PARIS, France - French art experts headed into the stricken Notre-Dame cathedral in Paris to remove all the remaining paintings on Friday despite warnings from an environmental group that the site could be a toxic health threat.
Officials from the culture ministry were allowed into the 850-year-old landmark to begin retrieving the artworks after fire service officials declared the scorched structure safe enough to go inside.
Firefighters and engineering experts have been working on the fragile landmark since a devastating blaze on Monday night, erecting scaffolding and other wooden supports to stop any of the stonework collapsing.
"The paintings inside the cathedral have been saved from the flames and can now be taken down and transported to safe areas," France's Culture Minister Franck Riester told reporters at the scene on Friday.
"All of the paintings will be removed today," Riester added, saying that he was feeling "very positive" given how most of the priceless canvasses, many of them dating from the 17th or 18th century, had been saved.
As firefighters inspected the top of the fragile southern facade, art experts began carrying out paintings from the cathedral in protective white film and loading them into trucks.
The artworks were taken to the Louvre museum, a center of restoration, where experts will repair relatively minor damage caused by smoke or water before storing the paintings until they can be returned.
But as the latest phase of salvage work took place, a French charity warned about the possible health impact from the fire.
The Robin des Bois (Robin Hood) organization said that around 300 tons of lead from the roof and steeple had melted in Monday night's fire, which according to officials had reached 800 degrees Celsius (1,470F) at its peak.
"The cathedral has been reduced to the state of toxic waste," the association said in a statement, calling on French authorities to detoxify the tons of rubble, ash and waste water produced by firefighters.
"Before launching a competition for the design of a new steeple, we should launch a competition to decontaminate what at the moment, alas, can be considered an industrial wasteland," it added.
After fears about air-borne lead pollution on Monday night, monitoring service Airparif told AFP it did not monitor lead levels in real-time but it has sent its filters to be analyzed in a laboratory.
There was no immediate reaction from French authorities to the claims by Robin des Bois, which are of most concern to people living and working on the Ile de la Cite island where Notre Dame stands.
Lead pollution can cause neurological defects for humans, especially children, as well as nervous system and kidney problems.
Thanks to a human chain formed by firefighters and church officials on Monday night, the vast majority of the most sacred artifacts and valuable items inside the cathedral were saved.
These include the Holy Crown of Thorns, which Catholics believe was worn by Jesus Christ at his crucifixion, and a tunic thought to have belonged to 13th-century French crusader king, Louis IX, who was made a saint.
Even a copper statue of a rooster containing relics that sat atop the now-destroyed Notre-Dame spire was found among the ashes, dented but intact.
The paintings being brought out on Friday included several of the great "Mays" paintings, which were commissioned between 1630 and 1707 by the Corporation of the Parisian goldsmiths.
The giant canvasses, as big as three meters by four (10 feet by 13), depict events from the life of the Virgin Mary and were offered to the cathedral every May 1 as a sign of devotion.
As the work went on inside Notre Dame, crowds of Parisians and tourists continued to swarm to the scene, sitting on the banks of the river Seine to observe the cathedral walls, blackened in places, which now stand without a roof.
President Emmanuel Macron welcomed a delegation of officials from the UN's cultural agency UNESCO on Friday to discuss offers of aid from other countries to help restore the beloved emblem of France.
He was accompanied by army general Jean-Louis Georgelin who will oversee the process and has likened his new job to a "combat mission."
Macron has set a five-year deadline to rebuild the architectural marvel, which took around 200 years to build originally from when construction work started in the 12th century.