Why are plastics called non-biodegradable? (7 classes of plastics) 

In this article, it shall be known why plastics are called non-biodegradable. Other covered aspects will be: 

  • What are plastics?
  • What are the types of plastics?
  • What are the effects of plastics?
  • Are all plastics harmful?
  • What is biodegradation?
  • Are plastics biodegradable or non-biodegradable?
  • FAQs

Why are plastics called non-biodegradable?

Plastics are called non-biodegradable because most plastics are made from fossil fuel derivatives and synthetic chemicals that make them non-biodegradable. 

Biodegradation is an important parameter to ensure that waste is not accumulated so that environmental anomalies are deterred and avoided. 

Plastics made from fossil fuel derivatives are not biodegradable. Plastics made from natural sources such as plants or animal sperm are biodegradable and may degrade in three years. 

Plastics are synthetic polymers that are extensively used in the consumer marketplace. There are seven categories of plastics that are segregated based on qualities and applications.

What are plastics?

Plastics are a type of polymer. A polymer is a substance or material that is made from repeating units. The repeating units are termed monomers. 

The monomers are chemically bonded to make a polymer. Common examples of polymers may include DNA, RNA or proteins. 

When it comes to polymers, there is a general classification. This classification is based on the naturality or synthetics of the polymers. 

A polymer is naturally occurring and does not need to be devised or synthesised, it is termed a natural polymer. However, if a polymer is not occurring in nature but rather is made in the labs, then the polymers are regarded as synthetic polymers. 

Examples of natural polymers include DNA, RNA, Proteins et cetera. As per the examples of synthetic polymers, plastics are the most common examples of synthetic polymers. 

As per the type of polymers, it is generally seen that the effects of synthetic polymers are greater and more fervent on life and the environment as compared to natural polymers. 

This is mainly because synthetic polymers are derived from products that are derived from fossil fuel derivatives. Such derivatives are known to cause environmental anomalies such as emissions of greenhouse gases and global warming. A detailed account of these effects will be covered in the next section of the article. 

What are the types of plastics? (7 classes) 

Plastics are found everywhere. Most commercial consumer products make use of plastics because of the utilitarian value given off by plastics. 

It is argued that the common use of plastics is because of the fact that plastics are cheap yet this does not affect the usability factor rendered by plastics. 

Owing to the diverse use and applications of plastics, there are seven categories of plastics. The categories are there so that plastics may be segregated and studied well. The categories of plastics are: 

  • PET 
  • HDPE
  • LDPE
  • PP
  • PVC
  • PS
  • Other

These categories link to the discrete use and qualities of plastics. You may wonder what is the last category of plastics. This category is reserved for new types of plastics. 

Common examples of the seventh category can be DNA plastics and bioplastics. These will also be detailed in the coming sections of the article.

Among the remaining categories, it is generally regarded that HDPE, PP, and PET are relatively safer and do not make use of harmful chemicals and materials. 

However, this is not the case for the remaining categories. There may be harmful chemicals or elements used to make such plastics (for example LDPE). An example can be BPA.

Bisphenol-A is an organic compound which is thought to disrupt hormones and cause other medical complications such as cancer or irritations. 

Among the types of plastics, the seventh category is regarded as the safest and the least damaging to the environment. This is mainly because plastics in the seventh category are made from natural, plant-based materials rather than fossil fuel derivatives. 

What are the effects of plastic?

The following are the impacts caused by conventional plastics on life and the environment. There are 7 categories of plastics. 6 of them are based on fossil fuels derivatives and therefore, will have a significant impact. These can be: 

  • Global warming
  • Loss of life
  • Species endangerment
  • Unprecedented weather patterns
  • Pollution
  • Disruption of ecosystems 
  • Infiltrations into the food chains 
  • Leaching
  • Eutrophication 

This is mainly because plastics are made from products that are derived from fossil fuels. When fossil fuels are used, it results in the increased emission of greenhouse gases. 

Greenhouse gases are gases such as carbon dioxide, carbon monoxide, methane et cetera. These gases entrap the sun’s energy and lead to a phenomenon known as global warming. 

Global warming leads to other environmental issues such as increased global temperatures, effects on life, deforestation, melting of glaciers, increased melting of glaciers, increased flooding, and unprecedented weather conditions. 

The impacts of plastics are not only limited to the environment but are also manifested in humans. Common complications that arise as a result of plastic use and exposure include: 

  • Organ damage 
  • Damage to skin 
  • Cancer 
  • Eye diseases
  • Hormonal disruption 
  • Neuro Complications 
  • Developmental issues
  • Damage to the foetus 
  • Heart & lung diseases 

Are all plastics harmful?

