How to Dramatically Reduce Your Exposure to Microplastics

Introduction

We have all heard the scare stories about microplastic exposure. It has been said that we eat up to a credit card’s worth of plastic per week. The health effects are said to be at best uncertain and at worst all kinds of harm including but not limited to, endocrine disrupting chemicals leaching into our bodies.

What surprises me is that although I have seen tons of scary stories, I have not seen any real practical advice on what to do. As a career scientist and problem, solver, I thought it would be worth examining the facts and giving people a course of action.

Exposure

Human exposure to microplastics has been measured in detail across many studies spanning decades. Although people talk a lot about exposure from beverage bottles, it turns out that air is by far the largest contribution and those particles come from textiles and rubber (not actually plastic) from car tires.

Nur Hazimah Mohamed Nor et al., Lifetime Accumulation of Microplastic in Children and Adults, Environ. Sci. Technol., 55, 8, 5084–5096, 2021

The good news is that the scientists found exposure to be very low and, in their words "insignificant". Of all the dust we ingest, plastic is just 0.001% of it. Why are people concerned over a tiny fraction and not the other 99.999%?

One might wonder what the long-term exposure adds up to over a lifetime.

That too can be calculated...

We ingest 0.0000014g per week and there are ~3600 weeks in 70 years.

So, total lifetime exposure to microplastic by ingestion is 0.005g.

The vast majority (~99.7%) of small particles ingested pass right through us.

So, we can calculate the total amount not expelled over 70 years as 0.000015g.

We also know that even those tiny amounts not expelled are attacked, degraded and removed by the body.

Risk Evaluation

We have looked at exposure and mitigation strategies, so now it is time to evaluate the level of risk. After all, we encounter thousands of risks every day and we don’t have the time or energy to get worked up about them all. We need to prioritize and worry about the main risks. The alternative is to stay at home and hide under the covers all day.

The assumption is that microplastics is a new topic, so the science has not been done yet. While it is true that the term microplastic was invented relatively recently, safety testing on plastic particles has been going on for decades, so the results are in.

A scientific review of many microplastic studies found that the consensus is that there is no evidence of harm from microplastics. That is surprising given that we see news headlines about risks all the time. Well, the study looked at that too. They found that while the majority of scientific studies find no risk, the media stories say there is a risk over 90% of the time. This means that the media have intentionally misled us, presumably because scary stories make money.

C. V?lker, J. Kramm and M. Wagner, On the Creation of Risk: Framing of Microplastics Risks in Science and Media, Global Challenges, 4 (6), 1900010, 2020

So, if most studies find no real evidence of harm, what about the minority that do claim to have identified a threat? Scientists looked into that too and found that most or all of those studies are not valid. Why not? The studies were not conducted properly.

Many studies used up to 10 million times too much plastic. Using massively more than is in the environment invalidates the study because toxicity depends on dose. Even oxygen, sugar and the safest substances are toxic if you use an unrealistically high dose. In fact, looking at eight studies they all use absurdly high concentrations of plastic and were criticized by other, more professional scientists (Lenz, Enders and Nielsen). They plotted actual levels of microplastic in the environment (red dots), which are extremely low and then compared to the concentrations of microplastic used in studies (colored lines), which are so high as to render the studies meaningless. Note that the scales are logarithmic, and a concentration of 1x106 particles per liter used in studies is a 1 000 000 000 times more than 1x10-3 particles per liter found in the environment.

R. Lenz, K. Enders, and T. G. Nielsen, Microplastic exposure studies should be environmentally realistic, Proceedings of the National Academy of Sciences, 113 (29), E4121–E4122, 2016

Not only that but only 10% of studies were done on the right kind of plastic, meaning the kinds that we actually use and that end up in the environment. The studies claiming to show a potential problem are meaningless because they were done on a special kind of lab synthesized particles that no-one in the world is actually exposed to.

