The Mystery of What Happened to Plutonium Scandal Whistleblower Karen Silkwood

In 1974, Karen Silkwood left a union meeting in Oklahoma and headed out to meet a New York Times reporter at a nearby Holiday Inn. Minutes later, she died as her car crashed into a concrete ditch on the far side of Highway 74.

Silkwood worked at the Oklahoma plutonium factory at the time, where she noticed unsafe conditions were being ignored by the owners of the plant, the Kerr-McGee Corporation. She worked as a spy for her union and was collecting evidence of these unsafe oversights. The folder of evidence she carried the night of her death was never found. Here's what we know about what happened to her.

Silkwood said that the plutonium plant "strayed so far from the federal nuclear code that it posed a danger to its workers and the public," according to an article Rolling Stone published in 1977. Two former heads of the Kerr-McGee corporation eventually backed up Silkwood's claims of negligence on behalf of the company.

Silkwood reported dangerous conditions at the plant, including leaky pipes and broken equipment. Even when workers were being contaminated with plutonium, the company told them to continue working with faulty machines until demand waned, Silkwood claimed, according to Rolling Stone.

She claimed that the company was fudging quality reports and putting young, under-trained employees at risk of contamination.

Silkwood reported that the company shipped waste in unfit containers, which leaked and contaminated areas where it was buried.

Additionally, as many as 50 pounds of plutonium, enough for four nuclear bombs, went missing. Some believe Silkwood unintentionally discovered a smuggling ring during her investigation into the plant and the missing plutonium.

Before the car crash, Karen believed that she'd been contaminated with plutonium, according to Good Morning America. She wrote, "I have no knowledge of what happened, but I feel the contamination is coming out from my body." She said she was contaminated as she started investigating.

When she was tested, it seemed that her samples had been "intentionally spiked." While the union argued that someone may have contaminated Silkwood or spiked her tests, the company floated the idea that she contaminated herself for leverage in union negotiations, per GMA.

Other tests found "permissible levels" of plutonium in her lungs.

When Silkwood was encouraged to leave the plant for fear of her own safety, she said, "Oh, I'll be gone. … But I'm gonna shut them down before I go."

The night she died, she was carrying a folder full of evidence to a meeting with a New York Times reporter. A few minutes into her drive, her car veered across the two-lane highway, resulting in the fatal crash.

At the time of the crash, authorities said that Silkwood's tire tracks showed that she'd been unconscious and didn't have control of the wheel at the time of impact. An anxiety medication, a sedative, was found in her purse, further pointing to this theory. However, the steering wheel told a different story: that she'd braced for impact and couldn't have been asleep.

In 1992, a state trooper disclosed that off-duty Oklahoma City officers had followed Silkwood the night she died, and may have "bumped" her car as she drove, according to GMA.