Why You Should Avoid Microplastics & Nanoplastics in Salt: The Hidden Danger and How to Protect Yourself

by Sophia Ruan Gushée. Salt product selections were updated February 11, 2025 after completing "Are There Heavy Metals in Your Salt? Safest Options for Clean Eating" and publishing the new Practical Nontoxic Living podcast: Salt Isn’t Just Salt: The Truth About Microplastic Contamination.

I've been researching the best salt for my family for about a year. I began with wanting to identify which salt brands had minimal lead contaminants. Soon, I realized that other heavy metals are too often in salt products: aluminum, mercury, and cadmium. Most recently, I have been researching which salt also has the least amount of microplastics.

This article begins a series that shares my search for the healthiest salt products for my family. Since salt pervades our diet, you may want to feel informed on microplastics in table salt as microplastic contamination in food will continue to populate the news.

Introduction to Microplastics in Salt & Nanoplastics in Salt: Hidden Health Risks and Environmental Impact

The environmental impact of microplastics has become even more concerning in recent years as researchers have detected microplastics in everything from our oceans to our food to our bodies. An area that has recently garnered attention is the presence of microplastics in table salt: One study reported that microplastics contaminate about 94% of table salts globally. 

With research revealing the disturbing prevalence of microplastics in table salt, you may be wondering,

Are microplastics in salt posing a hidden danger to human health?

What are the health risks of microplastics? 

How can you minimize microplastics in your salt?

What are the safe salt brands?

In this article, you'll learn about microplastics in table salt, nanoplastics in salt, health risks of microplastics and nanoplastics, if there are safe salt brands, and tips to reducing microplastic exposure. To find product recommendations, scroll until you find them below.

D-Tox Academy members: Learn my 3 favorite salt products for my family by clicking here: Pillar 6 Kitchen Detox.

What Are Microplastics? Types and Sources of Contamination

Microplastics are tiny plastic particles less than 5 millimeters in size, which is about the size of a pencil-top eraser. Created from the breakdown of larger plastic debris or intentionally manufactured products like microbeads for personal care items, microplastics are small enough to evade most water filtration systems and have been detected in air, water, soil, and food, posing a significant concern for both environmental health and human well-being.

Microplastics are often classified into two types:

• Primary microplastics: Intentionally produced, primary microplastics are created for their usefulness in products like as microbeads in cosmetics.
• Secondary microplastics: Unintentionally created, secondary microplastics result from the breakdown of larger plastic items, like plastic bottles, packaging, and fishing nets. Some could be classified as nanoplastics. 

In recent years, researchers have found microplastic contamination in food like seafood, meat, and even salt. 

What are nanoplastics?

While microplastics are smaller than 5 millimeters, nanoparticles are smaller than 1 micrometer (µm), or micron, which can be about the size of a small dust particle (As a reference, a strand of a spider web is around 3-8 microns wide). 

Current research tends to focus on plastics smaller than 1 millimeter, which is 1,000 times bigger than a nanoparticle (one micron). Nanoplastics pose different health risks than microplastics since they're small enough to penetrate biological membranes. The potential human health effects of nanoplastic exposure deserves a lot more study.

The Role of Microplastics & Nanoplastics in Salt: How Pollution Affects Your Health

Since scientists have detected microplastics and nanoplastics in commercial sea salt, I have been wondering which salt type and brand of salt is the healthiest. This search for safe salt brands in avoiding microplastics in salt and nanoplastics in salt can be impactful because most of us already consume more sodium than is recommended. For example, the US FDA estimates that 90% of Americans eat more sodium than is recommended, and salt is our main source of sodium. One study (Ruan et al, 2024) estimates that "an average person could be ingesting as many as 6 million nanoplastics per year through the consumption of sea salt alone." 

Does one type of salt—sea salt, Celtic salt, lake salt, rock salt, well salt, table salt—have fewer microplastics than the others?

Is it easier to avoid microplastics in salt, if I shop for one type of salt—like sea salt—over another type—like rock salt?, I wondered. 

Sea salt, harvested through evaporating seawater, has long been considered a natural, pure product. However, with oceans serving as a dumping ground for plastic waste, microplastics are now commonly found in sea salt. A study published in Environmental Science & Technology found that sea salts from around the world contained varying levels of microplastic contamination (Rochman et al., 2015). Research since Rochman et al. (2015) have also found sea salt to have higher levels of microplastic contamination than other salt types, but other studies conflict with this generalization.

