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
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).
