One in 10 people have traces of cocaine or heroin on their fingerprints - "Scientists have found that drugs are now so prevalent that 13 per cent of those taking part in a test were found to have traces of class A drugs on their fingerprints - despite never using them."

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One in 10 people have traces of cocaine or heroin on their fingerprints - "Scientists have found that drugs are now so prevalent that 13 per cent of those taking part in a test were found to have traces of class A drugs on their fingerprints - despite never using them."