Backyard Talk

Our oceans are filled with plastic. Our bodies may be, too

by Kenia French, CHEJ Communications Intern 
A study from the University of Victoria found that humans likely consume 74,000-114,000 microplastic particles per year. How does this happen, and what does this mean for our health?
What are microplastics and where do they come from? 
Every year, between 5 and 14 million tons of plastic flow into our oceans, and for a long time, we believed that it just stays there. You may have heard of the Great Pacific Garbage Patch: an expanse of plastic litter larger than Texas floating in the middle of the Pacific ocean. In fact, wherever there’s a major ocean in the world, there’s also a massive garbage island sitting in the middle. 
However, recent research suggests that these large expanses of plastic don’t just simply sit there: they degrade over time. This degradation has resulted in a phenomenon referred to as microplastic, or tiny particles of plastic smaller than 5 millimeters, often microscopic. These tiny particles of plastic have infiltrated not only our oceans, but all of the water systems on our planet.
Why are these tiny plastic particles so bad for marine ecosystems? 
Microplastic pollution is particularly dangerous because it has a particle and chemical aspect. Microplastics have been found in over 114 aquatic species. Plastic particles fill fish’s stomachs and clog their organs, which has been linked to disrupted eating patterns and starvation. Filter feeders (think oysters) are particularly impacted because their feeding mechanism involves sifting tiny, microscopic organisms out of ocean water— microplastics inevitably get caught up in their dinner. 
Microplastics have the potential to leach dangerous chemicals, like PCBs or BPA. While PCBs have been banned in the US since 1979, they aren’t banned worldwide, and many find their way into the ocean through illegal dumping or countries with less stringent regulations. These chemicals have been linked to liver and reproductive damage in many fish species, and to accelerating the destruction of coral reefs. 
If microplastics are having their largest impact on marine life, how do they affect people? 
The good news is that most microplastics that affect sea animals don’t make it back to affect humans. Microplastics remain in fish gut tissue, and haven’t made it to the muscle tissue, which is what we eat. 
As the University of Victoria study found, though, it is clear that we are consuming an astounding number of microplastics from our everyday foods. Seafood is not the only vector for contamination: they found that tap water, bottled water, and sugar, are just a few sources of human microplastic consumption. 
Should we be concerned about the potential impact of microplastics on our health? 
According to the National Geographic, dosage is a key concept in toxicology. While 74,000-141,000 may seem like very large numbers, they may be quite small in terms of microplastic toxicity and may not be enough to have any impact on human health. Consuming plastic doesn’t really sound healthy, but everything is relative, and there isn’t yet any evidence linking microplastics to human health problems. 
How can I limit my impact on microplastic pollution? 
What is clear now is that plastic consumption is a problem for species that live on our planet, especially ocean species. If these plastics are harmful for our oceans, then they are probably aren’t the best thing for us to consume either. 
There are alternatives: scientists have discovered ways to create biodegradable plastics, and people can push for bans on plastics responsible for leaching toxic chemicals, like our PCB ban. Overall, the best thing for a person to do to reduce plastic pollution is to try to limit your consumption of single use plastics. Single use plastics are plastics you only use once: plastic bags, like the ones your groceries are bagged in, are the main culprit, but plastic water bottles and product packaging are significant sources as well. Next time you’re at the grocery store, choose a paper bag, or better yet— a reusable one!