The recent disaster of April 15, 2019, which saw the roof of Notre-Dame almost completely destroyed, caused significant air pollution not only with toxic combustion residues but also with the lead contained in the burnt-out parts of the cathedral.
This outdoor air pollution has led to high indoor environmental pollution of the surrounding buildings (homes and offices) by fine particles of soot loaded with polycyclic aromatic hydrocarbons (PAHs) but also lead.
What is the magnitude of this lead pollution?
According to many newspapers, the spire of Notre-Dame de Paris alone contained more than 250 tonnes of lead.
The newspaper Libération reports that "some 400 tonnes of lead contained in the roof and arrow of the cathedral, as in the paintings, have vanished into yellow volutes loaded with toxic particles. »
Another publication, l'Express, goes further and gives the figure of 460 tons by adding the arrow to the 1326 lead tiles on the roof.
The combustion in the fire released an extremely large amount of lead into the atmosphere. The toxic lead-filled fumes produced contaminated the environment for several hundred yards in the vicinity of the incident.
For comparison, in the indoor environment, lead contamination is measured in µg (microgram) and one billion (1,000,000,000,000) µg is 1 kg.
The residents of Notre-Dame de Paris have been invited by the authorities (Préfecture de Police de Paris) to clean their homes to limit the presence of these toxic dusts in their homes. However, only the largest dust particles are removed by conventional cleaning, but most of the pollution of the indoor environment remains invisible and insidiously threatens the health of the occupants.
What are the health effects of lead?
Lead is a natural element of the heavy metal family, used since ancient times. It has no function in the functioning of living organisms. The harmful effects of lead are well known and everyone has already heard about lead poisoning which still affects several thousand children under the age of 6 in France today according to the Institut de Veille Sanitaire (InVS).
It is scientifically proven that lead is a toxic substance that acts at any dose, no matter how low it is.
Lead easily enters the body through ingestion or inhalation and accumulates in the body, especially in the bones. Lead poisoning mainly affects the nervous system, bone marrow and kidneys. Lead easily passes through the placental barrier and contaminates breast milk, posing a significant risk of exposure to fetuses and infants.
The Lead Habitat study published in 2012 made it possible to assess the usual contamination of French housing with this metallic trace element. Wipes are passed over a defined area of the floor. The dust collected on the wipes was analyzed in the laboratory for lead measurement.
The results of this study show that one in two children's rooms contains more than 6 µg/m2 of lead compared to more than 8 µg/m2 in the rest of the dwelling. The 5% of the most contaminated children's rooms contained more than 42.3 µg/m2 of lead, a lower value than the rest of the dwelling with 62.6 µg/m2. In conclusion, a large part of the dwellings contain lead residues in the dust, children's rooms are significantly less contaminated than other rooms in the house. In addition, the older the dwelling, the higher the lead content, with a marked decrease for buildings built after 1993.
How do we know if we've been contaminated by these lead fumes?
It is therefore essential for residents to measure the lead content in the indoor environment of apartments or offices near Notre-Dame de Paris with laboratory analysis to look for lead and combustion residues. This measure makes it possible to assess and identify a situation that poses a risk to the health of the occupants.
Picture : © Charles Edward Miller