Speaker 1: Welcome to brain Stuff, a production of iHeart Radio Pay
Speaker 1: brain Stuff Lauren Bogle bomb here. The fertilizer explosions that
Speaker 1: have killed hundreds and injured thousands of residents in unfortunate
Speaker 1: cities like Lebanon, Beirut, Breast, France, and Texas City in
Speaker 1: the US are notable not only for their terrible outcomes,
Speaker 1: but also because explosions from fertilizer manufacturing and storage are
Speaker 1: relatively rare occurrences. For a planet that uses about two
Speaker 1: hundred million tons of fertilizer a year, accidents are not ubiquitous. However,
Speaker 1: when ammonium nitrate, the compound linked to all of these disasters,
Speaker 1: does blow up, the effects can be devastating. On April six,
Speaker 1: ninety seven, about filled with twenty three hundred tons of
Speaker 1: ammonium nitrate and doctor near Texas City blew up as
Speaker 1: the result of a small fire on board. Nearly six
Speaker 1: hundred people were killed. That seven incident is ill one
Speaker 1: of the worst industrial accidents in US history. The tragedy
Speaker 1: in Lebanon in August has caused at least two d
Speaker 1: and twenty deaths and five thousand injuries, and has left
Speaker 1: and estimated three hundred thousand people without homes. It was
Speaker 1: caused by some three thousand tons of ammonium nitrate exploding.
Speaker 1: So how do fertilizers, which we often think of as
Speaker 1: natural compounds that are good for the earth, explode so violently.
Speaker 1: Let's begin with a little background on fertilizer itself. Plants
Speaker 1: need a few basic nutrients to grow, and most of
Speaker 1: them are found in the air and water and things
Speaker 1: like oxygen, carbon, and hydrogen. Of course, they also need
Speaker 1: some other elements that may or may not be rich
Speaker 1: in the soil that they're growing in. If a plant
Speaker 1: just needs a little bit of a nutrient, it's called
Speaker 1: a micronutrient, think a boron or chlorine. If a plant
Speaker 1: needs heaps of an ingredient, it's called a macronutrient, think nitrogen, phosphorus, potassium,
Speaker 1: and sulfur. And that's where fertilizer comes in. It packs
Speaker 1: the dirt with the secondary elements needed to make a
Speaker 1: plant flourish. Of course, many of us home gardeners would
Speaker 1: simply classify good old manure as fertilizer, and we wouldn't
Speaker 1: be wrong. According to the International Fertilizer Industry Association, any
Speaker 1: natural or manufactured material that contains at least five percent nitrogen, potassium,
Speaker 1: or phosphorus counts as a fertilizer. Of course, the fertilizing
Speaker 1: manufacturing industry produces synthetic or as they prefer to call them,
Speaker 1: mineral fertilizers. To manufacture mineral fertilizers, there are a few steps. First,
Speaker 1: you must collect the materials, which are in fact found
Speaker 1: in nature. Then you have to treat them to bolster
Speaker 1: the concentration or refine the products. After that you must
Speaker 1: convert them into a form that can be used by plants,
Speaker 1: and then you may want to combine those nutrients with others.
Speaker 1: One of the main components in manufactured fertilizer is ammonium nitrate.
Speaker 1: Like we said, nitrogen is one of those macronuts rents
Speaker 1: that plants love, so a lot of fertilizers are nitrogen based.
Speaker 1: Of course, we can't just bottle up some nitrogen and
Speaker 1: pour it on the old carrot patch. Atmospheric nitrogen has
Speaker 1: a really strong chemical bond that plants can't easily break,
Speaker 1: So fertilizer companies create nitrogen based substances that are much
Speaker 1: easier for plants to take. Apart ammonium nitrate is one
Speaker 1: such compound, and it's used for good reason. The ammonium
Speaker 1: part sticks around longer without evaporating, so it's great for
Speaker 1: hot summer fields, and the nitrate is easily used by
Speaker 1: plants even more compelling in the agricultural industry. It's inexpensive
Speaker 1: to manufacture. You can bine ammonia and nitric acid and
Speaker 1: you're done. But what makes ammonium nitrate capable of such
Speaker 1: lethal explosions? Perhaps, surprisingly not much. Ammonium nitrate is a
Speaker 1: relatively stable compound, according to the US Environmental Protection Agency.
Speaker 1: In other words, when it's just sitting quietly somewhere, ammonium
Speaker 1: n trait isn't that big of a problem because it
Speaker 1: needs a relatively high activation energy, that is, the energy
Speaker 1: needed to cause a chemical reaction in order to explode. However,
Speaker 1: if an accident where some sort of detonation, a spark,
Speaker 1: or some other kind of energy occurs, you better believe
Speaker 1: that ammonium nitrate is deadly. The compound essentially makes its
Speaker 1: own fuel from the ammonium and oxidizer the nitrate, so
Speaker 1: its reaction is violent and long lasting. So it makes
Speaker 1: sense that a fire seems to be the cause and
Speaker 1: not the outcome of what happened in all of these
Speaker 1: tragic explosions. It's worth repeating that although ammonium nitrate and
Speaker 1: other fertilizer explosions are terrible, they're rare, but would be
Speaker 1: remiss to not mention that fertilizer can also make a
Speaker 1: deadly intentional weapon. Timothy McVeigh, for one, used a fertilizer
Speaker 1: bomb in Oklahoma City bombing m Today's episode was written
Speaker 1: by Kate Kirshner and produced by Tyler Clang. For more
Speaker 1: on this and lots of other topics, visit how stuff
Speaker 1: works dot com. Brain Stuff is production of I Heart
Speaker 1: Radio or more podcasts. For my heart Radio, visit the
Speaker 1: I Heart Radio app, Apple Podcasts, or wherever you listen
Speaker 1: to your favorite shows.