A deep dive into the safety of our daily food and the impact of microplastics on human health.

In recent years, there has been an increasing presence of microplastics in the food we eat and the water we drink. Now, a new study in Australia has found that agricultural soils currently hold around 23 times more microplastics than oceans. Moreover, these plastics in soil could be exposed to about 10,000 chemical additives, most of which are not regulated in agriculture.

“These microplastics are turning food-producing land into a plastic sink,” said Joseph Boctor, an environmental biotechnologist at Murdoch University, Australia, and lead author of the study. His team went through about 200 scientific papers and found that about 22,500 tonnes of microplastics end up in UK soils every year, just from fertilisers and additives.

These findings are alarming, especially when viewed alongside research on microplastics (MPs) found in the human body, including the brain, lungs, and even the placenta. In the World Economic Forum’s Global Risk Report 2025, microplastics were among the top ten risks, underscoring the need for urgent action.

To grasp the extent of the problem, it’s important to understand how plastic particles are categorised by size: macro- (>25 mm), meso- (25 mm–5 mm), micro- (5 mm–0.1 µm), and nanoplastics (<0.1 µm). Generally, nanoplastics and microplastics result from either the breakdown of macroplastics or are found in such sizes from manufacture. When it’s due to the former, they are referred to as secondary microplastics, and primary microplastics when resulting from the latter, the Food and Agriculture Organisation (FAO) report explains.

According to the FAO, the most common use of plastics is in packaging, followed by their use in construction, the automotive industry, electronics, and household materials.

The presence of MPs in the environment was first reported in the 1970s. Now, they are everywhere and have entered our food chain at a concerning rate.

Growing evidence of MPs in food

Rice is one of the most consumed grains across the world. In 2024–2025, China was the highest consumer with about 145 million metric tons, followed by India with 121 million metric tons. A 2024 study revealed a significant presence of MPs in the rice consumed in India, with about 30 microplastic particles per 100g. The findings underscore how deeply microplastics have infiltrated daily diets through such staple foods.

“We studied 10 rice samples of different brands and found microplastics in all of them. Today, everything is made of plastic for the sake of convenience and economic benefits. During storage and transportation, plastic is usually used to avoid moisture from seeping into the food products. So, in these different stages, microplastic fibres and particles are seeping into the products,” explains Anil Gore, lead author of Microplastic Contamination in Indian Rice: A Comprehensive Characterization and Health Risk Assessment.

While Boctor and team’s study is new, a 2022 study by the Indian environmental NGO Toxics Link, found a high amount of microplastics in soil samples from agricultural belts in Karnataka and Maharashtra. Both studies considered the practice of plastic mulching as a main contributor. Mulching is “a practice of covering the soil to retain soil temperature and moisture to facilitate higher crop production.”

The study found tiny plastic particles at various depths, indicating soil contamination due to the widespread use of plastic mulch sheets. “The plastic used for mulching is relatively thin, and the removal and recycling of these plastic films from the agricultural field are labour-intensive, costly, and challenging. Consequently, it remains in the field or is dumped nearby and ultimately disintegrates into micro-particles accumulating in the soil,” Priti Banthia Mahesh, Chief Programme Coordinator, Toxics Link, explained in the paper.

The study also highlighted the trend of improper handling of plastic films after harvest. They found that about 65% of farmers disposed of these non-biodegradable plastic sheets on agricultural land or the roadside, which leads to contamination of soils with MPs.

Image credit: The highest contamination levels in dairy products and human breast milk were found to be up to 2,590 MPs per litre in a study last year. Photo by Pixabay.

Milk, another widely consumed product, as well as breast milk, the main source of nutrition for newborns, have also been found to be contaminated with microplastics. In a 2024 study, the highest contamination levels in dairy products and human breast milk were found to be up to 2,590 MPs per litre.

