The Scale of the Problem: How Widespread Is Microplastic Contamination in Salt?
Research shows microplastics appear in roughly nine out of ten table salt brands sampled worldwide. Of 39 salt brands tested, 36 contained microplastics, according to an analysis by researchers in South Korea and Greenpeace East Asia. That figure alone is striking.
A global review of microplastic contamination in table salts found that 94 percent of salt products tested worldwide contained microplastics, with three out of 27 polymer types, specifically polyethylene terephthalate, polypropylene, and polyethylene, accounting for the majority of all particles.
Although research in this field is still in its early stages, this growing body of evidence suggests that continuous exposure to microplastics through dietary salt represents an emerging threat to human health.
Sea Salt: The Most Contaminated Salt Type
A study published in Environmental Science and Technology, a peer-reviewed scientific journal, analyzed 39 salt brands globally and showed that plastic contamination in sea salt was highest, followed by lake salt, then rock salt, an indicator of the levels of plastic pollution in the areas where the salt was sourced.
In research examining Chinese salt brands, microplastics content measured 550 to 681 particles per kilogram in sea salts, compared to 43 to 364 particles per kilogram in lake salts, and just 7 to 204 particles per kilogram in rock or well salts.
Unlike rock salts which are mined underground and formed in pre-modern times, sea salts and lake salts are usually produced through a crystallization process whereby seawater or brine is evaporated by heat and wind. Therefore, pollutants found in these waters, including microplastics, find their way into the end product.
Indonesian Sea Salts: The Highest Contamination Levels Recorded
In one Indonesian sea salt sample, researchers found the highest quantities of microplastics of any sample tested. The country is considered to be the second worst plastic emitter into the world’s oceans.
Salt is produced on Madura Island, Indonesia, by evaporating seawater, an ancient technique. Research found that salt made in this region contains some of the highest microplastics levels of any samples collected.
A 2024 study published in the Global Journal of Environmental Science and Management found microplastics were detected in significant amounts in all salt samples tested, ranging from 33 to 313 particles per kilogram. The types most commonly found were fragments at roughly two thirds of all particles, followed by fibers, films, and pellets. The polymer types identified included polyethylene, polypropylene, polyethylene terephthalate, and polyester.
Himalayan Pink Salt: Surprisingly High Contamination
A study published in the Journal of Environmental Science and Pollution in July 2022 analyzed seven common Australian commercial salts, including fine and coarse Himalayan pink salt. Microplastic contamination was found to be higher in terrestrial salts such as black salt and Himalayan pink salt compared to marine salts, with the highest content coming from Himalayan salt.
The study suggests that the contamination in mined salts might have originated from manufacturing, packaging, atmosphere, or storage processes. In other words, it is not only ocean pollution that drives the problem. The processing chain itself can introduce particles.
A 2023 study testing multiple salt types, including coarse Himalayan pink salt, found that coarse Himalayan pink salt carried the highest microplastics load of all the varieties tested.
Table Salt and Rock Salt: Not Off the Hook
Since table salt is typically refined from underground deposits, microplastic contamination is likely to happen during the extraction of seawater and manufacturing processes. A 2024 study published in the Global Journal of Environmental Science and Management found table salt contains a significant number of microplastics, detecting up to 33 microplastics per kilogram of table salt.
Research examining 40 table salt samples in Iran found that all of the salts tested were contaminated with microplastics. The overall abundance ranged from 700 to 5,470 microplastic particles per kilogram. The abundance was notably higher in counterfeit and non-standard salts.
The main origin of salt contamination with microplastics is most likely related to environmental pollution, while another portion can be attributed to salt processing and packaging.
The 5 Salt Types and Brands Most Frequently Flagged in Tests
No single global test has produced one definitive list of five named consumer brands confirmed to contain microplastics across all markets. What research consistently identifies, however, are five categories of products that repeatedly appear in contamination findings: Indonesian commercial sea salts, Asian-sourced sea salts broadly, coarse Himalayan pink salt products, standard refined table salt brands, and bulk or non-standard salts sold without quality certification.
