The Harmful Effects of Microplastics on Sea Life and Humans

Some scientists have estimated the average person might eat 5 grams of microplastics in a week—about the weight of a credit card. Microplastics—tiny plastic particles smaller than 5 millimeters—have become one of the most significant environmental challenges. These particles result from the breakdown of larger plastics or are manufactured for use in products like cosmetics and cleaning agents. Microplastics are found everywhere, from the ocean's surface to the deepest marine trenches, and their widespread presence is increasingly concerning. 

Marine organisms, from plankton to whales, are increasingly ingesting microplastics. These particles are often mistaken for food by marine animals, who consume them directly or through contaminated prey. For example, fish and shellfish, which are critical components of the marine food web, ingest microplastics during feeding. Ingestion can cause physical harm, such as internal blockages, malnutrition, and even death, as the particles interfere with normal digestion and absorption of nutrients.

Beyond immediate harm, microplastics can accumulate in the tissues of marine organisms, causing long-term changes. In certain cases, the chemicals used in plastic manufacturing—such as additives and plasticizers—can leach into the animals' bodies, leading to endocrine disruption, reproductive issues, and a weakened immune system. Additionally, these chemicals can act as carriers for harmful pollutants like pesticides, heavy metals which are absorbed by marine species and can travel up the food chain, ultimately affecting higher predators, including humans.

Humans are not immune to the risks posed by microplastics. Seafood consumption is one of the most direct routes through which these particles enter the human body. Studies have shown that microplastics are present in fish, shellfish, and even sea salt, which means that, over time, people may unknowingly ingest significant amounts of microplastic material. The long-term health implications of microplastic ingestion are still being researched, but early studies suggest potential risks such as inflammation, tissue damage, and disruption of hormonal systems.

Furthermore, microplastics can also be found in the air, drinking water, and food products, with recent studies showing traces of plastic particles in tap water and bottled water worldwide. The tiny size of microplastics allows them to enter the human body through the lungs or digestive tract, where they may cause harm in the form of oxidative stress, inflammation, and even potential links to certain cancers.

Microplastics are becoming a serious environmental problem, affecting both marine life and human health. Marine animals, from small fish to large whales, can mistake microplastics for food, leading to physical harm and toxic chemicals entering their bodies. As these particles move up the food chain, they can eventually impact humans who eat seafood.

-Sophie, 16