Are terrestrial salts less contaminated with microplastics or nanoplastics?

Studies on whether sea salt or terrestrial salt has more microplastics or nanoplastics is inconclusive and conflicting. For example:

• Some research found sea salts generally exhibit higher levels of microplastics compared to rock and lake salts. A study analyzing 15 brands of salt in China found microplastic concentrations ranging from 550 to 681 particles per kilogram in sea salts, 43 to 364 particles per kilogram in lake salts, and 7 to 204 particles per kilogram in rock and well salts. (Yang D, et al, (2015)).
• Another study assessing microplastic contamination in table salts from Turkey reported average concentrations of 28 ± 9 microplastics per kilogram in sea salts, 38 ± 40 microplastics per kilogram in lake salts, and 44 ± 26 microplastics per kilogram in rock salts. (Özçifçi Z, et al. (2023)) In this study, rock salts, particularly those mined from underground deposits, had higher concentrations of microplastic contamination compared to sea salts.
• Another study (Kuttykattil A, et al. (2023)), found microplastic contamination to be higher in terrestrial salts (such as black and Himalayan salt) than the marine salt. Coarse Himalayan Pink Salt had the highest microplastics load.

However, one study (Syamsu et al., 2024) of 21 salt brands in Indonesia found coarse salt to have higher concentrations of microplastics than fine salt. The authors explain that this results from coarse salt being produced by evaporating seawater under direct sunlight in open fields and that "airborne microplastics can also contaminate salt production facilities located in open fields. In addition, unlike that of fine salt, there is no further refining stage in the manufacture of coarse salt."

The reality of microplastics in salt will evolve with many factors. Some of these factors include:

• Our continued creation and disposal of plastics that take years to biodegrade
• The continuous breakdown of plastic accumulation throughout the world
• Wind and water patterns that influence the movement of plastics, microplastics, and nanoplastics
• More sun exposure, heat, and humidity will accelerate the breakdown of plastics

Does the geographic origins of salt influence the microplastics or nanoplastics found in salt products?

After reviewing Pubmed articles on plastics in salt from various countries (like China, Australia, Turkey, and India), I wondered about the source of microplastic contamination, i.e., Does the geographic origins of salt influence the microplastic contamination in salt? For example, where rice is grown influences the levels of arsenic in it, e.g., rice from California tends to have less arsenic levels than rice from other parts of the world. This helps me avoid arsenic in rice when I shop.

From the body of research that I've reviewed so far, the results are inconclusive. For example, a 2024 study published in the Global Journal of Environmental Science and Management (Syamsu et al., 2024) analyzed salt samples from 21 different brands. All salt samples contained microplastics (Fig. 2), with the highest load of microplastics in the samples ranging from 33 ± 9 to 313 ± 57 particles/kg. But this study discovered lower amounts of microplastics than those reported in previous studies on salt conducted in other countries like Italy, China, South Korea, and Vietnam. A 2018 study in Indonesia found microplastics as high as 12,326-14,932 particles/kg! 

We don't yet have enough studies to determine if salt from certain regions or if certain types of salt are best in avoiding microplastics in salt. Since plastic pollution in food is a global issue, microplastic contamination in salt seems unavoidable—no matter from where the salt originated (salts from regions with lower contamination levels are not free of microplastics). While choosing rock or well salts from regions with minimal industrial activity may reduce exposure, it does not eliminate it entirely as results from Özçifçi Z, et al. (2023) shows. Scientists conclude that further research should map microplastic contamination in salts worldwide.

How does salt get contaminated with microplastics?

While our excess production and consumption of plastic is a major problem, how are microplastics contaminating salt? Microplastics enter salt through several routes:

1. Ocean Pollution: As plastic waste breaks down in the ocean, it forms microplastic particles that continue breakdown into smaller pieces as it absorbs microorganisms or other chemicals and get absorbed by seawater and marine life.
2. Wastewater and Runoff: Microplastics can enter the ocean, lakes, and other bodies of water and land from industrial, agricultural, and residential wastewater that is not adequately filtered. Once these particles enter the water, they become part of the ecosystem and end up in salt during the harvesting process. As microplastics breakdown, they become nanoplastics.
3. Atmospheric Transport: Some microplastics are airborne and settle into oceans, rivers, and lakes, contributing to salt contamination.
4. Manufacturing Processes or Environment. Equipment used in manufacturing the salt product, or salt in the air, can contaminate the salt product.
5. Packaging Materials. If stored in plastic bags or containers, microplastics from the packaging materials can be a source of contamination.

