More than 1,000 chemicals used in agriculture They are causing the decline of insect populations, animals that are essential for the health of the planet as they are responsible for the pollination of many plants and a fundamental link in the food chain.
Scientists from the European Molecular Biology Laboratory (EMBL) have verified how more than 1,000 “agrochemicals” impact, even in doses that are not lethal, on insect populations and how they very negatively affect their development and behavior and offer avenues to improve chemical safety assessment, environmental protection, food safety, and animal and human health.
The work, which is published today in the journal Science, concludes that the most harmful effects of agrochemicals (such as herbicides or pesticides) are aggravated when the environmental temperature increases and that The decline in insect populations can be estimated at an average of between 2 and 3 percent each year.
The researchers systematically exposed fruit fly larvae to more than 1,000 molecules contained in chemicals, and found that 57 percent of the chemicals altered their behavior in a significant way, even in amounts that were not lethal, and that higher levels of chemicals compromised their long-term survival at the same exposure times.
Key to the balance of ecosystems
Insects play a crucial role in maintaining the balance of ecosystems and As their populations decline, so does genetic diversity.essential for species to adapt to current and future environmental changes.
Researcher Justin Crocker, group leader at the EMBL institute in Heidelberg (Germany), has observed that in addition to agrochemicals there are other “key” factors that aggravate the situation, and has cited climate change, the destruction of habitats or the loss of biodiversity.
“Rising temperatures increase the toxicity of pesticideswhile urbanization and deforestation reduce insect habitats, and light pollution and the spread of invasive species contribute even more to the crisis,” Crocker told EFE.
Although all these factors aggravate the situation, Argentine researcher Lautaro Gandara – first author of this work – has stressed to EFE that the measures necessary to counteract and reverse the process must be directed against the causes of the problem, not against secondary factors.
Crocker has observed that The decline in insect populations would appear to be more severe in those regions of the world where agriculture is more intensive.such as Europe and North America, where the use of agrochemicals is high and where the phenomenon has been studied in more detail, but has ensured that tropical regions, very rich in insect biodiversity, are also in danger due to deforestation and agricultural expansion.
And Lautaro explained that severe reductions in insect biomass have been reported in northern continental Europe and southern Great Britain. “However the phenomenon appears to be global, with examples coming from both industrialized regions and protected areas, and from the Arctic to the tropics.”
Ending agrochemicals, not so easy
But when asked if it would be easy, and advisable, to do without most of these chemicals, Justin Crocker answers “not at all”, since some of these pesticides are essential for food safety.
“However, There are safe alternatives, such as biological controls and integrated pest managementwhich are advisable. A total ban can disrupt food production, but reducing the use of highly toxic chemicals is possible and necessary,” confirmed the researcher.
In this work, the researchers have shown that it is possible to monitor the “sublethal” effects in a robust, efficient and economical way, and the Argentine scientist has explained that the incorporation of similar tests when testing the environmental impact of an agrochemical “will allow us to discriminate with greater rigor to the molecules that are safe from those that are not.”
Although the problem is global, scientists have highlighted that local regulations “can make a difference” and have cited as an example how European restrictions on a type of insecticides (neonicotinoids) have contributed to the recovery of pollinators, but they have insisted where global coordination is essential to prevent transboundary pollution and ensure widespread protection.