The Supreme Court of Justice of Buenos Aires province upheld a ruling against Atanor for irreversible contamination of the Paraná River near San Nicolás.
The case began with a complaint filed by the Asociación Civil Cuenca Río Paraná and went through 12 years of judicial proceedings. The province's highest court rejected the company's appeal and confirmed its responsibility for industrial effluents derived from its agrochemical activity.
The ruling found the presence of atrazine above permitted levels, with comprehensive damage to the river, and pointed to insufficient treatment by Atanor to remove those compounds.
The decision also targeted failures in state oversight. According to lawyer Fabián Maggi, who represented the complainant association, the sentence weighed deficiencies in controls by the Water Authority and the Buenos Aires Environment Ministry.
The case has regained relevance due to new findings during 2026. Analyses of samples collected between February and April detected residues of agrochemicals and degradation products linked to the plant's activity in stormwater discharges flowing into the Paraná.
The compounds mentioned include glyphosate, AMPA, atrazine and metabolites associated with that herbicide. One sample recorded extremely high concentrations of Hydroxy-Atrazine.
The environmental conflict is aggravated by the plant's location inside the urban fabric of San Nicolás and close to residential neighbourhoods. In recent years there have also been contamination episodes, problems with water intended for household consumption and an explosion at the plant that forced nearby areas to be evacuated.
Atanor is currently in the process of relocating after the courts ordered the definitive suspension of agrochemical production in San Nicolás. Environmental organisations are demanding that dismantling, cleanup and transfer of production be carried out under rigorous, independent and transparent monitoring.
