
Authored by Cameron Kniffen, Curator of Education for the Detroit Zoological Society (DZS).
More than 70 percent of the Earth’s surface is covered by water. As residents of Michigan, a state with beautiful, bountiful lakes and rivers, we tend to focus on freshwater systems when considering our impact on water quality, pollution and aquatic ecosystems. Many of us receive a thorough education on the vital role of the Great Lakes in our state’s history, economy and ecosystems. We are also taught to take responsibility for preserving our abundant water resources and to understand the negative effects of polluted waters on both people and the environment. It’s important to realize that our actions can impact water quality in the Great Lakes and other ecosystems outside of our freshwater sources.
Many of us unknowingly contribute to the accumulation of microplastics in our waterways. Despite their small size, microplastics possess a significant potential to impact various species and ecosystems. Microplastics are tiny, minuscule plastic particles that can infiltrate virtually any environment — including the smallest, deepest crevasses of the ocean — and exert their harmful effects. Microplastics are produced by reducing plastic into miniature versions of its original manufactured form. While some microplastics are intentionally added to soaps and scrubs that contain microbeads, others are formed through prolonged exposure to the sun and constant movement in the water, causing the plastics to degrade into tiny particles.

The accumulation of microplastics in our environment is an alarming concern due to their damaging effects on wildlife and their potential impact on human health. The ingestion of microplastics can cause physical harm to marine life. The particles can accumulate in the digestive tract, leading to blockages, ulcers and other internal injuries. This can result in severe malnutrition, starvation and even death. The presence of microplastics in marine organisms can also interfere with their feeding behavior, reproduction and growth rates.
Additionally, microplastics can have chemical and biological impacts on marine organisms. Plastic particles can contain or absorb toxic chemicals from their surroundings, such as polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals. When these microplastics are ingested, the chemicals can leach out and be released into the organisms’ tissues, potentially causing toxicity and disrupting physiological functions.

Furthermore, the potential for microplastics to enter the food chain and eventually impact human health is a growing concern. Seafood, such as fish, shellfish and mollusks, is an important source of protein and essential nutrients for many people around the world. As microplastics are ingested by marine organisms, they can bioaccumulate and pass through the food web, eventually reaching the seafood that humans consume. If these consumed organisms have ingested microplastics, there is a risk that humans may indirectly consume these particles when consuming contaminated seafood. Once ingested by humans, microplastics can potentially have adverse health effects.
Michigan’s Great Lakes area is an excellent demonstration of this interconnectedness. As plastic travels from local watersheds to the Great Lakes, it gradually breaks down into smaller fragments of plastic materials. Microplastics can effortlessly hitch a ride in the waterways in this region and flow with the natural motions from west to east. Lake Superior flows those same microplastics into Lake Huron through the St. Mary’s River, and Lake Huron then seamlessly flows into Lake Erie through the St. Clair and Detroit Rivers. Finally, Lake Erie deposits the microplastics into Lake Ontario via the Niagara River. Ultimately, the entire system and its pollutants eventually drain into the Atlantic Ocean through the St. Lawrence River.

Working collaboratively and taking a thoughtful approach to our plastic consumption can positively impact the reduction of microplastics in our water systems. It’s important to consider products with minimal packaging and express our viewpoints to local and state governments in support of stronger recycling efforts and limits on plastic usage in manufacturing. Participating in beach clean-up events can also contribute to a cleaner future. However, it’s crucial we come together as a united front and advocate for regulations on large industrial manufacturers at a national and global level. Through advocacy and voting, communities can achieve significant change. With our collective efforts, we can create a brighter and cleaner future for all.
The DZS is passionate about lessening our impact on our aquatic ecosystems. More than 10 years ago, the Detroit Zoo stopped carrying single-use plastic straws and lids and has made many more steps in the direction of a more sustainable future since then, including stopping the use of plastics bags at our gift shops and eliminating plastic bottle sales – which were previously our largest concession sale item – meant for single-use at all Detroit Zoo concessions, replacing them with reusable water bottles and water bottle refill stations. In celebration of World Oceans Day (June 8), we welcome you to join us at the Detroit Zoo and learn more about the ocean through educational programming on Saturday, June 10.