How a Chemist and His ‘Poison Squad’ Inspired the First Food Safety Regulations

Author and science journalist Deborah Blum describes how an Indiana chemist kicked off the first major food regulation in the U.S.

Archival black and white photo of Union Stock Yards in Chicago, Illinois,

A buyer looking over cattle at the Union Stock Yards in Chicago, Ill. Photographed by John Vachon, U.S. Office of War Information/U.S. Farm Security Administration, July 1941.

Universal History Archive/Universal Images Group via Getty Images

It was common in the 1800s for people to consume milk containing formaldehyde, meat preserved with salicylic acid and borax, and “coffee” filled with ground up bones and charred lead.

The 19th century was largely unregulated, especially when it came to food. “Medical historians always call that period the century of the great American stomachache,” says Deborah Blum, a Pulitzer Prize–winning science journalist and author of the 2018 book The Poison Squad: One Chemist's Single-Minded Crusade for Food Safety at the Turn of the Twentieth Century.

Food adulteration and the use of harmful ingredients were not even illegal because there were no laws around food safety or purity in the U.S. It wasn’t until 1883 that a former Purdue University chemist, who had just become chief chemist of the U.S. Department of Agriculture, started investigating fraud involving foods and drinks: Harvey Washington Wiley and a small group of his colleagues experimented on young men who became known as the “poison squad.” The researchers exposed these men to various questionable foods and observed the effects. Wiley’s methods were somewhat unorthodox—by modern standards, perhaps unethical—but it was the first attempt to gather data for any sort of regulation of an industry that was sickening and killing many people.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Others aided the crusade for better food safety, including journalist and activist Upton Sinclair, author of the 1905 novel The Jungle, which famously exposed the horrific practices of the U.S. meat industry; food manufacturer Henry Heinz; and cookbook author Fannie Farmer. As a result of these efforts, in 1906 Congress finally passed the Federal Meat Inspection Act and the Pure Food and Drug Act, the latter of which became known as the “Wiley Act” and “Dr. Wiley’s law.” These laws contained strict regulations over the conditions under which meat was produced and eventually laid the groundwork for the creation of the Food and Drug Administration. The laws were not perfect, however, and there have been several attempts to refine these regulatory powers over the decades since.

Today the food industry continues to push back against federal regulation. Recently U.S. congressional representatives introduced the Food Traceability Enhancement Act, which would exempt food retailers from many of the rules the FDA uses to track outbreaks of foodborne illness. If the act passes, it could significantly impede the FDA’s ability to find the source of such outbreaks, which can be deadly.

Scientific American spoke with Blum about the history of food safety in the U.S. and the way that history continues to inform our relationship with food regulation today.

[An edited transcript of the interview follows.]

What was the status of food safety in the 19th century?

The U.S. was really slow to the food safety game. There were regulations in Europe and in Canada before we actually took this up. There was just an incredible amount of 19th-century U.S. resistance to the idea of the federal government, as someone said, becoming the “policeman” of your stomach. And so that whole American ethos of “nobody tells me what to do,” individual rights, all of those things really played into it, as well as enormous industry resistance.

Then along came Harvey Washington Wiley. How did he launch federal oversight of food in this country?

I describe him as a “crusading chemist”—I sometimes call him a “Holy Roller chemist”—who was absolutely passionate about the idea that we needed to do something to make the American food supply safer. He had been the first professor of chemistry at Purdue University at a time when it only had six faculty members, including the university’s president. He had studied deceptive food practices when he was in Indiana. And when he came to the federal government, he was head of what was then called the Bureau of Chemistry at the USDA. He launched the federal government, for the first time in its history, into looking at the idea of food safety and food integrity. There were people who did it at the state level, but at the national level, there was no scientist looking at it.

In 1883, when my guy Wiley arrives at the USDA, there are fewer than a dozen chemists at the agency. They’re responsible for all the agricultural chemistry issues in the U.S.—everything from pesticides to crop growth to soil quality. He tells them, Now we’re going to test the integrity of the American food supply. And they do it! Starting in the 1880s, this tiny group of chemists starts doing a series of reports that have the very boring title of “Bulletin 13.” And the chemists look at dairy, and they look at canned vegetables, and they look at coffee and tea, and they look at wine and beer and spices and processed meats. And they really take apart the processed, industrialized food system of the U.S. And across the board, they find really, really bad things.

What were some examples of the questionable food practices they found?

Some of it was just fraud. There was, like, 90 percent adulteration of spices. If you were buying cinnamon, you were buying brick dust. If you were buying pepper, you were buying dirt or charred and ground rope. If you were buying coffee, sometimes you were just buying ground shells. People would grind up bones and charred lead into coffee. If you got flour, you got gypsum. If you got milk, you got chalk or plaster of paris. And actual milk was full of horrible bacteria—there was no pasteurization; there was no refrigeration. People started putting preservatives such as formaldehyde in milk; the milk started killing people around the country. All of this was completely legal. No one could ever be prosecuted for any of this.

That’s pretty horrifying. What motivated Wiley to take action?

There’s no requirement to honestly label anything [at this time]. So you see Wiley starting to say, There are so many of these additives in food, such as formaldehyde and salicylic acid, which causes the lining of your stomach to bleed, and all these other things. Why can't we just tell people what’s in the food so they know how many times a day they’re eating these products? There’s absolute industry resistance to this. Nothing passes. Wiley goes to Congress. Nothing happens. In the entire 19th century, [hardly any] federal regulation regarding food safety or drink safety or drug safety gets through Congress, which is pretty much owned by industry at this point.

So what did Wiley do about it?

