ILOILO CITY – An initial Department of Health (DOH) toxicology report found out that a type of pesticide known as cypermethrin caused the massive fainting of around 300 students in Antique province last month.
ONE of the more than 300 victims taken to the hospital after inhaling alleged toxins in two schools in Sibalom town, Antique province on July 2, 2025. (Office of Rep. Legarda)
“There was sufficient evidence of environmental contamination by cypermethrin within the school premises, most likely due to airborne pesticide drift compounded by weather conditions,” said Mayor Gian Carlo Occeña of Sibalom town in a statement.
“This indicated airborne dispersal of the substance,” added Occeña, citing a report from the DOH Toxicology Specialty Center at the Western Visayas Sanitarium and General Hospital in Iloilo.
Students of Pis-anan Central Elementary School and Pis-anan National High and Pis-anan Central Elementary School were rushed to hospitals after allegedly inhaling toxic fumes last July 2. Many of the victims described the foul odor as rotten guava.
The toxicology report indicated that the clinical symptoms experienced, including difficulty breathing, extreme chest pains, vomiting, and chills, were “are all consistent with acute exposure to pyrethroid pesticides.”
The toxicology report also found that two students had high level of urinary formic acid. This was a suggestion of a “possible exposure to methanol, a known solvent in certain pesticide and fogging formulations.”
The local government unit (LGU) of Sibalom cautioned that that the toxicology report is not yet final.
“We are still awaiting the results of other environmental samples submitted for laboratory analysis, which are necessary to establish correlation with the toxicological results already obtained,” Occeña said.