Microplastics in a Modern Diet
Have you ever stopped to think about how nearly everything that we eat comes in a package?
The Plastic Curse
Plastic has only been around for 100 years or so. When it was first released, the Bakelite Corp. marketed it as the "material of a thousand uses." A more truthful description would have been the “material of a thousand years.”
Since then, the synthetic material has taken over the world. Microplastics, tiny pieces of plastic debris, scour the Earth's surface among the wettest, driest, and even the most remote locations. They have been found in falling snow1, among the sand of uninhabited islands2, and even in dust itself3. The tiny particles are inescapable.
The effects of consuming microplastics are still largely unknown. However, there are reasons to suspect that the compounding effects of consuming "nearly a credit card's worth of plastic per week” are not negligible.
Plastic Production
Estimated amount of plastic manufactured worldwide since 1950: 10 billion tons4 (equal to the mass of nearly 2,000 Great Pyramids of Giza)
Annual worldwide plastic production estimate: 400 million tons/year5 (equal to the mass of nearly 2,000 Statues of Liberty)
Annual worldwide plastic generated for food packaging estimate: 12.5 million tons/year6 (equal to the mass of over 2,000 Titanic-sized cruise ships)
How Microplastics Get Into our Food
The food chain
Plastic can be found in almost every single ecosystem on Earth, and humans are not the only species who consume it. The things we eat, and the things they have eaten, have also likely ingested plastic at some point. Even plants are not immune; microplastics are consumed through the uptake of nutrients from polluted soil.7
Packaging
42% of the world's production of plastic is used for packaging.8 That figure includes things like Amazon packages, toiletries, and "Happy Meals" from McDonald's. The Michigan State Center for Research on Ingredient Safety have published great reports explaining how small amounts of plastic packaging can infiltrate and contaminate the things that we eat. Basically, there are tiny fragments of plastic that come off of packaged food no matter what—it is trace toxic residue from contact, and simply cannot be avoided.
However, things like drinking water out of plastic, or putting plastic wrap in the microwave, can cause plastic particles to leech and degrade into our food—which is a much more serious risk. There are other things too though. Like when you rip open a bag of potato chips or crack a bottle of Sprite, you probably do not stop to think about the tiny pieces of plastic you can’t see.9
Cumulative Plastic Waste
Health Effects
There is still not enough scientific evidence to prove that any negative health effects are directly attributed to the consumption of plastics or their byproducts. However, in recent years, scientific investigations into the effects of microplastics on marine and freshwater ecosystems have rapidly accelerated. Also, there have been an increasing number of studies aimed at observing organic biochemical responses to microplastic exposure and ingestion within controlled laboratory settings. Most of the research available comes from studies on fish, aquatic mammals, and crustaceans. The human consequences of the persistent presence of microplastics within the food chain are predicted as such:
Microplastics passing through the blood-brain barrier
The blood-brain barrier is a semipermeable regulator of the molecules and particles that enter and exit our nervous system. Microplastics are small enough to get through the barrier and could contaminate things like blood flow, organ membranes, and negatively effect other synaptic transcriptions.1011
Slowed metabolic rate
In organisms such as mice, fish, and plankton, exposure to microplastics has reduced the catalyzation of necessary metabolic enzymes, which has resulted in the accumulation of fatty acids, lipids and a slower BMR.1213
Weakened immunity
Researchers have theorized that microplastics may serve as magnets that host harmful bacteria. As carriers of pollutants, they may release trace amounts of toxic chemicals into our blood and organs.14
Decreased reproductive rate
In male mice, exposure to microplastics decreased the total number of viable reproductive cells and increased the rate of sperm deformity. Testosterone was also reduced in comparison to a control group.
Female mice that were exposed to microplastics produced fewer viable embryos, and the overall rate of pregnancy was significantly reduced in comparison to a control group. Female mice appeared more susceptible to the negative effects.15
Reduced energy storage and enzyme activity
Short-term exposure to high concentrations of microplastics has been linked to oxidative stress, cellular dysfunction, increased inflammation, and apoptosis (cell-death). Many of these toxicological effects have been found in cell cultures that do not simulate real-life exposure.16
What Can We Do?
Avoid using plastic products
Speak out against plastic manufacturing
Introduce producer responsibility
Grow our own food
Don't heat plastic containers
Regularly dust and vacuum
Buy and store food in glass, foil, and silicone
Promote reuse