This is a topic that I would like to clarify because right now we have a boom of new materials in the market, such as the famous bioplastics. But are they really better than plastic?
To begin with, bioplastics are all those plastics that derive from plant products (corn, soy, potato starch) and not fossil fuels. Well, this is already a beginning, since we know that oil is a scarce resource and its extraction makes a big environmental impact.
So far, we have these problems with the plastic of fuel origins:
- It remains in the environment for a very long time (hundreds of years) contaminating waters and, thus, endangering animals.
- The extraction of the raw material (oil) implies a huge environmental impact, which can affect the natural environment, contaminating soil and water, and affecting the health of the animals and people that are nearby .
- Recycling depends on the type of plastic, its additives components and on whether the country has the means to recycle it.
- When it is not possible to recycle it, it is usual to incinerate it, releasing greenhouse gases.
Types of bioplastics
However, many companies and institutions are investigating the option of using a more eco-friendly substitute. Therefore, these famous bioplastics could be classified into 3 groups:
1. Vegetable Derivatives (Or partially)
They are the basis for durable plastics, such as polyethylene (PE), PET… On the one hand it has the advantage they reduce their carbon footprint, because these absorbe CO2 while growing .
But, on the other hand, if we use them to produce disposable materials that produce CO2 when recycling or incinerating, we are not really making any better. It kind of reduces a bit the carbon footprint of plastics production, but they still have the same problem as conventional ones: recycling them will depend on the country and the type of plastic.
2. Plastics with biological and biodegradable composition.
These are a new generation of plastics which composition is generally based on starch and are biodegradable. Compared to the previous one, these plastics have a lower carbon footprint and can be biodegraded.
But … it means that we are going to grow food or use raw materials that we could eat to produce plastics. This group would only make sense if we use organic waste that is not suitable for human consumption, otherwise we are promoting even more the monoculture system and the inadequate use of resources.
3. Plastics that are based on fossil fuels and are biodegradable.
It is a bit the mixture of the current ones with an improvement of biodegradability, but its production is still scarce and it is a future resource. In addition, we return to the issue of using oil and its environmental impact.
To give you some examples, these two biodegradable bioplastics that exist already:
- Polylactic acid: Polylactic acid or polyacid lactic acid (PLA) is a polymer that is used to make packaging, but is also biodegradable. It is obtained from corn starch, or cassava or manioc, or sugar cane (rest of the world). Usually used for packaging.
- Polyhydroxybutyrate (PHB): PHB is produced by certain microorganisms as a carbon assimilation product. An American company had developed the material in the pilot plant stage but the interest faded when it was found that the cost of the material was too high. It can be used in packaging material.
All this sounds great but I still have some questions:
How long does it take to degrade?
Well, those that are biodegradable take from 1 month to 2 years. In addition they are only used to pack products (single-use plastic). In the moment hey can’t be used for anything else, which greatly reduces their possible uses.
And, do all bioplastics biodegrade?
No, and that is the problem, since only those biodegradable and with a very specific composition have this characteristic. Regarding the rest of bioplastics, the degradation has the same problem as any other plastic: they are fragmented you have forming microplastics.
Then, what is the conclusion?
Well, it really is very complex, in certain aspects there is no way to eliminate plastic: medicine, transport, food packaging …
For me, the real and final solution is the same as always: reduce. If we reduce the amount of useless plastic in our lives living zero waste, we could bet on materials that are a bit more sustainable. If the plastic is used only for the strictly necessary and all countries do their part for an efficient recycling, you could bet on biodegradable bioplastics, but until then … we will have to demand a social change and put our part in the reduction of this material on our own.
- Brown, Valerie J. (Febrero de 2007). «Industry Issues: Putting the Heat on Gas». Environmental Health Perspectives (US National Institute of Environmental Health Sciences) 115 (2): A76.
- «Chemicals Used in Hydraulic Fracturing»(PDF). Committee on Energy and Commerce U.S. House of Representatives. 18 de abril de 2011. p. ?. Archivado desde el original el 21 de julio de 2011.
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