Microplastics in food: what we know and what we're waiting for
Microplastics have been found in mussels, salt, honey and bottled water. But how much we actually swallow, and what it does to our health, nobody can yet say with confidence. Here is what has been measured, what is still unclear and what the authorities are preparing.
Microplastics in mussels, in sea salt, in honey, in bottled water. Every new study makes headlines, and you end up wondering whether anything on your plate is still "clean." The honest answer fits in two sentences: yes, they turn up almost everywhere in our food, and no, we don't yet know whether the amounts we swallow cause a health problem.
Between those two statements lies a lot of nuance. Here is what the European Food Safety Authority (EFSA), Health Canada and the World Health Organization (WHO) say, keeping a clear line between what has been measured and what remains uncertain. No panic, no promises: just the state of knowledge as of October 2026.
Micro, nano: what exactly are we talking about?
For EFSA, a microplastic is a plastic particle between 1 micrometre and 5 millimetres in size. The largest are smaller than a grain of rice; the smallest are invisible. Below 1 micrometre, we speak of nanoplastics, which range from 1 to 1,000 nanometres. These particles mostly come from larger pieces of plastic breaking down: packaging, clothing fibres, tires, objects left in the environment.
Two features complicate everything. They are persistent, so they build up in the sea, soil and air, where their quantities are increasing according to EFSA. And they are so small that they are hard to detect and count. That is especially true of nanoplastics, precisely the ones that could most easily enter the body. To understand where they come from in the environment, our article on microplastics in the oceans covers the question.
What has been measured: they are in food and in water
On this point, the authorities agree. EFSA reports that microplastics have been detected in mussels, meat, honey, vegetables, beer and table salt, and that they can also enter the food chain through drinking water. The Science assessment of plastic pollution, published in 2020 by Environment and Climate Change Canada and Health Canada, paints a similar picture: most of the data concern fish and seafood, where particles were found in muscle and in the digestive tract, as well as in shellfish such as mussels, clams, oysters and scallops. Very few other foods, such as salt, have been studied.
That last detail matters. If seafood keeps coming up in the headlines, it is partly because it is the food that has been analyzed the most, not necessarily because it is the most contaminated item in the grocery store. We simply don't know much about the rest of the plate.
As for water, the Canadian assessment notes that microplastics were found in bottled water purchased outside Canada, at concentrations that did not depend on the type of container. In tap water, results are mixed: some studies detect them, others don't, and drinking water treatment is expected to remove a large share. WHO points the same way in its 2019 analysis: conventional drinking water treatment can remove particles even smaller than one micrometre.
Containers themselves can also release them. A study published in 2020 in Nature Food measured up to 16.2 million particles per litre released by polypropylene baby bottles, and sterilization and very hot water clearly increased that release. The authors stress, however, that whether these levels pose a risk to babies' health still needs to be assessed. We go into more detail in our article on baby bottles and children's dishes.
What remains uncertain: how much we actually swallow
Knowing that a food contains microplastics is not the same as knowing how much we ingest. And here, the numbers become much shakier. The Canadian assessment is clear: without standardized methods to sample, detect and count particles, human exposure cannot be quantified. EFSA has said the same thing since its first statement in 2016, and again after a scientific colloquium in 2021: harmonized methods and data are lacking, especially for nanoplastics.
The most widely cited estimate was published in 2019 in Environmental Science & Technology. Compiling 26 studies, the researchers estimated that an American swallows 39,000 to 52,000 particles a year through food, and 74,000 to 121,000 when you add what they breathe. Those are striking figures, but they need to be read with their limits: they are based on foods that represent only about 15% of calories consumed, they vary enormously, and the authors themselves consider them probably underestimated.
There is also some good news on the measurement side. In October 2025, a literature review published by EFSA concluded that the amounts of micro- and nanoplastics migrating from food contact materials (containers, utensils, packaging) are considerably lower than some earlier studies suggested. The same review still flags data gaps. In short, the first alarming numbers don't always hold up under more rigorous methods, which calls for even more caution with any precise estimate.
What the authorities say about health
The starting point is size. According to WHO, microplastics larger than 150 micrometres are unlikely to be absorbed by the body, and uptake of smaller ones is expected to be limited. Nanoplastics may be absorbed and distributed more easily, but data on them are extremely thin. In 2019, based on the available information, WHO judged that microplastics in drinking water did not appear to pose a health risk at current levels, while calling for more research.
Canada's 2020 assessment reaches a similar conclusion, with the same caveat. The scientific literature does not identify a concern for human health, but the data are insufficient for a robust risk evaluation. In animals, oral exposure has been associated with liver inflammation, oxidative stress, metabolic changes and altered gut microbiota. In humans, effects have mostly been observed in the workplace, through inhalation, notably respiratory symptoms. These observations cannot, however, be applied to the exposure of the general population. As for the chemicals carried by plastics, the international reviews cited in the report consider them a likely low concern in food and water.
