Some of the birds rescued after being covered in an oil additive have been released back into the wild.

BBC: First birds released after south coast oil rescue

Birds washed ashore on the south coast after being contaminated with an oil additive have been transferred to a wildlife centre in East Sussex.

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The RSPB has called for ships at sea to be banned from discharging an oil additive which contaminated hundreds of birds on the south coast of England.

BBC: RSPB calls for ban on seabird pollutant

An RSPCA spokeswoman said there was no connection between the incident and the birds that washed up on the south coast of England covered in an oil additive, as the types of oil were different.

BBC: RSPCA collects oil spill birds off Kent coast

For owners who accept the offer, the replacement oil contains an additive from BG Products Inc.

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Its bitter leaves are an ingredient in South Indian rasam and curries, and its oil is a common additive to cosmetics, laundry soap, shampoos and toothpaste.

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In Russia's Black Sea oil port of Novorossisk, for example, a local British businessman, Clive Rumens, wanted to set up a small factory producing a simple additive that makes crude oil pour more easily.

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Last year, Pemex had to abandon its second tender for ethanol to be used as a gasoline additive because the offers made were above the price the oil company was prepared to pay.

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Oil companies started using MTBE in the 1980s to replace lead as an antiknock additive in gasoline.

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At the same time, the high price of oil is fuelling demand for ethanol, which is used as both a substitute for and an additive to petrol.

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