The invisible harm of Microplastics

Did you know that inhalation is a significant route of microplastic exposure? Yes, plastic particles are in the very air we breathe, making it a crucial entry point for these tiny pollutants into our bodies.

Other than getting a professional-grade air filter in our homes, there is little we can do about the air outside our homes - so this article will focus mainly on microplastics in things that are WITHIN our control. 💪

In an era dominated by convenience, reducing our plastic consumption is quite the challenge. EVERYTHING is stored in plastic or wrapped in plastic - the food and beverage industry accounts for a staggering 31% of overall plastic usage [1].

While marine contamination and plastic in seafood receive considerable attention, it's important to recognize that there are other important ways plastic enters our bodies. Let’s dive in.

What Are Microplastics?

Let's start by understanding what microplastics actually are.

These are tiny plastic particles, often smaller than 5mm, and they include even tinier ones known as nanoplastics, which measure less than 0.1μm. The smaller they are, the more damage they can do, as nanoparticles can travel to major organs and even breach the blood-brain barrier – a particular concern for pregnant women, babies, and children.

Plastic Impact on Health

So, why should we be concerned about these microplastics in our bodies?

In the past, it was challenging to establish a direct link between plastic and various diseases. This was partly due to the fact that 'plastic' is a broad category that includes a mix of different toxins, such as endocrine-disrupting phthalates, BPA, and potentially carcinogenic azo dyes.

However, a recent study [2] estimated that the harmful chemicals in plastics contributed to a staggering $280 billion in healthcare costs in the USA in 2018 alone. That's a massive wake-up call!

Not All Plastic Is Made The Same

There are a few different types of plastic - and the number in the triangle on the bottom of them tells you the potential toxins you may be exposed to:

​​So, How Does Plastic Impact Our Health?

Here Are A Few Hypotheses:

• Oxidative Stress: Think of oxidative stress as rust – it leads to inflammation, age-related changes in appearance (like wrinkles and gray hair), organ function deterioration, DNA alterations, and contributes to long-term issues like diabetes and cancer. Unfortunately, all plastics except HDPE (with #2 in the triangle) have been shown to induce oxidative stress [9], leading to inflammation and neurotoxicity.
   
• Potential Carcinogen: Increased exposure to elevated microplastic levels has been associated with carcinogenic effects in animal studies, potentially contributing to lung, stomach, and esophageal cancer [7].
   
• Gut Health Disruption: Once microplastics enter the gut, they can break down and release harmful constituents and absorbed toxins [11]. Certain plastic types, like #1, 2, 4, 5, and 6, are often linked to gastrointestinal issues. Research also suggests that microplastics can alter the intestinal flora in our gut [28], causing inflammation and inducing toxic effects on the entire body, especially when particles are smaller than 150 μm [13]. Since Gut health is central to our overall health, this is a huge concern.
  
  
• Hormone Disruption: Microplastics can significantly impact reproductive health, particularly due to the chemicals they leach, such as phthalates and BPA. These substances are endocrine disruptors that mimic hormones like estrogen, affecting fertility, menstrual cycles, and hormone-sensitive tissues. Exposure to plastic nanoparticles can lead to various health issues, from premature pregnancy to infertility, lower thyroid hormone levels, placental diseases, reproductive cancers, sexual dysfunction, and hormonal imbalances [7].

Women and Hormones

Speaking of hormones, a vulnerable time when endocrine disruptor exposure is more critical is in utero development, and in babies and toddlers. An increase in phthalate levels in the womb can lead to asthma and allergies in children [27], and in men, phthalate exposure has led to lower sperm counts later in life.

Full disclosure: I was (plastic) bottled fed as a baby, and so were my kids before I learned about BPA… so I’m not coming at you from my high horse - but rather a humble place of “I also did this” and IF you have the means to choose differently, please consider it.   

Plastic milk bottles, especially those made of #5 or 7 plastic, can expose babies to up to 3 million microplastic particles per day, . 

BPA has adverse effects on children as they develop, shaping fetal brain development and postnatal behavioral problems [16]. There’s also growing evidence that despite movements for "BPA-free" products, substitutes like BPS and BPF exert similar harmful effects, so it’s better to avoid these plastics altogether.

