Hidden dangers of plastic debris, sargassum and pathogens are threat to marine biodiversity and public health, finds study

In recent years, scientists have shed light on a concerning issue that combines the presence of plastic debris, proliferation of Sargassum seaweed and the emergence of pathogens. This trifecta poses threats not only to marine biodiversity but also to human health.

Pathogens, like Vibrio bacteria, have been identified as a leading cause of fatal diseases related to marine environments. In this article, we explore the connection between plastic waste, Sargassum and potential risks they pose to public health.

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Plastic debris and sargassum: A growing concern

Microplastics are a concern. (Image via Freepik/Alexandralittlewolf)

In the last decade, Sargassum, a type of brown macroalgae, has surged in the Sargasso Sea and Great Atlantic Sargassum Belt.

Plastic waste in oceans is a growing global issue. The connection between vibrios and Sargassum is unclear, as is their potential to harm humans when colonizing plastic and Sargassum.

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Vibrio bacteria and plastic interaction

Researchers from Florida Atlantic University conducted a groundbreaking study that involved sequencing the genomes of 16 Vibrio strains found in samples from the Caribbean and Sargasso Seas.

The study found that Vibrio has a remarkable ability to adhere to microplastics. The attachment mechanism used by these microbes is similar to that employed by bacteria, highlighting their aggressive nature.

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Pathogenic potential and concerns

Study deepens environmental concerns (Image via Freepik/art_Photostudio)

The study found unique open ocean vibrios that may be new species. These vibrios have genes for both pathogens and low nutrient acquisition, adapting them to their habitat and substrates.

Testing showed that they quickly form biofilms and exhibit pathogenic traits, including zot genes linked to intestinal infections like vibrio cholerae. That suggests that they could affect the gut and surrounding organisms.

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Implications for public health

With the increase in interactions among humans, Sargassum and plastic marine debris, the microbial flora associated with these substrates could harbor opportunistic pathogens. Beached Sargassum, in particular, appears to contain significant amounts of Vibrio bacteria.

The study emphasizes the need to raise public awareness about the associated risks. Caution should be exercised when harvesting and processing Sargassum biomass till further research is conducted.

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While more research is needed to fully understand the extent of the risks, it's crucial to be mindful of the potential dangers associated with these elements.

By addressing these concerns and implementing effective measures, we can strive towards a healthier marine environment and protect ourselves from the threats posed by these harmful interactions.

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Study: “Sargasso Sea Vibrio bacteria: underexplored potential pathovars in a perturbed habitat” by Tracy J. Mincer et al, 3 May 2023, Water Research.

(DOI: 10.1016/j.watres.2023.120033)