Warning: Hand santitiser could EXPLODE if left in hot cars – and the heat will almost certainly render it useless

As the coronavirus pandemic has swept across the world, millions of people have stocked up on hand sanitiser in a bid to guard against the disease. 

But experts have warned that leaving it in a hot car could render it less effective because its active ingredient - alcohol - could evaporate. 

Bottles of hand sanitiser have also been known to explode after being left in hot cars. 

And Ford engineers also warned that hand sanitiser is likely to damage your car's interior.

On Wednesday, thousands of Britons crammed onto packed beaches to bask in 82F (28C) sunshine on what was the hottest day of the year so far, prompting reports that traffic wardens had even run out of tickets. 

Experts have warned that leaving it in a hot car could render it less effective because its active ingredient - alcohol - could evaporate

And the thousands of people who took to the roads to take advantage of the weather are likely to have taken hand sanitiser with them. 

But Dr Greg Boyce, an Associate Professor at Florida Gold Coast University in the US who worked in the department of chemistry and physics, said leaving bottles of the product in cars would not be a good idea. 

He told ABC News: 'If you are running errands and want to keep it in the car, that's fine. But you shouldn't be leaving it in the car indefinitely.

'It's definitely an issue if you leave your hand sanitizer in the car for days at a time or weeks. 

A car parked in direct sunlight can get as hot as 113F (45 Celsius) inside when outside temperatures reach 70F (21 Celsius), according to heatkills.org.

And Dr Boyce added that hand sanitiser could be less effective if its alcohol content diminishes. 

On Wednesday, thousands of Britons crammed onto packed beaches to bask in 82F (28C) sunshine on what was the hottest day of the year so far, prompting reports that traffic wardens had even run out of tickets

'Over a longer period of time at higher temperatures, you lose some efficacy in a hand sanitizer because the active ingredient evaporates,' he said.

Car mechanics also warned that hand sanitiser can damage the interiors of vehicles, according to motoringresearch.com. 

Ford engineers tested cars at extreme temperatures to replicate when they are left outside in hot weather. 

They found 'particularly high wear' on cars tested in Turkey and traced the damage to ethanol - the type of alcohol seen in most hand sanitisers. 

Mark Montgomery, senior materials engineer at Ford's Material Technology Centre, said: 'There were instances of particularly high wear in Turkey. 

'We managed to trace it back to ethanol potentially being a contributing factor, and most likely a popular hand sanitiser that contained 80 percent ethanol. 

'That's far higher than anything we'd seen before. 

'Even the most innocuous seeming product can cause problems when they come into contact with surfaces hundreds of times a year,' he added. 

In April, a mother warned of the hidden dangers of hand gels after a bottle of hand sanitiser which had been left in a hot car exploded.  

Alex Chadwick claimed the bottle of gel exploded when her daughter Olivia-Layla, 11, opened its cap, showering her left eye. 

The mother, from Baxenden, Lancashire, had been picking up a prescription from the pharmacy when her daughter was injured.