A 27-year-old woman died Saturday after experiencing a reaction during a swimming lesson in São Paulo, Brazil, with authorities investigating a possible pool chemical poisoning. Juliana Faustino Bassetto, along with her husband and 14-year-old child, began to feel unwell during the lesson after noticing an unusual smell and taste in the water.
The incident occurred at the C4 GYM Academy in the east zone of São Paulo. According to reports from g1.globo, the family alerted their swim instructor to their concerns, prompting the evacuation of all students from the premises. Juliana and her husband were subsequently rushed to hospital, where Juliana’s condition rapidly deteriorated, leading to cardiac arrest and her eventual death.
As of Monday, February 9, 2026, Juliana’s husband remains hospitalized in serious condition. Their 14-year-old child is receiving treatment in intensive care. Two other individuals who visited the pool also reported feeling unwell but have since been discharged from medical care.
Police investigators discovered a bucket containing approximately 20 litres of a potentially poisonous chemical mixture at the scene. The substance is currently undergoing analysis to determine its composition and the cause of the contamination. The gym and pool facilities have been closed by health authorities pending the outcome of the investigation.
Authorities are investigating whether the incident was caused by improper handling or mixing of chemicals used for pool maintenance. According to Detective Alexandre Bento of the 42nd Police Precinct, initial forensic findings suggest a chemical reaction occurred, contaminating the air and causing the poisoning. “We are trying to locate those responsible, the professor who was teaching the class. Witnesses said that the valet was the one mixing the products,” Bento told TV Globo.
The C4 GYM Academy released a statement indicating full cooperation with the authorities. The statement, as reported by The Sun, affirmed the academy’s commitment to providing all necessary assistance in the investigation.
The incident raises concerns about safety protocols and regulatory oversight at recreational facilities in Brazil. Reports indicate the gym allegedly lacked the necessary operating licence, potentially highlighting systemic issues in enforcement and compliance.
Pool chemical injuries are a recognized public health concern globally. According to data from the U.S. Centers for Disease Control and Prevention (CDC), pool chemical injuries led to an estimated 13,508 emergency department visits in the United States between 2015 and 2017. Approximately one-third of these injuries occurred in individuals under the age of 18. The CDC’s Model Aquatic Health Code provides guidelines for preventing such incidents, emphasizing safe handling and storage of pool chemicals.
This incident echoes similar cases reported internationally. In October 2025, an Islander was left fighting for her life after being poisoned by jacuzzi chlorine tablets, prompting a warning about the dangers of pool chemicals, as reported by Jersey Evening Post. These cases underscore the potential for severe health consequences resulting from improper chemical management in aquatic environments.
The investigation in São Paulo is ongoing, with authorities focused on identifying the specific chemicals involved, determining the cause of the contamination, and holding those responsible accountable. The tragedy serves as a stark reminder of the importance of stringent safety measures and regulatory compliance in maintaining the health and well-being of individuals utilizing recreational water facilities.
