(Rennes) A statistical link has been established between occupational exposure to pesticides and the risk of developing acute myeloid leukemia, the most common and most serious in adults, according to a study by the Tours Regional University Hospital Center.
In this study published in Scientific Reports, four hematologists analyzed for two years the scientific data published between 1946 and 2020 in three large global databases.
“From a keyword search, we identified around 7,000 references, from which we pulled 190 articles. By using international scientific standards of analysis, 14 of these studies were chosen to be analyzed within the framework of a “meta-analysis”, corresponding to some 4000 patients and 10 000 controls ”, explained to AFP Olivier Hérault, head of the biological hematology service at the CHRU.
High dose pesticides
“We found a statistical link between exposure to high-dose pesticides and the risk of acute myeloid leukemia. This link is a relative risk of 1.51, which means that compared to an unexposed population, this exposure increases the risk of developing this type of leukemia by 50% ”, continues the researcher.
The study also establishes a “stronger” link with insecticides and disease than with fungicides and herbicides, and also a stronger link in Asia and the United States than in Europe. These are products used by professionals, especially farmers, in high concentrations.
The study did not reveal any mode of exposure. Until now, medical research has shown a link between high exposure to pesticides and the development of “preleukemic” states, but not with the increased risk of developing acute myeloid leukemia, the CHRU said in a statement.
“Reinforce prevention messages”
According to Professor Hérault, “these results add a risk factor to acute myeloid leukemia which was not demonstrated, but simply suspected”. This study should reinforce, according to him, “the messages of prevention towards the users”, can “feed the reflection on the distances between areas of spreading and dwellings” and bring an element of reflection “for the recognition in occupational disease for farmers ”.
If an epidemiological link is established, the study does not demonstrate a causal link. “This is part of the research we are doing,” says Hérault.