Consumer organization Mamavation sent 23 salt products to an EPA-certified laboratory to test for heavy metals and microplastics across well-known brands in the United States. The laboratory looked for microplastics using Fourier Transformed Infrared Spectroscopic imaging. Microplastics were found, though they were not at high enough levels for the test to conclusively identify what type they were.
Based on the research reviewed by multiple independent analysts, salt sourced from Asia may carry the most microplastic contamination, followed by Pacific Sea Salt, Celtic Sea Salt, and Himalayan Rock Salt.
What Polymers Are Actually Found Inside Salt?
Microplastics measuring less than 200 micrometers represented the majority of particles in one major study, accounting for roughly half of all microplastics found, with the most common polymers being polyethylene terephthalate, followed by polyethylene and cellophane in sea salts.
Polymer types identified across multiple studies include polyethylene, polypropylene, polyester, polyethylene terephthalate, polyamide, and polyvinyl chloride, among others. These are plastics found in everyday items from water bottles to synthetic clothing.
The dominance of fibres in salt contamination is often attributed to the widespread use of synthetic textiles, particularly polyester, whose durability and resistance to degradation allow it to persist in the environment in fibrous form.
How Much Are We Actually Ingesting Each Year?
Assuming an intake of 10 grams per day of salt, the average adult consumer could ingest approximately 2,000 microplastics each year through salt alone. Even after discounting the highly contaminated Indonesian salt sample, the average adult could still be consuming many hundreds of microplastics each year.
Microplastic contamination of salt varies significantly between types: sea salt ranges from 0 to 1,674 microplastics per kilogram, lake salt from 8 to 462, and rock and well salt from 0 to 204. The majority of samples across all origins were found to be contaminated, confirming salt as a genuine carrier of microplastics.
Research on Iranian salt consumption estimated daily intake for adults at roughly 6.5 to 53.6 microplastic particles per person per day, translating to thousands of particles annually depending on consumption habits and brand.
What Do Microplastics Actually Do Inside the Human Body?
Microplastics have now been detected throughout the human body, including in the blood, saliva, liver, kidneys, and placenta. Investigators are actively probing how they migrate to other organs and tissues from the lungs and gastrointestinal tract.
A 2025 comprehensive review integrated recent findings on the sources, classification, and pathways of microplastics into the human body, highlighting their potential cellular toxicity and systemic health risks. The review discusses mechanisms by which microplastics may induce inflammatory responses, oxidative stress, and cellular damage, thereby contributing to various diseases.
Research conducted on rats and fish suggests that microplastics can activate an inflammatory response and damage cells. Depending on particle size, microplastics may cross the blood-brain barrier, may cross the placenta, and may cross cell membranes. The long-term implications of these pathways for human health are still being studied.
Are Any Salts Actually Safe? What Brands Do Better
Of the 39 salt brands studied in the landmark global analysis, only three did not contain any microplastic particles in replicated samples. The three table salts that did not contain the substance were sold in France, Taiwan, and China. The lesson here is that cleaner options exist, but they require careful sourcing.
Redmond’s Real Salt sources its product from an ancient salt deposit in Utah that has not been exposed to the modern ocean. One paper found salt from Utah to have some of the lowest levels of microplastics recorded in any study.
Selina Naturally’s Celtic Sea Salt is harvested from the coastal regions of Brittany, France, using ancient methods that preserve the natural mineral content of the salt. The company’s dedication to quality and purity means their salt undergoes thorough testing to ensure it is free from microplastics.
What the Science Still Does Not Know
The determination of microplastics in salt remains a significant analytical challenge due to the absence of internationally standardized protocols. This lack of harmonization hinders data comparability between studies and complicates efforts to assess contamination levels globally.
The study of whether and how microplastics pose threats to human health is still in its infancy. As the World Health Organization underscored in a 2022 report, current technologies do not yet enable researchers to quantify population-level microplastic exposures or gauge what proportion of those particles remain in our bodies.
Microplastics have been identified in various human tissues. While laboratory studies have shown that microplastics can cause damage and adversely affect physical functions at multiple levels, significant knowledge gaps persist, including uncertainties regarding the dose-response relationship, specific target organs, and the underlying toxicological mechanisms.
Conclusion: A Reason for Caution, Not Panic
