Plastic pollution is a significant problem today which requires innovative and sustainable solutions. What was once considered a great invention for the world has now made our Earth sick. Plastic pollution isn't just a standalone threat; it comes with air pollution, water pollution, ocean pollution, chemical pollution, global warming, climate change, and other associated problems.
Many
living organisms get trapped in plastic ropes, nets, and similar items, leading
to their death. Some mistakenly consume these thinking they are food, which
poses health risks. Chemicals found in plastics
are now entering the food chain. Microplastics and nanoplastics, which are tiny
plastic particles, are ubiquitous—found in oceans, rivers, soil, and even
underground water—making them incredibly difficult to separate.
While
everyone acknowledges the dangers of plastic, resolving this issue requires
innovative solutions that involve science, technology, governments, and most
importantly, the collaboration of every individual. This article will discuss
innovative and sustainable solutions for plastic pollution in 2024.
How science and technology are providing solutions for plastic pollution?
1. Bioplastics: Focusing more or “true bioplastic”
Bioplastics
are those that can biodegrade in the natural environment over a short period of
time or are made from biobased sources, meaning natural polymers. The problem
with traditional plastics is that they do not biodegrade in the natural
environment, leading to their accumulation everywhere. Therefore, having
biodegradable plastics would solve many problems.
Biopolymers
include macromolecules such as cellulose, hemicellulose, proteins, starch,
pectin, and chitin, which are found in biobased or natural sources. Based on
these, there are three types of bioplastics:
- Fossil-based bioplastics with biodegradability: Plastics made from fossil fuels but are biodegradable, such as Polybutylene adipate terephthalate (PBAT).
- Biobased bioplastics with non-biodegradability: Plastics made from biobased sources but are not biodegradable, like bio-polyethylene. This is because it is derived from ethylene, which is then modified to have properties similar to synthetic polyethylene.
- Biobased bioplastics with biodegradability ("True bioplastics"): These are bioplastics made from natural materials and are biodegradable, such as polylactic acid. This is an excellent solution as it can be made from agricultural waste, animal waste such as feathers, hairs, bones, etc., and is biodegradable. True bioplastics offer a sustainable solution to plastic pollution.
2. Microbial Polyester
The use of
bacteria and microbes has been prevalent in human practices for centuries. From
fermenting milk to produce yogurt to using yeast to leaven bread, humans have
utilized microbes in various ways for a long time. Moreover, many chemical
compounds are now synthesized using these bacteria and microbes. It's important
to remember that even penicillin, the first antibiotic, was derived from
microbes.
Read: Causes and consequences of antibiotic resistance.
When
certain bacteria or microbes are provided with specific nutrient conditions,
they produce microbial polyesters. These microbial polyesters, such as
Polyhydroxyalkanoates (PHAs), can be utilized later either as polymers or for
the synthesis of new chemicals through various processes.
3. Mechanical and chemical plastic recycling
Recycling plastic waste involves sorting, washing, and reprocessing it for reuse. In mechanical recycling, no chemical bonds are broken in the plastic materials; instead, the plastic is simply melted and reshaped into new products.
Fact: Mechanical recycling reduces carbon dioxide emissions by 1.5 to 2.3 tons per ton of plastic recycled.
Chemical
recycling involves breaking chemical bonds in plastic waste through chemical
and biochemical reactions. This is then used to create new products. Chemical
recycling can be divided into two types: pyrolysis and conventional
gasification.
- Pyrolysis: In pyrolysis, long plastic polymers are converted into smaller hydrocarbon chains. This process occurs under oxygen-deficient conditions. The hydrocarbons obtained can be used as fuels, with diesel being one example. These hydrocarbons are obtained either in liquid or gaseous form and can be used to create new plastic products such as polyethylene and polypropylene.
- Gasification: In gasification, plastic waste is heated at high temperatures in the presence of a gasifying agent. Steam, oxygen, or air are commonly used as gasifying agents. The result of this process is synthesis gas (a mixture of hydrogen and carbon monoxide (CO + H2)) along with some hydrocarbons such as methane. This syngas can then be used to produce new plastic, new chemicals, or even generate electricity.
