Plastic rain is the new acid rain.

Plastic pollution is an urgent and global problem. Most of the environmental attention to date has been focussed on household and packaging waste. But scientists have found that tiny fragments known as microplastics make up significant amounts of ocean plastic pollution. Scientists have recently been scrambling to find solutions to deal with our growing microplastics problem.

This time, they turned to tiny bacteria for help.

Microbiologists at the Hong Kong Polytechnic University (PolyU) devised a sustainable way to remove polluting microplastics from the environment.

Their partners in crime are bacteria called Pseudomonas aeruginosa. Capable of grouping microplastics floating around in wastewater, these microbe nets trap microplastics and sink them. The plastic blobs can then be disposed of or recycled.

Other research efforts include exploring different novel materials as filters to remove microplastics before they reach large water bodies. Nanocellulose structures are highly effective in capturing extremely small microparticles that our eyes can’t see. 

Researchers at the VTT Technical Research Centre of Finland envision that these inexpensive components could be installed directly at the point of microplastic generation. This way, the pesky particles won’t be able to make it to important waterways, where removal would be many times tougher.

But wait… How are microplastics different from the ubiquitous plastic products we use daily?

An invisible enemy.

We have seen horrific posts related to plastic waste circulating the web. While these dangers are visible to the naked eye, some are left undetected until fairly recently – microplastics

With sizes ranging from as small as one-tenth the width of human hair, to twice the size of fine beach sand, these microparticles are so small that they can be carried by the wind.

Recent studies highlight the seriousness of this issue. 1000 metric tons – easily the weight of 120 million plastic bottles – rained on protected areas across western US. 84% of microplastics originate from road sources, while the rest come from agricultural dusts and oceans.

Illustration of how microplastics get into the atmosphere. Photo credits: Janice Brahney/PNAS

They come from anywhere you can imagine.

These invisible threats come from a variety of sources, some very surprising.

Plastic materials (think your bags and bottles) left out in the environment disintegrate gradually into smaller and smaller pieces. 

Even doing your laundry releases microplastics – tiny microfibres slough off your synthetic clothes and get flushed to wastewater treatment plants.

Researchers also accidentally discovered huge numbers of tiny microplastic specks in their plastic container while prepping their lunch.

Tyres driving over roads break down deposited plastic particles into finer microplastics, enabling them to be launched back into the atmosphere, just like how oceans recirculate microplastics.

One-way ticket around the globe.

What’s even more disconcerting is that microplastics can be transported to distant and pristine locations such as Antarctica, despite being so far away from actual sources of microplastics. 

This just shows that microplastics are already spiralling through Earth’s recirculation system. And because of their astounding chemical longevity, microplastics spend many years cycling through different circulatory systems such as air, land and sea, ultimately ending up somewhere far from where they came from. 

You could be taking in a deep breath of “fresh” air at Joshua Tree National Park, while tiny flakes of acrylic polymer – that could have come from someone’s laundry in Japan –  land imperceptibly on your nose.

Effects on humans still unclear.

Ingestion of microplastics by small creatures lead to blockages in their intestinal tract. The ingestic plastics could move up the food chain, leading to a plastic accumulation in organisms at the top of the food chain, akin to heavy metal bio-accumulation

Some sea creatures exposed to microplastics even displayed difficulties in growing, severely affecting their ability to survive.

You’re also likely to be eating microplastics every day without even noticing it. 

Microplastics were revealed in the placentas of unborn babies just a couple of months ago, most probably shed when shaking up plastic baby bottles filled with hot baby formula.

Assuming that the microplastics would somehow hamper foetal growth and cause long-term damage to its immune system, the researchers have yet to determine their exact health impacts on the human body. 

But it’s reasonable to assume that having tiny bits of plastic lodged in your lungs or in your unborn child are hardly good things.

Eliminating microplastics requires global effort.

An overall picture on the consequences of microplastics to us and the ecosystem in general is still unclear. But such repercussions are inescapable in the immediate future. 

Returning to the pre-plastic era is unimaginable, unless we come up with materials as great as plastic, but not as environmentally upsetting.

Perhaps one of the most effective ways to end this microplastic scourge, aside from inventing innovative methods of removal, is to cut out single-use plastics.

Just like how we cast a dry spell on acid rain, we too, can put an end to this toxic microplastic cycle.

Main picture: Microplastic debris found on Depoe Bay, Oregon in January 2020. Photo credit: Andrew Selsky/Associated Press.

By Mitchell Lim

Mitchell Lim is the latest addition to DUG’s science communication department. Currently completing his PhD in Chemical Engineering, Mitch is an expert in the fields of catalysis and ultrasonics. Full-time science geek, part-time fitness junkie, Mitch is living proof that brains and brawn are not mutually exclusive. His mission is to make science more accessible to you, while dreaming of having access to Martian land someday.

DUG