After a spate of illnesses linked to vaping, states are rushing to push through bans on e-cigarettes for anyone under 21. Governors are calling for prohibitions on flavors like bubble gum, cotton candy and banana split, which critics say are meant to entice young people into trying vaping. And in some states, lawmakers are contemplating raising taxes on vaping products as a way to discourage their use.
Yet amid the flood of new measures from state leaders as well as mayors, experts said it was uncertain how much immediate or lasting effect the provisions would have on a broad and growing range of concerns about vaping.
The source of the mysterious lung ailment that has been tied to seven deaths and hundreds of other illnesses in recent months is unknown, so state lawmakers and health experts acknowledged that they were aiming at a moving target with no assurance that new legislation can prevent future outbreaks.
And experts said the efforts by local leaders to limit vaping are further complicated because they create a state-by-state patchwork of rules and come as federal authorities say they, too, are moving forward with plans for additional oversight.
George W. Till, a Democratic state legislator in Vermont who is also a doctor, said that with few exceptions, the Food and Drug Administration — not a state or municipality — had the authority to decide what chemicals in vapes are permissible.
“I don’t think we have a lot of ability to control what comes through distributors, except to regulate the flavors and the packaging,” Dr. Till said.
Around the nation, most of the state and local proposals have been aimed at preventing young people from starting to vape, a process that usually involves exposure to nicotine, a substance that is particularly addictive to children.
But much of the state legislation fails to address black market e-cigarette products that health officials say appear to be at least partly responsible for some of the recent illnesses.
Dr. Steven A. Schroeder, a professor of health at the University of California, San Francisco, said state prohibitions against all flavored e-cigarettes were blunt approaches with significant limits.
“There’s a large group of well-intended public health experts who regard e-cigarettes as a huge public health problem,” he said. “And I think they have been opportunistic on seizing on this illness to ban all of these products without giving thought to the broader implications.”
The rush of activity comes after years of efforts by health groups like the American Lung Association to restrict the availability of e-cigarette products. Those efforts have suddenly gained momentum amid announcements about the series of lung-related deaths and illnesses that the authorities have tied to vaping.
During the past few weeks, state and local officials have repeatedly stepped into a rising public debate over vaping. Gov. Andrew M. Cuomo of New York and Mayor Lori Lightfoot of Chicago have called for bans on flavored e-cigarettes. This month, Michael R. Bloomberg, the former mayor of New York City, announced a $160 million campaign to ban flavored e-cigarettes in at least 20 cities and states. And California announced a public service effort on Monday to warn of the dangers of vaping.
Though the cause of the illness is not yet known, investigators for the Centers for Disease Control and Prevention have warned that a significant number of the sick patients used vaping liquid that contained a chemical called vitamin E acetate and THC, a psychoactive chemical derived from marijuana.
Studies show that young people’s use of e-cigarettes has escalated in recent years, with more than one in four children under 18 saying that they recently used an e-cigarette.
“The fact that you have that number of kids is just unacceptable,” said Erika Sward, assistant vice president for national advocacy for the American Lung Association. “And that is directly related to the flavors.”
Advocates for placing limits on e-cigarette sales say they intend to use strategies they gleaned from battles with the tobacco industry beginning in the 1980s.
A federal ban on flavored cigarettes in 2009, for example, led to a significant reduction in teenage smoking nationally and has become the model approach for many lawmakers.
“We know it will work because it worked in the past,” said John F. Keenan, a Democratic state senator in Massachusetts, who has introduced a bill outlawing flavored e-cigarettes.
Advocates have pushed for several new regulatory measures: a ban on advertisements designed to attract children; zoning restrictions limiting where e-cigarettes can be sold legally; and increased taxes on vaping products to match taxes on tobacco.
Studies have shown that price increases on tobacco products may have had the largest impact in reducing the tobacco smoking rate among young people, which has fallen to about 6 percent this year from nearly 16 percent in 2011.
In Arkansas, Asa Hutchinson, the Republican governor, said this week that he was open to calling a special legislative session to consider a bill to tax e-cigarette products at the same level as tobacco.
A similar bill failed this year, but Arkansas lawmakers said fears about the alarming lung disease and the prevalence of vaping among young people had shifted some views.
“We need to send a clear message to our young people that there are multiple health risks associated with vaping,” Mr. Hutchinson said in a statement.
This month, Michigan became the first state to prohibit sales of flavored e-cigarettes in stores and online. In June, San Francisco became the nation’s first major city to ban the sale and distribution of all e-cigarettes.
But Leo Beletsky, a professor of law and health sciences at Northeastern University, said outright bans on e-cigarettes — while well intentioned — might do as much harm as good because they are a far healthier alternative to cigarette smoking.
“The question is: ‘What is the problem here?’” Mr. Beletsky said. “To address a public policy question, you first have to diagnose the problem correctly, and these laws are a sweeping knee-jerk reaction to a fairly limited problem.”