Fecal bacteria was found on many beaches in a study by researchers at the University of Hawaii at Manoa.
The study, published in "Environmental Science & Technology," found that fecal indicator bacteria survives longer on the sand than it does in the water.
The source of these dangerous microbes is often sewer runoff water at the beach. Fecal indicator bacteria has a faster decay in the water than it does on the sand, which is why it sticks around longer, notes CityLab.
Fecal indicator bacteria contains microbes that can make people sick in the water and on the sand.
To stay healthy, the Environmental Protection Agency (EPA) website advises beachgoers to watch for signs that say the beach is closed or warn of hazards.
People shouldn't swim at beaches where sewage pipes are seen or after a heavy rainstorm at beaches near big cities. Also, if you must go in the water, try not to stick your head under to avoid getting sick.
On the beach, try to keep a towel or some other type of material between your skin and the sand. Avoid getting buried under the sand for fun.