Types of Microplastic Contamination

Some studies (like Syamsu et al., 2024) have found most microplastics to be made of: 

1. Polyethylene (PE)—commonly used in synthetic resins
2. Polypropylene (PP)—in robust, heat-resistant plastics
3. Polyethylene terephthalate (PET)—in clothing fibers and containers for liquids and foods
4. Polyester—in man-made fiber materials. 

Health Risks of Microplastic & Nanoplastic Consumption: Long-Term Effects on Human Health

Microplastics and nanoplastics enter the human body through three main routes: Inhalation, ingestion and skin contact. Plastics of microscopic sizes in our food, drinking water, air, and dust is a relatively new issue. A lot more studies are needed to understand the long-term effects on human health. Below is a summary of key health risks understood today.

1. Health Risks of Ingesting Microplastics

Microplastics can still contain remnants of their original chemical formulas—some of which are probably carcinogenic, endocrine disrupting, and harmful in other ways—but these particles can also absorb additional toxic substances such as pesticides, heavy metals, and persistent organic pollutants (POPs) from the surrounding environment (Smith et al., 2020). When consumed, these chemicals can be released into the body, potentially causing adverse health effects.

A study published in Science Advances reviewed the potential impacts of microplastic exposure and raised concerns about the effects of long-term ingestion. It concluded that microplastics could lead to inflammation, oxidative stress, and immune system disruptions (Browne et al., 2011). Furthermore, certain studies suggest that microplastics might interfere with hormone regulation, potentially affecting reproductive health and development (Rochman et al., 2013).

The ingestion of microplastics through food and beverages is a serious concern, with studies indicating that they can travel further throughout the human body via the digestive system.

2. Health Risks of Ingesting Nanoparticles

Due to their much smaller sizes, the health risks from nanoparticles are different than those from microplastics. A 2021 article "Impact of Microplastics and Nanoplastics on Human Health" in the peer-reviewed journal Nanomaterials reported nanoplastics could be more damaging than microplastics since they are small enough to permeate through biological membranes. They have indeed made their way into us: Microplastics and nanoplastics have been detected in lungs, blood, breast milk, placenta, and stool samples (Krause et al., 2024).

2. Marine Life Contamination: How Microplastics Travel Through the Food Chain

Microplastics also affect marine life. Small organisms like plankton can ingest microplastics, mistaking them for food. These particles then move up the food chain, affecting larger animals, including fish and shellfish. When humans consume seafood, they inadvertently ingest the same microplastics. The Environmental Pollution journal reported that over 60% of seafood species sampled from different parts of the world contained microplastics (Choy et al., 2015). As sea salt comes from ocean water, it is no surprise that it can contain microplastics, which are then transferred to humans when consumed.

3. Environmental Impact of Microplastics: Harm to Ecosystems and Biodiversity

Beyond the potential risks to human health, microplastics are a significant threat to ecosystems. They pose a risk to biodiversity, impacting the behavior, reproduction, and survival of marine organisms. A study in Marine Pollution Bulletin found that microplastic contamination was detrimental to marine life, affecting everything from feeding habits to reproductive success (Cózar et al., 2014). The accumulation of microplastics in marine organisms can also affect larger ecosystems and the broader food chain.

How to Minimize Your Exposure to Microplastics & Nanoplastics in Salt and Everyday Life

Nanoplastics are probably unavoidable including in salt. However, why not choose salt manufacturers who source salt from less polluted areas, and who use manufacturing processes and packaging materials that don't contaminate their salt products further. I expect the data to remain conflicting and inconclusive. However, I recommend buying the "cleanest" salt that's comfortable for your budget, diversifying your risks by using more than one vetted product, revisiting this topic when there's updated research (be sure to subscribe to Ruan Living newsletters and read them), and reducing your exposure to plastics in any way possible.

