Paris scrambles to allay Notre-Dame lead poisoning fears

Paris officials moved Tuesday to downplay the risk of lead poisoning from the massive fire that tore through Notre-Dame cathedral in April, as tests continue to show worrying levels of the toxic metal at nearby schools.

"All the tests we've carried out in a radius of 500 metres (1,640 feet) around Notre-Dame are negative, meaning there is no danger," deputy mayor Emmanuel Gregoire told LCI television.

Hundreds of tonnes of lead in the roof and steeple melted during the April 15 blaze, which nearly destroyed the gothic masterpiece, releasing lead particles that later settled on surrounding streets and buildings.

Work at the gutted monument was halted on July 25 after officials found that anti-contamination measures were insufficient to keep the lead from spreading, and is only expected to resume next week.

On Monday evening, the city posted the results of a new round of testing at the schools and daycares in the immediate area, showing less than 70 microgrammes per square meter, the level generally considered safe.

But it also revealed that some schools and daycare centres beyond the 500-metre perimeter still showed isolated readings on playgrounds or windowsills of more than 1,000 microgrammes.

Gregoire vowed the sites would be "rigorously cleaned" before the school year resumes in September, and would welcome children only if approved by the regional health agency ARS.

"The city is not going to take any risks," he said.

But he rejected calls by some residents and parent associations to shroud the entire church site with protective cladding to contain the particles, a system often used when removing asbestos.

"From a technical and financial point of view, such a move would be an incredibly complex decision to carry out," Gregoire said.

After weeks of saying residents were not at risk, Paris authorities suddenly shut two schools on July 25 that were running summer holiday programmes for children after tests found dangerous lead levels.

That prompted a lawsuit from an environmental group alleging that officials failed to quickly contain the contamination risks, while others accused the city of failing to notify the public about the alarming test results.

As recently as June 5, tests were showing lead readings of up to 7,500 microgrammes per square meter on streets one kilometre away from Notre-Dame, according to a map of ARS results published by Le Parisien newspaper Tuesday.

Ingesting lead particles can cause neurological defects as well as nervous system and kidney problems, according to the World Health Organisation.

Small children in particular are the most vulnerable, since they are more likely to touch contaminated objects and then put their fingers in their mouths.