EFSA, for its part, is not taking a position yet: it has not carried out a full risk assessment and therefore cannot conclude on health effects. It also points out that it assesses risks but does not set limits; governments are the ones who regulate.
| Question | What we know | What remains uncertain |
|---|---|---|
| Are they in food? | Yes: seafood, salt, honey, beer, meat, vegetables, water | Levels in most foods, which are rarely studied |
| How many do we swallow? | Estimates exist, in the tens of thousands of particles a year | No reliable measurement, for lack of standardized methods |
| Are they absorbed? | Particles larger than 150 µm are poorly absorbed, according to WHO | How nanoplastics behave in the body |
| Health effects? | Effects seen in animals and in highly exposed workers | Effects at the exposure levels of the general population |
The studies that make headlines: how to read them
In March 2024, a study published in the New England Journal of Medicine made the rounds worldwide. In patients having plaque removed from the carotid artery, the researchers found polyethylene in the plaque of 58.4% of the 257 patients followed, and PVC in 12.1% of them. Over a follow-up of about 34 months, those whose plaque contained micro- or nanoplastics had a higher risk of heart attack, stroke or death than the others.
It is a serious result that justifies pushing research further. But the authors write it themselves: their results do not prove cause and effect. The study is observational, other lifestyle or exposure factors could explain the difference, laboratory contamination cannot be completely ruled out, and the patients all had already advanced artery disease. We also don't know where those plastics came from: food, water, air?
That is the right lens for most headlines on the subject. Finding particles in an organ or tissue is a measurement. Concluding that they cause a disease requires other kinds of studies, and that is precisely what is still missing.
What we're waiting for: the next milestones
Things are moving. On December 9, 2025, EFSA announced that the European Parliament had asked it for scientific advice on the risks of microplastics in food, water and air. The opinion is to review how particles enter the body and what effects they have, their transfer into food and the methods for assessing risks, and, if the data allow, update dietary exposure estimates. It is expected by the end of 2027. EFSA is also holding a public webinar on micro- and nanoplastics on October 20, 2026.
In Canada, Health Canada announced in January 2024 funding of $2.1 million over four years for research at McGill University, Memorial University of Newfoundland and the University of Toronto. The projects look at exposure through food and food packaging, drinking water, indoor and outdoor air and dust, as well as health effects and new measurement methods. They target precisely the gaps identified in the 2020 assessment.
In other words, within two years we should have more solid answers. Until then, any categorical claim, in either direction, goes further than the science.
In the meantime: reasonable steps, without worrying
Since the risk has not been established, none of the authorities cited here give specific instructions for reducing microplastics on your plate. A few simple steps are nonetheless in line with the available data, and they have the advantage of reducing waste too:
- Drink tap water. Drinking water treatment removes a large share of the particles, and according to the 2019 estimate, drinking only bottled water would add about 90,000 particles a year, compared with about 4,000 for tap water.
- Avoid heating food in plastic. Heat increases particle release, as the baby bottle study showed. Our pillar article on microwaving plastic and bisphenols explains what Health Canada says on the subject.
- Think about the air too. According to the 2019 estimate, we would breathe in almost as many as we eat. Indoors, the main source identified by the Canadian assessment is fibres from clothing, furniture and carpets. Our guide to limiting microplastics day to day covers the kitchen, water, air and clothing.
- Keep eating a varied diet. No authority recommends avoiding seafood or any particular food because of microplastics.
And in the longer term, the most useful step remains a collective one: less plastic in the environment means fewer particles in the food chain. That is in fact the shared recommendation of WHO and the Canadian assessment. If you want to start at home, our plan to cut down on plastic begins with an audit of your garbage can.
Sources
- Microplastics and nanoplastics in food, European Food Safety Authority (EFSA), page consulted in 2026.
- Microplastics: European Parliament requests scientific advice from EFSA, EFSA, 2025.
- Science assessment of plastic pollution, Environment and Climate Change Canada and Health Canada, 2020.
- Le gouvernement du Canada finance la recherche sur les risques des microplastiques pour la santé (in French), Health Canada, 2024.
- WHO calls for more research into microplastics and a crackdown on plastic pollution, World Health Organization, 2019.
- Human Consumption of Microplastics, Cox et al., Environmental Science & Technology, 2019.
- Microplastic release from the degradation of polypropylene feeding bottles during infant formula preparation, Li et al., Nature Food, 2020.
- Microplastics and Nanoplastics in Atheromas and Cardiovascular Events, Marfella et al., New England Journal of Medicine, 2024.
Frequently asked questions
Are microplastics in food dangerous to health?
We don't know yet. Canada's 2020 science assessment did not identify a concern for human health, while stating that the data are insufficient for a robust risk evaluation. EFSA has not yet carried out a full risk assessment and therefore cannot draw a conclusion.
Which foods have microplastics been found in?
EFSA mentions mussels, meat, honey, vegetables, beer and table salt, as well as drinking water. According to the Canadian assessment, most of the data concern fish and seafood, and very few other foods have been studied.
Does bottled water contain more microplastics than tap water?
An American estimate published in 2019 gives about 90,000 additional particles a year for someone who drinks only bottled water, compared with about 4,000 for tap water. These estimates vary widely, but they point the same way as the Canadian assessment, which says drinking water treatment removes a large share of microplastics.
When will we know whether microplastics are a risk?
EFSA is preparing a scientific opinion requested by the European Parliament, expected by the end of 2027. In Canada, Health Canada has been funding research on exposure and effects since 2024, including at McGill University.
Should I stop eating seafood because of microplastics?
None of the authorities cited here recommend it. Seafood is the most studied food, which partly explains why it gets so much attention, but no limit or consumption advisory related to microplastics has been published.
