University of California San Diego researchers have found that a significant number of electronic scooter users who were seriously injured were under the influence of drugs and/or alcohol – and most were not wearing a helmet.

The study was published in Trauma Surgery & Acute Care Open.

Since 2017, the scooters — with cute names like Bird, Lime, Bolt, Sherpa and Spin — have been popping up in U.S. cities as a cheap form of transportation.

But, the popular mode of transportation hasn’t been well received everywhere.

Nashville, Virginia Beach and Chattanooga have recently banned or restricted the use of eScooters due to safety concerns. Atlanta instituted a nighttime ban after four riders in the area were killed in collisions with other vehicles.

eScooters are illegal on Pennsylvania roads. While state lawmakers are looking to change that, the City of Philadelphia said it would seek a ban citing safety concerns.

In the small California study, researchers looked at 103 admissions to three Level 1 trauma centers for eScooter-related injuries and whether the user was wearing a helmet or using drugs and alcohol . It did not look at those treated for minor injuries. They found that two-thirds of those injured were men, with 62% of them aged 20 to 40. Ninety-eight percent were not wearing a helmet when they were injured.

About 42% of the injuries involved fractures to the leg or ankle, collar bone, shoulder blades or forearm. About 18% of those injured had bleeding on the brain and 17 people had a concussion. About 26% of those injured had facial fractures, most of which were mild.

In all, about one-third of the group required surgery.

Substance use was present in most cases. Of the 79% who were tested for alcohol use, about half were over the legal limit of .08. Sixty percent were screened for drugs and half tested positive. The most common drugs found were cannabis, methamphetamine and amphetamines, researchers found.

“As the popularity of alternate modes of transportation continues to rise, eScooter related injuries are likely to increase as well,” researchers concluded.

This is not the first study to look at injuries suffered by eScooter users.

The Centers for Disease Control and Prevention looked at more than 936,000 eScooter trips taken in Austin, Texas from Sept. 5 through Nov. 30, 2018. Of the 190 injured scooter riders, half suffered a head injury and only one was wearing a helmet. Twenty-nine riders reported drinking alcohol in the 12 hours preceding their injury.