In Brazil, the unabated use of dangerous pesticides reminds the world of the harm done by denying reality. Here, as with everywhere else, synthetic pesticides play a crucial role in agriculture by controlling pests and protecting crops. But because of their high biological activity and persistence in the environment, these substances can harm human health and the ecosystem. All too often, they do just that.
Brazil’s former president Jair Bolsonaro, who, many times, criticized COVID vaccines by claiming that they were too untested, set records in the approval of pesticides in the country, including substances banned in other countries because of safety concerns. The approvals ignored both the environmental impact of these pesticides, which themselves harmed farms, and their economic fallout, with possible export boycotts coming from other countries because of the risks of indiscriminate use.
The overuse of dangerous pesticides in Brazil both threatens public health there and serves as a worldwide warning about science denial. During the COVID pandemic, science denial threatened COVID treatments and vaccinations in Brazil while relegating important issues such as pesticide regulation to the background. Pesticides and pandemics may seem like separate issues, but warnings about the toxicity and risks of pesticides, just like calls for vaccinations, come from scientists. If there is no trust in science, warnings about both will be ignored.
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Undoubtedly, the widespread introduction of pesticides after World War II increased food production on a large scale, but it also created environmental and public health problems, as well as dependencies on pesticide use in agriculture. Many developing countries, especially those in the tropical and equatorial zones, have become major food exporters crucial to global food security thanks to pesticides. Some of these substances lack secure regulations to monitor their precautionary use, however.
India best illustrates this paradox: the world’s most populous country faces the growing challenge of feeding its population and increasing food production. As one of the leading global agricultural societies, India’s farmers rely on chemical fertilizers, pesticides, seeds of high-yielding varieties and mechanization. Synthetic pesticides significantly increase agricultural productivity, but they also threaten Indians’ health and their country’s delicate and unique ecosystem.
It’s not only developing countries that face this challenge. California, with some of the world’s strictest pesticide laws, records hundreds of worker poisonings a year. Most poisonings are not known and recorded, demonstrating how difficult it is to control the use of these substances. Even Europe, rigorous in agricultural product import safety, faces growing problems with the use of pesticides and herbicides in urban and ruralareas.
The intense use of pesticides is more pronounced in major producers of agricultural commodities. In recent years the consumption of pesticides in Brazil has surpassed 300 thousand tons annually, which represents a 700 percent increase in the last 40 years.
During the Bolsonaro years, pesticide registration dramatically increased, reaching 1,629 authorizations for new pesticides by February 2022. Bolsonaro’s government promoted flexibilization policies allowing for the accelerated approval of pesticides associated with diseases such as cancer. This approach resulted in the authorization of 550 new pesticides in 2021 and another 26 in 2022. This policy generated concerns about the risks to public health and the environment, especially considering that 37 of these new pesticides are banned in the U.S. and the European Union because of their toxicity. These statistics echo Brazil’s former minister of the environment, Ricardo Salles, who called for relaxing environmental laws amid the distraction caused by the pandemic.
Pioneering such indiscriminate practices is alarming for the entire world: the International Labor Organization (ILO) reports that 385 million acute poisonings and 11,000 deaths from pesticides occur annually in developing countries.
Brazil’s field workers were the first to be affected by these uncaring policies. The main dangers were acute and chronic poisoning, which can cause convulsions, fainting, coma and even death. In addition, workers can develop serious long-term problems such as paralysis, brain and liver damage, tumors and behavioral changes.
But, of course, the entire Brazilian population is affected, too. Foods with a high pesticide load present high health risks, which can result in chronic poisoning and lead to heart problems, neurological disorders, liver damage, carcinogenic effects, hormonal changes and damage to the immune system. Pregnant people face the additional risk of miscarriage and fetal congenital malformations.
Indiscriminate pesticide use contaminates soil, water, and air, compromising biodiversity and harming fauna and flora. In addition, pesticides can reduce water quality (negatively affecting agriculture itself), impacting aquatic ecosystems and harming aquatic life. Pesticides persist in the environment, causing lasting damage to ecosystems, and pose a threat to environmental sustainability.
The new Brazilian government, led by Luiz Inácio Lula da Silva, must reevaluate and reverse this situation. The start of da Silva’s administration raises concerns about the granting of authorizations for pesticides, however. In a period of slightly more than 11 months in 2023, da Silva’s government nearly matched the Bolsonaro’s government’s rate of authorization of these substances. During the 48 months of Bolsonaro’s administration, 2,030 pesticides were authorized, resulting in a monthly average of 42.29. In the first 11 months of the new government, however, 431 pesticides were authorized, with a monthly average of 39.18.
Consider the dangers faced by rural workers, especially the most vulnerable ones, such as farmhands and smallholders, who have limited resources and knowledge to protect themselves from the adverse effects of both mistaken policies regarding pesticides and lies about vaccines. Food safety and public health must be treated as national priorities that demand rigorous and careful measures, and it is essential to adopt more sustainable agricultural practices that reduce the use of pesticides and promote environmental preservation. The effects of the undermining of science are therefore evident in Brazil, where we see two major forms of poisoning: the use of unapproved drugs against SARS-CoV-2 and exposure to pesticides of dubious safety, some of which have been proven to be dangerous.
Globally, Brazil can be a positive or negative demonstration of the benefits of a more harmonious relationship between science, the environment and the growing demand for food. Everyone stands to gain from control of pesticides, and we need to change the perspective on pesticide use. The world’s food security cannot do without the health security of consumers and concern for the environment—nor can public health be assured amid the denial of science. All are intrinsic and aligned issues for the future of humanity.