POINT COMFORT, TEXASNearly every day for three years, Diane Wilson and a handful of fellow volunteers spent hours poking through the buggy, marshy grasses of the Gulf Coast, combing stretches of pebbly sand, or kayaking beside a huge petrochemical plant, all in search of tiny plastic pellets called nurdles. They found the lentil-sized pieces everywhere, filling gallon bags with them, and submerging bottles to collect water tainted with raw plastic powder.

In March of 2019, Wilson, a retired shrimp boat captain and fisherwoman, loaded a trailer with 2,400 of those samples—46 million individual pellets, she estimates—and drove her pickup truck to federal court to face down Formosa Plastics, the company responsible for the spills. The victory she won there led to what is said