Smoke dispersion from the Notre-Dame fire: INERIS confirms the map published by YOOTEST


The fire at Notre-Dame de Paris Cathedral dispersed a toxic cloud of lead-filled smoke over western Paris.

Due to the high toxicity of lead, it is essential to know precisely where the areas are in order to carry out surveillance and prevention actions of health risks to the population.

 What is the exact extent of the fallout from combustion residues (PAHs) and lead?

The National Institute for Industrial Environment and Risks (INERIS) is a public institution whose mission is to assess and prevent accidental or chronic risks to humans and the environment from industrial installations, chemical substances and underground operations.

At the request of the French authorities, INERIS scientific experts carried out a detailed study based on topographical and meteorological knowledge of the dispersion area to model the dispersion of the smoke from the fire. 

On November 26, 2019, INERIS published a report entitled "Modelling the dispersion of lead particles from the plume of the Notre Dame fire".

This 29-page document, which we invite you to consult, is available online and presents the area over which the smoke plume from the cathedral fire spread.

Here are some of the highlights that summarize the situation of the spread of this lead pollution quite well:

Impacts in the immediate vicinity of the source due to collapse phenomena are not modelled. This explains the absence of any representation of lead traces in the vicinity (in the order of the first kilometre) of Notre-Dame in the proposed illustrations, although the fallout is greater in this area.

What is the pollution in the immediate surroundings of the cathedral?

The nearby neighbourhoods have been heavily impacted by lead pollution.

These are the districts of the centre: I, II, III, IV and V, located immediately around the cathedral.

The relative stability of the wind direction during the fire explains the low dispersion of the plume, which extends along an axis linking Ile de la Cité to Mantes-la-Jolie. In the Paris conurbation, the plume impacts the northern tip of the 6th arrondissement, the 7th arrondissement, the North of the 15th arrondissement, and the 16th arrondissement. These districts constitute the area of greatest impact in any given scenario, with a decreasing gradient from the centre to the periphery of the city, it being accepted that the area around the cathedral subject to the local impacts of the disaster, not modelled, remained the area of maximum deposition.

How far has lead pollution spread?

On leaving Paris, the plume of the fire was affected by the effects of the relief associated with the Seine valley. The fallout extends as far as Mantes-la-Jolie, about fifty kilometres from the source.

Lead pollution in Notre-Dame Cathedral now affects the districts of central and western Paris and the municipalities of western Paris such as Neuilly-sur-Seine, Courbevoie, Nanterre, Rueil-Malmaison and this at least as far as Saint Germain en Laye.


Similarly, the possible transport of lead particles over very long distances (beyond 100 km) is possible, but it is reasonable to assume (as shown by this study) that most of these particles will have been deposited within the first 50 km.

Eight months after this disaster, it is a very substantiated report, written by specialists in the field, which formulates several hypotheses that lead to observations on the official extent of the pollution linked to the Notre-Dame fire and many elements of reflection such as the post-crisis health management of the exposure of the populations of the districts and cities affected by the fallout of lead residues.

A first map of smoke dispersion available from May 2019

In an article on lead pollution caused by the Notre-Dame de Paris fire published on May 10, 2019, the YOOTEST team published a map based on available weather data. 

The results of the INERIS study confirmed the smoke dispersion simulation presented by YOOTEST in May 2019. 

Lead is a very stable heavy metal in the environment and the pollution of Notre-Dame will be sustainable and will produce chronic exposure of populations with health risks for populations. This exposure, even at low doses, can have serious health consequences for children.

The authorities will give priority to establishments receiving the public (ERP), including nurseries, nursery and elementary schools, secondary schools, high schools and public buildings.

Control samples will be taken in accordance with the regulations using wipes that do not allow an accurate assessment of the health risks of lead pollution of the indoor environment. Indeed, this commonly used method does not allow the result to be compared with a health reference and therefore to qualify or quantify a risk to human health.

The public authorities will not seek lead in the private domain, so it is up to everyone to act to protect themselves and themselves from exposure to lead.

Dust analyses provide a reliable answer to lead pollution in homes, offices and shops. 
The individuals and professionals who used these analyses were able to become aware of the problem of lead pollution in their homes or business premises.

They were able to act accordingly and eliminate the lead deposits that polluted them.

Lead Pollution Test

Indoor air quality diagnosis to measure the pollution of the indoor environment by Lead. Test with laboratory analysis. Order your Test