She and other scientists determined that domoic acid, a biotoxin that can cause disease and death in humans, caused the sea lions' illnesses and deaths.
In the 1970s they developed a biotoxin derived from the castor-bean plant.
The edema in the dead birds' lungs might be indicative of exposure to a marine biotoxin.
The spike had been filled with ricin – a deadly biotoxin – and punched into his thigh as he walked down the street.
