The St. Louis Secret Spraying Tests

I randomly overheard two older guys talking at work one day. One of them said, "You know the government sprayed my neighborhood when I was a kid." I thought he was joking.

He wasn't.

That sent me down a rabbit hole.

Back in the 1950s and 60s, the U.S. Army carried out a series of tests in cities across the country. One of the most talked about happened in St. Louis, Missouri.

Residents were told the military was testing smoke screens that could help protect cities during a Soviet attack.

Years later, declassified records showed they had actually been releasing zinc cadmium sulfide into the air to study how particles spread through urban environments.

The government maintained at the time that the material was considered safe in the amounts used.

But over the years, people started asking whether those assumptions were wrong.

Some researchers and residents questioned whether the tests could have contributed to long-term health problems, while others argued there isn't enough evidence to directly connect the experiments to specific illnesses.

That's what makes this one so creepy.

Nobody woke up that morning thinking they were part of a military experiment.

Kids were outside playing.

People were walking to work.

Families had no idea aircraft and equipment were being used to study how material moved through the neighborhoods they lived in.

Most people never even knew it happened until decades later.

Whether the material caused lasting harm is still debated.

The fact that the testing happened isn't.

The documents exist.

The government admitted the tests took place.

Whenever someone says, "If something like that happened, everyone would've known," I always think about this.

Sometimes people don't find out until 40 years later.

By then, the people who made the decision are gone, the records are archived, and the only thing left is a question nobody can answer anymore.