The Men Who Volunteered to Be Poisoned by the Government

Harvey Washington Wiley, the brusque and determined leader of the Department of Agriculture's Bureau of Chemistry in Washington, D.C., had good news and bad news for the 12 young men who had answered his call for volunteers. First, Wiley promised them three ample, freshly prepared meals every day for at least six months. Since the majority of the men were Department clerks living on modest wages, this was a tempting offer. The volunteers would also be under exceptional medical care, with weekly physicals and daily recordings of their weight, temperature, and pulse rate.

This was, Wiley explained, because he’d be slowly poisoning them.

Wiley’s staff would put borax in their butter, milk, or coffee. Formaldehyde would lurk in their meats, copper sulfate and saltpeter in their fruit pies. Wiley would begin at low doses and then ratchet up the amount until one or more of the men complained of debilitating symptoms, like vomiting or dizziness. Those people would then be excused from the program until they felt well enough to resume. In the event a subject died or became seriously ill, he would waive the right to pursue legal remedy against the government.

The year was 1902. With funding and consent from Congress, Wiley was about to embark on an experiment he dubbed the “hygienic table trials,” but it was the Washington news media that came up with the nickname that would stick: They called his volunteers "the Poison Squad."

The Poison Squad dining area. Image credit: FDA History Office [PDF] // Public Domain

At the turn of the last century, food manufacturers and distributors were untouched by government oversight. There were no federal requirements for labeling, which meant ingredients didn't need to be listed, and there were no explicit consequences for tampering or adulterating consumer goods. Parents would unwittingly give their babies cough syrup containing morphine to calm them down. Olive oil might actually be cottonseed oil, which was cheaper for makers to source; glucose could be passed off as honey.

A former professor of chemistry at Purdue University, Wiley was aghast at the freewheeling nature of the food industry. He was especially concerned with the use of preservatives, intended to ward off spoilage but poorly understood when consumed in consistent amounts over time. Taking a post as chief chemist at the Department of Agriculture in 1883, Wiley repeatedly petitioned for money and resources to quantify how these substances impacted the human body. Time and again, food lobbyists would thwart his attempts.

In 1902, Congress finally agreed to Wiley’s persistent requests, offering him $5000 to subsidize an experiment on the effects of food additives with a group of men who would spend at least six months, and eventually up to a year, in his service. In the basement of the Bureau’s Washington office, Wiley set up a kitchen, dining room, and lab; he installed a chef, known only as “Perry,” to prepare a variety of welcoming dishes for his volunteers. Roast chicken and braised beef would be served alongside borax and formaldehyde.

Although the ethics of the study could be debated both then and now, Wiley disclosed his intentions to the 12 men who signed up for the program. Mostly young, they were selected for having durable constitutions that might more easily withstand the accumulation of foreign chemicals. Wiley believed if the dosages bothered them, then children and older members of the public were in even more danger.

In exchange for free food and the sense of contributing to the betterment of society, the volunteers agreed to eat their three daily meals only in the test kitchen. No snacking between meals would be permitted, and only water could be ingested away from the table. Their weight, pulse, and temperature would be recorded before sitting down. Wiley also had each man carry a satchel with them at all times to collect urine and feces for laboratory analysis. “Every particle of their secreta,” Wiley said, was necessary to the trial.

The first treat was borax, a ground mineral commonly used to preserve meats and other perishables. Wiley allowed the men a period of 10 to 20 days of eating normally to establish baseline readings of their health and symptoms before Chef Perry began adding a half-gram of the powder to their butter. Although the men knew borax would be served, they didn’t know how—yet most all of them quickly began avoiding the butter out of instinct once they had gotten a taste of it.

Wiley next tried slipping it into their milk, but the same thing happened: They stopped drinking the milk. Having failed to account for the body’s natural resistance to being contaminated with the metallic-tasting substance, he began offering borax-filled capsules with each meal. The men dutifully swallowed them as a kind of dessert following the main course.

Wiley’s squad tolerated the borax—7.5 grains daily—for several weeks. But after a few months, headaches, stomach aches, and depression began to materialize. At six months, they threatened to go on strike unless the slow drip of poison stopped. The summer months seemed to exacerbate their ailments.

