'I see cocaine in wild shrimp in Suffolk': meet the scientist who analyses our wastewater; Water detective Dr Leon Barron studies London's wastewater, analysing it in all its chemical, narcotic, polluted glory, before and after treatment. Amazingly, he still drinks the stuff from the tap

Byline: Emma Beddington If you live in London, Dr Leon Barron knows what you're up to. He knows what prescribed drugs you're on -- painkillers, antidepressants, antipsychotics or beta blockers [...]