Almost half of the people who followed Juul Labs Inc on Twitter were not old enough to legally purchase e-cigarettes in the United States, according a study published on Monday.

Researchers analyzed data collected in April 2018 on all public followers of Juul’s Twitter account (@JUULvapor) with at least one public tweet. About 45 percent of the individuals who followed Juul were 13 to 17 years old, according to the study in JAMA Pediatrics, published online on Monday.

In the study, only 19 percent of Juul’s Twitter followers were at least 21. These findings from more than a year ago may not reflect what is happening on social media today.

The study also was not a controlled experiment designed to prove whether or how following Juul on social media directly impacts vaping habits. Other research has linked teen vaping to an increased risk of smoking traditional cigarettes.

In an effort to curb teen vaping, the FDA in March proposed new age verification rules for retail and online sales of e-cigarettes in flavors like mango and cucumber that appeal predominantly to minors.

Juul also said in November that it would pull many flavors popular among teens from retail store shelves in an effort to reduce surging use of its products by young people.

The number of tweets about Juul rose dramatically from 2015 to 2017, corresponding with a sharp rise in Juul’s retail sales, researchers reported in JAMA Pediatrics.

Online conversations about Juul were rarely about smoking cessation; instead, they focused on how to use and purchase Juul devices, which look like a USB flash drive and vaporize a flavored liquid containing nicotine.

Reuters