No, not all plastics are that harmful to the environment and human health. The seventh category of plastics includes bioplastics and DNA plastics.

Bioplastics are made from plant-based materials such as corn starch, sugarcane, sugar beets, mushrooms et cetera.

DNA plastics are made from DNA or biosources such as salmon sperm cells. 

These plastics are made from natural sources and are often renewable. Therefore, there are very minimal impacts of such plastics on health and the environment. 

To further build up our stance, let us explore some benefits and advantages exhibited by the use of DNA plastics

Plastics made from DNA come along with a number of environmental and social benefits. These are: 

  • DNA plastic takes up very less amount of energy to make
  • DNA plastic does not depend on fossil fuel derivatives
  • DNA plastic can easily be degraded by enzymes
  • DNA plastic can also be recycled with great efficiency 
  • DNA plastic does not add to waste generation and accumulation
  • DNA plastic is made from bio-renewable resources
  • DNA plastic may lead to 97% fewer carbon emissions

These are some of the reasons why it is so important to go for biodegradable and bio-renewable resources of plastics because the current waste generation caused by plastics is already beyond 90 million tons. 

Other than the issue of waste generation, conventional plastic leads to a fervent amount of carbon emissions which can be reduced by opting for natural sources instead of depending on fossil fuel derivatives. 

These bioplastics may be used for a number of applications such as the making of plastic cups et cetera. Since there are natural and biological materials involved, there are no known side effects of bioplastics.

What is biodegradation?

Have you ever seen rotten fruits or vegetables? If you have, then you can make an educated guess of what biodegradability is. 

It is the breakdown of waste into simpler substances by various drivers of life. Microbes, bacteria, fungi, algae, and decomposers are the most common drivers that cause biodegradation. 

Other important elements that are essential to the equation of biodegradability are aeration, sunlight, temperature, pressure, and other external conditions. 

Recent approaches to biodegradation have also enabled scientists to employ lab-based enzymes and chemicals to achieve the process of biodegradation. 

You may wonder why biodegradation is essential. It is important because it leads to reduced waste generation and accumulation. 

This ensures that life and the environment are saved from the harmful and degradative effects of biodegradation. This will also enable better waste management because if waste management is facilitated, there will be decreased consumption of energy and resources. 

Based on biodegradability, waste may be divided into two categories. These are 

  • Biodegradable waste
  • Non-biodegradable waste 

Examples of biodegradable waste include crops, plants, dead animals, manure, sewage, bioplastics, and natural fabrics. These may degrade in some days or some months. 

Examples of non-biodegradable waste may include synthetic plastics, epoxies, synthetic dyes, and synthetic fabrics like acrylic fabrics. These substances may remain in landfills for hundreds of years. 

For example, synthetic plastics may degrade in more than a thousand years while also causing other environmental problems such as global warming, weather anomalies et cetera. 

Are plastics biodegradable or nonbiodegradable?

Based on the studied literature, it is now possible to build a stance on the biodegradability of plastics. 

It is known that biodegradability is the breakdown by the action of microbes and enzymes. For a product to be biodegradable, it must be made and sourced from natural materials. 

We have discussed seven classes of plastics. It is known that the first six classes are made from fossil fuel derivatives. These are not biodegradable. 

However, bioplastics and DNA plastics from the seventh category are indeed biodegradable because these are made from bio-renewable sources as detailed in the previous sections. 

As per the degradation time, it is argued that non-biodegradable plastics may take many hundred years to degrade. For example, some plastics may take more than a thousand years to degrade. 

Whereas bioplastics may degrade readily. It is argued that bioplastics may degrade in nearly three years. This time may vary based on source and external conditions. 


It is concluded that plastics made from fossil fuel derivatives are not biodegradable. These plastics may take many hundreds of years to degrade. 

However, plastics made from natural sources such as plants or animal sperm are biodegradable and may degrade in three years. 

Biodegradation is an important parameter to ensure that waste is not accumulated so that environmental anomalies are deterred and avoided. 

Plastics are synthetic polymers that are extensively used in the consumer marketplace. There are seven categories of plastics that are segregated based on qualities and applications.

Frequently Asked Questions:  Why are plastics called non-biodegradable?

Can plastics be recycled?

Yes, plastics can be recycled. In fact, recycling is one the best solutions to deal with non-biodegradable plastics because the effects can be delayed in this way. 

What are the sources of bioplastics?

The common sources of bioplastics may include sugarcane, sugar beets, mushrooms, animals’ DNA, or mushrooms. 


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