Biodegradable Materials

We explain what biodegradable materials are, with examples. Also, how degradation and biodegradation are different.

What are biodegradable materials?

Biodegradable materials are those that the direct action of decomposer and detritophagous organisms can reduce it to its minimum essential components. In other words, they are those materials that can be decomposed or degraded by living beings. On the contrary, non-biodegradable materials are those that living beings cannot decompose.

Is called biodegradability the ability of a material or a product to be decomposed by the action of decomposing organisms, such as bacteria, insects, fungi and other beings that subsist by reducing organic matter into its fundamental components.

These organisms and microorganisms devour and decompose organic matter in the bodies of living beings, thus allowing their nutrients to return to the soil and feed plants. This perpetuates the ecological circuit of transmission of matter and energy.

These concepts are fundamental when thinking about waste pollution, since biodegradable waste does not hinder (or does so to a much lesser extent) the circuit of nature. They can be assimilated more or less quickly by it.

On the contrary, non-biodegradable waste remains in the ecosystem for long periods of time, since decomposers cannot reduce it and its degradation depends solely on the action of the elements and physical forces, such as heat, rain, erosion or oxidation.

Degradation and biodegradation

All matter that exists is subject to the action of naturewhether due to the action of other living beings or natural elements and forces, and in all cases it ends up deteriorating, losing its shape and decomposing into its constituent elements. This is what happens, for example, with natural waste, with much of the garbage we produce and eventually with the bodies of living beings themselves.

However, not all matter decomposes in the same way.. When this occurs thanks to the action of microorganisms, insects, fungi and other detritus-phagous beings, it is known as biodegradation; and When it occurs due to the action of sunlight, temperature changes, wind and other natural forces, it is known as degradation.. Seen this way, it could be stated that biodegradation is a specialized type of degradation.

These processes usually take some time, depending on the conditions in which the matter is found. Thus, it is possible that the process is faster if it is subjected to more simultaneous degradation dynamics.

Some examples of the time it takes to degrade certain objects are:

• A banana or plantain peel: between 2 and 10 days.
• A cotton scarf: between 1 and 5 months.
• A sheet of paper: between 2 and 5 months.
• A fresh orange: about 6 months.
• A cigarette butt: between 1 and 2 years.
• One gum consumed: about 5 years.
• A wooden stake: between 2 and 3 years.
• An animal bone: between 10 and 15 years.

Types of biodegradation

There are two basic forms of biodegradation: aerobic (in the presence of oxygen) and anaerobic (in the absence of oxygen).

• Aerobic biodegradation. It occurs thanks to the action of various bacterial and fungal microorganisms, which take advantage of the water, carbon dioxide and oxygen present in the atmosphere to produce chemical reactions that reduce the long protein chains into simpler compounds that generate energy, that is, , through digestion processes.
• Anaerobic biodegradation. It occurs thanks to various bacterial-type microorganisms, which degrade the matter and release various organic substances, such as methane (CH₄), carbon dioxide (CO₂) and hydrogen sulfide (H₂S), throughout four stages: hydrolysis (breakdown of larger molecules), acidogenesis (generation of fatty acids), acetogenesis (transformation of acids into ketones) and methanogenesis (release of organic gases).

Importance of biodegradation

Biodegradation is a key process for sustaining life and conserving energy and matter in the ecological circuit. This means that Thanks to it, the materials that make up the body of living beings can be recovered and reintroduced into the food chain. once they have died.

Otherwise, a significant amount of organic matter would be continually lost, or it would depend exclusively on the action of the elements and natural forces to do so, which in some cases can take a long time. This is precisely what happens with non-biodegradable materials, such as plastic: they remain in the ecosystem for a long time, causing sustained damage while waiting for the action of the elements to decompose it.

So, Biodegradation can be thought of as nature's ability to absorb discarded material and ensure that nothing is lost.: all organic matter is eventually consumed by life itself, providing sustenance to certain types of beings.

Examples of biodegradable matter

Some examples of biodegradable matter are:

• The natural waste of living beingssuch as tree leaves and branches, animal hair, flakes of dead skin or animal excretions.
• spoiled foodsuch as fruits, cereals, meats, dairy products, among others.
• The textiles made from natural fibers (not synthetic, that is, not plastic).
• Derivatives of natural fiberssuch as paper, cardboard, ropes and non-chemically treated wood.
• Dairy productsremains of infusions or coffee, egg shells.
• The bodies of the dead animals and plants.

Continue with: The three Rs

References

• “Biodegradability” on Wikipedia.
• “Biodegradable waste” at the National University of Colombia.
• “Biodegradable products, what are they and what are they for?” at Nestle.
• “What 'Biodegradable' really means” in Small Businesses.