According to the Florida Department of Health (DOH), the Sargassum itself is not harmful to the skin, but tiny sea creatures that live in Sargassum can cause skin rashes and blisters. As Sargassum decomposes, it also gives off a substance called hydrogen sulfide. Hydrogen sulfide has a very unpleasant odor that resembles rotten eggs, and this can irritate the eyes, nose, and throat. If you have asthma or other breathing illnesses, you may be more sensitive to these symptoms. However, the levels of hydrogen sulfide in an area like the beach, with large amounts of airflow, are not expected to be harmful.
To protect yourself and your family from exposure to Sargassum, DOH advises the following:
- Always supervise children at the beach.
- Avoid touching or swimming near seaweed to avoid stinging by organisms that live in it.
- Use gloves if you must handle seaweed.
- Stay away from the beach if you experience irritation or breathing problems from hydrogen sulfide—at least until symptoms go away.
- Close windows and doors if you live near the beach.
- Avoid or limit your time on the beach if you have asthma or other respiratory problems.
We are monitoring evolving literature on the relationship between Sargassum and Vibrio vulnificus bacteria, including a recent study that suggests that this bacteria can “stick” to microplastics which increasingly live in our oceans and can become lodged in patches of Sargassum. According to the Florida Department of Health, people can get infected with Vibrio vulnificus when they eat raw shellfish, particularly oysters. The bacterium is frequently isolated from oysters and other shellfish in warm coastal waters during the summer months. Since it is naturally found in warm marine waters, people with open wounds can be exposed to Vibrio vulnificus through direct contact with seawater.
To reduce your chance of getting a Vibrio wound infection, DOH recommends the following:
- Water and wounds do not mix. Do not enter the water if you have fresh cuts or scrapes.
- Individuals who are immunocompromised, e.g. chronic liver disease, kidney disease, or weakened immune system, should wear proper foot protection to prevent cuts and injury caused by rocks and shells on the beach.