In the debate about biodegradable plastics, there is a view that if degraded plastics cannot be composted, their impact on the environment is not much different from traditional plastics.
There is a consensus on the fact that even if degraded plastics are thrown into the environment, the degradation time is still much shorter than that of traditional plastics, but don't forget the consideration of microplastics. If all that is required is to disintegrate the plastic into a state invisible to the naked eye, then the initial photo-oxygen degradation is sufficient to do so.
A non-negligible contribution of biodegradable plastic is that it does not generate permanent secondary microplastics when degrading, which can greatly reduce the accumulation of microplastics in the natural environment.
Microplastics and their potential environmental and health effects have received increasing attention in recent years. All materials, including those derived from or produced by nature, eventually wear out or degrade. Just as plants eventually turn into humus, mountains and rocks are ground down to the size of sand or smaller over the course of centuries. The same goes for man-made materials, including synthetic polymers and plastics. The difference is that the latter are not easily incorporated into natural cycles, but persist in the environment for longer periods of time, since this is not their natural origin.
Given the environmental and human health hazards these microplastics pose, biodegradable plastics and polymers are gaining importance as a potential solution.
1.No permanent secondary microplastics
Although biodegradable and compostable plastics, like all solid materials, produce small particles (including microplastics) through wear and tear during use, they differ from the persistent particulates produced by traditional non-biodegradable materials, which instead Biodegradable.
The advantage of biodegradable polymers is that they do not erode into permanent secondary microplastics as they degrade, since most natural environments are inhabited by microorganisms capable of metabolizing these polymers. Therefore, the residence time of biodegradable polymers is much shorter than that of conventional plastic materials. In this way, biodegradable plastics help to minimize environmental impact and reduce the accumulation of microplastics in different environmental habitats.
2. Reduce Microplastics in Organic Composting
Industrial compostable plastics can significantly reduce the amount of persistent, non-biodegradable microplastics in organic compost, thereby reducing the amount of microplastics leaking into the environment with composting.
Composting from separately collected bio-waste, such as kitchen waste, is increasingly contaminated with (micro)plastics derived from traditional plastic impurities, which are mistakenly disposed of together with bio-waste.
Industrial compostable plastics help separate more organic waste and divert more biowaste for organic recycling. At the same time, they help reduce the contamination of biological waste from conventional plastics and ultimately reduce microplastics from conventional fossil polymers in composting.
Bioplastic products certified for industrial compostability are fully biodegradable, they are metabolized into CO2, H2O and biomass and decompose in less than 12 weeks, according to recognised standards such as EN 1343210. In this case, breaking down and resulting in smaller particles is a necessary part of the overall biodegradation process and should not be confused with persistent microplastics that remain in the final compost.
Even in the case of suboptimal composting, the process of biodegradation into smaller particles does not stop there, but continues in the soil.
3. Reduce microplastics in farmland
Soil biodegradable mulch helps stop the leakage and accumulation of persistent microplastics in the soil. Soil biodegradable mulch can reduce microplastics in agricultural soils, as described by composting.
European Standard EN 17033 specifies requirements for the biodegradation of mulch films used in agriculture and horticulture. They include biodegradation in less than two years, comprehensive ecotoxicity testing that considers all relevant exposure routes, and clear best practice guidelines.
Unlike traditional PE mulch, which can cause plastic particles to accumulate in the soil - even after planting is stopped, the biodegradable film does not cause the accumulation of plastic particles in the soil.
4. Reduce plastic microbead pollution
Plastic microbeads, usually refers to plastic particles with a diameter of less than 2mm, are a type of microplastics and are a major carrier of pollution.
An important source of microplastics is the personal care products that people use on a daily basis, such as scrubs, cleansers, body washes, toothpaste and cosmetics. Biodegradable alternatives to persistent microplastics that are intentionally added to cosmetics.
Many countries, including my country, have implemented bans on plastic microbeads, but there are some areas that need to use these plastic microbeads.
Biodegradable polymers offer a better solution in applications where the intentional addition of microplastics, or so-called microbeads, is required, such as in certain cosmetic products that use microplastics as fillers, exfoliating particles or emulsifiers.
Some biopolymers have been used as replacements for these traditional microplastics that accumulate and persist in the environment, as more and more countries around the world ban the use of intentionally added microplastics made from non-biodegradable materials. Many cosmetic companies choose to remove or replace plastic microbeads in their products with biodegradable solutions.
Of course, the biodegradability of intentionally added microplastics should be tested under prevailing conditions in the environment where the particles are most likely to end up, such as soil, marine environments or fresh water.
