Why is Sea Foam Dangerous for Surfers?

Why Sea Foam Can Be Dangerous for Surfers (and More Than Just an Annoyance)

Seafoam, that frothy, bubbly substance that washes ashore, often looks whimsical and playful. But for surfers and those who enjoy the ocean, it can pose a hidden danger. While often harmless, under certain conditions, sea foam can become a significant health hazard and a navigational challenge. Let's dive into the science behind sea foam, its potential dangers, and its broader role in the marine environment.

Sea foam is created by the churning of seawater that contains high concentrations of dissolved organic matter, which can come from the natural environment in the form of algal blooms or from artificial sources.

When waves crash or hit the beach, depending on where you are, pieces of foam often stick to the sand. On windy days, this foam can rise from the ground and disperse. What is it? Is it dangerous to touch it or let your dog walk over it?

It's sea foam, and it's not at all the green we call the color of sea foam. It's usually white, although it can be a little dirty instead of bright white. Sometimes the color is closer to reddish brown, and these are the sea foams to watch out for. Let's look at how sea foam is formed and what effects it has on human health.

What's inside thick sea foam?

Seawater is made up of 96.5% water and 2.5% salt. That's just 99%, so what's the other 1%? A lot of things. According to the National Oceanic and Atmospheric Administration (NOAA), it's made up of "proteins, lipids, dead algae, detergents and other pollutants," as well as other organic and inorganic materials. When these particles are moved by wind and waves, they form foam. You can create the same effect by vigorously shaking seawater in a bottle.

Sea foam is created by molecules called surfactants, which are "sticky molecules that cling to the surface between water and air," according to Popular Science. This layer of fine stuff on the ocean's surface can come from natural sources, such as algae and seaweed, or from human pollution, such as fertilizers, detergents and sewage. Total!

One end of the molecule is hydrophobic (repels water). The other end is hydrophilic (attracted to water). The shape these molecules most easily form is a sphere, with the hydrophobic end facing inward and the hydrophilic end facing outward. The sphere forms bubbles (albeit imperfectly). Bubbles in large numbers form sea foam!

Think twice before you pop a sea foam.

Now, about that reddish-brown sea foam: It's usually caused by phytoplankton (also known as an algal bloom) and is a natural phenomenon. These little critters release toxins that aren't helpful to you, your dog, your bird, or anything else. Algal toxins can cause eye and ear irritation and even respiratory problems.

White foam may not be toxic, but that doesn't mean it's harmless. When weather conditions get completely out of control, ocean turbulence can produce a lot of sea foam. A lot of it. In the winter of 2020, a high tide in Washington state caused waves to reach about 25 feet (8 meters) high, creating a "churn effect" that sent sea foam up to a person's chest.

Later that spring, on the other side of the world, a massive sea foam storm struck the Netherlands, killing five experienced surfers.

Be careful at the beach!

You probably won't feel any health risks from tiny bubbles along the coast, but it's best to keep a safe distance. While most waves contain only small particles of dissolved salts and other contaminants, it can be harmful to human health.

When assessing the safety of an area of ​​sea foam, it's helpful to check the waters in question. Are concentrations of algal toxins high? Are pesticides used much in the area? These questions can help you determine if sea foam is part of a productive marine ecosystem or simply a symptom of something unusual.

How Does Sea Foam form?

Seafoam is essentially a natural phenomenon created by the agitation of seawater, particularly when it contains higher concentrations of dissolved organic matter. Moreover, this organic matter, primarily derived from decaying algae, plankton, and other marine organisms, acts as a surfactant, much like soap. Here's a breakdown of the process:

Organic Matter Accumulation:

When algae and plankton bloom and subsequently decompose, they release organic compounds into the water. These compounds, including proteins, fats, and other cellular debris, become dissolved organic carbon (DOC).

Agitation and Surfactant Action:

When waves break, strong winds churn the water, or storms stir up the ocean, the air gets mixed into the water column. The dissolved organic matter acts as a surfactant, reducing the surface tension of the water and allowing bubbles to form.

Bubble Formation and Stabilization:

The surfactants stabilize the bubbles, preventing them from immediately bursting. These bubbles accumulate and are carried ashore by waves and currents, forming the visible sea foam.

Concentration and Persistence:

The concentration and persistence of sea foam depend on factors such as the amount of organic matter in the water, the intensity of wave action, and wind conditions.

Why is Sea Foam Dangerous for Surfers?

While most sea foam is harmless, certain conditions can make it a health hazard for surfers and other ocean users:

Harmful Algal Blooms (HABs):

When sea foam is generated from a harmful algal bloom, it can concentrate toxins produced by the algae. These toxins can become airborne in the foam and cause respiratory irritation, eye irritation, and skin rashes.

Ingesting contaminated sea foam can lead to more severe health problems, including gastrointestinal issues and neurological effects. Red tides, which are a type of HAB , are notorious for producing toxins that can be concentrated in sea foam.

Sewage and Pollutants:

In areas with poor water quality, sea foam can contain concentrated levels of sewage, bacteria, and other pollutants. Exposure to this contaminated foam can lead to infections, skin irritations, and other health problems.

Reduced Visibility:

Thick sea foam can significantly reduce visibility, making it difficult for surfers to see obstacles, other surfers, or potential hazards in the water. However, it can increase the risk of collisions and accidents.

Slippery Surfaces:

Seafoam can create slippery surfaces on rocks and shorelines, increasing the risk of falls and injuries.

Sea Foam and the Shipping Industry:

Seafoam also plays a role, albeit a less direct one, in the shipping industry. Here's how:

Indicator of Environmental Conditions:

Large amounts of sea foam can indicate high levels of organic matter in the water, which can be a sign of algal blooms or pollution. This information can be valuable for monitoring water quality and assessing the potential impact on marine ecosystems.

Potential for Navigation Hazards:

While not a direct hazard like a reef or storm, exceptionally heavy foam can obscure smaller low-lying objects or alter the appearance of the water's surface.

Impact on Marine Equipment:

Although this is rare, persistent and thick sea foam could interfere with the operation of certain marine equipment, such as sensors or water intakes, in extreme cases.

Monitoring HABs:

As mentioned earlier, sea foam can concentrate toxins from harmful algal blooms. Monitoring sea foam can be part of a broader effort to track and manage HABs, which can affect shipping routes and port operations.

What to Do If You Encounter Sea Foam:

• Avoid contact with sea foam, especially if it appears discolored or smells unpleasant.
• If you come into contact with sea foam, wash your skin thoroughly with soap and water.
• Avoid surfing or swimming in areas with heavy sea foam, especially after storms or during algal blooms.
• Stay informed about local water quality advisories and warnings.
• If you experience any unusual symptoms after exposure to sea foam, seek medical attention.

Final words

Seafoam is a natural part of the ocean ecosystem, but human activities can influence its composition and potential dangers. Pollution, nutrient runoff, and climate change can all contribute to increased algal blooms and the production of potentially harmful sea foam. By understanding the science behind sea foam and its potential risks, we can take steps to protect ourselves and the marine environment.