Paris authorities began decontamination work around Notre Dame on Tuesday, closing off streets surrounding the scorched cathedral.
High levels of lead were registered in the area around Notre Dame after the April fire that destroyed the cathedral's metal and wood roof. The roof and the spire contained several hundred tons of the toxic metal, according to French media.
Read more: Paris official reassures public about Notre Dame health risks after lead scare
The massive cleanup operation inside the cathedral was suspended last month for safety reasons. However, lead levels of 400 to 700 times the official health limit had been found on the ground around the cathedral after the fire, according to a report from investigative news website Mediapart in July.
Residents near the cathedral have been advised to have their blood tested for lead. Two children have so far tested positive for a high blood lead level, though one of the cases could be attributed to lead pollution in the family's home.
Multiple decontamination efforts
Police blocked off two streets and a bridge around the cathedral as part of the decontamination mission, installing high fences to keep both Parisians and tourists out.
Authorities have launched multiple lead prevention operations, namely cleaning up neighborhood schools, detoxifying surrounding streets and setting up stricter new decontamination procedures for experts working inside the cathedral.
According to the culture ministry, there will be two decontamination techniques used for the surrounding neighborhoods. One method will feature high water jets with chemical agents. The other involves spreading gel on fixtures that absorb lead, such as public benches and street lights, and letting it dry for several days before removing it.
Read more: Future of Notre Dame Cathedral wide open
Meanwhile, a separate new decontamination zone is being set up for workers who have been clearing hazardous wreckage from inside the cathedral to ensure that there is no pollution outside the site. Authorities expect that zone to be ready next week.
dv/se (AP, dpa)
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