In 1926, the federal government increased the amount of methanol, a poisonous alcohol-based substance, required in industrial alcohols, which people at the time used to make bootleg liquor. Faced with the ongoing failure of Prohibition, the increase was intended to discourage people from drinking.

"It gives a greater warning to the drinker that he is getting hold of something that he should leave alone," a government chemist told the New York Times at the time.

But people didn't stop drinking. Thirsty for any booze they could get, many Americans risked drinking the super-poisoned alcohol — and thousands died as a result.

Deborah Blum, a Pulitzer Prize-winning science journalist and author of The Poisoner's Handbook: Murder and the Birth of Forensic Medicine in Jazz Age New York, previously wrote about the topic for Slate. I spoke with Blum by phone recently about this wrong-headed government scheme and its implications.

German Lopez: Tell me about the time the federal government purposely poisoned alcohol.

Deborah Blum: Even before Prohibition, the government required industrial alcohol manufacturers to add contaminates to their product to separate it from drinking alcohol. So the government already had an apparatus in place to require these manufacturers to add different things into the alcohol to taint it so it's non-drinkable.

Come the middle of the 1920s, people are still drinking alcohol, and alcoholism rates are rising. As part of that, there's increasing evidence of methanol poisoning across the country. So the government comes back and says, "Well, okay. We have this sort of scatter-shot of alcohol poisoning across the country. But the bootleggers are taking industrial alcohol and cleaning it up, and that's not putting people off from drinking. So what if we made that industrial alcohol really poisonous? We would make it so poisonous that it would be so scary that people wouldn't drink it."

The government then passed regulations in 1926 that required the industrial manufacturers to add a lot of poisonous things into their alcohol knowing that this stuff was going to get stolen by bootleggers and people were going to drink it. The moral crusade idea was that people won't drink anything that might kill them, which was obviously ridiculous since people were already drinking unsafe alcohol at the time.

GL: What did they put in the industrial alcohol?

DB: They put all kinds of poisonous stuff into the alcohol. There was benzine, there was mercury, there was this list of formulas that's heart-stopping horrible. But in particular they put more wood alcohol, or methanol, because their own tests showed bootleggers couldn't get it out — it's too closely bonded to the drinking alcohol.

It was like a chemists' war at this point. Bootlegger chemists trying to take things out, and government chemists trying to find a way to keep them in. But the bootlegger chemists had not been able to find a good way to get methanol out. People knew this was going to kill people. They were warning the government in advance. Charles Norris, who was the chief medical officer in New York City, and Alexander Gettler, who was the chief toxicologist in the city, told the government not to do this.

The government did it, anyway. People started dying right away. There was this wash of super-poisoned alcohol turning up everywhere, because it was the only stuff someone could get. This was the alcohol of the country.

GL: How many people died as a result of this?

DB: The estimates I saw were about 10,000. Experts could say at the time that those deaths were over and above the other alcohol-related deaths. These numbers notched up after the more poisoned alcohol went into the market. But it's not a clean calculation.

When I first saw a newspaper article about this, I thought it couldn't be right. The government wouldn't have done that, and I would have heard about it if it happened. I ended up hunting it down through all kinds of newspapers and magazines of the time.

That was when I realized that this was widely known when they instituted this program. Charles Norris wrote this fantastic indictment called "Our Essay in Extermination" about the government poisoning American citizens through Prohibition. So there was a real scandal nature to it when it happened.

GL: What was the reaction like at the time?

DB: It's really an interesting political period. Political coverage at the time put people into two shorthands: the dries and the wets. The dries were all the people in political power who believed that we should be a dry nation, and the wets were the opposite.

At this moment in the mid-1920s, the dries are definitely in power. They're running the Treasury Department, which is the department that primarily enforces the liquor laws. The president at the time, Calvin Coolidge, is a dry politician; Herbert Hoover, who also came in later, was a dry politician.

They announce the plan as a big warning message from the government: "Quit drinking, because we're going to make this a lot more poisonous." They even had moments when they would call in reporters to make sure everyone knew.

Public health officials, like Norris, pointed out that people were already dying from all kinds of poisoned alcohol because they couldn't get access to legal, safe alcohol. They knew more people would die from the government's plan.

GL: So what was the effect of this policy? It seems to me like it would just hurt poor people, because wealthier people could afford the best liquor at the time.

DB: Right. There was still very expensive liquor that someone could get if they were willing to pay a lot for it. It was smuggled in, primarily from Canada or the Caribbean. There were also companies that would take people on cruises down to the Caribbean. If someone had enough money, people could pay to get the good stuff smuggled in from Europe. And if someone had the money, they could make a good backyard distillery.

But if someone went to a speakeasy, he wouldn't know where the speakeasy got its liquor. That led to deaths, but they didn't really happen among the wealthy.

Now, the government's regulations weren't the only source of poisoned liquor. Some of the bootleggers also set off all sorts of different poisoning episodes.

There's a famous example called Ginger Jake. As bootleggers tried to find more liquor substitutes, they made different formulas. In the South in particular there was this Jamaican ginger, which was basically ginger-flavored alcohol. When that got stopped by Prohibition, there were a lot of people who wanted to find a replacement. They came up with a formula that gave a buzz with no alcohol, but it had some chemical compounds that are neurotoxic. These compounds actually attack the same parts of the neural system that are damaged by amyotrophic lateral sclerosis. People started popping up with semi-paralytic symptoms, and at first people thought it was polio.

Again, this affected poor people. This was a poor man's drink.

GL: Another thing that's interesting about this story is that the government did something similar with marijuana in the 1970s.

DB: Right. The Paraquat spraying. The government was trying to get rid of marijuana plants in Mexico, and they sprayed plants with this herbicide that they thought would kill them. But it didn't kill them all. What it did was load the plants with poison.

The government basically said, "Oh well." This was basically the government response to the poisoning in the 1920s. "Oh well, you're an evil lawbreaker. If you get poisoned, that's your problem."

GL: What do you think this all says about prohibition and the war on drugs?

DB: It shows that moral crusades are really dangerous. People really do believe that they're on the side of the angels, and that the ends justify the means.

But what did Prohibition accomplish? Nothing good, as far as we can tell. Again, the prohibition of marijuana encourages the same kind of illegal industry that Prohibition did in the 1920s. My feeling is that it's really hard to legislate human behavior.

I don't want to assign evil to this entirely. People genuinely believed that if they put the right moral code into legislation, they could change society for the better.

But there is a sort of classist, ethnic component to this. Certainly, people have made the case that early on the primary users of marijuana in the United States were African American. Those early drug laws and the underpinnings of our anti-marijuana crusade were rooted in that.

If you look at Prohibition, the people who were most hurt were also poor city dwellers. Out in the mountains of Georgia, people just brewed their own distillery. The real impact of Prohibition and poisoned alcohol was on poorer people in the cities.

GL: What is the takeaway from this moment in history?

DB: Prohibition was a failed experiment. The lesson was we really can't do that. When we did it, we had all sorts of unintended consequences.

We need to know that our government is capable of these things. Let's not be naive about it. If you can go back 100 years and see the government seems okay with sacrificing American citizens to enforce its laws, that is worth remembering.

This interview has been edited for length and clarity.