Current Connection: Humans’ Impact on Our Seas

Due to the main theme of Oceania: The Underwater City Series being about marine conservation and a sustainable city beneath the sea, from time to time, I like to make connections between the futuristic story and our current world. In the story, our future world is one where humans have learned how to live in harmony with nature. Today, that is something some of us are striving to do, yet we still have a long way to go. So, for the last blog post for Terra Sea Merge, I will be highlighting a current issue impacting our oceans.

 

One of the largest “hidden” threats today is microplastics in the ocean. Unlike the images of the gigantic Pacific Ocean floating trash pile of plastic, microplastics are not easily seen. They range from 5mm (0.2in) at their largest to microscopic at their smallest ⁽¹⁾. Microplastics have been found all over the ocean, including at the bottom of the Mariana Trench. They have been found in the blood cells of marine animals and inside their guts. These include seafood that humans commonly eat. According to a Scientific American article, “The amount of microplastics in lakes and soils could rival the more than 15 trillion tons of particles thought to be floating in the ocean’s surface alone” ⁽¹⁾.

 

Microplastics are different than the regular plastics you can easily see floating in the ocean. There are two types of microplastics: primary and secondary. Primary microplastics are found in cosmetics, textiles, and fishing equipment and are designed to be small. Secondary microplastics come from the degradation of other larger plastics like plastic bags and water bottles. Ocean waves and radiation from the sun can cause large plastics to break down once they’ve reached the ocean ⁽²⁾.

 

One of the ways microplastics reach the ocean is through wastewater. Wastewater treatment facilities often allow the treated water back into natural systems like lakes, rivers, and the ocean. The standard procedures they use to purify the water aren’t able to remove all of the microplastics, allowing them to flow into the environment ⁽²⁾. If other chemicals are present in the ocean, some microplastics may bind to the other chemical pollutants and cause further problems for marine animals who ingest them ⁽²⁾. Due to the small size of microplastics, it makes it easy for marine animals to eat them, whether on purpose through the mistaken identity of their food or incidentally like when a whale gulps a large mouthful of plankton. Sometimes the particles of microplastic stay inside the animals and aren’t passed through their systems as a waste product. When this happens, it can kill the animal or pass on to the predator that eats the animal who originally ingested the microplastics. Another problem it tends to cause is lower reproductive numbers in fish. Some researchers have discovered that microplastics can cause damage to tissues and organs by being abrasive to organ walls ⁽¹⁾.

 

Eventually, everything works its way up the food chain. The issue of microplastics in the ocean has a direct impact on humans as microplastics have been found in both bottled and tap water, sea salt, and even beer ⁽¹⁾. In a study by Martins & Guilhermino published in Science of the Total Environment, they discovered in their research that microplastics not only lowered the reproduction of the first generation of fish exposed to it, but subsequent generations also had fewer young than the generation before it ⁽³⁾. Thus, any fish species exposed to microplastics that are commonly consumed by humans could potentially lower their reproductive rate, which lowers the availability of fish for human consumption.

 

Microplastics are literally everywhere in the ocean and they are a problem that needs a lot more research before the extent of the issue can be fully understood on an ecological level. Hopefully, one day, we can find a way to stop negatively impacting our oceans and reach a world similar to that in Terra Sea Merge.

 

 

You’ve reached the end of the final blog post for Terra Sea Merge. The posts will cease until the next (and final) Oceania novel is published. If you want updates on when the next book will be released or any news surrounding my novels, you can visit https://elizataye.com/news/.  I hope you enjoyed reading this blog post and if you have any comments, you can leave them here on my blog or email me directly at elizataye@gmail.com. As always, I love hearing from my readers.

 

 

 

Sources and Further Reading

 (1) https://www.scientificamerican.com/article/from-fish-to-humans-a-microplastic-invasion-may-be-taking-a-toll/

 (2) https://www.nationalgeographic.org/encyclopedia/microplastics/?utm_source=BibblioRCM_Row

 (3) https://www.sciencedirect.com/science/article/pii/S0048969718308088

Martins, A. & Guilhermino, L. Transgenerational effects and recovery of microplastics exposure in model populations of the freshwater cladoceran Daphnia maga Straus. Sci. Total Environ. 631-632, 421-428 (2018).