Microplastic-free – what does that actually mean?
The rezemo coffee capsules are not only based entirely on renewable raw materials, but are also free of microplastics. But what does the term microplastics actually mean? Why are the rezemo coffee capsules microplastic-free and why is that an advantage? We will answer these questions for you in this blog post.
"Would you eat a credit card?" - This and similar headlines appeared in the media last summer [1]. The background is a study on microplastics and their spread in the environment. The small particles are not only found in landfills or in the ocean. They also enter the food chain and thus the human body via various routes. A strange idea and certainly not good for your health. What is particularly shocking is that the amount of a credit card (5 grams) does not find its way into the human organism over the course of a year - but weekly. Reason enough to take a closer look at this special form of plastic.
A Little Plastics Science
To understand what the term microplastics means, it helps to look at the basic structure of plastics. Plastic, synthetic materials, polymers - all of these terms describe the material that has, on the one hand, led to incredible progress in many areas of life. On the other hand, it has also become a major cause of the increasing littering of our earth.
The smallest building block of plastics are the monomers, which is already clear from the name (“mono” is the Latin word for “one”). These small molecules consist mainly of the elements carbon (C) and hydrogen (H). They can be combined to form large, long-chain polymers using various chemical reactions. Here, too, the name says it all – “poly” means “many” in Latin. Similar to a string of pearls, a polymer consists of many individual monomers that are linked together. In order for these individual chains to become a processable material, they must stick together. This requires the addition of various auxiliary materials (additives). Only this combination of polymers and additives is referred to as plastic, or colloquially as plastic.
Fossil vs. bio-based plastics
Plastics can be of fossil origin or bio-based. The classic method of plastics production begins with the fossil fuels petroleum and natural gas. They are processed through various processing steps to form basic polymers and finished plastics, such as polypropylene (PP).
Bio-based plastics , on the other hand, are made from a biological or renewable raw material. They can be produced in various ways. Their precursors, the bio-based polymers, can be obtained entirely from nature. This is the case with the bioplastic PHA (polyhydroxyalkanoates), for example. These are then simply processed into plastics with the help of additives. In the case of PLA (polylactide), however, nature provides the corresponding monomers. These are then linked to polymers and further processed into plastics. Important at this point: The origin of the building blocks (monomers, polymers) does not necessarily have an influence on the properties and structure of the respective plastic. Monomers for the fossil plastic polypropylene can also be made from renewable raw materials instead of petroleum.
Conversely, it is also possible to produce biodegradable plastics from fossil resources. Biodegradability enables the plastic to decompose in composting plants and is explained in more detail below. The term "bioplastic" includes bio-based and biodegradable plastics as well as plastics that combine these two properties .
What is behind the term microplastics?
Microplastics are often associated with cosmetic products. They do indeed play a role here, particularly in the form of abrasive particles in peelings or cleaning products. The Federal Environment Agency defines the term microplastics as “ plastic particles that are five millimeters or smaller ” [2]. The decisive parameter that distinguishes microplastics from “normal” plastic (macroplastics) is the size of the particles.
types of microplastics
There are two different types of microplastics: primary and secondary microplastics. In the example mentioned, the abrasive particles in cosmetics, the plastic particles are manufactured for this purpose. These are accordingly referred to as primary microplastics. In addition, secondary microplastics in particular endanger the environment. In contrast to primary microplastics, secondary microplastics are created by the physical decomposition of larger plastic objects (macroplastics).
The above definition of microplastics only includes water-insoluble, i.e. solid particles. Environmental organizations such as Greenpeace define the term microplastics even more broadly [3]. In addition to solid particles, they also count water-soluble polymers as microplastics. This is because these substances can also have ecotoxic effects. Water-soluble polymers are contained as additives in detergents and cleaning products, for example. They can enter our rivers and lakes via wastewater. These substances are suspected of negatively affecting the hormone balance of the fish living there and thus damaging the ecosystems in the long term.
How does microplastic get onto our plates?
