Tar ball is the remnant of oil spills formed in the sea after weathering processes.
The research conducted by NIO scientists on the tar ball samples collected from South Gujarat’s Tithal, Maroli, Umbergaon and Nargol beaches found that its probable source locations are in the vicinity of Bombay High oil fields.
NIO is an institution of Council for Scientific and Industrial research (CSIR), and is a central government entity.
Scientists conducted fingerprint test on the tar ball samples and various oil samples collected from the Bombay High, Cairn and Niko firms to reach a conclusion.
The results were further compared with the published data of Middle East Crude Oil (MECO) and South East Crude Oil (SEACO) and they were not matching, cementing the claim that the oil was from Bombay High and surrounding oil rigs.
The findings have been published in the American Chemical Society s Journal “Environmental Science and Technology”.
The researchers also found that winds, tides and currents play a major role in transporting tar balls to the Gujarat coast.
“But the question is whether it is the operational spill in the Bombay high oil fields or natural seepage from the basin, which is the cause for the formation of the tar ball,” reads the paper, which examined the tar balls that surfaced on these beaches in July 2012.
The scientists of the CSIR-NIO said that detailed research has to be conducted to answer the question whether it is due to natural seepage, transportation of crude oil or operational spills in the water.
Tar balls appearance is a common phenomenon during pre monsoon to monsoon (April to September) along the west coast of India from Gujarat in the North to Karwar in the South.
The NIO has also initiated similar study on the tar balls collected from Goa beaches in 2013, whose initial results, have also pointed out that the Bombay High might be the source of pollution.