Chemtrails are being put into the atmosphere and are trickling down into soil and water, becoming “the real cause of disease.”

A conspiracy theory about cloud formations in the sky does not seem like it’s fading into the night sky any time soon, even after two decades.

An April 21 Facebook reel showing intersecting line-shaped clouds in the sky says these normal emissions are dangerous.

“This is not contrails that are coming off of the back of an engine or back of the plane,” says the video’s narrator. “These are chemtrails — barium, strontium, aluminum, all kinds of pollutants that they’re putting into our atmosphere which comes down, trickles down, gets into our soil, gets into our water.”

The narrator said this is “poisoning” and “the real cause of disease,” but did not specify the kind of disease.

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

PolitiFact has debunked other claims involving “chemtrails.” The evidence remains: chemtrails aren’t real. 

A 2016 study evaluated claims of a secret large-scale atmospheric program, commonly referred to as “chemtrails” or “covert geoengineering.” The authors from Carnegie Science, University of California, Irvine and the nonprofit organization Near Zero surveyed atmospheric chemists who specialize in condensation trails and geochemists. 

Seventy-six of the 77 participating scientists agreed that evidence presented to support claims that atmospheric spraying occurs can be explained through other factors, including “typical airplane contrail formation and poor data sampling.”

Contrails — short for condensation trails — are “line-shaped clouds sometimes produced by aircraft engine exhaust,” as defined by experts at the Environmental Protection Agency, the Federal Aviation Administration, the National Oceanic and Atmospheric Administration and NASA. 

They are formed when water vapor in aircraft engine exhaust is released into low ambient temperatures that are common at high altitudes. The experts said contrails consist primarily of ice crystals and “do not pose health risks to humans.”

The U.S. Air Force called the chemtrail conspiracy a “hoax” and debunked claims of reported outbreaks of illness after the appearance of “chemtrails.”

“There is no such thing as a ‘Chemtrail’. Contrails are safe and are a natural phenomenon. They pose no health hazard of any kind,” it said.

We rate this claim Pants on Fire!