From their Science and Technology page:
The tremendous volcanic eruption thought to be responsible for Earth's largest mass extinction — which killed more than 70 percent of plants and dinosaurs walking the planet 250 million years ago — is still taking lives today.
Scientists investigating the high incidence of lung cancer in China's Xuan Wei County in Yunnan Province conclude that the problem lies with the coal residents use to heat their homes. That coal was formed by the same 250-million-year-old giant volcanic eruption — termed a supervolcano — that was responsible for the extinction of the dinosaurs. The high silica content of that coal is interacting with volatile organic matter in the soil to cause the unusually high rates of lung cancer.
Well, no, the Permian–Triassic extinction event predated the rise of Dinosaurs, and might have enabled it. Certainly it did not cause their extinction. And, oh yes, plants can't walk.