Conventional platics
We all know plastic bags take up to 1000 years to decay. Many people want to switchover to biodegradable plastics. While choosing/procuring biodegradable plastic bags we get really confused with varied terms and standards prevailing in the world and mostly ending up with fake ones.
For an example, few manufacturers in the market are showing ASTM D 3826, ASTM D 5200 and ASTM D 5510 standards test reports as Standards for Biodegradability. None of these standards determine biodegradability of a plastic i.e., the actual microbial activity taking place. All the standards mentioned are Not Real Standards for measuring Biodegradability. These standards are determining degradation at the endpoint using Tensile Test, UV exposure and Oxidatively and not measuring microbial activity. All these standard are appropriate standards for measuring degradation due to some induced methods and result in fragmentation or brittle. Plastics which are qualified as per these standards are to be called as “Degradable Plastics” only. They should not be called as “Biodegradable Plastics”. There is a huge difference between Degradable Plastic and Biodegradable Plastic. To determine any plastic as biodegradable plastic, biological degradation (microbial activity taking place) on the plastic should be proved.
DEGRADABLE PLASTICS: Very Bad for the environment. They are not Biodegradable plastics. They photo degrade in the presence of UV radiation/oxo-degrade in the presence of oxygen. Means, they will degrade into bits and pieces in few years. No (biological degradation) microbial activity is proved in these plastics. They are more dangerous than the normal plastics as they spread easily and contaminate soil and waterways.
BIODEGRADBLE PLASTICS: The Carbon product is taken inside the microbial cell and biologically oxidized to C02 which releases energy that is utilized by the microorganism for its life processes to multiply growth. Biodegradability is measured only in composting conditions by measuring C02
How to understand and choose a genuine and Best Biodegradable Plastic? :
There are many confusing terms like biodegradable, compostable, degradable, oxo-degradable, oxo- biodegradable, photo degradable, etc. Similarly many standards (specified in numbers) are used in the world to determine Biodegradable Plastics. Among them only EN, ISO and ASTM standards are universally accepted standards.
We can easily get rid of all these confusing terms and numbers by using the following conditions. Fortunately all the standards in the world follow almost same parameters. They are as follows:
- Test for 180 days should be done in an approved lab.
- C02 evolution from plastic should be achieved at least 90% in 180 days.
- Heavy Metal/Toxic substances should be tested and it should not exceed the prescribed limit as per the same standards.
If anyone has tested their plastic and proves above conditions in any BIS approved lab in India, their plastics are genuinely biodegradable plastic. Test done for less than 180 days does not qualify as biodegradable plastic. Extrapolation is not permitted in it. When it comes to saving the environment, there should not be any compromise in prescribing standards
What biodegradable plastics are allowed in India?
Ministry of Environment and Forest prescribed “Plastic Waste (Management and Handling) Rules” on 4th Feb 2011. Please see Rule 5 (f) and Rule 7.
As per the rules bags should qualify as per ISO Standards of ISO 17088 / ISO 14851 TO 14855, 15985, 16929, 17556 and 20200 only. Only ISO 17088 and 14855 are in practice. ASTM and EN standards are not mentioned in the rules, hence not allowed in India.
Points for Procurement of Biodegradable Plastics in India can be as follows:
- As per the standards of ISO 17088/ISO 14855
- The supplier has to submit test certificate for having acquired Test certificates from a BIS approved laboratories for (a) achieving 90% biodegradation in 180 days and (b) Toxic substances less than the prescribed limits.
Hope we could explain in a very simple way.