Beirut Explosion: The Chemistry Behind the Tragedy

by Sophia Freires

Hiraya Zine
5 min readNov 12, 2021


Trigger Warning: This article may contain distressing depictions of explosions and death.

Note: This article was previously published in Hiraya Zine Volume 1, Issue 2: Science for Society last September 2020.

Smoke rising at Beirut, Lebanon after the explosion. Photo by Getty Images via The New York Times.

We have seen this year’s share of mishaps, from facing a pandemic to experiencing natural disasters. The misfortunes the world experienced were sudden and widespread, leaving many unhinged from the realities they used to live in. One of these devastations occurred in Beirut, the capital of Lebanon. Last August 4, the Lebanese people experienced a deadly explosion, which upended their lives and brought tragedies they did not deserve.

The Beirut explosion claimed the lives of at least 190 people, injured around 6000 people, and left the nation in bewildered shock and grief. To make matters worse, about 15,000 people were left homeless and citizens looked on helplessly at the destruction in their city and loss of livelihoods. The explosion even made its way to the Richter scale, responsible for measuring the strength of an earthquake, and was registered under magnitude 3.3.

It is only natural for people to seek answers as to what could cause this horrifying event. As the world is yet to uncover the whole picture, fragments of it are already falling in place. Two words spell out the cause authorities are pointing their fingers at: ammonium nitrate.

The chemistry

In your mother’s garden, you may recognize ammonium nitrate as a key component in her fertilizer. In the deep recesses of the caves, mining companies utilize ammonium nitrate for blowing up sections. In the dark passages of history, it has been one of the main components of bombs that lead to a series of catastrophes. Now, approximately 2,750 metric tons of the substance is eyed as the root cause of the Beirut explosion. So, what is in ammonium nitrate that can make it explosive?

Ammonium nitrate. Photos by Z. Tammana on (left) and Sky News.

Ammonium nitrate (NH₄NO₃) is a chemical compound, and is a white solid, in a form resembling powdered- sized bits. When left by itself, the compound in question is quite harmless, as it does not explode on its own and is safe to use at room temperature. Now, when outside factors enter the picture, a different version of the story can be weaved.

Let us tackle these factors one by one to avoid brewing confusion. First, rapid heat can force the compound to undergo a process or reaction, where it turns into nitrogen, oxygen, and water vapor. While these products are harmless, the reaction dispenses energy into its surroundings and can have an impact. Now, when we weigh in the quantity of ammonium nitrate, a heavy amount can define that impact as an explosion. The more tons it weigh, the more dangerous an explosion will be.

Another influence of a possible explosion is the environment. Is the compound situated in an open field? Is it locked up in an enclosed space? The setting greatly affects the possibility of an explosion. If left burning on an open area, pressure can travel in all directions and escape. If the ammonium nitrate is stored, there would be a build- up of trapped pressure and leads to an increase in heat, encouraging a powerful explosion.

Ammonium nitrate (NH₄NO₃) can serve as an oxidizing agent. Illustration by Byjus.

Let’s delve inside the inner workings of the compound and dissect a property that can make it deadly. Ammonium nitrate is deemed as an oxidizer, whereas it donates oxygen to its surroundings. It is a fact that flammable substances require oxygen to keep on burning. Say that a flammable substance, such as gasoline, suddenly sets off a fire and the ammonium nitrate feeds the hungry substance through its donation of oxygen. Their relationship is a classic example of an ill-fated one you see on television as the gasoline’s flames can possibly trigger the compound, causing it to detonate.

The scene

Now that you are aware of these factors, it is time to connect the dots on the Beirut explosion. The 2,750 tons responsible for the destruction was stored in a closed warehouse along with fireworks, hydrochloric acid, kerosene, oil, and wooden spools that can act as a fuse. These are ingredients eager to gobble up the oxygen ammonium nitrate can give.

On the evening of August 4th, a fire was implied to have broken out inside the warehouse as smoke was seen rushing out and fireworks were exploding. Experts have commented that the explosion of fireworks could have detonated the ammonium nitrate. More smoke, carrying unexploded ammonium nitrate, rises after the miniature fireworks display. We must take note that in nature, it is common to see the compound not fully converting form or being used up. While these events already screamed danger, the following incident directly affected parts of the city.

Characterized by a sudden flash, the explosion occurred shortly after, consuming most of the ammonium nitrate. What led half the city to ruins though was the resulting shockwave, seen rippling through the city. Traveling faster than the speed of sound and bringing along high air pressure, the shockwave swept the buildings nearby, blasted through windows, engulfed homes, sent threatening debris flying, tossed people against their will, and after then, left the city ringing with distress.

An assessment being conducted after the Beirut Explosion. Photo by Human Rights Watch.

Right now, we see the aftermath being played out through our eyes. Families and friends grieve over their loved ones as organizations and the people work hand in hand to provide the support victims need. Citizens attempt to rebuild part of the heritage and culture the tragedy had stolen from them as individuals struggle to pick up the pieces and continue on living.

To add more to this whole devastating mix, an economic crisis and political conflicts endanger the people’s welfare and Lebanon’s development. It doesn’t also help that the invisible enemy, the pandemic, still looms over their heads.

Ways to help

There is a way for us to give Lebanon a teeny-tiny push even if we are miles away. This website embeds several links that can offer us the chance to give the aid its citizens would appreciate. A percentage from your monthly allowance can encourage someone to push through. While it is essential to seek the full picture of the explosion, rebuilding the future and moving towards better, sunny days is of greater importance. ✴

#ARCHIVES: This article was previously published in Hiraya Zine Volume 1, Issue 2: Science for Society last September 2020. Download the zine for free here.



Hiraya Zine

Flagship project of SciCreate, bridging the gap between researchers and the youth through the use of art, writing, and the humanities in quarterly zine issues.