A journalist has drug tested House of Commons toilets and locations frequented by MPs and found traces of cocaine in almost half of them.

Vice reporter Michael Segalov took “coke swabs” – which turn blue when they detect the drug – and tested them out on nine locations across the Houses of Parliament, and four came up for cocaine residue.

One of these places was the Norman Shaw North, a building of offices for MPs; traces of cocaine were found in the sinks in a men’s bathroom on the third floor, where he used the swab and it turned blue, an indication, according to the journalist, that cocaine was present on the surface.

In the same building on the second floor bathroom, another swab turned blue, though it was “less concentrated.”

Toilets in The Woolsack (a social club) showed “small traces” of cocaine and toilets near the Strangers’ Bar, accessible to any parliamentary passholders, MPs, visitors who attend functions and events, public officials and journalists, showed “a huge amount of cocaine residue.”

The disabled toilets outside The Woolsack, and two other bathrooms outside of MPs offices also tested positive.

The news comes after a whirlwind Tory leadership contest campaign had several contenders admit to taking illegal drugs in the past.

Michael Gove admitted to taking cocaine on “several occasions” at social gatherings when was a young journalist.

He told the Daily Mail:

"I took drugs on several occasions at social events more than 20 years ago.

At the time I was a young journalist. It was a mistake. I look back and think, ‘I wish I hadn’t done that’. It was 20 years ago and, yes, it was a mistake. But I don’t believe that past mistakes disqualify you.

Andrea Leadsom admitted to smoking cannabis while at university in remarks made to The Independent.

“I have never taken cocaine or Class A drugs,” she told The Independent.

Everyone is entitled to a private life before becoming an MP. I smoked weed at university and have never smoked it again since.

Esther McVey McVey told ITV that she has never taken class A drugs but she has "tried some pot."

I have never taken any class A drugs, but have I tried some pot? Yes I have. When I was much younger.

Rory Stewart told the Telegraph he smoked opium in Afghanistan at a wedding.

I was invited into the house, the opium pipe was passed around at a wedding.

Matt Hancock reportedly "tried cannabis a few times"

A source close to Matt Hancock told the Telegraph he had "tried cannabis a few times as a student but has not taken any illicit drugs since."

Dominic Raab previously admitted to trying cannabis in university

“At university, I tried cannabis, not very often as I was into sport. It was a mistake, particularly the more I know now about the link between it and mental health issues."

But it was a long time ago and was particularly few and far between and I have never taken cocaine or any class A drugs.

Jeremy Hunt had cannabis lassi backpacking through India

He told The Times:

think I had a cannabis lassi when I went backpacking through India. That is almost as naughty as wheat fields.

Boris Johnson said he accidentally took cocaine, "I sneezed and it went up my nose"

Appearing on the BBC’s Have I Got News For You in 2005, Mr Johnson admitted being given the drug but joked that he had not actually taken it.

I sneezed and so it did not go up my nose. In fact, I may have been doing icing sugar.

Though he admitted to taking the drug when he was 19 in an interview with Marie Claire in 2008, a statement delivered after said it was "simply untrue."