Microplastics Threaten Marine Ecosystems

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Microplastics, defined as plastic particles measuring less than five millimetres in diameter, have emerged as one of the most pervasive and troubling forms of environmental contamination confronting marine ecosystems in the twenty-first century. These particles originate from a wide variety of sources, including the gradual physical and ultraviolet degradation of larger plastic debris, the shedding of synthetic textile fibres during domestic laundering, the erosion of rubber tyres on road surfaces, and the deliberate manufacture of microbeads incorporated into personal care products. Once they enter waterways and ultimately the ocean, microplastics are extraordinarily difficult to remove due to their minute size and their tendency to disperse across enormous volumes of water and accumulate within marine sediments. Marine organisms at every trophic level, from microscopic zooplankton to filter-feeding whales, ingest these particles either directly or through the consumption of contaminated prey, with documented consequences including physical intestinal blockages, reduced feeding behaviour, hormonal disruption caused by associated chemical pollutants, and diminished reproductive success. Furthermore, because microplastics act as vectors for persistent organic pollutants and heavy metals, their presence in seafood consumed by humans raises legitimate concerns about long-term public health impacts that scientists are only beginning to systematically investigate and quantify.