Could Jenson Button's house have been gassed by burglars?

Jensen Button

It sounded to us like the perfect type of crime - knock everyone out with gas and rob the place.

French police are suggesting that's essentially what happened to Jenson Button at his rented villa in the French Riviera.

But doesn't it sound a bit too easy to be true?

The most common gases used to 'send people to sleep' are medical anaesthetics.

They are given to patients before surgery. Is that what was pumped into Jenson's bedroom?

Could I say it's absolutely impossible? I don't think I could
Dr Liam Brennan
Royal College of Anaesthetists

"Unlikely," says Dr Liam Brennan, Vice President of The Royal College of Anaesthetists.

He says for a medical anaesthetic to work in those circumstances you would need to administer it in "extremely large concentrations".

Before an operation, between 2%-10% of the air in a patients lungs is replaced by the anaesthetic.

Jessica Button
Image caption Jenson's wife Jessica had her engagement ring stolen.

With a mask over the nose and mouth, the body becomes a "closed circuit", which means there is practically no air escaping, allowing the levels of the gas to be controlled easily.

"To be able to deliver that in the much, much larger volume of a house or a room you would need truly industrial levels of those agents," Dr Brennan says.

Talking with Dr Brennan it becomes clear medical grade anaesthetics are not really cut out for use in a robbery.

A big problem seems to be ventilation.

To fill a house with the right percentage of anaesthetic would be incredibly difficult - a rogue open window in the bedroom could scupper the plan.

BUT... it's "not impossible" says Dr Brennan.

"If you asked me could I go and do that tomorrow - go and put a room full of people to sleep - I don't think I would be able to.

"I don't know how I would be able to deliver it and deliver it to a concentration that would be reliable - certainly reliable enough that I would chance walking into a room to rob something.

"Could I say it's absolutely impossible? I don't think I could say that, but I don't know how they would do it," he says.

It happens quite frequently
Hamish de Bretton-Gordon
Chemical weapons expert

He's also not aware of a particularly significant black-market for the buying and selling of strong anaesthetics.

So are there other types of 'sleeping gases' that could be used?

Well, yes.

And attacks on rich individuals like this are "not uncommon" according to security and chemical weapons expert Hamish de Bretton-Gordon from MD Avon Protection.

"It happens quite frequently" he says.

"High net worth individuals" have been targeted in the past in this way.

However "a lot of it's not reported" because, although they are rich, the victims are not famous.

Around a litre sized tin would be enough to knock out a room for about 10-20 mins

One example of such a gas is Fentanyl, says De-Bretton Gordon.

Fentanyl is a powerful painkiller but can also tranquilize.

It was famously used by Russian security forces during a hostage siege in 2002 and is still used by some armed forces.

"Around a litre sized tin would be enough to knock out a room for about 10-20 mins," Hamish offers as a rough guide.

That suggests criminals would at least be able to transport it easily.

However, it is difficult to get hold of and even if one could, it would be very difficult to administer and control.

Hamish says Fentanyl can be purchased on the Dark Web - a layer of the internet difficult for normal users to access but a modern home for illegal trading.

Apparently there is such a thing as "air conditioner security" because these types of attacks are "not rare".

I do remember one case in the UK

"It's more common on the continent and in eastern Europe," Hamish told Newsbeat, "but I do remember one case in the UK".

"That was a family dispute, rather than a burglary," he says, "but this kind of technique was used."

There have been reports of people in caravans being attacked in this way in the south of France.

Hamish says he knows of truck drivers in Europe who were targeted with carbon monoxide.

In those cases, criminals wanted to knock the driver out and steal the goods in the vehicle.

Jenson Button and wife Jessica

Carbon Monoxide is dangerous and can kill - so can Fentanyl, if the person breathing it in has underlying health issues (see the Russia siege again).

Some security forces around the world still use Fentanyl.

There is nothing yet to suggest it's exactly what was used to put Jenson Button to sleep.

But at the very least it seems the idea of a 'sleeping gas' is not so far fetched.

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