Blowing vapor from an e-cigarette at a San Francisco lounge. Photo: Justin Sullivan/Getty Images

More adults may be giving e-cigarettes a try, but fewer people are making it a habit, according to research published in Journal of the American Medical Association Tuesday.

Why it matters: E-cigarettes often contain the addictive ingredient nicotine and other substances that the Surgeon General says may be dangerous, particularly to young people. Non-smoking advocates say the prevalence drop is encouraging, but the government still needs to mandate further research and curb teenage usage.

Context: E-cigarettes are widely marketed for smoking cessation (although its effectiveness remains uncertain). However, reports of growing illegal use by young people has caused alarm, and the decision by the Food and Drug Administration to delay its review to 2022 brought a March 27 lawsuit by anti-smoking groups.

"Nicotine has adverse effects on cardiovascular system; specifically, it increases heart rate and blood pressure and induces abnormal heart rhythms... it increases the risk of adverse pregnancy outcomes, and it crosses the placenta and negatively affects fetal brain development."
— Study author Wei Bao, of the University of Iowa, tells Axios

By the numbers: The research published Tuesday is an analysis of National Health Interview Survey data on e-cigarette use by U.S. adults in 2014–2016. Out of the roughly 32,000–37,000 people they surveyed each year, they found:

  • The number of people who tried e-cigarettes grew — 12.6% in 2014, 13.9% in 2015 and 15.3% in 2016.
  • But, the number who kept using e-cigarettes kept dropping — 3.7% in 2014, 3.5% in 2015, and 3.2% in 2016.
"The decline in current use but increase in ever use in e-cigarettes may suggest that some individuals are trying but not continuing use of e-cigarettes. However, it might be too soon to draw e-cigarette usage trends from just three years of data," Bao says.

Meanwhile, a separate survey by the Centers for Disease Control and Prevention last year, also found that there was a decline in 2016 in usage by youth (2011–2015 had seen a 900% increase in use among high school students).

Yes, but: Dennis Henigan, VP for legal and regulatory affairs at the Campaign for Tobacco-Free Kids, says the lower rates of usage in youth may be due to Juul becoming such a strong brand (like ubering, Juuling has become its own verb) that kids don't think of it as being applicable to surveys on "e-cigarettes."

  • He pointed to a Truth Initiative survey that found 63% of Juul users don't realize all have nicotine in them — each cartridge contains an entire cigarette pack's worth of nicotine.

What FDA says: They cannot comment on the lawsuit (the agency's legal response in court is expected by May 29), but a spokesperson says the agency is concerned about the impact on youth and is taking some measures to make tobacco products less toxic and appealing, especially for youth.

Industry response:

  • Juul says it's implementing its recently announced comprehensive strategy to combat underage use of its products.
  • Tony Abboud, Vapor Technology Association executive director, tells Axios a decline in youth use is a “top priority" for VTA.
  • As for adult use, he says: "Given the misinformation and fear tactics employed by so-called U.S. public health groups, it should not be surprising that some smokers are being scared away from e-cigarettes."

Go deeper:

  • This piece sums up the lawsuit against the FDA and some studies examining pod flavors.
  • The Washington Free Beacon reports on congressional Democrats circulating a petition to ban pod flavors like chocolate and cotton candy.
  • The New Yorker looks at the rise of Juul.

Editor's note: This piece updated the link and date for the CDC survey.

Go deeper

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 9 p.m. ET: 18,187,396 — Total deaths: 691,352 — Total recoveries — 10,841,436Map.
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  3. Politics: White House will require staff to undergo randomized coronavirus testing — Pelosi says Birx "enabled" Trump on misinformation.
  4. Sports: 13 members of St. Louis Cardinals test positive, prompting MLB to cancel Tigers series — Former FDA chief says MLB outbreaks should be warning sign for schools.
  5. 1 🎥 thing: "Tenet" may be the first major film to get a global pandemic release.

In photos: Thousands evacuated as Southern California fire grows

A plane makes a retardant drop on a ridge at the Apple Fire north of Banning in Riverside County, which "doubled in size" Saturday, per KTLA. Robert Gauthier / Los Angeles Times via Getty Images

A massive wildfire that prompted mandatory evacuations in Southern California over the weekend burned 26,450 acres and was 5% contained by Monday afternoon, the California Department of Forestry and Fire Protection said.

The big picture: As California remains an epicenter of the coronavirus pandemic in the U.S., some 15 separate fires are raging across the state. About 7,800 people were under evacuation orders from the Apple Fire, about 75 miles east of Los Angeles, as hundreds of firefighters battled the blaze. CalFire said Monday that a malfunction involving a "diesel-fueled vehicle emitting burning carbon from the exhaust system" started the Apple Fire.

Twitter faces FTC fine of up to $250 million over alleged privacy violations

Photo: Rafael Henrique/SOPA Images/LightRocket

The Federal Trade Commission has accused Twitter of using phone numbers and emails from its users to make targeted ads between 2013 and 2019, Twitter said in an SEC filing published Monday.

Why it matters: Twitter estimates that the FTC's draft complaint, which was sent a few days after its Q2 earnings report, could cost the company between $150 million and $250 million. The complaint is unrelated to the recent Twitter hack involving a bitcoin scam.