There’s been increased public interest in the health of our oceans since the release of Netflix’s Seaspiracy, a documentary that examines the impact of commercial fishing. Many of the claims made in Seaspiracy are controversial, but the core message of the documentary is one that many experts agree is valid: Ocean health is connected to human health. Taking better care of our oceans is crucial to preventing disease, keeping our food supply safe, and enjoying the many health benefits of ocean tourism.
Oceans drive the climate of the planet and influence everything from our food supply to our air quality. Our quality of life depends on the ocean in many ways — and, unfortunately, human activity is increasingly putting our oceans at risk.
It’s well-documented that overfishing, habitat destruction, pollution, and offshore drilling are just a few human pursuits that damage marine ecosystems. What few people realize though, is that these activities come back to hurt human health.
“Throughout the U.S., there are thousands of beach and shellfish closures or advisories each year due to the presence of harmful marine organisms, chemical pollutants, or algal toxins,” reports NOAA.
One research study in 2014 identified 14 distinct natural and anthropogenic (e.g., resulting from human activity) threats that come from the ocean. Of course, tsunamis, and floods are out of our control; but, the list also includes anthropogenic microbial and macrobial hazards, chemical hazards, and anthropogenic-introduced and extractive dangers from mining and drilling. Pollution, too, has gotten bad: by some estimates, there are at least 8 million metric tons of plastic that have entered the ocean as of 2010.
Oceans can positively impact human health, too. One study looked at the benefits of “sea bathing,” mid-18th century European hospital practice of treating patients by bathing in the ocean. Today, moving to a marine environment is shown to have numerous mental health benefits.
“In the early days, many of the ‘treatments’ focused on skin complaints and intestinal issues, whereas nowadays the focus is more on mental health and well-being; and how spending time in and around marine environments can help reduce stress, anxiety, and depression-related disorders which are fast becoming the main leading causes of disability in middle to high-income countries,” wrote the experts.
Oceans drive a healthy economy and impact our quality of life, too. NOAA estimates that coastal and marine waters support over 28 million jobs in the US. Consumers spend $55 billion each year for fishery products, and coastal areas account for 85% of all tourism revenue in America.
Ocean health directly impacts our food supply. Nearly 20% of our global food supply comes from the ocean. Aquaculture is a growing industry that promises to supply food for even more people in the future.
However, recently aquaculture has come under more scrutiny as the presence of microbials in the ocean intensified. Microbial pollution is the result of heavy metals, chemicals, dyes, agriculture waste, pesticides, and other toxins that accumulate in the ocean over decades and seriously threaten marine organisms and humans.
“Despite the known harms of microbial pollution on ocean and human health, this type of pollution regularly affects surface waters worldwide, whether from untreated human waste, wastewater treatment plant effluents, sewer overflows, or from diffuse sources of pollution, such as land runoff,” reported one study. “Recently, there is increasing concern about the introduction into the environment of bacteria that are resistant to anti-microbials, alongside substances with anti-microbial properties that select for and maintain genes conferring resistance to clinically important antibiotics among human-associated bacteria.”
What does this mean for aquaculture? Fish larvae are prone to microbial infections, meaning all these pollutants may be absorbed into our food chain at a very high rate. Using conventional anti-microbials is not a solution, as human health will be put at risk of microbial antibiotic resistance.
“Seafood harvested from microbially polluted seawater can expose consumers to these harmful agents, commonly causing gastrointestinal illness, as well as life-threatening conditions. Bivalve mollusks, like mussels and oysters, are particularly risky because as filter feeders, they bioconcentrate environmental pollutants, including antibiotic-resistant bacteria in their tissues,” concluded the study.
Aquaculture can only be a sustainable solution if operators are able to protect fish populations from toxic bacteria in the water. One solution that has been floated (pun intended) is to locate aquaculture installations further offshore. Open-ocean aquaculture benefits from stronger surface currents and sub currents, as well as deeper waters that can dilute and wash away waste and pollution.
[Read more: How Ocean Buoys Play a Role in Better Aquaculture]
Protecting our oceans starts with changing our behavior on land. Research has shown that 77% of pollutants in coastal waters come from land-based sources. We can reduce runoff, lower pollution, and protect coastal environments through better waste management, recycling, and microbial management. Lowering our reliance on plastic is also a crucial step toward improving the health of the ocean.
Organizations are also seeking to increase “blue tourism,” a form of sustainable travel that emphasizes learning about the ocean and while visiting it. For instance, projects like Aqualink’s effort to monitor ocean climate change and coral bleaching can coordinate with tourism companies taking divers to the Great Barrier Reef.
NOAA is also developing early warning systems to predict harmful algal blooms and alert coastal communities when beaches are contaminated. Not only will these models track ocean water temperatures, but also currents, wave height, and wind. More data from sources like ocean buoys can help increase the effectiveness of these forecasts and prevent people from becoming ill from contaminated seafood.
Human health depends on the health of our oceans. Not only can we avoid diseases and bacteria, but healthy oceans can help improve our food supply and can actually improve health in many ways. As climate change worsens, protecting our oceans is an important way to protect the overall planet for future generations.