Brazilian Teacher Suspects Student of Mercury Poisoning After Months of Symptoms
Dani Cardoso, an artist and instructor at the Oswaldo Cruz University Hospital in Recife, Brazil, suffered from mysterious symptoms including abdominal pain, muscle stiffness, walking difficulties, and urinary problems for several months. Initially attributing these to a worsening of her fibromyalgia, she grew suspicious after noticing small pellets in her water bottle. In May 2025, Cardoso felt a pellet in her throat while drinking, removed it, preserved it, and handed it over to the police.
Cardoso suspected Maria Aparecida Rodrigues de Araujo, a senior student involved in the hospital's "Art in Medicine" social project for about three years. Cardoso recalled seeing Araujo handle her water bottle and display unexplained hostility towards her despite no prior serious conflicts. To investigate, Cardoso left her phone recording in the room, capturing footage in June 2025 that appeared to show Araujo adding a substance to the water bottle. Cardoso reported witnessing similar behavior on two occasions.
Araujo admitted to being the person in the videos but claimed no memory of the events. After the second recording, Cardoso alerted the police, and both women were taken for questioning. Araujo denied attempting to poison Cardoso, but suspicious powder was found in her bag. Forensic analysis detected mercury traces in the water bottle and toxicology tests confirmed mercury in Cardoso’s body. Medical staff estimated the poisoning exposure lasted between eight months and a year.
Cardoso continues neurological and physical therapy while authorities await medical opinions to determine if her symptoms are linked to prolonged mercury exposure. Araujo’s lawyer stated she suffers from several mental health issues, including mild intellectual disability, depression, anxiety attacks, and psychotic disorders. The defense argues the video alone does not prove the substance or ownership of the bottle. An old dispute over a man both women liked also emerged during the investigation, though Araujo claims no recollection. The inquiry, opened in June 2025, remains ongoing, with the Brazilian Civil Police withholding further details during the investigation.
