"Public Health Warning. Possible future site of a 5G small cell installation."

NY1 found dozens of fliers with this message posted all across Astoria, Queens, places like 30th Avenue, 31st Street and Ditmars Boulevard.  

5G is shorthand for Fifth Generation wireless technology. According to experts, it could be as much as 10 times faster than existing 4G connections.

The flier says 5G antennas are a source of constant radio frequency microwave radiation, and it claims studies have shown chronic exposure could cause cancer. It says more information is available at 5GCrisis.com.

"I do wonder who would be behind it. Someone must have a little incentive," a resident told us.

A recent New York Times report suggests that Russia is behind a long-running propaganda campaign raising questions about 5G, perhaps to get Democratic governments tied up in fights over the technology. Are the fliers part of this disinformation effort?

The link on the flyers led us to Doug Wood, who heads Americans for Responsible Technology. He says his group has nothing to do with the fliers, or with Russia, but he's not surprised people are questioning the potential impact of the technology.

"I think there are a lot of people who trying to raise awareness about this issue, because so many people don't know what 5G is," said Wood.

Wood says his science-based group is not being alarmist but believes the technology is too new to be thoroughly tested.

That's something Ted Rappaport, the director of NYU Wireless, disputes. He says he's been researching 5G frequencies since the 1990s.

"The frequencies we're using in cellular are 10,000 times weaker than the frequencies we know cause health effects. The people need to be more worried about putting on sunscreen to block ultraviolet radiation or getting too many x-rays or flying above 10,000 feet than they need to worry about wireless," said Rappaport.

The latest guidance from the National Cancer institution suggests there is no correlation between radiation from cellphone use and cancer. 

Reisdents we spoke with were curious about the mysterious warning, but most seemed unconcerned.

"If it's about cellphone towers, I'm not too worried about it. I have a cellphone in my pocket right now," said one resident.