The introduction of plastic in all industries was the greatest exponent of development some years ago. This petroleum-derived material, among other raw materials, has stood out since then for its extraordinary malleability and resistance capabilities.
However, the recovery and recycling of plastics remains one of the biggest challenges of the 21st century. To all this has been added the omnipresence of microplastics, an even greater threat since they are the result of the slow disintegration of plastic waste.
What are microplastics?
Microplastics are very small solid particles made up of mixtures of polymers (the primary components of plastics) and functional additives. Although there is no consensus on what size they can be considered microplastics, the National Oceanic and Atmospheric Administration (NOAA) uses the parameter of less than five millimeters in diameter to refer to them.
For their classification, it is usual to resort to the distinction of microplastics according to their origin, although the true origin of these plastic fragments can be very varied:
- On the one hand, all those tiny plastic particles that are used to complement other products or additives are considered primary microplastics. Cosmetic and hygiene products, as well as a large number of cleaning products, for example, incorporate what is known as microbeads. Fortunately, these plastic microspheres have already been banned in several countries such as the United States, Canada, the United Kingdom, France, Sweden or New Zealand.
After the publication in 2015 of a scientific study in the journal Environmental Science and Technology that warned of the dangers of incorporating plastic microspheres in everyday products, the best-known brands began to progressively adapt to the new regulations issued mainly by European countries. In June 2020, the draft bill on waste and contaminated soils was approved in Spain by the Council of Ministers associated with the framework of the Spanish Circular Economy Strategy, which provides for the prohibition of cosmetics and detergents that contain microplastics intentionally added as of March 3. July 2021.
- On the other hand, secondary microplastics are those that come from the degradation or separation of other elements. That is, they are all those small pieces that end up becoming plastic particles and that are detached from plastic objects such as bags, bottles or fishing nets during their long degradation process.
The most worrying facts about microplastics
Since they do not biodegrade, microplastics can remain in the environment for centuries, while single-use plastic often has an average shelf life of 12 to 15 minutes.
However, beyond their slow degradation as they become smaller and smaller parts, they pose a terrible threat to nature. Microplastics end up being absorbed or ingested by many animals, especially in the marine environment, causing their poisoning.
In August 2019, the World Health Organization (WHO) concluded that, after a first investigation, the presence of microplastics in bottled water did not pose a health risk at the levels found. However, the authors of the same study admitted basing their conclusions on limited information and called for further research on this matter.
In the same period, it was detected that the snow that fell in the Arctic, one of the purest places on the planet, contained microplastics at a rate of more than 10,000 particles per liter.
A year later, Spanish researchers from EnviroPlaNet, the Thematic Network of Micro and Nanoplastics in the Environment granted by the Ministry of Science, Innovation and Universities, carried out a pioneering sampling of plastic particles between 1,500 and 2,500 meters high flying over urban areas and rural areas in the center of the country with the help of planes from the Mixed Group of the Air Force. The results were chilling, since it is estimated that approximately one trillion plastic particles float over the center of Madrid, a quantity that is nevertheless considerably reduced in unpopulated areas.
The study entitled “Human Consumption of Microplastics” from the University of Victoria revealed important information about the introduction of microplastics into the diet of citizens, as it estimates that we inhale between 74,000 and 121,000 plastic particles per year unconsciously.
Recycling and recovery of plastics, the only way out
Although there are already numerous technological proposals for cleaning microplastics in the natural environment, the most obvious way to combat this emerging threat is to encourage recycling and promote the recovery of plastics.
While only 9% of the plastic used in the world is recycled (12% is incinerated and the remaining 79% is abandoned in landfills or in the environment), the use and energy recovery of plastic waste represents a great opportunity to power generation in other industries. That is, what we know as Plastics to Energy (P2E).