ʻE ʻita ʻa e valitaa

ʻE lava ke hoko ʻa e efu valitaa ko ha maumau ʻi he taimi ʻoku fuʻu lelei ai.

ʻI heʻene hoko ko e kau poupou ʻo e valitaa, polycyclic aromatic hydrocarbons, ʻi he taimi ʻoku pulverized feʻunga ai, ʻOku nau fakahehema ke faʻu e efu. Koeʻuhi ko e feituʻu lahi ʻo e valitaa, ʻoku fengaueʻaki lelei mo e ʻea, fakautuutu e fakatuʻutamaki ʻo e efu lolotonga.