Glass or stainless steel are better alternatives, and if you must use plastic, opt for PP bottles (#5) since they don't contain BPA. However, be cautious when microwaving these bottles, as they can still release microplastics. I'd also advise steering clear of silicone bottles for now, as there isn't enough data on their safety.

So, here's what you can do to protect your hormone health:

Avoid plastic, especially types #1, 3, and 7.

PVC (#3), present in Saran wrap (or cling film in the UK), has been shown to leach estrogen receptor agonists above safe levels [9] - don’t wrap your food in these!

Watch out for plasticizers like phthalates and BPA.

Pregnant women and babies are especially vulnerable.

Microplastics in Food

Now, let's talk about how microplastics make their way into our food. There are two primary sources of contamination:

• We ingest larger plastic particles that break off from packaging or contaminate food during manufacturing.
• Plastic degradation due to factors like heat, sunlight, or acidity accelerates the leaching of chemicals we consume from micro and nano particles.

Here are some factors that speed up this leaching process:

• Material Type: Avoid storing food in plastics with #1, 3, 6, and 7 in the triangle on the bottom, as these tend to contain more harmful chemicals.
• Temperature: Higher temperatures significantly increase the release of plastic particles. For example, leaving a plastic water bottle in a hot car or putting hot food in a plastic container can be problematic.
• Microwave Use: Microwaving is a big no-no when it comes to plastics. Containers can release millions of microplastics and billions of nanoplastics in just a few minutes. Even polypropylene infant feeding bottles have been known to release more microplastics when microwaved.
• UV Light: Sunlight exposure can weaken and fragment plastics, making them more likely to leach chemicals.
• Mechanical Force: Shaking liquids in plastic containers or squeezing plastic bottles can accelerate the breakdown of plastic.
• Cleaning Agents: Chemicals and acids used for cleaning can encourage plastic breakdown, so avoid harsh cleaning chemicals or vinegar when cleaning plastic.
• Acidic Foods: Contact with acidic foods intensifies the release of micro and nanoplastics, especially when combined with heat or microwaving [32]. So, it's best to avoid microwaving liquids, acidic foods, or fruit juices in plastic containers.

For instance, a plastic bottle of olive oil left near the stove, exposed to heat, frequent mechanical use, and potentially UV radiation, can drastically increase the leaching of chemicals. Research shows that this combined exposure could yield over 15,000 plastic particles in your food!

Should I Worry About Microplastics In Salt?

Now, let's address the panic that is microplastics in salt. If you are on social media, you’d think this was a major source of exposure…

Yes, microplastic has been found in salt worldwide, with sea salt being the highest, followed by lake salt and rock salt.

But let’s get a dose of common sense here. Calculations suggest that for the average consumer eating around 5g of salt per day, the consumption of microplastics from table salt ranges from 155 to 1571 particles per year - a DROP in the ocean compared to other sources like plastic water bottles or plastic packaged foods. So, instead of solely focusing on this, I recommend reducing your exposure through other methods mentioned in this article.

Most plastic found in salt doesn't come from the packaging itself but from marine plastic pollution and the production process, as evidenced by the different types of plastic found.

If you're looking for salt brands with minimal contamination, Only Salt is sourced from a rare spring in the Andes Mountains. Jacobsen salt is another brand that tests their salt for microplastics and lead, if you're still concerned.

Ultimately, while 90% of all table sea salts contain plastics, don't obsess over this if you don't consume a lot of salt. There are more impactful changes you can make to reduce your exposure, such as getting a water filter or an air filter, so prioritize those if they suit your lifestyle/budget.

Microplastics In Water

Now… Water IS something I would worry about. We should be drinking around 2L of water per day - but what type of water are you consuming? And is it contaminated?

Bottled water is usually stored in #1 and #2 plastic [9]. These bottles are susceptible to leaching when exposed to high temperature [29], sunlight [30], and when used repeatedly [20, 31].

