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What are the dangers of bathing and related activities?


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Beware of venomous animals

published on 04/16/2008

Sea envenomation is rare provided that bathers behave appropriately in and below the water. In the waters along mainland France, few venomous species can be found. Some species may, however, be responsible for envenomation. In contrast, tropical waters are home to a far larger number of venomous species, which are often much more dangerous than the mainland species. If you bathe in any of France’s overseas departments (Guyana, Reunion, Guadeloupe and Martinique), take greater care!
Envenomation risk applies mainly when bathing in the sea (there are very few venomous species in freshwater). Most frequently, envenomation occurs through a sting (weever fish, rockfish, stingray) but can also result from a bite (moray eel) or mere contact with rash-inducing species like jellyfish.
Recommendations for preventing envenomation or treating accidental envenomation:
  • Wear sandals and protective clothing; heed the basic safety instructions when observing underwater fauna and flora if you are a deep-sea diving enthusiast, as this is where the venomous species can be found. In the overseas departments, in particular, ask about the local fauna and its potential hazards before entering the water.
  • Beware of jellyfish that wash upon the beach: even when they are dead and out of the water, their venom can remain active for several hours!
  • Carefully clean and disinfect any wounds. The use of antibiotics is recommended. The physician may also advise you to check that you have been given the tetanus vaccine, and repeat it if necessary.
  • Apply heat to the affected part of the body, as the venom of many species is heat-sensitive.
  • Apply an anti-inflammatory cream locally.
  • If symptoms persist or worsen, do not hesitate to seek medical advice.
More information:

A large number of marine animal species with a venom apparatus have been identified in all of the world’s oceans and seas. The venom apparatus acts as a defence system, intended to prevent or ward off potential predators, or as an attack mechanism. Varying in set-up depending on the species, it is generally composed of venom glands, often found at the base of a lancet and an inoculation system which, in many cases, consists of a set of stingers arranged on the fins, head or tail.
Relatively little is known about the venoms inoculated, but all of them contain toxins, with varying effects on human health. In moray eels, it is the saliva, rather than the venom, that is toxic. In a number of species, the venom is heat-labile, meaning that it can be destroyed by heat (50 to 60°C). When heat is applied to the affected area, it can help deactivate the venom and alleviate the pain.
Remember that the prognosis is always less favourable in individuals who have been previously sensitised to the venom in question. The seriousness of the envenomation depends in large part on the amount of venom injected.
To help you learn more about risk-inducing species on our coastlines and determine how to react in the event of an accident, an inventory of the main venomous species found along the coasts of mainland France and the overseas departments has been provided, along with the action recommended to those accompanying the accident victim or the rescue staff.