Exposure to lead in outdoor spaces | handles

ANSES received a request from the Ministries responsible for Health and Labor to characterize exposure to lead via contaminated dust deposited on the surfaces of outdoor public spaces: sidewalks, roads, street furniture, outdoor playgrounds, etc. Indeed, lead can be emitted into the air by industrial or artisanal sites, then be deposited in the environment. It can also be found in dust due to erosion or leaching of architectural elements containing it, and contaminate outdoor spaces in this way. Contamination can finally be linked to accidental pollution, as was the case during the fire at Notre-Dame de Paris in April 2019.

Populations at risk identified

There are few data in the scientific literature concerning the exposure of the general population and workers to lead present in the dust deposited on the surfaces of outdoor spaces. The few available data, including some from French studies, indicate that contamination of this environment can impact blood lead concentration called blood lead.

The populations most at risk of being contaminated by dust are children and certain workers, due to their likelihood of contact with contaminated surfaces. The priority route of exposure seems to be the ingestion of dust, in particular for children who are more likely to put their hands in their mouths.

Thus, the Agency concludes that the dust deposited on the surfaces of outdoor public spaces should be considered as a source of exposure, with particular interest for places frequented by children.

Assess exposure related to ingestion of contaminated dust

In its expert appraisal, ANSES notes that the various current calculation models and that the available data do not allow a robust assessment of exposure to lead via external dust. It is therefore not possible to assess the contribution of this source of lead exposure relative to all the others: food, drinking water, indoor dust, air, etc. Nevertheless, ANSES emphasizes the importance of reducing exposure to outdoor dust without delay.

In its recommendations, the Agency mentions the need to acquire data that will make it possible to model the exposure to lead present in the dust deposited on the surfaces of outdoor public spaces.

Reduce lead exposure from ingesting outdoor dust

For the general population, the Agency recalls the prevention actions recommended by the High Council of Public Health (HCSP) in 2017 such as frequent hand washing, or taking off your shoes to limit the transport of dust into the accommodation. For vulnerable populations at increased risk of contamination, in particular children, it is recommended to have the lead in the blood measured (blood lead).

For workers exposed to outdoor dust, given the diversity of situations, ANSES first recommends measuring blood lead levels to estimate exposure. Furthermore, the Agency recommends updating the biological values ​​to be used, in accordance with its opinion of July 2019 (PDF). Finally, the Agency specifies that workers who perform tasks likely to put them in contact with lead dust deposited on the ground or other contaminated surfaces should benefit from reinforced individual medical monitoring.

More specifically concerning the post-fire situation at Notre-Dame de Paris, the results of this ANSES expert appraisal will be used as part of the approach initiated under the aegis of ARS Île-de-France, aimed to document the usual lead concentrations in outdoor dust in Paris.