The Iran war is unleashing a toxic mix of chemicals, heavy metals and other pollutants that threaten everything from agriculture to drinking water to people’s health. Experts also say it's leaving behind environmental damage and health risks that could persist for decades. They say attacks on oil- and gas-related sites create some of the worst environmental risks because of impacts to air quality and soil and water pollution. But they also worry about potential damage to nuclear sites and critical desalination plants, as well as water pollution that could damage fisheries and important ecosystems.