A team of scientists, led by Dr Ettore Zuccato from the Mario Negri Institute for Pharmacological Research in Milan, were stunned by their findings when they took reading for the concentration of a cocaine by-product in the River Po.

The river was found to be carrying the equivalent of some 4kg of cocaine every day, rubbishing official figures that stated that less than 0.1% of young adults had taken the drug ‘within the last month’.

According to Dr Zuccato’s findings almost 3% of the city’s young adults would have had to consume a 100mg dose every day to produce the quantity of the by-product found.

The chemical tested for was benzolecgonine (BE), which is found in the urine of cocaine users and made its way into the Po via the sewer system.

It is a by-product of the body’s metabolism of cocaine and cannot be produced any other way.

The study, published in the journal Environmental Health, suggests the people of fashion-capital Milan are taking cocaine with a street value of £84 million every year.

Dr Zuccato described the results as staggering, saying his team expected to find quantities more in line with official figures.

The researchers now plan to carry out similar analysis of the amount of cannabis and heroin consumed in the city.

By Sam Bond

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