20 January 2021

Microplastics: In and around you

By Associate Professor Moritz Müller

Plastic fantastic is all around us. We use it to keep our food warm and of course also in the form of facemasks and shields to help protect us from Covid. Global plastic production is expected to increase 40 percent by 2030, with hundreds of billions of dollars being invested in new plastic production plants worldwide.

Around half of the total plastic production is used for single-use packaging, but unfortunately, around 10-14 million tonnes of this end up in the oceans every year. This number is also expected to increase, nearly triple in fact, by 2040 to 29 million metric tons per year. The sheer amount of plastic pollution reaching the oceans day by day is incredible.

Southeast Asia contributes to the majority of this amount and even worse, in the region, Malaysia has the highest per capita plastic use with close to 17kg per person per year. This is scary on its own but there is another issue hidden from our eyes.

Larger plastic pieces gradually break down into so-called microplastics which are loosely defined as any polymer particle less than 5mm in size and insoluble in water. Sometimes they are also intentionally produced, for example, as exfoliation beads in the cosmetic industry, but more often they are secondary microplastics, broken down from larger plastic items.

These microplastics are resistant to biodegradation and can be ingested by small organisms in the water such as zooplankton and fish, escalating up the food chain, with likely harmful consequences for wildlife and humans. There are many studies highlighting a variety of potentially harmful effects when organisms ingest microplastics (and everything that lives on it).

In the end, they might end up in the fish on your plate. Fish (or other food for that matter) ‘seasoned’ with microplastics is not what one envisions to eat. Probably our most common food seasoning, table salt, has in fact been found to be heavily contaminated with microplastics. While it’s not certain yet if and what impact they might have on humans, it sure cannot be healthy to eat plastic on a daily basis – even if it’s just a little. Constant dripping wears away the stone.

To help reduce pollution, it is first necessary to know where microplastics are accumulating in the environment and how much is there. The extent and distribution of microplastics in Malaysia (and Southeast Asia) is, however, still almost completely unknown. A major obstacle is that detection and counting methods are challenging and expensive, requiring specialist equipment.

To help make the detection of microplastics more available to non-expert users or those without the financial backing to purchase the expensive machines, scientists have long aimed to develop a cheaper and quicker methodology.

Dr Andrew Mayes from the University of East Anglia in the UK is one of these scientists. His method uses a commonly available stain (Nile Red) that attaches to microplastics. Shining a blue light on it (much like the CSI detectives) then makes the stained plastic particles glow so brightly that you can picture them using a common DSLR.

Andrew has teamed up with partners in East Malaysia (Swinburne University of Technology Sarawak Campus) and West Malaysia (Universiti Malaysia Terengganu) with funding from the UK Global Research Translation Award, to form the Malaysian Microplastics Network or MyMip. It aims to enable more widespread and rapid monitoring of microplastics levels in Malaysia. In less than a year, the network has expanded to include 10 partner universities and non-governmental organisations.

One of the first projects to be carried out will be to look at our beautiful beaches to help identify potential hotspots and enable concerted policy and management efforts. There is much to be discovered and done but hopefully projects like this will make life on our beautiful planet a little more sustainable, and tastier.

Note for the interested: More information about the principles behind the method and the use of our Nile red microscope can be found in the MyMip Youtube channel (https://bit.ly/38RicXa)

Moritz Müller is an Associate Professor with the School of Chemical Engineering and Science at Swinburne University of Technology Sarawak Campus. He can be reached via email at mmueller@swinburne.edu.my.