A Team of University of Victoria Scientists Tell Us How Much Microplastic We Ingest Daily

June 13, 2019 – In an article appearing in the Journal of Environmental Science and Technology, authors Kieran Cox, Garth Covernton, Hailey Davies, John Dower, Francis Juanes, and Sarah Dudas, all from the Department of Biology and the University of Victoria, in British Columbia, describe the ubiquity of microplastics and the risk exposure to humans. The article entitled, Human Consumption of Microplastics, describes how we consume microplastic particles daily in what we drink and eat with an annual consumption range of between 39,000 and 52,000 particles annually. If you add drinking water from single-use plastic water bottles, the numbers go up by an additional 90,000 particles each year.

Much of the plastic we take home from supermarkets and shopping trips each week ends up becoming the microplastic we consume. That’s because waste plastic doesn’t easily degrade. And when it finally becomes microplastic it gets into everything from our water, tap or bottled, alcohol, seafood, fruit, vegetables, grains, processed foods, and meat. Finding where microparticles are in the food chain and how much we ingest was the goal of the University of Victoria researchers who did a lot of number crunching looking at 26 different data collection research projects on the subject.

How did they come up with their estimates?

The University of Victoria researchers used U.S. dietary guidelines to come up with their estimates on the amount of microplastic particles ingested by adults and children annually. They indicated that despite a void in the data collection — research of measurable microplastic content could only be gleaned from 15% of daily caloric intake, they were able to estimate the 85% balance.

Why is there so little in the way of research on microplastics entering the food consumption chain?

The researchers noted that little has been done to measure microplastic content falling on the food we eat or being baked or processed into it. The dearth of microplastic ingestion knowledge covers breads, processed and raw meats, dairy, fruit, grains, vegetables, and processed and refined foods.

The Water Bottle Challenge

One thing the researchers could calculate was single-use plastic water bottle microplastic content noting that bottled water contained 22 times the volume of microplastic when compared to tap water. For those who drink their water from plastic bottles, and there are a lot of you, (more than 50 billion single-use plastic water bottles were consumed annually in the United States, a million consumed every minute) that amounts to, on average, an annual consumption of up to 130,000 microplastic particles. If all those who currently fancy their water in a single-use plastic bottle, if they drank water from the tap they would ingest a mere 4,000 microparticles per year.

Airborne Microplastic

Microplastic in the air is very much like other particulate matter that we get exposed to daily in urban environments. These are nanoparticle sized pollutions that floats in the air, rains down on us from time to time, and eventually lands in our homes and on the food we consume. We also inhale these nanoparticles into our lungs daily. Before the age of plastic began in the 1950s, the particulate matter in the air we would be exposed to included undissolved aerosols from vehicle tailpipes, and airborne carbon from the burning of fossil fuels for energy generation and heating. But now we have plastic pollution to contend with of the nanoscale variety, and we have no idea what this level of exposure means to the long-term health of humanity, and the rest of life on the planet.

Is Microplastic Toxic?

The health implications of microplastic ingestion are unknown. But the release of this study a week before the Canadian government announced a ban on single-use plastic by 2021, should have us all thinking about the use of plastic in our modern lifestyle and the hazardous waste problem it has created.

And if that is not enough to convince you that action is needed to deal with the potential danger of microplastic ingestion, there are many more studies including a new one from the University of Newcastle, Australia, that states we are ingesting up to five grams of plastic weekly, first from water, and secondly from seafood, particularly filter feeders like shellfish. What are five grams of plastic equivalent to? About the weight of one credit card that we ingest every week.

The Newcastle study doesn’t mention packaging as a third source of microplastics, but there are microparticles of plastic in clamshell casings, consumer packaging, and the produce and grocery bags we use each week without much thought when we go to the supermarket.

Scientists don’t know what the body’s tolerance is to microplastics. A study at King’s College, London, in 2017 theorized that the cumulative effect could be toxic because of chlorine and other trace chemicals found in these nanoparticles. The idea that some autoimmune diseases might be influenced by the accumulation of plastic in our gut over time has been theorized.

Then there is the research coming out of John Hopkins trying to make a similar link.

But as for the amount of microplastics ingested to trigger a negative health impact, there is insufficient research to prove any cause and effect.

So how do we stop microplastics from harming us?

The world has to wean itself off this 70-plus-year love affair with the stuff. The step being taken by Canada and the European Union, with both jurisdictions planning to enforce a single-use plastics ban by 2021, is a good starting point. But the residue of existing plastic in the environment and the up to 500-years it may take for single-use plastics in water bottles to break down to their chemical constituents, means we have a near-impossible task ahead of us. Our most likely solution will be biological, developing plastic-hungry bacteria to consume the microplastics and with it their raw chemical constituents. But even then the pollutants from plastic will remain in the environment for centuries to come.

As consumers, we can demand manufacturers, retailers, supermarkets, and groceries remove plastic packaging and bags as offerings, finding alternatives like bags and packaging made from biodegradable corn starch.

And we can cut out the use of one-time-use plastic water bottles entirely, not only because of the potentially harmful microparticles suspended in the fluid within them but also because they are among the most commonly seen plastic litter both on land as well as in water, the icons of the Anthropocene.