MPs have also been found in seafood, fish, shellfish, and other marine organisms in different regions across the world. For instance, last year, a study reported the presence of MPs in four popular brands of canned seafood, which were purchased from two supermarkets in Porto, Portugal. Another study found that almost 73% of the freshwater fish samples from the Chi River in northeastern Thailand contained MPs in their gastrointestinal tracts.

Moreover, fruits such as apples and European pears collected from Catania markets in Italy have shown the presence of MPs. A 2020 study looked into honey samples from six different countries and found MPs in all of them.

In 2024, Toxics Link conducted an important study to detect the presence of MPs in essential cooking items: salt and sugar. The researchers analysed 10 types of salt and five types of sugar procured from online and local markets. They found MPs in all samples. The findings revealed an average concentration of 28 microplastic particles per kilogram of salt. The highest levels of MPs were found in iodised salt. Combined with data that, on average, an Indian consumes 10.98 grams of salt per day, this paints a disturbing picture about the impact of MPs on human health.

Another 2024 study found MPs in national and local bottled water brands collected from a market in Nagpur, India.

“Coming across findings that showed microplastics in drinking water was shocking for me. The more research I have done or read over the years, the more overwhelming the findings about microplastics have been. Nothing is left untouched by microplastics today. It’s deeply concerning and is a great threat to human health,” Satish Sinha, Associate Director of Toxics Link, says.

Impact on health

In 1950, global annual plastic production was 2 million tons (Mt), which by 2021 had increased to over 390 Mt. Today, these inescapable particles have not only become a major environmental concern but also a major health risk.

MPs have been found in several human body parts, including head hair, saliva, lungs, liver, placenta, faeces, kidneys, and blood samples. Usually, they are either ingested, inhaled, or absorbed through skin contact.

A 2024 study found that MPs lead to serious health issues, including various cancers, respiratory disorders, and inflammatory bowel disease. Another study showed that exposure to MPs increases the expression of inflammatory factors and affects embryo development.

Earlier this year, researchers discovered that in the average brain sample, the amount of plastic found is about equivalent to a plastic spoon. Furthermore, they found that people who died in 2024 had more nanoplastics in their brain samples than those who died in 2016.

In the new study, Boctor and his team also pointed out the harmful effects of additives, such as phthalates and PBDEs, in soils. These have been linked to neurodegenerative diseases, increased risks of stroke and heart attack, and early death, they note in the press release.

“The problem is that unless you can directly link MPs to a disease and say that it’s affecting a high number of people, others don’t listen to you about the health impacts,” says Sinha.

He says it’s concerning that healthcare professionals are not talking about this. “As long as the medical community keeps treating only symptoms of diseases such as cardiovascular disease and doesn’t look into the root cause, the impact of MPs will be overlooked. Is there some change in human physiology? Is there a biochemical change? Why do all these people have this excess of microplastics in their blood? These are some important questions today. There is also no testing for MPs in the human body,” he further explains.

Need for action

Currently, Boctor is working on creating a type of plastic that is not only safe but also decomposes in soil, land, and water. Sinha says researching and finding materials like these that have similar properties to plastics but are not as dangerous is one of the keys to mitigating the global health risk of MPs.

While completely stopping the use of plastic is not a plausible solution, given the extensive dependence of the world on it and the lack of alternatives at a similar price that offer the same diversity in use, it’s important to find ways to reduce dependence, Gore points out.

He also adds that it’s important to identify the different sources of contamination and address them directly. Sinha agrees and gives an example: “Now that we know how plastics end up in water bodies, which leads to people ingesting them, can we not prevent them from going into landfills or water systems such as lakes and dispose of them better? Can filtration systems for watering plants be strengthened? Are the reverse osmosis systems for drinking water in households removing MPs, and if not, can the system be improved?” he adds.

Sinha also stresses the need to determine a safe threshold for daily microplastic intake. He advocates for clear safety standards for food and drinking water, so individuals have a way to monitor their exposure. “These guidelines must be effectively communicated, allowing people to verify whether they are being followed,” he adds.

Both Gore and Sinha emphasise the need for more research on the impact of MPs on human health as well as the need for urgent action.