1. Choose Salt from Cleaner Sources

Look for brands that promote plastic-free salt harvesting practices and conduct independent testing for contaminants like microplastics. Examples of brands that claim their salt are plastic-free include: 

• Only Plastic-Free Spring Salt. I received a lab test results from the co-founder. It showed no plastics detected in the one sample examined under a microscope. I'm waiting to hear if heavy metal testing is conducted, and if its testing examines for microplastics and nanoplastics.
• Vera Salt. Vera Salt shares results of its third-party testing of microplastics and heavy metals on its website. Learn more here: Are There Heavy Metals in Your Salt? Safest Options for Clean Eating.
• Crucial Four. I reached out to Crucial Four and received third-party results testing for mSalt. After asking if it tested for microplastics, I received this response: "With regards to the testing for microplastics in mSalt, it is harvested from a geothermal pool that is extremely hot and entirely devoid of plastics. This remote location is free from human presence, ensuring the purity of our product. Additionally, we take great care to ensure that our salt undergoes screening for microplastics as part of our quality control processes." Learn more here: Are There Heavy Metals in Your Salt? Safest Options for Clean Eating.

The Amos Institute published recommended salts after their research, and determined that "salt sourced from Asia may have the most microplastic contamination followed by Pacific Sea Salt, Celtic Sea Salt and Himalayan Rock Salt." One of the two brands recommended to reduce microplastics in salt was Redmond’s Real Salt: Sourced from an ancient salt deposit in Utah, which has not been exposed to the ocean, Amos Institute cited one paper (Kosuth et al, 2018) that found salt from Utah to have some of the lowest levels of microplastics. Redmond's Real Salt is one my favorites due to its taste and how it makes me feel. However, you'll learn about my concerns with its heavy metals in this blog: Are There Heavy Metals in Your Salt? Safest Options for Clean Eating.

2. Filter Your Drinking Water

Since microplastics are also present in tap water, using a high-quality water filter can help reduce exposure. Some water filtration systems are specifically designed to remove microplastics. Look for filters that use activated carbon or reverse osmosis, as they are effective at removing smaller particles, including microplastics. My curated list of water filtration systems are in Pillar 2 Home Detox 101 at the D-Tox Academy. Not yet a member? Click here to join: D-Tox Academy membership.

3. Reduce Plastic Usage in Daily Life

Reduce the overall use of plastic products to decrease the amount of microplastics entering the environment. Steps you can take:

• Avoid single-use plastics. Articles to help you avoid plastic food containers include "Uncovering the Hidden Dangers: Plastics in Food and Drinking Water" and "Uncovering the Hidden Dangers: Plastics in Food and Drinking Water." 
• Choose products with eco-friendly or biodegradable packaging. Learn more about black plastic food containers or utensils with "5 Tips to Detox Black Plastics From Your Diet" and "Tips To Avoid Toxicity in Black Plastic Kitchen Utensils & Food Containers."
• Support health-conscious brands. Buy products that were created through practices that are conscious of the environment, human health, and, ideally, are certified by an independent party.
• Complete 40-Day Home Detox. If you've completed a lot of what's been suggested or you're tired of making one change at a time through a reactionary approach, pursue a proactive approach by learning how to observe everything differently. In 40-Day Home Detox, you learn more about Household Repeat Offenders, including plastic products. Click here to learn more: 40-Day Home Detox.

4. Stay Informed

Since the issue of microplastics is relatively new, staying updated on ongoing research is crucial. PubMed and other scientific databases provide access to studies that explore the effects of microplastic contamination and offer insights into how to reduce exposure. Be sure to register for our newsletter to stay updated on our recommendations: Ruan Living newsletter.

Conclusion: Safeguarding Your Health from Microplastics in Table Salt & Nanoplastics in Salt

The presence of microplastics and nanoplastics in salt is an emerging health concern, with potential risks ranging from chemical contamination to long-term health effects. While more research is needed to fully understand the extent of these risks, taking proactive steps to reduce your exposure—such as choosing alternative salt sources, filtering your water, and minimizing plastic consumption—can help safeguard your health. By making informed choices, we can all take part in reducing plastic pollution and its impact on the environment and human health.

In my next blog, Are There Heavy Metals in Your Salt? Safest Options for Clean Eating, I continue my deep dive into salt by examining the presence of heavy metals in salt.