By then, Wiley had gotten enough data on borax. He moved on to salicylic acid, sulfuric acid, sodium benzoate, and other additives, administering each one at a time, all across the menu, to assess the response. Sometimes, the progression was so uneventful that the men took it upon themselves to liven up the proceedings. One laced a colleague’s drink with quinine, which can cause headaches and profuse sweating. Not long after, the man went out on a date; he later recounted that when he began to feel the symptoms of the quinine, he "went home prepared to die in the interest of science." (He was fine.)

Other times, the experiments were as dangerous as advertised. Owing to excruciating symptoms, the trial with formaldehyde was terminated early.

A sign posted in the Poison Squad's dining room. Image credit: FDA via Flickr // U.S. Government Works

Rotating members of the Poison Squad convened for roughly five years between 1902 and 1907. All along, lobbyists fought to suppress Wiley’s findings. His 477-page report on the effects of borax was well-received, but supervisors—and even the Secretary of Agriculture—tried to stifle his review of benzoic acid, a widely used preservative, due to its damaging findings and subsequent pestering by food lobbyists. The report was leaked only when the Secretary was away on vacation and a staffer misunderstood his instructions, ordering it printed by mistake.

In 1906, Congress passed both the Pure Food and Drug Act and the Meat Inspection Act, both designed to restrict the kinds of preservatives and additives used by food companies. The former was known as the “Wiley Act,” because Wiley had been the one to demonstrate the need for its inception. They were the first federal laws to regulate food. By the 1930s, Wiley's Bureau of Chemistry had morphed into the Food and Drug Administration—and almost all of the additives Wiley trialed had been excised from the commercial food industry.

Wiley himself remained with the Department of Agriculture until 1912, when he began a 19-year position as a consumer advocate for Good Housekeeping magazine. The public, which had come to know Wiley through the extensive media coverage of the Poison Squad, looked upon him as a reliable source for information.

In 1927, Wiley used his position to notify readers of a toxic substance that was widespread, commonly absorbed, and had underestimated potential to cause cancer. The American public, he warned, should be very wary of tobacco. While Good Housekeeping stopped accepting cigarette ads in 1952, the Surgeon General didn't issue a formal warning until 1964.

Meanwhile, the dozens of men who consented to the regulated poisonings were said to have suffered no lasting effects, save perhaps for one. In 1906, the family of poison squad member Robert Vance Freeman used the press to blame the man’s tuberculosis and subsequent death on the borax he was made to consume. Although Wiley had discharged Freeman in 1903 because his symptoms had rendered him “disabled,” he dismissed any idea the borax was at fault in his death. No charges or lawsuit were ever filed.

Although an experiment involving purposeful and deliberate doses of poison could never be described as "safe," Freeman's fate was an anomaly. Wiley made certain to limit a volunteer's service to one 12-month term, with the chemist correctly observing that “one year of this kind of life is as much as a young man wants.”

Additional Sources: "The Poison Squad and the Advent of Food and Drug Regulation" [PDF]

Why Does Humidity Make Us Feel Hotter?

Tomwang112/iStock via Getty Images
Tomwang112/iStock via Getty Images

With temperatures spiking around the country, we thought it might be a good time to answer some questions about the heat index—and why humidity makes us feel hotter.

Why does humidity make us feel hotter?

To answer that question, we need to talk about getting sweaty.

As you probably remember from your high school biology class, one of the ways our bodies cool themselves is by sweating. The sweat then evaporates from our skin, and it carries heat away from the body as it leaves.

Humidity throws a wrench in that system of evaporative cooling, though. As relative humidity increases, the evaporation of sweat from our skin slows down. Instead, the sweat just drips off of us, which leaves us with all of the stinkiness and none of the cooling effect. Thus, when the humidity spikes, our bodies effectively lose a key tool that could normally be used to cool us down.

What's relative about relative humidity?

We all know that humidity refers to the amount of water contained in the air. However, as the air’s temperature changes, so does the amount of water the air can hold. (Air can hold more water vapor as the temperature heats up.) Relative humidity compares the actual humidity to the maximum amount of water vapor the air can hold at any given temperature.

