Plastics infiltrate marine sanctuaries, the world's most secured ocean regions.
The onslaught of microplastics continues to swamp our planet. They can be found in our tap water, soil, and even our lungs. They're at the bottom of the Mariana Trench, atop Mount Everest, and within our own bodies. Even the most protected marine areas, seemingly far removed from human interaction, are not immune to this pollution.
A recent study spearheaded by Brazilian and Australian researchers has revealed that these Areas of Integral Protection (API), the most restrictive class of Marine Protected Areas (MPAs), are contaminated by microplastics. There are approximately 16,500 marine protected areas globally, encompassing around 8.36% of the world's oceans. However, only 2.9% are under full or high protection, such as no-take zones.
To detect contamination, the team employed a unique method: bivalve molluscs, such as oysters and mussels, which filter seawater and retain contaminants like microplastics in their gills and tissues.
"By examining these molluscs," explains Italo Braga, the study's coordinator and professor at the Institute of Marine Science of the Federal University of São Paulo, "we can analyze a more reliable history of contamination, as they accumulate pollutants over time."
The research found microplastics in all 10 integral protection areas studied, with an average concentration of 0.42 ± 0.34 particles per gram of wet tissue.
Health Concerns
The chemical analysis of the microplastics revealed that 59.4% were composed mostly of alkyd polymers, cellulose, polyethylene terephthalate, and polytetrafluoroethylene. The remaining 40.6% were unknown.
"Our study shows that microplastic contamination is prevalent, even in the most protected environmental areas," Braga notes. "For instance, in Atol das Rocas, where no human activity is permitted and tourists are excluded. Microplastics can reach these remote places through wind or ocean currents."
The presence of microplastics in MPAs raises concerns, as they can be ingested by a wide range of marine organisms, from plankton to top predators, and have been linked to physiological and neurological harm.
Strategies to combat this pollution are necessary. These might include enhancing waste management systems near MPAs, reducing plastic inputs from terrestrial sources, implementing education and awareness programs to reduce plastic consumption and waste, long-term monitoring programs within MPAs assessing contamination levels and management strategies' effectiveness, and even global measures like the proposed Global Plastics Treaty coordinated by the United Nations Environment Program.
"It's not just about creating MPAs," says marine biologist and PhD student Beatriz Zachello Nunes. "They must be accompanied by efficient environmental management and strict enforcement. However, the microplastics might not be generated locally but brought in from afar by the wind or ocean currents. To address this, global measures are the only solution."
Targeted Mitigation Strategies
Addressing microplastic contamination in MPAs requires a blend of physical, biological, and policy solutions. Here are some potential strategies:
- Employ physical barriers and collection systems to capture microplastics in waterways and areas where they accumulate.
- Encourage biofilm growth in sedimentary environments and restore vegetation in coastal areas to help reduce microplastic accumulation.
- Implement policies to reduce plastic waste at the source, such as banning single-use plastics and microbeads in personal care products.
- Identify and address specific pathways through which microplastics enter MPAs, such as stormwater runoff and wastewater systems.
- Engage the public through education campaigns and collaborate with local communities to implement sustainable practices and monitor contamination levels.
- Combine MPAs with targeted plastic waste reduction measures to increase their effectiveness in reducing microplastic levels.
- Continuously monitor microplastic levels within MPAs and conduct research to better understand pollution dynamics and inform effective mitigation strategies.
- The health and wellness implications of microplastics extend beyond the environment, as they have been linked to physiological and neurological harm in various marine organisms, including plankton and top predators.
- In the realm of health and wellness, environmental science must address the issue of microplastics to ensure the prevention of neurological disorders and other medical conditions associated with their ingestion by marine life.
- Climate change poses new challenges for the management of Marine Protected Areas (MPAs), as microplastics can be transported long distances by wind or ocean currents, overwhelming even the most protected areas, such as Atol das Rocas, where no human activity is permitted.