Regardless of whether they are water-soluble or solid particles, a large proportion of microplastics enter our environment via wastewater. Some of them are washed into our waterways and thus also into our drinking water. In addition, sewage treatment plants capture large quantities of plastic particles in the remaining sewage sludge. This in turn is often used as fertilizer on agricultural fields. This closes the circle of microplastics being absorbed through food. In Germany, a total of 9,696 tons of microplastics were brought onto farmland with sewage sludge in 2016 [4].
The mere idea of ingesting plastic through food is already repulsive. In addition, the effects of these particles on the organism and health have so far been little researched. What is certain is that they can cause physical damage to the gastrointestinal tract. This means that they can displace or hinder food intake, especially in animals. It is not for nothing that images of starving sea creatures dying with a stomach full of plastic are repeatedly found in the (social) media.
Why do biodegradable plastics not break down into microplastics?
The breakdown of plastics into microplastics is fundamentally different from biological degradation. Microplastics are created when plastics physically break down. This means that larger plastic parts are reduced to smaller and smaller particles due to external influences such as pressure, radiation and temperature. However, the chemical structure, i.e. the connection between the molecules, remains unchanged. Biodegradable plastics, on the other hand, are chemically decomposed. Accordingly, the molecular structure is not preserved. Microorganisms help here by attacking the connections between the molecules and breaking them down into smaller and smaller components. At the end of this process, only raw materials such as carbon dioxide (CO 2 ), water (H 2 O) and minerals remain. So while microplastics do not dissolve but remain in the environment in the form of solid particles for decades, biodegradable plastics decompose without leaving any residue.
What is the difference between biodegradable and compostable?
Biodegradability , as described above, is not subject to a defined period of time. Therefore, even biodegradable plastics can become a problem for the environment. This happens when they degrade over a very long period of time, such as several years.
Compostability, on the other hand, refers to degradation under specified conditions over a certain period of time. A distinction is made here between industrial composting and classic garden compost. In industrial composting, the plastic must degrade into water, CO2 and minerals within 12 weeks at 60 °C. When the material is then sieved through a sieve with 2 millimeter openings, no more than 10% of the original amount may remain. In contrast, degradation in garden compost must take place within a year at less than 30 °C. This is also known as home compostable.
The compostability certificate does not rule out the possibility that the product to be composted contains fossil components. It may even contain small amounts of non-degradable ingredients. Many of the compostable coffee capsules are therefore not only based on renewable raw materials, but are mixed ("blended") with fossil components. This is the key difference between the rezemo wooden capsule and other coffee capsules on the market: the rezemo wooden coffee capsule contains 100% bio-based ingredients. For us at rezemo, transparency is a core element of our corporate philosophy - and this also applies to our material. You can read how best to dispose of our coffee capsules in our blog post on capsule disposal .
Why is the rezemo coffee capsule sustainable?
Compost is also characterized by its humus-forming and soil-improving effect. This is primarily achieved through larger biomass particles such as pieces of wood or other plant residues. They loosen the soil and provide nutrients. These positive effects cannot be achieved by composting pure bioplastics. This is because they do not contain any biomass in its original form.
The rezemo coffee capsule is made mainly of wood and therefore contains a lot of the "good" biomass. The wood is processed in the form of sawdust, which is embedded in a PLA matrix. The wood contained not only provides nutrients and supports the formation of humus. It also accelerates the decomposition process. The sawdust absorbs water shortly after the coffee is prepared, thus increasing the surface area for the microorganisms to attack. These are crucial for the subsequent decomposition. In addition, coffee grounds are often used as an effective fertilizer - thus making the coffee capsule an all-rounder.
Are you curious? Discover our exquisite coffee editions in our ecological rezemo coffee capsule!
SEE FOR YOURSELF - GO TO OUR SHOP[1] https://www.wwf.de/2019/juni/wuerden-sie-eine-kreditkarte-essen
[2] https://www.umweltbundesamt.de/themen/mikroplastik-in-kosmetika-was-ist-das
[3] https://www.greenpeace.de/sites/www.greenpeace.de/files/publications/s02031-greenpeace-report-plastik-kosmetik-oekotox-21070522.pdf
[4] https://www.bund.net/fileadmin/user_upload_bund/publikationen/chemie/chemie_plastikatlas_2019.pdf
*Trademark of a third party company that is not associated with rezemo GmbH
