Tietê River contamination reveals high levels of drugs and pesticides

Research from the 2025 Tietê Expedition, conducted by SOS Mata Atlântica and four public universities, indicates that no section of the Tietê River is free from contamination. Findings include the presence of cocaine, microplastics, and 25 types of pesticides. Notably, atrazine, a herbicide banned in the European Union since 2004, was detected above legal limits in several stretches. The river's six major reservoirs, which provide water and energy to millions of people, are affected by these pollutants.

Additionally, researchers from the University of São Paulo (USP) identified fentanyl in the saliva of individuals using synthetic cannabinoids, commonly known as K2 or K9. The study, published in the journal Drug and Alcohol Review, found the opioid in 32% of participants. The presence of these substances in the environment and in synthetic drug mixtures highlights significant public health risks, including potential respiratory depression and fatal overdoses.