Conservationists have voiced their concern over a recent oil spill off Thailand's east coast that may 'sterilise' corals in the area.

Suchana Chavanich, the vice director of Chulalongkorn University's Aquatic Resources Research Institute, said Thai Oil's pipeline, which ruptured in Chonburi province on September 3, may prove devastating to corals and marine life in the long-term.

The environmental expert said research has shown that oil spills and the chemical dispersants used to break them up can render the corals infertile by inhibiting the production of gametes, or making these cells unsuitable for reproduction.

She said: 'It is essential to closely monitor the spill's mid and long-term effects on marine animals, which will require advanced technology to scan their internal anatomy.'

Suchana added that though the environment can recover, the corals themselves may not be completely restored.

Meanwhile, Voranop Viyakarn, the director of the Aquatic Resources Research Institute, said researchers have begun collecting soil and water samples from the affected area for testing.

He said scientists will conduct metagenomic DNA sequencing to determine the slick's impact on sea animals so far.

He said: 'For now, the research team will continue to study the impacts on marine animals and the environment. We hope to present our findings eventually so we can find long-term solutions to preserve the marine ecosystem.'

Thai Oil, a subsidiary of state-owned fuel giant PTT, said some 70 cubic metres of oil had leaked into the sea off Chonburi when their pipeline burst on September 3.

The accident had left a 5km-long slick which authorities were dousing with 6,000 litres of dispersant.