On average, if you consume only bottled water, your annual microplastic intake is around 90,000 particles. However, using a reusable glass/stainless steel bottle can reduce this number to just 4000 (avoid aluminum bottles which may be lined with BPA resin, I also wouldn’t want aluminum in my water either!).

Since microplastic contamination in water is widespread, investing in a high-quality water filter for home use and carrying filtered water in stainless steel or glass containers when you go out is a smart move.

To sum it up:

• Avoid plastic bottled water, especially if heated or exposed to sunlight.
• Don't reuse plastic water bottles - these are single use. Repeated use encourages leaching.
• Consider the type of container you're using for drinking water – stainless steel or glass is best.

Water filters I like:

• Aquatru - $125 off via my affiliate link here. I like their countertop units if you are short on space.
• Under sink multi-stage filter - This is the under-sink unit I have at home. I used to use reverse osmosis, however, I didn’t like the idea of water wastage or the need to add back minerals, so I switched to this one. code platefulhealth for a discount.

What Other Foods Do We Find High Concentrations Of Microplastics In?

Seafood contamination by microplastics represents a large proportion of studies related to human consumption of microplastics to date, yet these studies only scratch the surface of the total number of microplastics humans are ingesting.

Here are some other foods that are frequently stored in plastic packaging I would prioritize getting in glass where possible:

• Nut butter
• Spices
• Vinegar
• Sauces like ketchup
• Beer (cans are lined with thin plastic)

To date, there has been little research into the impact of fermented foods on the rate of plastic breakdown and chemical leaching. However, certain bacteria can start to erode plastic after 3 months, notably those commonly known as mold, so I would avoid buying fermented food in plastic too.

Here Are 10 Simple Steps I Follow To Reduce MP Exposure:

• Buy from the farmers market or the organic section without plastic wrapping where possible. 
• Avoid ultra-processed foods - almost all these foods contain some level of phthalates, microplastic, PFAs and other contaminants.
• Get a water filter and reusable stainless steel or glass bottles.
• If you have to drink from plastic bottles (I get it, not always avoidable), store water at 24°C and below, away from sunlight. Don’t reuse PET bottles.
• If you buy food in a plastic container, transfer it to a Pyrex dish or ceramic plate for heating.
• Allow food to cool to room temperature before placing it in plastic storage containers.
• Avoid freezing/storing food in any plastic for 2 weeks or more.
• Avoid placing plastic containers in the dishwasher since they leach toxins into other dishes.
• Minimize the use of Saran wrap/cling wraps (contains PVC); try to use paper wraps or at least try to avoid contact between cling film and food (e.g., pull tight over the top of a ceramic bowl rather than let it directly touch the food).
• Ditch plastic cutting boards, especially avoiding polypropylene materials [23]. Polyethylene releases fewer MPs than polypropylene. Chopping technique also affects MP release - e.g., chopping a hard vegetable like carrots versus soft cheese. A solid wood cutting board is my favorite option.

Harness the power of innate detox organs - we cannot avoid plastics 100%! - and when I travel, go out, I eat and drink from plastic all the time. I don’t let this stress me out though. Some people with a certain genotype (GSTM1 absence) can bioaccumulate phthalates ,and may need to work a little harder than others to detoxify from them… 

Eating foods and adopting lifestyle measures like exercise and sweating can support your detox organs. (P.S.. Avoid gimmicky detox supplements or shakes - these are often CONTAMINATED with toxins like heavy metals or microplastic).

Remember, while we can't completely avoid plastics, we can take steps to minimize our exposure and optimize our body's detoxification processes. If you want to learn more about how to do this, I have a course called Detox Right, which teaches you how to harness your body's innate detox organs on a daily basis.

So, let's stay informed and take action to protect our health from these invisible threats. After all, small changes can make a big difference in the long run!

Stay healthy and informed, my friends! 💪🌱

Look for the little triangles

On the bottom of the plastic, there is usually a triangle with a number inside. Check it against the images below to find out best practices. 

References: 

[1]https://www.unep.org/interactives/beat-plastic-pollution/#:~:text=Approximately%2036%20per%20ce  nt%20of,landfills%20or%20as%20unregulated%20waste. 

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