Fishermen of Indonesian and East Timorese may be suffering from skin conditions because of Montara oil spill that ruptured on 21st August, 2009, according to the lawyer representing them.

A full scientific investigation has been demanded by Darwin-based lawyer and spokesman for the Australian Lawyers Alliance, Greg Phelps, on the fifth anniversary of one of Australia's worst oil disasters.

The lawyer noticed swelling and rashes on the skin of villagers after visiting the village Tablolong in West Timor in August 2013 and February this year. The problem started appearing after the oil spill, say villagers.

Phelps said that they saw people who were suffering from skin conditions and they came out of the crowd to show the rashes on their arms and on their neck. Other people have also reported deaths in that village.

Two months were taken to stop the leak and Seaweed farming in Tablolong also appears to have been affected.

"The community reported that their pre-spill production of 500 tonnes has dropped to less than six tonne, which is not much over 1 per cent. And the price has halved because the quality of the seaweed's deteriorated", Phelps said.

The Indonesian government is supporting Phelps to represent fishermen from the Indonesian province of East Nusa Tenggara, including West Timor and of the East Timorese government to represent fishermen from the district of Oecusse, on the north-west coast of the island.

In a statement released to ABC News in July, the company which is responsible for the oil spill, PTTEP Australasia, said that the company was aware of the claims that the oil spill had spoiled West Timorese fishing and seaweed farming population.

According to the statement, any believable evidence has not been received about the oil causing damage to the surroundings in West Timor.

The Montara Environmental Monitoring Program explained that no long-term damage was caused to the marine environment.