Sargassum seaweed, or “Sargasso,” has become a real issue in many of the world’s oceans. While it is vital for the survival and biodiversity of a variety of marine species such as turtles and other organisms, it is also becoming an increasing nuisance and risk to human health. Depending on its composition and density, sargassum can become deadly. This article will explore the potential harmful effects of sargassum on human health and the environment.
Sargassum seaweed is a brown pigment floating seaweed, which is native to the Sargasso Sea. It forms extensive oceanic meadows, with bloom sizes estimated to cover up to 15,000 square kilometers. The species is known to spread quickly and has recently been identified in the Atlantic, Pacific and Indian Oceans. The seaweed has been reported to grow up to 20 meters deep and pose a significant risk to coral reefs, affecting the whole marine ecosystem.
There is mounting evidence from scientific research that sargassum seaweed can be harmful to humans. The most significant health risk is posed by the toxins contained in the sargassum, which can potentially cause a range of gastrointestinal problems, skin irritation, allergic reactions and respiratory illness. Some of the toxins found in the milky-brown seaweed are potentially carcinogenic and harmful to aquatic life. The toxins can also enter the food chain when they’re consumed by fish and other marine creatures, ultimately making their way to humans and posing serious health risks.
Sargassum seaweed is also thought to produce gases which can contribute to global warming and cause oxygen depletion in the water. The seaweed can form huge constructions imprisoning and killing fishes and other organisms. These seaweed constructions can also become a navigational hazard to ships, and have even been known to sink boats. The smell of the seaweed also has a major environmental impact, as it produces a stench which takes days to dissipate.
These circumstances, however, do not always remain constant. Many believe that reducing carbon emissions and coastal contamination could slash the amount of sargassum, however it’s difficult to measure the effects of the disruption caused by human activity and hence the effects of the seaweed remains debatable.
The World Health Organisation recently released a report which confirms the potential dangerous effects of sargassum and encourages governments to adjust their response to the problem. For instance, recommendations include encouraging the public to avoid contact with affected areas and cast members to conduct regular beach clean ups, as sargassum releases harmful toxins into the water while disintegrating.
The Socio-Economic Impact
The presence of sargassum seaweed is also having a major socio-economic impact, as it is affecting tourism and recreational activities in numerous coastal regions, particularly beaches. Many reports from experts point to the risks posed by the seaweed to marine life, which could significantly impact the fishing industry.
The abundance of sargassum seaweed could lead to an economic crisis in the regions most affected by it, as local businesses would be undergoing a significant decrease in demand and revenue. Furthermore, the long-term environmental impact of sargassum could have far-reaching consequences for the entire food chain.
As debate continues to simmer around the issue, some eco-friendly initiatives are offering some relief from the swarms of seaweed. In 2018, the World Wildlife Fund launched a global project to monitor and control the spread of sargassum seaweed with the help of satellite imagery, allowing for better coordination of clean-ups and predictions of future outbreaks.
The initiative has inspired dozens of local projects in countries such as Mexico, the Dominican Republic, and Trinidad and Tobago, where residents are now looking to sargassum as a potential source of energy, fertilizer and even biodegradable plastic.
Research, Prevention and Solutions
In order to develop effective solutions for controlling the spread of sargassum seaweed, more research and an improved understanding of the global scale of the problem is needed. Some research studies have proposed the use of ionic silver, an antimicrobial agent, and other natural remedies as a potential way to repel or control the seaweed.
While large-scale management solutions are still being developed at research level, there are some simple steps being taken in the affected regions to mitigate the impact of the seaweed. For example, the use of earth-moving vehicles to collect and clean beach areas close to urban centres has been proposed, and beach rakes are also being employed in these areas to collect sargassum as it washes up on shore. In some cases, the seaweed is then repurposed for fish farms or used as a biomass fuel.
Another option is to build containment barriers at-sea, which can impede the flow of sargassum towards the shore. These containment walls would need to be reinforced over time due to the potential corrosion caused by saltwater exposure.
Efforts to Tackle the Problem at a Global Scale
The World Bank recently funded a Caribbean Sargassum Initiative to enhance the region’s ability to manage sargassum seaweed outbreaks through the use of innovative technologies and knowledge exchange.
In addition, the United Nations Environment Programme (UNEP) recently launched ‘Sargasso Sea Alliance’ initiative, a global partnership which unites the efforts of governments, universities, non-governmental organizations and the private sector to reduce the risk of sargassum seaweed accumulation.
Many coastal communities are also joining forces to tackle sargassum. For instance, the Caribbean-Sargassum Initiative has been working with local stakeholders to create multi-level programmes to monitor and control the spread of the brown seaweed.
That said, sargassum seaweed is not only a threat to the marine environment, but also a challenge to the socio-economic and legal frameworks surrounding coastal environments.
The Way Ahead
The long-term effectiveness of the solutions being proposed will depend on the ability of local governments to raise awareness and coordinate the clean-up efforts needed to control and manage sargassum seaweed. It is crucial for global stakeholders to acknowledge the importance of protecting marine ecosystems in order to keep the oceans in equilibrium.
Ultimately, a collaborative effort between all environmental actors is needed to mitigate the potential risks posed by the seaweed, while also looking for ways to repurpose and reuse it, in order to create positive environmental outcomes in the face of the existing problem.
Impacts on Marine Biodiversity
Sargassum seaweed has proven to be incredibly beneficial for a variety of species. For instance, it provides a safe place for small organisms to hide from predators, a nesting spot for sea turtles and a food source for seabirds. Despite this, the rapid accumulation of sargassum seaweed in certain areas has a detrimental effect on the marine biodiversity as the seaweed is believed to disrupt the relationship between species.
Furthermore, the seaweed’s decomposition process produces a lot of organic matter which stimulates excessive growth of microalgae and can lead to low oxygen concentrations in the water. These changes in oceanographic conditions can cause the death and extinction of some species as some are more sensitive to these changes than others.
Organisms that usually live deep in the water, such as coral reefs, are hit the hardest as they need clear, oxygen-rich water to survive. The continuous exposure of the organisms to polluted and oxygen-depleted waters reduces their ability to survive over time.
Research suggests that nitrogen-rich fertilizers and waste water runoff are the main causes of the microscopic algae blooms, also known as ‘red tides’. As nitrogen-rich nutrients fuel the growth of algae and rapidly increase sargassum’s biomass, it is likely that limiting the discharge of these pollutants will help reduce the sargassum infestations.
Conclusion
In conclusion, sargassum seaweed is presenting a major challenge to coastal communities around the world due to its potential to cause serious health risks and damage to the environment. By working together, research institutes, governments, non-governmental organizations and private sector businesses can strengthen the fight against sargassum by developing sustainable solutions and mitigating the effects of the brown seaweed.
