The effect of red tide is present along the southwest coast of Florida. As the contaminated water sweeps toward the coast of Florida , it leaves behind countless of dead fish and organisms. Because the fish die so quickly, these toxins do not have time to build up in their tissue. Fish exposed to lower concentrations, however, may accumulate these toxins in their body. The toxins can sicken people who consume the affected fish. Recently, it has been associated with the deaths of hundreds of whales, dolphins, and manatees in North American waters. Red tides drastically affect Scandinavian and Japanese fisheries, Caribbean and South Pacific reef fishes, and shell fishing along U.S. coasts.

Waves, wind, and boat propellers in high concentrations of red tide send these particles into the air which can cause problems for the people on shore, such as respiratory infections. Common symptoms that occur from red tide include irritation of the eyes, nose, and throat, tingling lips and tongue.