More than two weeks have passed since an explosion of 2,750 tonnes of ammonium nitrate killed more than 160 people in Beirut. The chemical had been stored in a warehouse near the city’s cargo port for almost six years, after being seized from a ship that became stranded there because of technical problems.
An investigation into exactly what triggered the blast on 4 August is under way, but according to Najat Saliba, an analytical chemist at the American University of Beirut, it is being conducted by the Lebanese army, and it is unclear whether the results will be made public.
Nature spoke to Saliba about the aftermath of the explosion, the situation on the ground, and what the country’s researchers can do to help.
What information do we have so far about why the explosion happened?
We know that the explosion involved a large quantity of ammonium nitrate. Some assumed that the reddish plumes of smoke suggested that the explosion is not related to ammonium nitrate. But if you look at the Texas City explosion of 1947 and other ammonium-nitrate explosions, all of them exhibited the same coloured gas.
As a chemistry researcher, I also know that ammonium nitrate can usually be stored for a long time, and that it cannot explode on its own — there needs to be a detonation.
What questions should the investigators be asking?
I would want to know about the conditions in which the ammonium nitrate was stored. Was it stored in a proper container that is blast-proof? Was there fuel stored next to this container that represented a major hazard? And what compliance mechanisms did the authorities put in place — what kinds of checks every year or every month — to make sure that the site was safe?
There will have been compliance standards that the government is obliged to follow, regarding the chemical, how it is stored, other dangerous hazards nearby, and the risks to populations.
What is the role of analytical scientists such as yourself in investigating the blast?
Our role should be to collect samples from the site and understand their chemical composition, so that we can establish what detonated the ammonium nitrate.
We could also perform chemical analysis on air, soil and water, dividing the site into circles, separated by 3 to 4 metres. Researchers would start in the area located close to the explosion site, and then move wider.
But this process has still not begun; the site is completely blocked by the army. They are doing their own investigation into the explosion, and are not working with academic researchers.
Is that something that could create problems?
In terms of science, it doesn’t matter who is doing the investigation, as long as they have the equipment. Whether samples are being collected by local researchers or international teams, they will do the same job. But the samples need to be collected properly and sent to a certified laboratory.
At the moment we don’t know what capacity our army has, whether they have the required testing and analytical facilities, what samples they are collecting, or where they are sending the samples.
The analysis is what really matters. Whether there will be enough transparency about the results, that’s a different question. It is unclear if and when the data will be shared with the public.
Is there work that researchers could do once the site is open?
It is going to be too late, but if I were to search for something, I would search for heavy metals and nitrogen compounds, and try to understand what detonated the ammonium-nitrate container.
That would be the job of a forensic scientist, however. The job of chemistry and toxicology specialists like me would be to make sure that people are safe from any contamination.
It would’ve been ideal if we could have taken samples from the air, but unfortunately we didn’t have our monitoring stations installed, and as far as I know, no one took air samples just after the explosion.
How is air quality in the area at the moment?
There probably isn’t much air pollution from the blast itself, but the air close to the ground is polluted. There is debris everywhere, there is powdered glass everywhere. There was not a single piece of glass in the neighborhood that could withstand the blast.
Right now, people are trying to collect the glass, but this is not enough. You can’t imagine the amount of glass that has been broken and has to be cleaned up.
The government does have some plans for how to manage the glass and the construction debris, and how to separate that from the solid waste and dust from the blast. All of this is creating a mix that worries me.
What safety measures should Beirut residents consider?
If they are living in a place facing the explosion site, and if there is a lot of dust, it is important to put on either a mask or a face shield, if possible. That simple measure will protect a lot of lives.
How could the current situation be resolved?
You cannot imagine the atrocity and the enormous disaster that we are living in, it’s beyond belief. People don’t have doors and windows, they don’t have a safe shelter.
We need to have a solid waste-management plan, coupled with an aftershock waste plan. All arms of the government need to be on the ground, plus the army, and NGOs, to help the people clean up the debris and get their shelters and homes back.
This interview has been edited for length and clarity.