Police said the accident happened at 7.30am on the Dan Sai-Nakhon Thai road.
Police said Banthit Meenarak, the driver of a pickup with five passengers, lost control because the road was made slippery by a latex spill. a 60-year-old monk, Phra Boonlert Saiyud, was among the injured.
Banthit's pickup then collided with another pickup driven by Jirapa Pinyawong, 55, who was not injured.