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Dangers in ParadiseThe beach may conjure up gorgeous images of crashing waves, tan lines and afternoon siestas. But this primo vacation hotspot isn't only about fun and serenity — it's also filled with dangers that, if you're unaware of them, can wreak havoc … or at least cause bad sunburns. Live Science assesses these hazards, from deadly riptides and destructive tsunamis to venomous jellies and harmful algae blooms.
HeatstrokeSlide 2 of 21
Usually, the body cools itself off by sweating. But if the body's temperature control system is overloaded, beachgoers can get heatstroke, the Centers for Disease Control and Prevention (CDC) reports.
During heatstroke, the body's temperature rises quickly — up to 106 degrees Fahrenheit (about 59 Celsius) or higher within 10 to 15 minutes. This can damage the brain and other vital organs, according to the CDC.
Heatstroke often happens when humidity is high (sweat doesn't evaporate as rapidly in muggy weather, making it harder to cool off), the CDC said. Other risk factors include old age (65 years or older), youth (children ages 4 or younger), obesity, fever, dehydration, heart disease, sunburn and alcohol use, the CDC said.
Symptoms include high body temperature; red, hot and dry skin (that is, no sweating); rapid pulse; throbbing headache; dizziness; nausea; confusion; and unconsciousness, the CDC said. To help, get the person to a shady area, cool him or her down with cool water, and call emergency services, the CDC said.Slide 3 of 21
TsunamisSlide 4 of 21
Beaches are prime real estate for tsunamis, so it's good to be aware of an escape route in case you're sunning on the sand when disaster hits. In fact, if you hear a tsunami warning, get out of the water, stay away from beaches and evacuate to higher ground, according to the National Tsunami Hazard Mitigation Program, a U.S. government program.
Tsunamis are a series of waves that are formed by sudden displacements in the seafloor, landslides, volcanic activity or earthquakes, according to the National Oceanic and Atmospheric Administration (NOAA). The name itself is pretty literal. In Japanese, "tsu" translates to "harbor" and "nami" means "wave," NOAA said.
Since 1850, tsunamis have killed more than 420,000 people. The Sumatra tsunami was one of the deadliest in recent years, killing about 230,000 people on Dec. 26, 2004, NOAA reported.
Many coastal areas now have tsunami-warning systems that monitor for earthquake activity and the passage of tsunami waves — but these instruments still can't give exact predictions of the timing and size of tsunamis, NOAA said.Slide 5 of 21
Algal bloomsSlide 6 of 21
Who knew something so small could be so dangerous: Harmful algal blooms, also known as red tides, happen when a colony of algae grows out of control, according to NOAA. These blooms can release toxins that harm people, fish, shellfish, other marine animals and birds, NOAA said.
One of the most famous algal blooms happens almost every summer along Florida's Gulf Coast, and it usually ends up killing fish and making shellfish unsafe to eat, NOAA said. Even nontoxic algal blooms can have disastrous effects on the ecosystem. For instance, when masses of algae die and decompose, they can deplete oxygen from the water, leaving marine creatures breathless, NOAA said.
People shouldn't eat shellfish from areas affected by toxic algal blooms. In 1990, six fishermen almost died after eating steamed mussels that they had collected from an area near Cape Cod, Massachusetts, according to the Woods Hole Oceanographic Institution.
The water may not be as tempting for swimmers, but there aren't always real health concerns linked to taking a dip in waters affected by these blooms. "Although some people can experience skin irritation and burning eyes, swimming during a red tide is safe for most people," NOAA reported. "However, never swim among dead fish, because they can be associated with harmful bacteria."
NOAA added that "If you experience adverse symptoms, get out of the water and thoroughly wash off with fresh water.”Slide 7 of 21
Shark attacksSlide 8 of 21