These Chinese Field Epidemiology Training Program (FETP) residents were in the process of registering marine puffer fish samples collected during an investigation of an outbreak of tetrodotoxin poisoning in August, 2012, in Guangdong, a coastal province of southeast China.
”Tetrodotoxin is an extremely potent poison (toxin) found mainly in the liver and sex organs (gonads) of some fish, such as puffer fish, globefish, and toadfish (order Tetraodontiformes), and in some amphibian, octopus, and shellfish species. Human poisonings occur when the flesh and/or organs of the fish are improperly prepared and eaten. Tetrodotoxin interferes with the transmission of signals from nerves to muscles and causes an increasing paralysis of the muscles of the body. Tetrodotoxin poisoning can be fatal.”
See the links below, for more information on tetrodotoxin, or the FETP.