Almost one month after a new state law raised the legal smoking age in California from 18 to 21, local tobacco product retailers are coming to grips with what the change means for their businesses.

“We are noticing an impact,” said Josh Sundberg, manager of E-Cig 101.

Located on Old Sonoma Road in the Carneros Center complex, the store sells dozens of flavors or scents of liquids containing nicotine. It also sells electronic cigarette, or e-cigarette, products.

Sundberg said business has dipped more than 15 percent since the legal age was raised.

“It’s a bit of a struggle,” he said. “We lost a bunch of customers” and sales are down compared to three or four months ago.

Purchases of vaping liquid make up about 80 percent of the store’s sales, said Sundberg.

E-cigarettes or other “vaping” products heat and vaporize the flavored liquid, which the user inhales. The nicotine-infused vapor of e-cigarettes looks like smoke but doesn’t contain all the chemicals, tar or odor of regular cigarettes.

If such a decline in sales continues to hurt the bottom line, “we could rethink keeping the store open,” he said. E-Cig 101 also has a store in Rohnert Park.

In addition to the new law, which went into effect on June 9, there’s another problem, said Sundberg.

Effective Aug. 8, the U.S. Food and Drug Administration (FDA) will start regulating all tobacco products, including e-cigarettes, cigars, and hookah and pipe tobacco, as part of its goal to improve public health.

This will allow the FDA to evaluate factors such as ingredients, product design and health risks, as well as products’ appeal to youth and non-users, said the FDA website.

According to the FDA, more than 3 million middle and high school students were current users of e-cigarettes in 2015, up from an estimated 2.46 million in 2014.

Sixteen percent of high school and 5.3 percent of middle school students were current users of e-cigarettes in 2015, making e-cigarettes the most commonly used tobacco product among youth for the second consecutive year, the FDA said.

With the new regulation, even “mom and pop” shop owners that mix or prepare liquid nicotine in house must now comply with all of the legal requirements for tobacco product manufacturers.

Sundberg said that smaller vaping liquid manufacturers who can’t afford the estimated $1 million to undergo FDA testing and authorization of each liquid nicotine product may have to shut down.

Larger manufacturers could buy out others or consolidate production, meaning prices for the liquids “could go up astronomically,” he noted.

Robert Gomez, an employee at Cal E-Cigs on W. Imola Avenue in Napa, said that his 18- to under-21-year-old customers are “kind of upset” that they can’t buy tobacco products at the store anymore.

Gomez explained that now that the rules have changed, he’s quick to ask customers entering the store if they are 21.

If not, “they just turn right around,” he said. Since the word got out, “the 18- to 21-year-old guys stopped coming around.”

However, Gomez said that he doesn’t think the store has seen much of a difference in sales since the new law was enacted. Many of his customers are older, he noted.

“They didn’t pay too much attention” to the age change.

There’s no mistaking the new rule at the Mighty Quinn Smoke Shop on Soscol Avenue.

“If you look under 30 years of age please HAVE YOUR GOVERNMENT ISSUED I.D. READY!” reads a new sign on the front door.

John Hurley, longtime general manager of the Mighty Quinn smoke shop chain, said he doesn’t think the new age requirement has impacted the business very much. However, it’s too early to say one way or the other, he said.

The new FDA regulations for vaping liquid may affect manufacturers and distributors “but by the time it gets to us the dust will be settled,” he said.

He didn’t want to speculate how the price for such liquid could change. If anything, the FDA requirements “will probably increase the quality of the product.”

Unlike other local tobacco product shops, the Mighty Quinn will sell tobacco and tobacco products to those with a military ID who are age 18 or older.

“That’s one exception,” that the law allows, he noted.

When asked why other smoke shops seemed to be sticking to the 21 and older rule no matter what, Hurley said those shop owners may not be aware of such an exception or “they’re erring on the side of caution.”

In January, the city of American Canyon voted to ban smoke shops or tobacco stores. According to an employee at AC Food And Liquor in American Canyon, since the new age law went into effect, the store has seen a decrease in 18- to 21-year-old tobacco shoppers. Cigarette and tobacco products are not selling as much, said the staffer, who declined to give his name.

The liquor store is getting rid of their already limited supply of e-cigarette and vaping products, he said.

They carried more of these products in the past, but found they weren’t selling enough so they’re phasing out that inventory. The staffer expects the change in federal rules will decrease sales for e-cigarette and vaping products for other businesses.

Bill Shaw, owner of Calistoga’s Cal Mart, said that tobacco sales at his market are about the same.

“We don’t sell a lot of cigarettes anyway,” said Shaw. The biggest change is that employees card more people than before, he said.

Noel Brinkerhoff of the American Canyon Eagle, Anne Ward Ernst of the Weekly Calistogan and the Associated Press contributed to this story.