The party may be over for e-cigarettes.

Regulations announced by the Food and Drug Administration in May went into effect on Monday, banning the sale of e-cigarettes and other tobacco products to minors and requiring all tobacco manufacturers — including e-cigarette companies — to submit products for premarket review. Products on the market before February 2007 will be permitted to circumvent FDA approval. Before these regulations, there was no federal oversight of the e-cigarette industry.

“The agency considered a number of factors in developing the rule and believes our approach is reasonable and balanced,” said Mitch Zeller, director of the FDA’s Center for Tobacco Products, in a statement.

See also: The FDA may soon be able to vaporize e-cigarette products

Little is known about the long-term health effects of e-cigarettes. And despite research that calls into question the effectiveness of e-cigarettes as a quitting mechanism for traditional cigarettes, the Royal College of Physicians in the U.K.—which published the first comprehensive report on the harms of smoking cigarettes in 1962—issued a report in late April stating that they are a viable alternative to other methods.

Since their introduction in 2007, e-cigarettes have become a booming industry, with an expected $1.5 billion in sales in 2015, nearly half of the estimated $3.5 billion in sales of all vaping products, according to Wells Fargo WFC, -4.33% . However, the popularity of the devices among teenagers has become a growing concern, with the number of high-school students reporting current e-cigarette use rising from 1.5% in 2011 to 16% in 2015, according to the Centers for Disease Control and Prevention. About 3 million middle and high-school students reported using the devices in 2015, according to the agency.

The new regulations are a concern for e-cigarette industry advocates, who say that premarket approval will cost small companies millions of dollars that they cannot afford, consolidating the industry to fewer products produced by major tobacco companies and giving consumers limited options. “If the FDA’s current approach is implemented, producers would be required to remove every single product from the market and submit expensive and burdensome applications for the chance to allow their products to stay on the market,” said Caroline Kitchens, a policy analyst at R Street, a public policy research firm that advocates for free markets, in a statement.

For each product to go through the premarket approval process, the FDA estimates it will take about 1,700 hours of labor, costing companies at least $1 million per product tested. Only one such product, Swedish Match, has entered into that approval process, says Arnaud Dumas de Rauly, treasurer of the Vapor Technology Association and president of e-liquid—the substance vaporized in e-cigarette devices—manufacturer Gaiatrend USA. “It’s going to cost time and it’s going to go nowhere,” Dumas de Rauly says. “It’s an antique process.”

The only companies expected to afford this compliance are tobacco companies like Altria MO, -2.56% and R.J. Reynolds US:RAI that can fund the testing with profits from traditional cigarette sales. “For big tobacco, this is pocket change to them,” says Gregory Conley, president of the American Vaping Association. “Other companies in the industry will be forced to sell out to investors or focus internationally.”

Altria is also concerned about the grandfather date for premarket approval, says Steve Callahan, a spokesperson for the company.

A Reynolds spokesman said the company supports the FDA’s efforts, saying, “Today starts a critical regulatory process to dramatically improve the public health of our country by reducing the death and disease caused by smoking.”

Aside from taking legal action, there is one other way e-cigarette producers may be spared from the costs of premarket approval. In April, the U.S. House Appropriations Committee passed an amendment to the Agriculture Appropriations bill with bipartisan support that would push the grandfather date for premarket approval to the date when the regulations take effect, allowing products currently on the market to stay there. The amendment would also restrict e-cigarette advertising and require product labeling, similar to requirements for traditional cigarettes.

“We want regulation, we just want it to be sensible and not put everyone out of business,” Dumas de Rauly says.