The Seveso classified industrial site contained substances that were dangerous for humans and the environment. During the fire, the fumes from the Lubrizol plant contained, in addition to combustion residues, many toxic chemicals.
Soot and oil particles have settled on plants, soil, soil, roads, buildings and their roofs.
Not only the city of Rouen but also the places where smoke passes through must be cleaned up because the health risks and the effects of chronic exposure to this pollution are significant in the medium and long term.Knowing that this pollution has been followed to the Netherlands there is a very important area towards the North-East from Rouen that is impacted.
How long will the pollution produced by the fire last ?
Although it is very difficult to decide how long it will take for pollution to decrease and no longer pose a chronic risk to the population, knowing the half-life periods in the environment makes it possible to estimate the length of time pollution will be present.
The half-life of a substance is the time required for the concentration to decrease by half
For most of the pollutants deposited with smoke deposition, environmental data on persistence in the environment are not known. It is recognized that it takes 10 half-life periods to eliminate 99% of pollution.
Without reference data to evaluate this duration, it is necessary to carry out spot measurements over a long period to evaluate the decrease in pollution over time.
It is therefore important to take samples and perform analyses.
Is looking for VOCs relevant to identify the Lubrizol pollution?
Volatile Organic Compounds (VOCs) such as benzene, toluene, ethylbenzene, xylene and naphthalene are formed during the combustion of materials.
Although they are of great health concern (benzene and naphthalene in particular), as they are volatile, they do not remain in the environment for long.
Therefore, considering VOCs for long-term pollution assessment is not relevant.
The PAHs, markers of the Rouen industrial fire?
Polycyclic Aromatic Hydrocarbons or PAHs are assemblies of several aromatic rings (benzene). Few volatile, very stable and persistent in the environment, they are the main markers of fires.
The health and environmental effects of PAHs are now well known and it is recommended to limit exposure to these substances dangerous to humans as much as possible.
Therefore, after a fire, it is advisable to measure these combustion residues in order to measure the level of pollution, assess health risks and, if necessary, take the necessary measures to eliminate the pollution.
In most dwellings, they are found in small quantities (concentration less than 200 ng/g of dust).
The warehouse that was burned contained multiple chemicals: mineral oils (heavy hydrocarbons) and multiple additives. These elements are specific chemical markers of pollution induced by the lubriczol fire.
They are therefore identifiable by a targeted analysis.
All mixed chemicals can react with each other and form new molecules that will need to be identified by laboratory analysis.
As a result, this industrial accident caused a dispersion of unknown products whose effects on human health for acute and chronic exposures are unknown.