Federal Public Prosecutor’s Office v. Syngenta Protection of Crops Ltda. and others (Environmental damage caused by pesticides containing atrazine)

On November 18th 2025 the Federal Public Prosecutor's Office (MPF) filed a Public Civil Action (environmental class action), with a request for a preliminary injunction of a precautionary and inhibitory nature, against Nortox SA, Syngenta Proteção de Cultivos Ltda., several other companies, and IBAMA, due to environmental damage resulting from soil and water pollution caused by pesticides. The pesticides in question contain the active ingredient atrazine and are produced, imported, or marketed by the defendant companies, whose environmental monitoring of residues must be adequately promoted by the environmental agency. The widespread use of atrazine in Brazilian agriculture and the controversies and serious environmental and health concerns that its use brings with it are highlighted. Atrazine is banned in 44 countries (including the entire European Union), and exposure to the substance is associated with a range of deleterious effects on human health. In addition to its intrinsic toxicity, it is noted that atrazine has high persistence in the environment (once applied, the substance does not degrade easily) and high mobility in the soil, being transported to rivers and groundwater. The playintiff cites technical reports from Embrapa documenting the results of using the product in the Dourados River Hydrographic Basin in Mato Grosso do Sul, an area of intense agricultural activity where crops such as soybeans, corn, and sugarcane occupy more than half of the territory. The scientific studies highlight that the presence of atrazine and its degradation products (metabolites) is not restricted to the area of its application and that there is a shortcoming in CONAMA Resolution 357/2005, as it does not establish maximum permitted values. Tha plaintiff states that technical assessments have confirmed the presence of atrazine and its derivatives in multiple water sources of various indigenous communities affected by agribusiness activities in the state. It explicitly states that the damage caused by the use of pesticides is not distributed neutrally and disproportionately affects rural workers, Afro-descendant populations, indigenous peoples, traditional communities, and vulnerable riverside populations, characterizing a pattern of environmental racism expressly repudiated in the Belém Declaration (2025) and incompatible with the duties of equality and non-discrimination in environmental and climate matters. It clarifies that the situation of chemical contamination must be interpreted in light of the commitments made by Brazil in the aforementioned declaration, which recognizes that historical and persistent patterns of discrimination, coupled with unequal access to decision-making processes, produce differentiated exposures to pollution, climate risks, and nature loss. It argues that Advisory Opinion (AO) 32/2025 of the Inter-American Court of Human Rights, although focused on the climate emergency, provides a legal roadmap directly applicable to large-scale chemical environmental damage, establishing guidelines on due diligence and the regulation of business activities. According to the Federal Public Prosecutor's Office (MPF), the conduct of the defendants and the state's omission in controlling and monitoring atrazine conflict with the duty of enhanced diligence, precaution, and corporate transparency established in AO 32/2025, which reinforces the need for accountability, the adoption of structural measures for full reparation, cessation and non-repetition, and correction of a structural pattern of disproportionate exposure of vulnerable groups to chemical contamination. Furthermore, the MPF highlights the aggravation of the damage due to the ineffectiveness of traditional water treatment methods, exposure to the product in the workplace, the finding of its use in the production of crops, and the risk assumed by the defendant companies in imposing a long-term contamination on society and the environment. In preliminary proceedings, the granting of provisional urgent relief is requested to order the defendant companies to (i) present a detailed work plan for the complete diagnosis of the contamination of the Dourados River Hydrographic Basin; (ii) have their assets frozen in the amount of R$ 300,000,000.00; and that IBAMA implement a pesticide residue monitoring program in the Dourados River. On the merits, the defendants are jointly and severally liable for (i) the implementation of a Degraded Area Recovery Plan to remediate/mitigate atrazine contamination in the soil and waters of the river bbasin, (ii) payment for collective moral damages and irreversible environmental damages, in the amount of R$ 300,000,000.00 and, specifically in relation to IBAMA, that the agency be obliged to immediately implement environmental monitoring programs for atrazine and initiate the procedure for reassessing its registration.