Both mechanical and chemical recycling, if
utilized effectively, can provide us with a sustainable solution. This is
because approximately 400 million tons of plastic are produced each year. The
challenge lies in the collection and transportation of plastic waste to
recycling sites. If implemented correctly, this can certainly contribute to
reducing plastic pollution.
4. Plastic upcycling
In plastic
recycling, plastic is typically recycled to be used as fuels, monomers, or
chemical feedstock. Upcycling is a bit different because it focuses on using
plastic waste in a more innovative manner. For example, turning chip packetsinto eyeglasses, as done by a Pune-based startup called Ashaya.
In
recycling, the quality of the product may remain the same or decrease compared
to the starting material. However, in upcycling, there is a focus on
maintaining or even improving the quality of the product.
5. Microbial Degradation
Microbial
biodegradation refers to the breakdown of plastic materials by microorganisms.
It is considered one of the best and most sustainable solutions for plastic
pollution if implemented with scientific innovation. However, so far, there
hasn't been significant innovation in this field, nor has there been great
success.
Let's
first understand why microbial biodegradation is considered sustainable.
Plastics mainly consist of amides, esters, ethers, and carbon-carbon bonds,
which are difficult to break down. Imagine there are microbes that can utilize
these molecules as food and completely degrade the plastic.
In the
past two decades, there has been considerable research on microbial degradation
of plastics such as polyethylene, polypropylene, polyvinyl chloride,
polystyrene, and polyethylene terephthalate. However, this process is often
slow, which remains a challenge. Bacteria such as Pseudomonas aeruginosa,
Bacillus spp., and Bacillus subtilis have been highlighted for their potential
in this area.
6. Depolymerization and repolymerization
Depolymerization
and repolymerization have been known to scientists for a long time, but in the
past decade, many groups have been actively working in this field. Converting
polymers back into their starting monomers is indeed a sustainable solution.
One
innovative technology for this purpose is hydrogenolysis, where the presence of
hydrogen and catalysts such as photocatalysts are used to convert polymers back
into their starting monomers. These monomers can then be repolymerized back
into plastic.
However,
the main challenge lies in collecting and sorting plastic waste for this
process because the plastic waste needs to consist of only one type of polymer.
7. Self-healing Plastics materials
In our
homes, we have many plastic products, including those that contain
microplastics and microbeads. However, many plastic products are discarded
solely due to breakage, such as chairs, tables, etc. Similarly, in our cars and
public transportation, there are plastic products that are discarded only
because they have broken.
In this
regard, self-healing materials provide a sustainable solution. Imagine a broken
chair that can mend itself with just a little heat, becoming just as strong as
it was originally. Or imagine it healing in natural conditions.
This is
what self-healing materials offer—a perfect innovative solution for plastic
pollution. Instead of discarding broken plastic, it can be used for a long
time.
8. Booms and clean-up boats
Booms are
floating layers of logs joined together and meant to trap surface detritus such
as plastics in water bodies.
They work
alongside clean-up boats equipped with nets and baskets to collect debris stuck
on the water's surface.
Booms exist in a variety of shapes and sizes to accommodate varied water conditions, but they cannot capture plastics beneath the surface.
9. Trash racks
Trash
racks are structures placed in bodies of water to collect solid garbage such as
plastic, twigs, and leaves carried by flowing water.
They are
made out of bars or grates positioned to enable water to pass through while
capturing larger debris, preventing it from flowing downstream.
Regular
cleaning is required to remove gathered material and prevent obstructions,
ensuring that the trash racks work effectively in cleaning up water pollution.
10. Sea bins
Sea bins
are specially designed floating bins that collect floating waste and
microplastics as small as 2 mm from the surface of freshwater and marine
systems.
Positioned
in calm waters near power sources like docks or marinas, sea bins draw in water
from the top and pass it through a filter bag inside, which selectively traps
waste while allowing water to flow back out.
