Thanks to the use of filters collected daily in the west of Paris, we confirm the passage of the lead-laden plume following the fire on the roof and spire of Notre-Dame Cathedral in April 2019. The measured concentrations on the filter (Pb = 1.4 μg m–3), scanning electron microscopy and Hysplit simulation, correspond to an estimate of a few hundred kilograms of lead that would have been volatilized and then oxidized in the form of micronic and submicronic aerosols. The concentrations found in the plume are, however, much lower than those found in the environment in the 1980s and 1990s but are 100 times higher than those found in times prior to and after the fire. The isotopic signature of the plume is almost identical to that of the fine Pb dust found inside the Notre-Dame building. It is different from the isotopic signature of the Parisian atmosphere before and after the fire, but it is similar to that of the atmospheric Pb legacy recorded by peat cores over the last 300 years in France. The presence of very fine lead-bearing particles makes them potentially transportable over long distances after large urban fires. Our study shows the value of daily aerosol sampling to retrospectively trace the plumes of air pollutants from industrial accidents but also from historical monument fires such as Notre-Dame in 2019.
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