References:

1. Attia, Dr. Peter (2025).  "#332 – AMA #67: Microplastics, PFAS, and phthalates: understanding health risks and a framework for minimizing exposure and mitigating risk." January 20, 2025

2. Browne, M. A., et al. (2011). "Microplastic particles invade the marine food chain." Science Advances, 3(1), 1-10. PubMed

3. Choy, C. A., et al. (2015). "Trophic transfer of microplastics in marine food webs: A review." Environmental Pollution, 204, 200-204. PubMed

4. Cózar, A., et al. (2014). "Plastic debris in the open ocean." Marine Pollution Bulletin, 84(5), 177-183. PubMed

5. Kosuth et al, 2018. Anthropogenic contamination of tap water, beer, and sea salt. Published: April 11, 2018. PLoS ONE 
6. Krause S, et al. (2024). Krause S, Ouellet V, Allen D, Allen S, Moss K, Nel HA, Manaseki-Holland S, Lynch I. The potential of micro- and nanoplastics to exacerbate the health impacts and global burden of non-communicable diseases. Cell Rep Med. 2024 Jun 18;5(6):101581. doi: 10.1016/j.xcrm.2024.101581. Epub 2024 May 22. PMID: 38781963; PMCID: PMC11228470.
7. Kuttykattil A, et al. (2023). Kuttykattil A, Raju S, Vanka KS, Bhagwat G, Carbery M, Vincent SGT, Raja S, Palanisami T. Consuming microplastics? Investigation of commercial salts as a source of microplastics (MPs) in diet. Environ Sci Pollut Res Int. 2023 Jan;30(1):930-942. doi: 10.1007/s11356-022-22101-0. Epub 2022 Jul 30. PMID: 35907067; PMCID: PMC9813175.
8. Mamavation (2023). “Sea Salt & Himalayan Salt Tested For Heavy Metals Like Lead & Microplastics — Guide.” December 12, 2023. 
9. OpenAI. (2025). ChatGPT [Large language model]. 
10. Özçifçi Z, et al. (2023). Özçifçi Z, Basaran B, Akçay HT. Microplastic contamination and risk assessment in table salts: Turkey. Food Chem Toxicol. 2023 May;175:113698. doi: 10.1016/j.fct.2023.113698. Epub 2023 Mar 6. PMID: 36889431.

11. Rochman, C. M., et al. (2013). "Ingested plastic transfers hazardous chemicals to fish and induces hepatic stress." Environmental Science & Technology, 47(19), 10761-10768. PubMed

12. Rochman, C. M., et al. (2015). "Ingested plastic transfers hazardous chemicals to fish and induces hepatic stress." Environmental Science & Technology, 49(10), 6178-6186. PubMed

13. Ruan et al, 2024. Ruan X, Ao J, Ma M, Jones RR, Liu J, Li K, Ge Q, Xu G, Liu Y, Wang T, Xie L, Wang W, You W, Wang L, Valev VK, Ji M, Zhang L. Nanoplastics Detected in Commercial Sea Salt. Environ Sci Technol. 2024 May 28;58(21):9091-9101. doi: 10.1021/acs.est.3c11021. Epub 2024 May 6. PMID: 38709279; PMCID: PMC11196019.
14. Saha SC, Saha G. (2024). "Effect of microplastics deposition on human lung airways: A review with computational benefits and challenges." Heliyon. 2024 Jan 11;10(2):e24355. doi: 10.1016/j.heliyon.2024.e24355. PMID: 38293398; PMCID: PMC10826726. PubMed

15. Smith, M., et al. (2020). "A global overview of microplastic contamination in marine organisms." Environmental Pollution, 259, 113227. PubMed

16. Syamsu, D.A., et al. (2024). 'Presence of microplastics contamination in table salt and estimated exposure in humans." Global Journal of Environmental Science and Management. Global J. Environ. Sci. Manage. 10(1): 205-224, Winter 2024, Serial #37
17. Taghipour H, et al. (2023). Incidence and exposure to microplastics in table salt present in the Iran market. Toxicol Rep. 2023 Jul 11;11:129-140. doi: 10.1016/j.toxrep.2023.07.003. PMID: 37520774; PMCID: PMC10372495. PubMed
18. Yang D, et al, (2015). Yang D, Shi H, Li L, Li J, Jabeen K, Kolandhasamy P. Microplastic Pollution in Table Salts from China. Environ Sci Technol. 2015 Nov 17;49(22):13622-7. doi: 10.1021/acs.est.5b03163. Epub 2015 Nov 2. PMID: 26486565.
19. Zhang Q, et al. (2020). Qun Zhang, Elvis Genbo Xu, Jiana Li, Qiqing Chen, Liping Ma, Eddy Y. Zeng, Huahong Shi. A Review of Microplastics in Table Salt, Drinking Water, and Air: Direct Human Exposure. American Chemical Society. March 2, 2020.