People Are Ingesting Microplastics At Levels That Are Causing Physical Harmful Effects


Microplastics have invaded the earth and it’s a problem. According to the National Ocean Service, microplastics are ‘small plastic pieces less than five millimeters long which can be harmful to our ocean and aquatic life.’

In a groundbreaking study, researchers looked into what levels of environmental microplastics (MPs) in human cells may eventually lead to allergic reactions, harm, or death. During their focus on the MP contamination of commonly used environmental sources, they discovered that cellular harm can happen when humans consume high amounts of substances that come from such sources.

The researchers suggest that there should be future attempts at MP mitigation in the environment precisely for the safety of the human population.

Published in the Journal of Hazardous Materials, the new study was done by researchers from the University of Hull, as well as the lead author and doctoral candidate at Hull York Medical School in York, United Kingdom, Evangelos Danopoulos.

According to Danopoulos, “Our research shows that we are ingesting microplastics at the levels consistent with harmful effects on cells, which are in many cases the initiating event for health effects.”

Publication Medical News Today spoke with Danopoulos, who shared his team’s findings from three previous studies that he conducted with the Human Health and Emerging Environmental Contaminants research group at the University of Hull.


Finding MPs In Everything

As mentioned earlier, MPs are tiny plastic particles that are smaller than 5 millimeters (mm). They form due to a number of reasons such as mechanical and environmental degrading of plastics, as well as through condensation through the heating or burning of plastics in the atmosphere.

What they researchers founds was that there were MPs in everything from the deep ocean, Antarctic ice, and Arctic snow. They were also found in table salt, seafood, and drinking water, which became the focus of these studies and how they relate to humans.


Effects of Concern on Humans

The study concentrated on five variable effects of microplastics contamination on the human cells, which are the ‘survival or death of a cell, effect on cellular immune response, ability to penetrate the cell wall, level of cellular damage, and ability to alter cell genetic structure.

In the analysis, they saw that the first four effects had an impact on the cell health. It also showed that the cell survivability was dependent on the shapes of the microplastics, where the irregularly-shaped MPs were the ones that were most harmful and were the probable cause of cell death.


Where Human Exposures are Most Common

According to the study, here are the most common sources of human exposure to microplastics:



Since MPs are known to have contaminated all elements of the marine environment, which include seafood. One of the two major uptake routes identified for human exposure to microplastics was from human ingestion from such marine sources, while the other one is from inhalation.

Since people eat seafood in a number of ways, such as whole like with oysters, or in parts, like with crab legs. But understanding which fish are the most contaminated, or which body parts hold the most MPs, is one way to discern how much seafood toxicity there could be during human consumption.


Table Salt

In more recent years, there has been a growing concern about the potential health effects of table salt. There are a variety of salts found on the market that can contribute to human cells toxicity, depending on one’s exposure of course. These salts include sea, rock, well, and lake salts.

While the degree of contamination from these salts can vary substantially dependent on these environmental sources, the analysis from the study is the confirmation that human exposure to salt proves they carry MPs.


A Variety of Water Sources

A number of studies have shown that tap and bottled water are both sources for human body contamination of MPs. Some toxicology studies show that the toxic effects of microplastics in drinking water also depends on the amount of water people consume.

While MPs exist in all aquatic life environments, their contamination levels will probably continue to rise as there is also an increase in plastic use, production, and waste.


More Research Needed

There are some concerns and other limitations to the study of course. According to Danopoulos, he told MNT, “There is great uncertainty around what happens after we consume microplastic contaminated food. We do not know how much has the potential to stay in our bodies, cross the gut barrier, or just be excreted. This will ultimately define how hazardous the microplastics can be to us.”

He added, “So far, most toxicology studies have been testing spherical microplastics. There needs to be a shift to testing irregularly shaped ones. We [also] need to focus on animal studies to understand how the microplastics behave after they are inside our bodies. However, the biggest uncertainty at the present time is how ingested microplastics are excreted from the body. This is a crucial point to understand the true level of risk.”

In the study, because they didn’t have human test subjects, the research team used human cell lines instead, which were considered acceptable sources of scientific evidence for human health effects.

During the current study, they also used controlled conditions in order to predict what would happen during real-life environmental conditions, as well as ‘predicting system-based effects from cell-based ones.’ Yet, they admit that further studies ‘will need to make adjustments based on these variables in their risk assessment process.’


Moving Forward

In conclusion, Danopoulos said, “I feel the findings highlight that there are a lot of issues around microplastics and their potential effects that we do not fully understand.”

Unfortunately in the meantime, microplastics will continue to rise all over the world due to continuous plastic production and use. If the mismanagement of use and production continue to consistently rise, the ecological risks from MPs will become so widespread that ecosystems across the globe will feel their majorly adverse effects within the next century, or even worse, in less time than that.