Oil additive polymer PIB may be responsible for seabird deaths A sticky substance is washed off a guillemot at RSPCA West Hatch Animal Centre & Wildlife centre near Taunton. Photograph: Ben Birchall/PA A sticky substance that has killed hundreds of seabirds could be a polymer often used to improve the performance of lubricating oil, it has emerged. Professor Steve Rowland, an expert in pollution from Plymouth University, examined the substance found on one of the guillemots washed up on the south coast of the UK. He concluded that it is PIB - polyisobutene - which is used in products ranging from adhesives to sealants and chewing gum. The makeup of the samples he and his team have analysed suggests it was most likely used as an additive in lubricating oil. Rowland, who is funded by the European Research Council to study oil pollution, said: "PIB is used as an additive to lubricants. It looks and feels a little like wallpaper adhesive. When it is caught up in the birds' feathers, it just glues them together. About 300 birds have washed up alive coated in the substance. Scores more have been found dead and naturalists are worried that hundreds could have died and been blown out to sea. The Royal Society for Protection of Birds has also heard reports of birds washing up on the coast of Belgium. Rowland has passed his findings to the Maritime and Coastguard Agency, which is leading the government's response to the incident. Environment Agency scientists have also been working to establish what the substance is. Rowland said he had heard of a similar incident almost 20 years ago when a ship's crew flushed out tanks that had been carrying the substance. He said it could be very difficult to trace the source of this latest incident.