Study: Pesticides May Be Behind Cuba Embassy Sonic Attacks

A study commissioned by the Canadian government says the high-pitched sounds and other symptoms associated with suspected "sonic attacks" on almost 40 U.S. and Canadian embassy personnel working in Cuba could have been caused by a neurotoxic agent that kills mosquitoes. 

Researchers for the study, commissioned through Global Affairs Canada, identified a region of the brain responsible for concentration, memory, and the sleep cycle and examined how that section could be injured, reports Canada's CBC News.

"There are very specific types of toxins that affect these kinds of nervous systems ... and these are insecticides, pesticides, organophosphates — specific neurotoxins," said Alon Friedman, the study's lead author. "So that's why we generated the hypothesis that we then went to test in other ways...the working hypothesis actually came only after we had most of the results," 

Toxicology reports of the Canadian victims confirmed the presence of two agents found in insect fumigation products, pyrethroid, and organophosphate. 

For the study, doctors, scientists, and researchers assessed the Canadian diplomats' symptoms, and detected different levels of brain damage, finding that a key enzyme, cholinesterase, which is needed for the brain's functions for the nervous system, was being blocked. 

They also noted that some classes of pesticides inhibit cholinesterase and that in 2016, Cuba had launched a campaign against mosquitos in response to the Zika virus. Later that year, embassy personnel started seeking care for hearing loss and concussion-like symptoms. Investigators suspected they'd been attacked with some sort of sonic waves, but Cuba denied the accusation. 

Friedman said it is not known if the Cuban population was affected by the fumigations, but his team will work with scientists there to examine those topics to try to confirm toxic levels. 

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