Coroner Renee Roussel told Radio-Canada the concentration of the chemical DEET (N,N-Diethyl-meta-toluamide) found in the bodies of Noemi Belanger, 25, and Audrey Belanger, 20, both of Pohenegamook, Quebec, was not high enough to be fatal, the Canadian Broadcasting Corp. reported.
Likewise, Dr. Rene Blais of Quebec's poison control center said the amount of DEET found wasn't high enough to be toxic, "let alone a concentration that would be fatal," the CBC said.
A pathologist in Thailand had found the sisters, who were discovered June 15 by hotel staff, likely ingested DEET when they drank a euphoria-inducing cocktail popular among young Thais.
The Canadian officials were unable to say what did kill the Belangers. Results of additional autopsy tests are pending.
The CBC said in the past three years a dozen tourists have died under suspicious circumstances in Thailand and Vietnam.
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