Those are not the only mistakes made. Proper scientific studies use a “control” meaning that you compare the results to a suitable reference. Microplastic studies almost never compare the results for plastic particles to the results for other kinds of particle. Are there any studies where they compare plastic particles to other particles? Yes, there are, and they found plastic particles to be as toxic as clay (from soil) and cellulose, which is to say not toxic. Here is a quote from one such study:

“…the experimental design of most studies does not allow distinguishing plastic-specific effects from those caused by any other particles, such as clay and cellulose, which are ubiquitously present in the environment. We suggest that microplastic effects reported in recent ecotoxicological studies are similar to those induced by the natural particles.”

After reading hundreds of studies on plastic particles, I have yet to see a single valid study showing harm. There are decades of studies on plastic particles and here are some, all showing no reason for concern. The US FDA agrees.

V. Stock et al., Uptake and cellular effects of PE, PP, PET and PVC microplastic particles, Toxicology in Vitro, 70, 105021, 2021

J. A. Merski et al., Oral Toxicity and Bacterial Mutagenicity Studies with a Spunbond Polyethylene and Polyethylene Terephthalate Polymer Fabric, International Journal of Toxicology, 27, pp 387–395, 2008

J. A. Styles & J. Wilson, Comparison between in vitro toxicity of polymer and mineral dusts and their fibrogenicity, Ann. Occup. Hyg., Nov, 16(3), pp 241-250, 1973

Can particles be dangerous? Yes, without a doubt. Hundreds of thousands of people die every year from particles but ask yourself this. Should we be more concerned about 1 non-toxic plastic particle or the other 99999 other particles we ingest that contain real toxins and cancer-causing substances like cadmium, arsenic, lead and quartz? Every person is free to choose what to worry about, but as a scientist, I choose to worry about real, proven threats, not imaginary, disproven ones.

Conclusions

Humans are notoriously bad at judging risks. We tend to go with our gut feeling or scary headlines we see because the vast majority of us hasn’t got the time or expertise to check the science. I have checked the science, for myself and my family and I am sharing it for free, so that people can make smart choices. I hope that you now feel armed with the information you need to decide what action, if any, you want to take.

Remember that when you see scary stories about plastic particles, they come from two main sources, so-called environmental groups who want to scare us into donating our money and the media who publish sensational nonsense to get advertising dollars.

Is that too harsh a judgement? Recall that the WWF told us that we eat up to a credit card of plastic per week? Well, that was based on a study they paid for (Cox et al.) and a later, independent study (below) showed that it was utter nonsense. In fact, we do not ingest 5g per week but 0.000004g a week, which means that it would take over ten thousand years to eat a credit card of plastic. Why were the WWF so wrong? Why did they not publish a retraction when their claim was disproven? Why did the media cover the untrue scary story but not cover the good news that exposure is actually so low? Money, that’s why.

Nur Hazimah Mohamed Nor et al., Lifetime Accumulation of Microplastic in Children and Adults, Environ. Sci. Technol., 55, 8, 5084–5096, 2021

Let’s stop being manipulated by organizations greedy for our money and stop worrying needlessly over matters not deserving of our time and attention. After all, there are plenty of real dangers that deserve our attention. If you need the facts about microplastics or a keynote talk on microplastics, then contact Dr. Chris DeArmitt.

Author

Dr. Chris DeArmitt is considered a leading independent expert on the environmental effects of plastics on the environment. He read over 4000 studies unpaid and then shared the science for free via his book The Plastics Paradox, websites, podcasts, radio and TV. He is an award-winning keynote speaker educating global audiences on plastic materials science and the environmental effects of plastics.

In 2018, Chris was featured on CBS’s 60 Minutes with Scott Pelley as an expert witness in a class-action lawsuit related to Marlex mesh plastic implants. He helped thousands of women get settlements. Later television appearances include Sky News and the BBC as well as assorted radio and internet media interviews.

In 2020, Dr. DeArmitt published The Plastics Paradox, the first comprehensive, scientific overview of plastics materials and the environment covering all topics including waste, litter, microplastics, degradation, ocean plastics and more.

Chris has a multitude of granted patents as well as numerous articles, book chapters, encyclopedia chapters, and conference presentations to his name.