Whose idea was the heat index?

While the notion of humidity making days feel warmer is painfully apparent to anyone who has ever been outside on a soupy day, our current system owes a big debt to Robert G. Steadman, an academic textile researcher. In a 1979 research paper called, “An Assessment of Sultriness, Parts I and II,” Steadman laid out the basic factors that would affect how hot a person felt under a given set of conditions, and meteorologists soon used his work to derive a simplified formula for calculating heat index.

The formula is long and cumbersome, but luckily it can be transformed into easy-to-read charts. Today your local meteorologist just needs to know the air temperature and the relative humidity, and the chart will tell him or her the rest.

Is the heat index calculation the same for everyone?

Not quite, but it’s close. Steadman’s original research was founded on the idea of a “typical” person who was outdoors under a very precise set of conditions. Specifically, Steadman’s everyman was 5’7” tall, weighed 147 pounds, wore long pants and a short-sleeved shirt, and was walking at just over three miles per hour into a slight breeze in the shade. Any deviations from these conditions will affect how the heat/humidity combo feels to a certain person.

What difference does being in the shade make?

Quite a big one. All of the National Weather Service’s charts for calculating the heat index make the reasonable assumption that folks will look for shade when it’s oppressively hot and muggy out. Direct sunlight can add up to 15 degrees to the calculated heat index.

How does wind affect how dangerous the heat is?

Normally, when we think of wind on a hot day, we think of a nice, cooling breeze. That’s the normal state of affairs, but when the weather is really, really hot—think high-90s hot—a dry wind actually heats us up. When it’s that hot out, wind actually draws sweat away from our bodies before it can evaporate to help cool us down. Thanks to this effect, what might have been a cool breeze acts more like a convection oven.

When should I start worrying about high heat index readings?

The National Weather Service has a handy four-tiered system to tell you how dire the heat situation is. At the most severe level, when the heat index is over 130, that's classified as "Extreme Danger" and the risk of heat stroke is highly likely with continued exposure. Things get less scary as you move down the ladder, but even on "Danger" days, when the heat index ranges from 105 to 130, you probably don’t want to be outside. According to the service, that’s when prolonged exposure and/or physical activity make sunstroke, heat cramps, and heat exhaustion likely, while heat stroke is possible.

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This article has been updated for 2019.

Chimpanzees Bond by Watching Movies Together, Too

Windzepher/iStock via Getty Images
Windzepher/iStock via Getty Images

Scientists at the Wolfgang Kohler Primate Research Center in Germany recently discovered that, like humans, chimpanzees bond when they watch movies together, the BBC reports.

In the study, published in Proceedings of the Royal Society B, researchers stationed pairs of chimpanzees in front of screens that showed a video of a family of chimps playing with a young chimp. They found that afterward, the chimps would spend more time grooming and interacting with each other—or simply being in the same part of the room—than they would without having watched the video.

They gave the chimps fruit juice to keep them calm and occupied while they viewed the video, and they chose a subject that chimps have previously proven to be most interested in: other chimps. They also used eye trackers to ensure the chimps were actually watching the video. If you’ve ever watched a movie with friends, you might notice similarities between the chimps’ experience and your own. Drinks (and snacks) also keep us calm and occupied while we watch, and we like to watch movies about other humans. Since this study only showed that chimps bond over programs about their own species, we don’t know if it would work the same way if they watched something completely unrelated to them, like humans do—say, The Lion King.

Bonding through shared experiences was thought to be one of the traits that make us uniquely human, and some researchers have argued that other species don’t have the psychological mechanisms to realize that they’re even sharing an experience with another. This study suggests that social activities for apes don’t just serve utilitarian purposes like traveling together for safety, and that they’re capable of a more human-like social closeness.

The part that is uniquely human about this study is the fact that they were studying the effect of a screen, as opposed to something less man-made. The chimps in question have participated in other studies, so they may be more accustomed to that technology than wild apes. But the study demonstrates that we’re not the only species capable of social interaction for the sake of social interaction.

[h/t BBC]