Wiley ran what the Washington Post called these “poison squad” experiments, in which he experimented with young workers at the USDA and put these different additives in their food and poisoned them, essentially. The whole science of epidemiology, the science of public health, is so in its infancy at this point. His poison squad experiments had a control group—he had two groups that all consumed the same foods and drinks, but one group got these additives, and one of them didn't. It’s super primitive to us today, but it was really forward-looking and kind of methodical. It was a completely illegal experiment by today’s standards; they’d be, like, running you out of town now.

But it wasn’t just Wiley and his poison squad, right? Weren’t there other people crusading for the cause of food safety at that time?

You have what was called the pure food movement. Wiley did a lot of talking to women’s groups. Women couldn’t vote at that time, but he thought they were very politically organized and powerful. So he went and worked with a lot of women’s groups who crusaded for the cause. He found some friendly manufacturers such as [Ketchup entrepreneur] Henry J. Heinz. And there’s this start of a push toward at least public recognition that food is unsafe. In the cookbooks of the time, you have cookbook writers such as Fannie Farmer saying, Okay, I’m going to tell you to put coffee in this recipe—just be aware that it’s not going to be coffee, or, You should not put milk in the food of sick people because it’s so dangerous.

Upton Sinclair, a socialist writer, writes this book, The Jungle. It was first published in the socialist newspaper Appeal to Reason as a call to arms about the plight of the worker. And he finally gets a New York City publisher to agree to publish it. Because he had gone and embedded himself in the stockyards of Chicago, he has all this incredible description about how horrible meat processing is and the mold that’s growing on the meat that still goes into the potted ham and the disease and the rotting animals that go into the sausage. The publisher sends fact-checkers to Chicago to make sure that this isn’t all just bullshit, and the fact-checkers come back, and they say, It’s even worse than he says. A copy was sent to President Theodore Roosevelt. The book becomes this big explosion. Nobody cares about the plight of the worker. There's that famous quote from Upton Sinclair, “I aimed for the public’s heart, and by accident I hit it in the stomach.”

So what did Roosevelt do about the situation? How did it lead to Congress passing food safety regulations?

There’s such a storm about The Jungle that Roosevelt sends his own fact-checkers to Chicago. And the crazy thing about that visit is that the meat-packers know they’re coming. The meat-packers clean up the stockyards. And these fact-checkers come back, and they also go, “It’s even worse than in the book.” Roosevelt then goes to Congress, which is entirely in the pocket of the meat industry, and says, I want a meat inspection act. If you don't give me a meat inspection act, I’m going to publish this report.

He ends up publishing about six to eight pages of this report, which was almost 100 pages. Those six pages are so explosive that every country in Europe cancels its meat contract with the U.S.. And at that point, the packing industry goes, Oh, my God, we’re going to have to have a meat inspection act. And so the Federal Meat Inspection Act goes through Congress.

What did the Federal Meat Inspection Act do?

The act has got a ton of teeth in it. The meat industry has to actually pay to help inspect the meat; the meat inspectors have real power in the factories. It’s got a lot of funding built in. There’s a powerful recall apparatus built into the meat inspection act. And in this kind of storm of legislative outrage over the food supply, the Pure Food and Drug Act passes, but because it has been a political football for 20 years, it’s a mess, and there’s not a good funding apparatus. It’s got a lot of problems in terms of how you actually measure and enforce toxic substances in food, and that difference haunts our regulatory system today.

Even today, under the Federal Meat Inspection Act, the USDA inspects meat-processing factories. It inspects about 10 to 20 percent of the food processing in the U.S., and it has almost the exact same budget that the FDA gets to inspect the other 80 percent of food. And a legacy of the difference between those two acts persists—one act was driven by a huge scandal that was incredibly powerful and had the backing of industry, and one was dragged over the line with industry hostile to it, working almost from the beginning to undo all of its better applications.

Bring us back to the present. How does the legacy of these food regulation laws continue to affect us today?

The Pure Food and Drug Act was eventually replaced by the 1938 Food, Drug, and Cosmetic Act, which created the modern FDA. There have been multiple [attempted] amendments since then to the FDA’s power, such as the Food Traceability Enhancement Act. But the fundamental weakness of the powers of the FDA to enforce safety measures in food, drugs and cosmetics—that still underlies our system in terms of both funding and in terms of some of the enforcement mechanisms we see today.

To be fair, the Federal Meat Inspection Act and the Pure Food and Drug Act of 1906 were paradigm-shifting laws. It was the first time in U.S. history that the government said, Yes, we’re in the business of protecting consumers. All of the consumer-protective things that followed—the Occupational Safety and Health Administration, the Environmental Protection Agency, the modern FDA—all of those agencies are built on those two laws. I mean, they made a huge and important difference.

So, despite industry pushback, all of these government regulations of our food supply have made Americans safer.

There’s no borax or salicylic acid added to our wine and beer. We’re not using arsenic as green food coloring. We’re not using red lead to make cheddar cheese look a little more orange.

If I could persuade people not to think of regulation as a pejorative term, my life’s work would be done.

Tanya Lewis is a senior editor covering health and medicine at Scientific American. She writes and edits stories for the website and print magazine on topics ranging from COVID to organ transplants. She also appears on Scientific American's podcast Science, Quickly and writes Scientific American's weekly Health & Biology newsletter. She has held a number of positions over her seven years at Scientific American, including health editor, assistant news editor and associate editor at Scientific American Mind. Previously, she has written for outlets that include Insider, Wired, Science News, and others. She has a degree in biomedical engineering from Brown University and one in science communication from the University of California, Santa Cruz. Follow her on Bluesky @tanyalewis.bsky.social

More by Tanya Lewis