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ER doctors question the safety of electric bikes and scooters

A lot of vehicles that used to only run on human power have been electrified: bikes, scooters and skateboards. Their offer of greater speed and ease of use has encouraged travelers and environmentalists to reduce their reliance on gas-powered cars. But are they safe? KPBS sci-tech reporter Thomas Fudge has the story.

Chloe Lauer shows off her electric bike in a downtown park. She points out the video screen that displays the battery charge and the tools that operate the bike’s motor.

“So this is a full battery. This shows you how fast you’re going. And this is the pedal assist,” said Lauer, the executive director of the San Diego County Bicycle Coalition.

Electric bikes can be peddled like a regular bike. They can also run solely on their motor or help pedal, giving the rider's leg power a motorized boost.


Some cyclists have called electric bikes a game changer, Lauer agrees.

“We love e-bikes because it’s getting more cyclists on the road ... we want to expand cycling as a mainstream thing. The more people, the more mainstream it is,” she said.

A lot of vehicles that used to only run on human power have been electrified, and that includes bikes, scooters and skateboards. They offer great speed and ease of use and encourages commuters and environmentalists to reduce their reliance on gas-powered cars.

Nationwide, transportation accounts for 30% of all greenhouse emission. In San Diego, it’s even more — about 50%.

But the move to electrify bikes and scooters has raised concerns among people in emergency medicine.


Dr. Vishal Bansal is Chief of Trauma at Scripps Mercy Hospital and has seen a lot of accidents linked to motorized scooters, which are commonly available on the street for rent.

“You can pick one up anytime and start driving it,” Bansal said. “... and no one is wearing a helmet. At least I haven’t seen that when I’m seeing these people in town.”

UC San Diego did a study of just over 100 hospital admissions related to motorized scooters in 2017 and 2018. They found a dramatic monthly increase in admissions during that time period, with a wide variety of injuries.

That’s something Bansal can vouch for.

“We do see a fair amount of head injuries. Head injuries can be mild, moderate or severe. The majority are luckily on the mild or moderate side. But we have had some severe head injuries and death from head injuries from these vehicles,” Bansal said, adding that wrist and rib fractures are also common.

And what about e-bikes? Bansal said he’s concerned about their speed of travel, and he sees a lot of kids riding them unsafely.

“Basically at this point, they’re like motorcycles but they're not regulated in the same sense as motorcycles,” he said.

My traumatic encounter with a car

To me, this subject is personal. Years ago, in San Diego, I was hit by a car while riding my bike to work. I suffered a traumatic brain injury and ended up in the Scripps Mercy trauma ward. It was three months before I was well enough to return to work.

I know how dangerous it can be to ride in an unprotected vehicle on a road full of cars.

“When you do have that interplay when you have bicyclists right next to cars, you’re putting a tank next to these itty-bitty sticks and someone in their itty-bitty helmet! So it’s sort of a formidable task to go biking on our regular streets,” said emergency physician Dr. Elizabeth Barreras-rivest.

In the emergency room, Barrreras-rivest said she sees the worst results of that mismatched vehicular traffic. But she’s also a member of the health advisory committee of San Diego’s Climate Action Campaign.

She says the health risks of climate change are severe and numerous and they include asthma, heat stroke and premature birth.

The UCSD study on e-scooters describes those vehicles as inherently dangerous, combining “the size of a child’s push-scooter with the speed of an electric bicycle.”

Barreras-rivest argues they’re level of safety depends on the user.

“The same as anything else. You have to take control of your own personal safety. And if they’re treated as a toy, then certainly they are not a safe modality,” she said.

At San Diego State University, racks of e-scooters are available for rent. You see them zipping past pedestrians on sidewalks and bike paths. Cesar Jimenez bought his own, which he drives to school after he parks his car off campus.

I asked if he feels unsafe on the roads.

“No I don’t, to be honest,” Jimenez said. “Not really. There are certain areas of San Diego that — definitely — I think it would be nice to have those spaces for bikes or scooters. There are some places that do, and I think we can get better at it.”

Another student, who didn’t have a car, said she commutes to campus on her e-scooter.

“When I go in the bike lane — which we’re technically supposed to do — it really doesn’t feel safe at all. Cars don’t care about your safety,” Robin Kaminsky said.

But with new electric cars going for more than $60,000 a pop, Barreras-rivest said finding an affordable global-friendly way to travel may depend on bikes, scooters and the like.

“I think we face a choice where we either have to make some sacrifices to be environmentally friendly, or we face the greatest existential threat to humans,” she said.

Bansal’s view that e-bikes are not much different from motorcycles is not held by all. Lauer said Class 2 e-bikes have a maximum pedal assist speed of 20 mph. A Class 3 e-bike has a 28 mph maximum.

A normal bike can go faster than that on a downhill slope.

KPBS has created a public safety coverage policy to guide decisions on what stories we prioritize, as well as whose narratives we need to include to tell complete stories that best serve our audiences. This policy was shaped through months of training with the Poynter Institute and feedback from the community. You can read the full policy here.