How Do Microplastics Affect Our Health?

In recent years, entities such as the World Health Organization have spoken of the need for more research on how microplastics affect our health. What do we know so far? Find out in this article!
How Do Microplastics Affect Our Health?

Last update: 06 June, 2021

We know that we’re exposed to a large number of pollutants in our daily lives. One of them is microplastics. But how do microplastics affect our health? Are they harmful?

Let’s take a look at the main conclusions that science has reached so far.

What are microplastics and where do we find them?

Microplastics are very small solid particles of plastic material. In fact, they’re particles that are smaller than 5 microns. Currently, they can be classified into primary and secondary microplastics.

Primary microplastics are manufactured specifically in such small sizes to be part of the manufacturing of certain products. On the other hand, secondary microplastics appear as a result of the degradation of larger plastic parts.

In general, it’s the action of the sun, wind, and waves that end up eroding the plastic in the sea, and these very small plastic pieces end up appearing.

Deliberately added microplastic particles (or primers) are used in a large number of products marketed worldwide. They cover a wide variety such as:

  • Fertilizers and other plant protection products
  • Cosmetic products (make-up, glosses, scrubs)
  • Household and industrial detergents
  • Cleaning products
  • Paints

Given their high presence, some organizations, such as the European Chemicals Agency, advise restricting the deliberate use of this type of particle by industry.

Do microplastics affect our health negatively?

A person getting ready to enjoy a plate full of plastic waste.
To date, the impact of microplastics on the body is unknown. While experts suspect that they’re harmful, more studies are necessary.

The impact of plastics on the marine environment is beyond doubt. However, the consequences on people’s health can’t be so conclusive, as there’s currently a lack of data to evaluate it.

In 2014, the European Food Safety Authority (EFSA) classified this type of particulate matter as “a potential emerging risk”. However, in the same study, it made clear the lack of analysis and scientific data to know how they affect health to establish recommendations for the general population.

For the moment, we know that our bodies don’t absorb particles that are larger than 150 microns. And the smallest particles also seem to have a very small absorption. On the other hand, if we’re talking about nanoparticles (very, very small plastic particles), there could be a greater absorption.

For this reason, a greater number of studies are necessary to be able to evaluate more accurately how our bodies absorb these particles and what their toxicity is.

How do they reach our bodies?

One of the main routes of contact of microplastics with humans is through the food chain. They’re present in the environment (especially in the marine environment) and fish, livestock, and poultry can ingest them.

However, in general, animals don’t consume microplastics and, if they do, they accumulate in the intestines and stomach (and are then eliminated). So, we can say that this contact pathway is small.

This isn’t the case with crustaceans and bivalve shellfish, as they’re consumed whole. Moreover, not only do we find microplastics in animals; we’ve also found them in other products such as honey, beer, sea salt, and in drinking water–both tap water and bottled water.

Apart from these food pathways, contact may derive from other sources as well. The impact of cooking or baking on the presence of microplastics in food is not known at this time. We also come into contact with them through many everyday products such as cosmetics, detergents, textile fibers, or machinery.

Pollutants associated with microplastics

A pile of empty plastic water bottles.
Microplastics may contain other pollutants that are harmful to human health.

For the time being, it’s clear that more research is necessary to determine the degree of toxicity that microplastics may have on human health. But some experts are also concerned about the action of the pollutants that may be associated with them.

Microplastics can contain about 4% of additives, while they can also absorb some contaminants. And the latter can be dangerous to human health.

Perhaps the most well-known of these is bisphenol A, a chemical compound widely used in the manufacture of plastics, that’s been recognized as an endocrine disruptor. At the moment, there’s a ban on its use in some types of packaging, such as baby bottles. We’re also talking about phthalates, polycyclic aromatic hydrocarbons (PAHs), or polychlorinated biphenyls (PCBs).

Endocrine disruptors are substances that alter our hormonal system and can lead to diseases such as certain types of cancer, metabolic disorders, reproductive problems, or cardiovascular diseases.

However, nowadays, we find these chemicals in a large number of products, and the percentage that reaches us through microplastics is very small.

How do microplastics affect our health? More research is needed

Humans are exposed to both the ingestion and inhalation of microplastics. The toxicity and health problems associated with them depend in part on the size, associated chemicals, and dose.

Although scientists have been collecting data for about a decade, it’s important and necessary to focus on this pollutant and its potential effect on human health.

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