Small and
large sea bins have been effectively deployed in various locations including
California, Oregon, Hawaii, and Texas, contributing to cleaner waterways.
11. Stormwater ponds
Stormwater runoff transports
a large number of plastic items and microplastics directly into rivers,
streams, lakes, and oceans.
Technologies like Stormwater
and Wastewater Filters and the In-line Litter Separator (ILLS) are employed to
prevent macroplastics from entering water bodies by trapping litter from
stormwater runoff in places like shopping areas.
Further these artificial
ponds function as centralised stormwater collecting and treatment stations.
Microplastics settle naturally in these ponds or are effectively removed by
adsorption, absorption, chemical, and biological methods.
Along with microplastics, larger plastic trash is being targeted for disposal. Furthermore, stormwater ponds serve an important role in treating a variety of other pollutants, such as oils, minerals, and toxic metals, helping to improve overall water quality.
12. Waterway litter traps
Bandalong
Litter Trap and SCG Litter Trap use floating devices to capture and guide
litter into traps, preventing macroplastics from flowing downstream and
polluting water bodies further.
13. Artificial intelligence and Robotics for pollution control and prevention
Detection aids such as the Malolo I unmanned aerial
robot and GPS trackers on ghost nets help to identify and mark marine waste for
eventual collection or tagging, making cleanup activities more efficient.
The CLEVER-Volume system uses sensors to validate
the amount of ship garbage reported, promoting proper waste management
practices and preventing macroplastic discharge into aquatic bodies.
Drones and robots like WasteShark and Jellyfishbot
use cutting-edge technology to collect floating waste from bodies of water. Mimicking the natural processes to come up with innovative technologies such as robots is also known as biomimicking which serves as sustainable solutions to a lot of problems.
Sand filters, such as the Barber Surf Rake and Barber Sand Man, remove debris from beaches with tractor-towed or walk-behind equipment.
What governments doing at international and national level?
Governments
at all levels—local, national, and international—are beginning to confront this
issue.
- Between 2000 and 2019, at least 28 international initiatives were developed to combat plastic pollution.
- The United Nations Environment Assembly (UNEA) has adopted several resolutions aimed at reducing marine plastic pollution.
- The G7 recognised marine pollution as a global concern in 2015, and in 2018 adopted the Ocean Plastics Charter, which outlines concrete objectives to decrease plastic waste in the ocean.
- In 2017, the G20 approved an Action Plan on Marine Litter.
- Governments around the world are gradually implementing strategies to combat single-use plastic bags and other macroplastics, primarily through regulatory restrictions.
- Several countries, including the United States, Canada, and the United Kingdom, have passed statewide restrictions on microbeads in cosmetics.
What are more approaches to solve the problem of plastic pollution?
A course
on plastic pollution should be made mandatory in our schools. Here, children
should understand the significance of plastic products, their proper usage, and
how to dispose of them correctly. Because we cannot remove plastic from our
lives. We need plastic in every small and big thing, whether it's just a pen or
a space station. But when students are taught about their proper disposal, it
will be a very good start.
People
should be educated about plastic through documentaries, movies, symposiums,
seminars, and conferences, covering every small village.
The
government should invest more in new innovations such as true bioplastics,
polymer upcycling, and artificial intelligence such as robotics, which are
sustainable and innovative ways to solve the plastic problem.
Of course,
at the individual level, we should try to replace plastic items as much as
possible, such as avoiding using plastic bags for packaging and opting for
cloth or jute bags instead. Reduce the use of plastic items or reuse them
whenever possible. For example, opt for refillable pens to avoid buying pens
repeatedly. And we should always have a sense of responsibility to live on our
Earth and keep it clean.
References:
Plastic pollution solutions:emerging technologies to prevent and collect marine plastic pollution
Bioplastics from Biopolymers: An Eco-Friendly and SustainableSolution of Plastic Pollution
Recent Progress in the Chemical Upcycling of PlasticWastes