The ocean plays a major role in the survival of our planet for well-known reasons, such as the ability to slow global warming by trapping harmful carbon compounds or the ability to release vast quantities of oxygen. But if the ocean fails, our health will be affected in direct and indirect ways. Regardless of whether we live near or far from the beach, we interact with the ocean individually on a daily basis.
Most people eat a variety of seafood ranging from fish to shellfish to seaweed. For example, wakame is a popular seaweed, sometimes called a sea vegetable, used in seaweed salads; agar contains a polysaccharide used to make gelatin; and emulsifiers from seaweed are used to give foods, such as ice cream, a rich creamy texture.
We also drink water from the ocean. While the majority of our drinking water comes from the ocean through the water cycle(by natural processes of evaporation followed by condensation into our lakes, streams and other freshwater sources), people are increasingly bypassing the cycle by removing salt directly from ocean water to make drinking water. This man-made process, called desalination, is costly, but it works.
Healthy biomolecules originate in the ocean. For centuries, global cultures have used red, brown, and green seaweeds as sources of medicinal products, vitamins, and iron. The more we explore ocean organisms, the more scientists are discovering new unicellular and multicellular species that produce unique metabolites that may combat infection, cancer, and other diseases.
In other words, with a multitude of health-related resources derived from the ocean, the ocean is too big to fail. Yet it can. Various types of pollutants threaten its survival – and ours.
For example, if the ocean is destabilized due to warm temperatures, chemical runoff, or oil spills, the normal growth of seaweed can spin out of control. This growth is more commonly known as a “harmful algal bloom,” or HAB.
Why are HABs harmful? Seaweed, otherwise known as algae, in their normal growth state produce secondary metabolites. But some of these chemicals can be toxic, and when they’re released from the algae in high quantities, the toxins become hazardous to human health.
Toxins can get into seafood species, affecting the food we eat, and toxins can become airborne, causing various types of respiratory distress. Toxins can also cause marine mammals and other organisms to suffer, further destabilizing the aquatic ecosystem.
Government control of seafood consumption during HABs actually protects us from eating fish that is contaminated. Additionally, people should know not to fish on their own or swim in waters that appear sludgy from green, brown or red algae, as those are indicators of a harmful algal bloom.
The good news is that while studying harmful algal blooms, researchers funded by the National Institutes of Environmental Health Sciences, found that some of the toxins produced, when administered in smaller, specifically defined concentrations, can serve as treatments for diseases such as cystic fibrosis. This study suggests that further research on the ocean, exploring its species biodiversity and molecular heterogeneity, will result in the discovery of as-yet unknown products that support human health and reduce disease.