A bill raising the age of purchase for tobacco and vaping products from 18 to 21 has now been signed into law. 

Gov. Inslee signed the bill at 3 p.m. on Friday, after it passed both the Washington state House and Senate, and is expected to become law soon. 

The new Washington state law will go into effect on New Year's Day of 2020.

"#Tobacco21 is the most preventative, cost-effective policy we can adopt to protect the health of our youth. Trudi and I have supported this bill for years – and I look forward to signing it," Inslee said in a tweet, before he signed the bill.

Washington is now the tenth state to raise the age. Hawaii was the first to do so. Oregon and California are also in that group. Hundreds of cities, including New York and Chicago, have passed similar laws, too.

Increasing the smoking and vaping age has long been one of the core proposals of advocates for reducing teen smoking.

Such laws are fairly new, so hard data on effectiveness is limited.

However, one study of California's policy suggested that state's law did reduce underage tobacco purchases.

Surveys in Chicago and New York City also showed decreases in high school smoking rates after similar laws, supplemented by other anti-tobacco measures, were passed there.

One of the main arguments for raising the age: younger teenagers who smoke or vape usually get their products from a friend, and high school students are far more likely to have an 18-year-old friend than a 21-year-old friend.

But some people, including Joey Blodgett who runs Sublime Vapor in Spokane, say that while they want to keep tobacco out of schools, laws like this one go too far.

"There's pluses and there's minuses. I'd personally rather see it go to age 19 not 21," said Blodgett.

He argues there could be unintended consequences of creating new restrictions.

"Once you demonize something, kids want to do it," he said. "We've all been teenagers. We know what it's like. Don't do this? Oh, I'm going to do it."

He also said the effectiveness could be questionable in border cities like Spokane.

"I think it's definitely going to create a black market between that 18 to 21 group, and I think Idaho's going to get slaughtered with kids coming over there," Blodgett said.

Blodgett fears the new restrictions could do more harm than good.

"I think they need to leave small business out of it," he said.

But he's not worried about the long-term effect to his sales.

"We have a lot of people that are above the age of 21, so it's going to hurt a little bit but not necessarily probably too much," Blodgett added.

Blodgett also said that, as often happens when gun control measures are on the table, the new restrictions could cause a lot of people to start stocking up on tobacco products.

"I think we'll see a massive spike. Massive spike," he said.