In recent years, the use of biodegradable plastic bags and compostable packaging to reduce plastic waste has been widely praised and supported globally. In many countries, the use biodegradable plastic bags has become a movement that actively affects the daily habit of shopping and using plastic bags.
But have you correctly understood biodegradable plastic bags? How much do you know about them?
1. What are biodegradable plastic bags?
In the current market, there are types of so-called "biodegradable plastic bags". In particular, there are bio-plastic bags, biodegradable plastic bags, compostable plastic bags, bio-compostable bagss, environmental friendly compostable plastic bags, self-decompose plastic bags. They are all advertised to be able to self decompose and limit plastic waste that negatively impact the environment.
But can they actually self decompose? Are they good for the environment
The answer is not as straightforward as you might expect. Not quite is a simple way to put it. There is no plastic bag that can completely self biodegradable. In addition, as long as there is the word "bio", it does not necessarily means that it is eco-friendly.
In theory, there is no material that can completely decompose on its own. In order for the decomposition process to occur, there has to be external factors such as bio-organism, bacteria, and environmental factors such as lighting, temperature, and moisture. These factors will actively alter the structure of the material and break it down, causing the overall material to be decomposed. Therefore, using the word self-decompose for products is inaccurate. To further clarify, we will go over 3 following concepts:
- Biodegradable process: is a process of a material decomposed by living organism into water, Carbon Dioxide, and into organic particles in the natural environment.
- Bio-plastic bags: are bags made from natural materials such as corn starch, potatoes, flax. These bags can be either biodegradable or not. In principle, these bags are no different from the traditional plastic bags.
- Biodegradable plastic bag: are plastic bags made from natural sources such as PLA, PHA hoặc gốc dầu mỏ như PBS, PCL, PBAT. They offer the ability to be decomposed into water and Carbon Dioxide, and biological contents in a short period of time. Depending on the biodegradability of the plastic bags, bio-plastic bags can be divided into 2 categories:
- Bio-plastic bags with biodegradability: Plastic bags made from PLA and PHA.
- Bio-plastic bags without biodegradability: Plastic bags made from biobased PE (HDPLE, LDPE), PET, PP.
Therefore, to truly protect the environment, you have to specifically look for bio-plastic bags with biodegradability.
2. Advantages of biodegradable plastic bags
Biodegradable plastic bags are highly advantageous comparing to traditional plastic bags.
- Health safety:: Since the biodegradable plastic bags are made from natural materials, they can help to prevent the exposure to highly toxic substances such as BPA, phthalates. Furthermore, unlike traditional plastic bags, which require burning, biodegradable plastic bags can safely decompose when burried underground using composting process. Without the burning process, the exposure to cancer and sickness inducing substances such as dioxin, furan are eliminated.
- Eco-friendly: As the biodegradable plastic bags can be completely decomposed into its biological form, it does not leave any toxic residue in the environment. In addition, the composting process can produce fertiliser that can be used in farming as well as forest restoration.
Quick decomposition: In favorable conditions, these biodegradable plastic bags can be decomposed in a short time, ranging from months to couple of years. When taken into consider with the 100 to 500 years decomposition time of traditional plastic bags, the decomposition time of biodegradable plastic bags are significantly shorter.
3. How to correctly look for biodegradable plastic bags?
There are certain criterias that can be utilised to pick out the biodegradable plastic bags that are truly eco-friendly:
1. Feel the bags
Feeling the products or physically examine the products is the first way that you can determine whether a bag is a biodegradable plastic bag.
- Touch, smell: Biodegradable plastic bags are often soft and smooth to the touch. In addition, the film layers will be thin and the color will not be as vibrant. If you closely smell the bag, it will have a starchy smell.
Burn: In the case you have obtained a sample of the bag, you can test it by burning it. If the bag easily catch fire and does not have any distinct smell, then it is completely biodegradable. Otherwise, if the bag shrink and has a over-burnt smell or distinct smell, then it is not completely biodegradable.
2. In the case you cannot physically examine the bags, read the label
To avoid incorrectly labeled biodegradable plastic bags, it is necessary to have a closer look at the label that indicated which materials the bag is consisted of.
- Don't: Don't pick bags made from materials that lack biodegradability such as PP, PE, HDPE, LDPE…
- Do: Bags indicated to be made from materials such as PLA, PBAT, PHA, PCL… If the bags are indicated with the following, they are certainly biodegradable plastic bags:
- TUV OK compost INDUSTRIAL: The bags can be safely biodegraded and decomposed in an industrial composting setting.
- TUV OK compost HOME: The bags can be safely biodegraded and decomposed in household composting setting.
- (BPI) Biodegradable Product Institute Compostable: The bags can be safely biodegraded and decomposed in specific institute composting setting.
- DIN CERTCO compostable: The bags can be safely biodegraded and decomposed in an industrial composting setting.
- TUV OK biodegradable SOIL: The bags can be safely biodegraded and decomposed underground.
- TUV OK biodegradable WATER: The bags can be safely biodegraded and decomposed in water.