Torbay Council said initial samples taken by the Environment Agency after the sewage pumping showed bathing water quality had not been affected.

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Dr Tongesayi told BBC News he was determined to reconcile his initial findings with the outcomes of subsequent analyses of his samples by other means, including the mass spectrometry method.

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So if it gets strong indications that organisms might be present, it will be able to subject samples to a wide range of tests to confirm initial readings.

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