Three years after new tobacco license regulations went into effect, the density of tobacco retailers in Philadelphia has been reduced by 20%, according to a new study by the Philadelphia Department of Public Health.

That amounts to 659 fewer licensed tobacco retailers in Philadelphia, a city that has had the highest density of tobacco sellers compared with other major U.S. cities, according to the study, published Thursday in the American Journal of Public Health.

“This is impressive and incredibly important for Philadelphia’s health, especially for low-income neighborhoods that are disproportionately affected from tobacco being everywhere,” said study lead author Hannah Lawman, the health department’s director of research and evaluation for the division of chronic disease and injury prevention.

The regulations were intended to reduce tobacco use and to discourage children from picking up the habit — or at least make tobacco products less accessible to youngsters. They were adopted in 2016 and went into effect in 2017.

“Children on their way to school should not be bombarded with advertisements enticing them to start smoking,” city Health Commissioner Thomas A. Farley said when the new rules were adopted.

The regulations limited tobacco-selling permits to one retailer per 1,000 residents. At the time, the city’s overall tobacco retailer density was more than twice that, and even higher in many low-income neighborhoods.

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In addition, the rules created smoke-free zones that prohibit new tobacco retailers within 500 feet of school properties; increased the city licensing fee from $50 to $300 to fund the compliance program; and established the loss of tobacco sales privileges for repeated youth sales violations.

“Three years after implementation, an estimated 84,300 youths from over 200 schools in Philadelphia benefited from a reduction in tobacco retailers near their schools, including more than 10,500 youths who had their school zone exposure drop to zero,” the article states.

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According to the study, the citywide retailer density went from nearly 2 sellers per 1,000 residents in 2016 to 1.6 in 2019. In low-income neighborhoods, the rate dropped from 2.8 per 1,000 residents in 2016 to 2.2 in 2019. In more affluent areas, the rate decreased from 1.4 per 1,000 residents in 2016 to 1.2 per 1,000 in 2019.

The researchers studied data from more than 23,000 tobacco permits over eight years to assess the impact of the regulations.

Last month, city health officials announced their biggest crackdown so far on businesses selling tobacco products to children under age 18. In that enforcement action, 149 businesses will be barred from renewing their tobacco sales permits this year. The shops had been caught selling tobacco products to minors between three and seven times in two years, said city officials.

Some business owners, including members of a local 7-Eleven franchise owners group, have been critical of the regulations, arguing they hurt small business owners who don’t sell tobacco to kids and limit their ability to sell their businesses.

Philadelphia has the highest level of tobacco use of the 10 largest U.S. cities, and each year, smoking is responsible for over 3,500 deaths here, more than guns and opioids combined, say city officials.

Adults in Philly are more likely to smoke cigarettes than other Americans – at least 18% vs. 14% overall, according to city health data, and 17% of Philly’s young adults ages 18 to 34 use e-products.

Philly high school students have reported a huge drop in cigarette use — 2% reported smoking cigarettes in the prior 30 days in 2019 compared with 23% in 1999. But other forms of tobacco use are going strong, with 7% of local youth reporting using e-products and 4% using cigars, smokeless, and other tobacco products, according to the 2019 Youth Risk Behavior Survey data.