Chemists at Plymouth University have identified the sticky substance that has killed hundreds of sea birds off the Devon and Dorset coast.
Their findings suggest it's a form of Poly Isol Butene, or PIB, used as a lubricating additive in oils to improve performance.
Tamsin Eames reports:
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Bridgwater and West Somerset is considered a Conservative safe seat - in 2010 they had a majority of over 9,000 votes.
Camborne and Redruth is a marginal seat. The Conservatives won it in 2010 by just 66 votes - a 0.16% majority.