Vanuatu's Red Cross says ashfall from a volcano on Gaua Island in the north is affecting food and water sources of villagers waiting to be evacuated.
Preparations are being made to evacuate nearly 3,000 people from Gaua should the volcano's activity increase.
There's been an increase in mud flow, ash fall and more explosions from the Gaua volcano in recent weeks.
The water level in the crater lake has also been rising and there are fears that mud could flow from the lake to populated areas.
The local Red Cross disaster management officer, Augustin Garae, says fumes and ash showering the island have been a hazard for people's health.
"The thing that worries us now is the water, it might be contaminated and the ashfall is also affecting all the food crops. That's the sort of thing to be considered and we're looking at the situation."
Augustin Garae says the organisation has been distributing basic items.