Living and working in an environment laden with chemicals and pollutants is harmful to your health. In particular, pesticides used in agriculture, even when considered individually safe, when mixed together in the environment would seem to increase the risk of developing cancer. This is suggested by international research published in the magazine Nature Healthwhich analyzed the link between chemical use and human health on a national scale in Peru, between 2014 and 2019.
The perfect country
The choice of Peru as the study area was not random: the country has a varied geography, has intensely cultivated areas with high use of pesticides, but also less polluted rural areas, metropolises and uncontaminated natural ecosystems. Indigenous and rural communities were found to be those who coexist most closely with pesticides: in these communities, an average exposure to 12 different chemical substances in high concentrations emerged.
Common substances, believed to be harmless
The study focused on a group of 31 common substances which, although not classified by the WHO as proven carcinogens, could have cumulative harmful effects in the event of multiple exposure (the so-called “cocktail effect”). “First, we modeled the dispersion of pesticides in the environment over a six-year period, from 2014 to 2019,” explains Jorge Honles, an epidemiologist at the University of Toulouse who participated in the study. “This allowed us to create a high-resolution map and identify areas with the highest risk of exposure.”
The environmental exposure maps were then cross-referenced with the health data of over 150,000 cancer patients registered between 2007 and 2020. The data that emerged outline an unequivocal correlation: the density of pesticides in the environment directly reflects the incidence of specific oncological diseases in the area. In critical areas, the risk of falling ill undergoes a dramatic surge, with an average increase of 150%.
New regulations are needed
The research also documented the presence of specific biological alterations in patients coming from areas where they had been exposed to pesticide mixes. It is therefore no longer a question of a simple statistical suspicion, but of clues that indicate that environmental pollution with mixtures of otherwise harmless substances can trigger molecular mechanisms that give rise to cancer.
The findings call into question current international safety standards. Traditionally, in fact, health authorities evaluate the toxicity of one substance at a time, establishing safety limits based on isolated exposures. However, the reality of agricultural fields and surrounding areas is composed of complex mixtures that interact with each other in ways not yet fully considered by regulations. The study suggests that a pesticide judged safe when analyzed individually can become dangerous when added to other chemical agents.