Plastic is one of the most common household items in Australia. Each house has plastic material, like bags, cutleries, containers, and whatnot. A study reports that in the financial year 2017-18, Australia consumed 3.4 million tonnes of plastic. But the alarming stat is that the recycling rate was only 9.4%.
The essential constituent of plastic is polyethene terephthalate (PET), which is non-biodegradable in our environment. No bacteria or microorganisms found in nature can decompose PET, due to which tonnes of plastic stays as it is in oceans and landfills. Plastic is one of the reasons for land pollution and water pollution.
Plastic harms the ocean life and the land animals equally. In the ocean, heaps of plastic garbage lie at the bottom, and aquatic animals either swallow them and die or entangle themselves in them. Plastic causes suffocation, indigestion, and entanglement of many marine species like whales, turtles, fishes, and seabirds each year.
Plastic waste on land harms both plants and animals. Stray animals swallow these plastic wastes and face suffocation and indigestion. The plastic wastes release harmful toxins in the soil and hinder the growth of plants and trees in it.
Bioplastic, also known as biodegradable plastic, acts as a substitute for petroleum plastic. The French scientist Maurice Lemoigne discovered bioplastics in 1926 and researched them. But it was only at the beginning of the 21st century that the general public knew about them.
The constituents of bioplastic have renewable materials, which make them biodegradable. Some of the biomass found in bioplastics are sugarcane, corn, tapioca, and other types of cellulose.
We can classify bioplastics into four categories based on how much time they take to break down:
All types of plastic are degradable, given the right time and environmental conditions. However, petroleum plastic will break into tiny fragments but will never go back to its components, so it continues to pollute the environment with its chemicals.
Bioplastic is biodegradable, which means that if left in the environment, the microorganisms in the soil will break the components of the bioplastic within a few months, and it will return to its natural form of cellulose and other constituents.
Bioplastics that the microorganisms can break down into biomass under specified conditions and time scales are called compostable. Not all bioplastics are compostable. Bioplastics have to meet the ASTM D6400 standards to get the label of compostable.
Some bioplastics have pro-oxidant in them, which is responsible for their degeneration. But there is still doubt whether the bioplastic completely breaks down or not.
Many countries are adopting a bioplastic environment to reduce the harmful effects of petroleum plastic. Bioplastics have many advantages over traditional plastic, and here are some of them:
Bioplastics may seem like a golden substitute for plastic, but they have their disadvantages which we cannot ignore:
Bioplastics may look like a better option than plastic, but there are some similarities between the two.
Bioplastics are biodegradable but not fully biodegradable. Bioplastics will break into millions of pieces but not return to their original state if left in the environment. Marine life or land animals can swallow these pieces and face the same problems if they would have eaten traditional plastic.
We need bio-reactors to break down bioplastics into their original condition, and bio-reactors are multi-million dollar industries. Otherwise, bioplastics need specific temperatures, pressure, and microorganisms to break down completely.
To put it simply, the natural biodegradation of bioplastics is extremely slow as they need complex conditions to degrade. Also, since bio-reactors are too costly to set up everywhere, most bioplastics end up in landfills and then into oceans. It makes them no different from the traditional plastic.
Bioplastics can have heavy metals, just like plastics, and can fragment if exposed to UV light and abrasion. These fragments can stay in the environment for as long as plastic does and contribute to polluting it.
We believe that a bioplastic environment will solve the global problem of plastic pollution, but this is not the whole truth. Bioplastics are as harmful to the environment as petroleum plastics are if not degraded correctly. We need to recycle petroleum plastics as much as possible and understand how to use bioplastics to save nature from their harmful effects.