How filthy is your favourite e-bike? As popularity surges, Daily Mail tests the handlebars of Lime Bikes, Boris Bikes, and Forest Bikes - with some containing traces of faecal matter

Every day, more than 100,000 Londoners hop on rental e–bikes to make their daily commutes across the capital.

But how many of them ever think about what might be lurking on the handles of their favourite bike?

The Daily Mail has taken to the streets with bacterial sampling swabs to find out exactly how dirty the handles of Britain's favourite bikes really are.

And the results might make you want to pack some hand sanitiser next time you set out for a cycle.

We used sampling swabs to gather up any bacteria that might have been growing on the handles of the most popular bikes: Forest, Lime, Voi, and the classic Santander Bike, also known as the Boris Bike.

According to our tests, the average rental bike handle could be covered with more than 100 times as many germs as a toilet seat.

Meanwhile, the worst offender was 418 times dirtier than the toilet in the office bathroom.

As if that wasn't off–putting enough, our testing even found bacteria that indicate recent 'faecal matter contamination'.

The Daily Mail has taken the streets with bacterial sampling swabs to find out exactly how dirty the handles of Britain's favourite bikes really are

Since Lime launched its first bikes in the UK in 2018, the popularity of rental e–bikes has exploded.

Now found in almost every major city across the UK, these fast, convenient and relatively cheap modes of transport have become a firm favourite.

In London alone, TfL estimates that 10 per cent of the 1.5 million cycle journeys made in the capital every day are on some sort of rental.

However, with so many people touching them every day, it's almost inevitable that their handles would become a magnet for germs and fungi.

To see just how dirty some of London's bikes really are, we used a technique called surface–swab enumeration testing, which gives an indication of the overall number of bacteria present on a surface.

We used a sterile swab to take a sample of the bacteria on the handles and sent that off to a professional lab.

There, the germs were transferred onto a Petri dish and incubated at 32.5°C for three days.

Scientists then counted how many patches of bacteria had grown, with each visible 'colony' representing a live bacterium or cluster of germs that was on the bike, giving a score called the aerobic colony count.

To see just how dirty some of London's bikes really are, we used a technique called surface–swab enumeration testing, which gives an indicator of the overall number of bacteria present on a surface

What bacteria were found on rental e–bike handles?

• Staphylococcus aureus: Indicates skin bacteria contamination and may cause infections.
• E.coli: Indicates recent faecal matter contamination and may cause food poisoning 
• Faecal Streptococci: Also indicates faecal matter contamination and may lead to mild infections  

We also took a swab to the toilet seat in the gents' toilet to put some of these results in context.

The very cleanest bike we tested was from the brand VOI, one of the less common types of bike, which had an aerobic colony count of 1,010.

However, every other bike tested had significantly more bacteria lurking on the handlebars.

The next dirtiest bike we tested was a Santander Bike, better known as a Boris Bike, with an aerobic colony count of 2,700,000.

That is 27 times dirtier than the VOI we swabbed and over six times greater than the toilet seat.

However, even that was still relatively clean compared to the worst offenders.

The Lime bike we swabbed was found to have an aerobic colony count of 60.6 million, over 140 times greater than we found on the toilet.

Meanwhile, the dirtiest bike of all was a Forest bike, with an overall aerobic colony count of 180 million – 418 times greater than that found on the toilet.

The dirtiest bike we tested had over 400 times more bacteria than a toilet seat, and was found to have evidence of 'faecal contamination' 

Dawn Mellors, technical director of Melbec Microbiology, the lab we contracted for the tests, said that this could be because the bike was 'more heavily contaminated', but cautioned that other factors 'need to be reviewed'.

Ms Mellors adds: 'If some of the bikes had not been used recently and the temperatures were high, any organisms on the surface would start to die off and hence numbers would look lower.'

The Forest bike was also the only rental for which the lab was able to isolate specific bacteria.

This does not mean that Forest bikes are dirtier, but rather likely reflects the fact that very hot weather and postage delays meant some bacteria in our samples may have died before reaching the lab.

However, even these limited results paint a rather grim picture of what might be waiting on the handles of any given rental bike.

The lab found over 1.3 million colonies of a bacterium called Staphylococcus aureus, the bacterium that causes staph infections.

Ms Mellors says that this is usually an indication of skin bacteria and, while usually relatively harmless, is classified as a pathogen and can cause infection if it enters the body.

More worryingly, our tests also revealed the presence of Faecal streptococci and E. coli in considerably high numbers.

The news may not come as a surprise to many commuters, who have taken to social media to complain about dirty e–bikes 

How dirty are London's rental bikes?

Results given in colony forming units, an indicator of the overall number of bacteria present.

Forest Bike: 180,000,000 cfu

Lime Bike: 60,600,000 cfu

Santander Bike: 2,700,000 cfu

VOI: 1,010 cfu

Toilet Seat: 430,000 cfu

Not only can these pathogens cause infections and food poisoning, but they are also indicators of 'faecal contamination'.

'This contamination could be from humans, but it could also be from animals, e.g. bird droppings,' says Ms Mellors.

'These organisms do not survive long in the environment so they usually indicate a recent contamination.'

This is in line with the results of a previous study of 50 e–bikes across London, which found that many of the rentals were 'riddled' with germs.

The tests, conducted by Initial Washroom Hygiene, revealed high levels of biological residue from skin cells, sweat, saliva, food residue – and in some cases, faecal matter.

It is worth pointing out that our results are not meant to be on a par with peer–reviewed scientific research and have a very small sample size of just one bike per brand.

That means it isn't the case that every Forest bike will be filthy, nor that every VOI is guaranteed to be clean.

What these tests do show, however, is that you might need to think carefully about your personal hygiene when you jump on a bike from any brand.

Although these tests had a limited sample size, they show that bikes can be a source of pathogens and that people should carefully wash their hands after use 

Ms Mellors says: 'The results of the study indicate that bike handles can be a source of pathogens and hence the handles should be efficiently disinfected prior to use or hands should be washed after using the bikes.'

According to Lime, the company's bikes are washed regularly, but members of the public should still wash their hands after use.

A TfL spokesperson said: 'The findings shared with us relate to a very limited sample and do not appear to show the presence of E. coli, faecal streptococci or Staphylococcus on the Santander Cycles sample that was tested.

'As with any frequently touched public surface, cycle handlebars can naturally carry environmental bacteria. We encourage all customers to maintain good hand hygiene and to wash or sanitise their hands after completing a journey where possible.

'Common touch points on our bikes, including handlebars, receive regular cleaning as part of our programme of maintenance and servicing to ensure every ride is safe and comfortable.'

A Voi spokesperson said: 'Any frequently touched public surface, from door handles to tube poles to shopping trolleys, will carry some level of bacteria – that's true of shared public life generally, not something particular to rental bikes.

'We take vehicle hygiene seriously and will continue to do so, but this data doesn't support the idea that Voi bikes pose a particular hygiene risk.'

Lime and Forest declined the Daily Mail's request to provide a comment on our findings.