About 10% of childhood cancers are linked to genetic mutations. 90% of these cancers are linked to environmental factors. ” Very few teams are working on a developmental origin of childhood cancers» introduced Laurence HUC, INRAE research director at the Interdisciplinary Science Innovations and Societies Laboratory and at the Health, Environment and Work Research Institute (IRSET). “It is unclear whether exposure to toxic products in-utero during pregnancy or exposure during childhood and adolescence is a risk factor for pediatric cancer.explains Laurence Huc.
Pediatric cancer: an accumulation of environmental risk factors
Laboratory analyzes on animal models show that the exposures which increase the number of neoplasias (cancers) are exposure to electromagnetic fields, ionizing radiation, chemical substances such as hydrocarbons, dioxides, pesticides, exposure to lead and, during pregnancy, to endocrine disruptors. These exposures will add up. Data collected, among others, by Laurence Huc’s team on pediatric cancer cluster sites have revealed an accumulation of risk factors “On the Sainte-Pazanne site (Loire-Atlantique), children are exposed to pesticides, electromagnetic fields, heavy road traffic in the area. The sector also includes industries in which radioactivity is handled and this area south of Nantes is perhaps exposed to pollution linked to the petrochemical activity of Saint-Nazaire.says Laurence Huc.
When are pollutants dangerous?
“It is not only the accumulation of these exposures or the quantity received that counts but also the moment in the life of the child when this exposure will be made.informs Laurence Huc. “The window of susceptibility i.e. the time of exposure may influence or reinforce exposure associationsexplains Vincent Bessonneau, director of the Department of Environmental Health Sciences at the EHESP (Ecole des Hautes Etudes en Santé Publique). Laurence Huet gives an example of the importance of this window of exposure: if a child is exposed to a chemical substance which mimics a key hormone while the ovaries of this little girl are forming, it can lead to cancer of the the ovary.
How to limit the impact of environmental causes on pediatric cancers?
The teams working on this subject will set up more in-depth studies in a multidisciplinary way with the EHESP and in partnership with citizens’ associations to better characterize this pollution and be able to put in place preventive measures in order to be able to protect families. . This could, for example, involve a more rational use of pesticides, the diversion of high-voltage lines, the decontamination of industrial sites…”This research carried out on these territories as well as on a larger cohort with biological monitoring will allow us tostudy the link between certain pollutants and certain cancersinforms Vincent Bessonneau. He stresses that all this research requires funding over a long period of time and that it is important to intensify studies on the mechanisms and factors that can trigger pediatric cancers. These affect each year, in France, nearly 2,500 children and adolescents, half of whom are under five.
* They spoke at the symposium “Pediatric cancers, from causes to treatments” Wednesday, June 7, in Paris
