Work at the site of France's damaged Notre Dame Cathedral resumed on Monday, after a three-week pause over concerns about lead that spewed from the fire in April.
As the blaze ripped through the 850-year-old cathedral's roof and steeple, smoke billowed out — its yellow hue a sign of burning lead — spreading toxic dust that settled on streets, homes, businesses and schools in parts of central Paris.
A cleanup of Notre Dame's plaza and surrounding streets began Aug. 13, and Paris police chief Michel Cadot says it will last until Sept. 10. The process involves vacuuming and scrubbing the pavement, using a high-pressure hose to rinse the ground with chemicals and recovering the wastewater. In some spots, a special gel is applied and then removed after hardening, taking harmful particles with it.
New decontamination measures are in place for workers at the cathedral. But environmental associations, labor unions and other groups say authorities should have started the cleanup months ago, and they are worried that health risks may persist in parts of Paris.
The fire melted some 440 tons of lead contained in the roof and spire, estimates Jacky Bonnemains, president of environmental protection group Robin des Bois, citing research on archives and historical documents.
Last month, Robin des Bois filed a lawsuit against authorities, claiming officials failed to quickly contain the contamination. The organization, along with labor unions and other groups, also accuses officials of downplaying the severity of the risk.
"We believe the priority was to not hinder the economy and business in the historic quarter of Paris," Bonnemains said.
After the fire broke out on April 15, police said the risk of lead exposure was "very localized." Areas including the cathedral's plaza and gardens were already blocked off to the public. The authorities advised area residents to use wet wipes to get rid of dust.
In May, officials assured the public that air quality around Notre Dame was not toxic, and Paris air quality watchdog Airparif said pollution was not abnormal the day after the fire. But Bonnemains said authorities should have informed tourists and locals more about the risks of lead pollution.
On a recent day before the cleanup began, pedestrians could still walk up to the edge of the barricaded plaza in front of Notre Dame. Visitors were taking photos and families were sitting on the ground outside the damaged cathedral.
Cordelia Drew, who was visiting from London, said she didn't know there was lead pollution and would have appreciated an advance warning.
"Honestly, if I knew about it, I'd probably do some research," she said. "If it was serious enough I would have had a second thought about [coming to Notre Dame]."
Bonnemains said the lawsuit has raised important local public awareness about the danger of lead exposure caused by the fire, but he is not sure what the outcome will be. The Paris prosecutor will have to decide whether to open an investigation based on the claim and evidence submitted by the organization.
Employees at surrounding cafes and souvenir shops, notably on the rue du Cloître-Notre-Dame that runs along the cathedral's northeast wall, tested negative for lead contamination in June, radio network France Inter reported, and lead tests at schools and day care centers in the immediate area just after the fire showed low levels of the metal and were cleaned, according to Paris city officials.
But suddenly last month, the city temporarily closed two schools in nearby neighborhoods outside the immediate vicinity of Notre Dame. Authorities found hazardous levels of lead particles at the facilities.
After the closures, Paris Deputy Mayor Emmanuel Grégoire told TV news channel LCI that schools would be thoroughly cleaned and tested before students return in September. He insisted there had been "no health risk" and it was just "more convenient" to close the schools to start decontamination.
A report from a regional health agency earlier this month said 16 children of 175 tested since the fire showed blood lead levels that needed to be monitored but did not qualify the cases as lead poisoning. Two children showed blood lead levels above the threshold considered to be safe. In one of the cases, officials were examining whether it was linked instead to lead that could already have been present in the child's home.
According to the World Health Organization, there is no known level of lead exposure that is safe. It says that young children are more vulnerable to lead poisoning, which can cause damage to the brain and nervous system.
French authorities have focused mostly on the immediate area around Notre Dame, but they recently turned their attention to neighboring districts. When Notre Dame caught fire, wind from the east blew the smoke to Left Bank neighborhoods southwest of the cathedral.
Inspectors recently visited businesses just across the river on the Left Bank near the Place Saint-Michel. Pascal Londais, owner of La Fontaine Saint Michel, is waiting for the results of lead tests conducted at his cafe.
His staff might have to get blood tests if lead is found there. Although Londais says he is not worried, he thinks authorities waited too long to alert businesses and run tests.
"They should have intervened more quickly," he said. "Fifteen days, three weeks ... 'Hey, there's lead. We're going to take care of this immediately.' Not three months later."
As for the reconstruction workers, new protocols include decontamination showers and protective suits to be left on-site. Officials have rejected calls from environmental and labor groups to seal off Notre Dame in plastic to prevent more lead dust from escaping.
Annie Thébaud-Mony, the research director at the National Institute for Health and Medical Research, told French radio RTL earlier this month that lead contamination at Notre Dame is a "health time bomb."
"We have to realize that the 400 tons of lead that were spread correspond to nearly four times the annual lead emissions in all of France," said Thébaud-Mony. "Lead is the equivalent of asbestos in terms of toxicity."
Bonnemains, a longtime environmental and human rights activist from the group taking legal action, said lead pollution from the Notre Dame fire will remain in Paris for years to come — and that the Seine River will spread it even beyond the city to estuaries and the English Channel.