Several states—including the biggest, California—have moved to partially or fully ban the use of nonstick chemicals known as PFAS in firefighting foam. But many of these bans won't take effect for years or, in some cases, many years.

On this episode of Parts Per Billion, we talk with Bloomberg Law California correspondent Emily C. Dooley about the Golden State's own recently enacted PFAS ban and its long, winding journey through the state's legislature.