Hawaii faced a new hazard on Sunday as lava flows from Kilauea’s volcanic eruption could produce clouds of acid fumes, steam and glass-like particles as they reach the Pacific, authorities said.

Civil defense notices cautioned motorists, boaters and beachgoers to beware of caustic plumes of “laze” formed from two streams of hot lava pouring into the sea after cutting across Highway 137 on the south coast of Hawaii’s Big Island late on Saturday and early Sunday.

The bulletins also warned that reports of toxic sulfur dioxide gas being vented from various points around the volcano had tripled, urging residents to “take action necessary to limit further exposure.”