €7.30, much less than similar items at restaurants near our Paris newsroom. I asked the person behind the counter if the bowls' transparent covers were made of plastic or corn-based material. Plastic, she told me, and in the ensuing conversation, said that the paper takeaway bags she offers customers cost her nine cents more than the plastic ones she used to have. A switch to a non-plastic alternative for the bowl covers would likely be unaffordable. "For the little businesses", she said, it is always a question "of costs".

Plastic and its costs feature in two articles we bring you this week. Mateo Cordier, a researcher in economics and environmental sciences, explains why representatives from 175 countries currently meeting in South Korea to craft a global plastics treaty have reason to be more concerned about the price of inaction than of measures to reduce plastic production and pollution. Amélie Châtel, a professor of aquatic ecotoxicology, looks at how micro- and nano-plastic waste in the oceans accumulate in marine life, causing toxic effects, with potential health risks for humans who consume seafood.

The costs of tackling the effects of climate change were at issue during the UN COP29 conference in Azerbaijan that ended Sunday. Richer countries pledged $300 billion a year by 2035 to help poorer countries, but some delegates said it wasn't enough. Nuno Fernandes, a professor of financial management, identifies four ways to help entice private capital to make green investments. Jordi Roca Jusmet, a specialist in ecological economics, notes that COP agreements have focused on reducing demand for fossil fuels rather than limiting extraction, even though limits are "the only certain way to rein in" greenhouse gas emissions.

The International Day to Eliminate Violence Against Women, which took place Monday, targets another global crisis. In France, the open trial over the mass rape of Gisèle Pelicot, who was assaulted by her ex-husband and dozens of other men in her home for nearly a decade, has expanded the conversation about sexual violence. Tadgh Tobin, a PhD candidate in forensic psychology, explains why the trial may help other non-stereotypical survivors of assault come forward. In Italy, women mayors are three times more likely to be targeted with political violence than their male counterparts, according to a recent study. Gianmarco Daniele, a co-author, writes that sexist double standards, not local policy choices, are behind the higher rate of attacks.

This week, we also offer insight into a development in the story of quantum mechanics. On the 100th anniversary of a key doctoral thesis, Laurie Letertre, a researcher in the philosophy of physics, looks at why its author, Nobel laureate Louis de Broglie, walked away from his famous "pilot wave" theory – questions relating to which are still being debated today.