A local medical doctor, a marine ecologist, and oyster farmers are raising an alarm that a nearby monoculture plantation of Eucalyptus nitens may be poisoning local water reserves, leading to rare cancers and high oyster mortality in Tasmania. However, the toxin is not from pesticides, as originally expected, but appears to originate from the trees themselves.

“The toxin is actually coming from the monoculture trees,” Scammell said on Australian news show, Today.