In April 2019, flames engulfed 460 tons of lead when Notre-Dame’s roof and spire burned, scattering dangerous dust onto the streets and parks of Paris. As the fire raged and the roof collapsed, some of the lead covering the roof and spine was dispersed as dust. Levels of lead dust deposited near the cathedral were up to 1300 times higher than French safety guidelines. The highest peak measured was approximately 120,774 microgram of lead per square foot. The lead spread across central Paris, tests indicate, settling in schools, park and other public spaces. All places were lead was found above the guideline level of 93 micrograms per square foot cited by some French officials.

More than 6000 children younger than age 6 live within a half mile of those locations according to the Times analysis. Lead exposes poses the greatest risk to children especially under the age of 6, as well pregnant women and nursing mothers, who can pass lead on to their children. If ingested, lead interferes with the normal development of the nervous system and can leave young children with permeant cognitive damage, producing issues that range from the loose a few I.Q. points to difficulties with reading and a tendency toward agressive behaviour. Lead symptoms in children are related to the lead encephalopathy causing additional symptoms such as lethargy, vomiting, loss of appetite and dizziness, progressing to obvious ataxia and reduced level of consciousness which may lead in fatal cases to coma and death.

According the Health Ministry of Health the lead levels above 70 micrograms per square meter or 6,5 micrograms per square foot represents a risk of lead contamination to exposed children. It’s important to test the levels of lead in the blood of children if there is a risk of contamination (threshold of 2,5 micrograms per decilitre, but additional expert groups warn that any level of lead has the potential to cause harm). People who were exposed to the highest levels of lead have been the orders at the cathedral itself of course. Tests taken inside the cathedral found levels up to 588 times above the regulatory threshold (threshold is 93 micrograms per square foot). There were differences between the roof and ground floor; also depending on the time post-explosion.

Toxicities of Lead are multiple and can induce several irreversible toxicities.

As an Ocular Pathologist & Toxicologist, I describe hereby the potential ocular toxicities related to lead intoxication.

Ocular toxicities: Inorganic lead poisoning in humans can induce amblyopia, blindness, optic neuritis or atrophy, peripheral and central scoots, paralysis of eye muscles and decreased visual function. Moderate to high level lead exposure produces scotopic and temporal visual system deficits in occupationally exposed factory workers, and developmental lead-exposed monkeys and rats. This lead exposure produces concentration and time dependent alteration in the retina such that higher levels of lead directly and adversely affect both the retina and Optic nerve, whereas lover levels of lead appear to primarily affect the rod photoreceptors and the rod pathway. Furthermore, these retinal and oculomotor alterations were in most cases correlated with the blood lead levels and occurred in the absence of observable ophthalmological changes, CNS symptoms, and abnormal performance scores. Thus these measures of temporal visual function may be among the most sensitive for the early detection of the neurotoxic effects inorganic lead