DOH: Bohol poisoning due to pesticide, not cyanide

Pesticide, rather than cyanide, was the lethal ingredient in the snacks that killed 28 grade school children in a remote town in Bohol last week.

Health Secretary Manuel Dayrit ruled out natural cyanide in the poisoning of more than 100 children that ate sweets made from cassava flour during their school recess.

A root crop cultivated across the country, cassava contains toxic levels of cyanide. Food processing, such as cooking, reduces the cyanide to harmless levels.

Dayrit said tests conducted by the University of the Philippines (UP) Poison Management and Control Center showed only traces of cyanide but "significant" signs of pesticide poisoning.

"It is very much possible that the food was prepared in an environment that was highly toxic and contaminated with chemical poisons and bacteria," he said.

UP toxicologists Lyn Panganiban and Irma Macanilao said analysis of the snack samples and the reaction of the survivors to treatment suggested carbamate pesticide contaminated the flour used for the snacks.

Carbamate is a common pesticide in farms and households in Bohol and the snacks may have been prepared in an area with relatively high concentrations of the substance, they said.

Dayrit blamed "diarrhea and dehydration secondary to pesticide" for the children’s death. An "infectious agent" could have also triggered the diarrhea, he said.

Dayrit also raised the possibility that the children’s resistance to the poison may have already been weakened by the presence of pesticide in their environment.

Some of the victims, Macalinao said, suffered from "cholinesterase depression." Cholinesterase is an enzyme believed to mitigate the effects of poison on the body.

Dayrit said the contaminated snacks might have pushed the resistance of the children "over the edge."

"They were using pesticide in that barangay. If the children were exposed to pesticide every day, their cholinesterase levels may decrease," he said.

But epidemiologist Troy Gepte said the Department of Health (DOH) still needed to coordinate its investigation with the National Bureau of Investigation (NBI) and other government agencies to determine conclusively how the poisoning occurred.

Unlike the health department, the NBI has still not ruled out the possibility of cyanide poisoning.

NBI Director Reynaldo Wycoco said the agency would release its own findings tomorrow.

"We will try to reconcile our findings through intensified lab experimentation. The DOH are also experts, and we would coordinate with them," he said.

Poor coordination with other government bodies appears to be the bane of the NBI investigation.

Wycoco said a forensic team sent to Cebu failed because of their "limited capability." Another team sent to Bohol was barred from bringing in some of the reagents needed for their laboratory analysis because of lack of clearance from the Philippine Drug Enforcement Agency (PDEA).

An NBI official said the PDEA feared some of the chemicals could be used in the production of illegal drugs.

Wycoco said the NBI would work round the clock in Manila as soon as its forensic experts return to Manila with the blood and organ samples of the dead victims and the vat used to cook the cassava snacks. — With AFP, Evelyn Macairan