Florida green water snakes pose minimal health risks to humans. Their saliva contains mild toxins that help subdue amphibian prey but is not medically significant to humans beyond minor swelling. Musk secreted when threatened is foul-smelling but harmless.
While non-venomous, green water snakes can bite if severely provoked with their small, rear-facing teeth. These defensive bites rarely break skin and do not transmit any diseases. The snakes are not known to carry salmonella or other zoonotic pathogens.
Green water snake populations provide an important check on disease-carrying mosquitoes by preying heavily on the aquatic larval and pupal stages. By reducing mosquito numbers, the snakes may lower human risk of contracting vector-borne ailments like West Nile virus.
On rare occasions, green water snakes may prey on larval salamanders containing enough tetrodotoxin to become toxic but this poses no direct risk to humans. Overall, the Florida green water snake is harmless to people and helps control pests.