/ 3 March 2017

Microplastics are a macro problem

Dr Holly Nel from Rhodes University explains the dangers of microplastics
Dr Holly Nel from Rhodes University explains the dangers of microplastics

Picture the gorgeous sandy beaches along our shores and South Africa’s unique protected marine areas, and imagine the beaches and the waves crashing onto them. If you look closely, what do you see? The waves are severely polluted with microplastics — thousands of tiny pieces of plastic no larger than a lentil. The protected marine areas are not as unspoiled as we’d like to believe!

Even if you go in search of pristine isolated beaches, it won’t help. Beaches and bays hundreds of kilometres away from a port city or a river mouth can be just as polluted as a beach only 10km away. The abundance of microplastics depends more on ocean currents than the distances from the sources of pollution.

This year at South Africa’s National Science Festival (Scifest Africa), Rhodes University’s Dr Holly Nel will present the lecture Microplastics, a “Macro” Problem, where she will use findings from her post-doctoral research to explore the macro impact of microplastics.

Nel measured the amount of microplastics found on the beaches and waters in the surf zone of 24 sites along the South African coast. The sites covered a large section of our shoreline, from Cape Vidal on the East Coast to Port Nolloth on the West Coast.

According to Nel, primary microplastics are pieces of plastic that have been manufactured to be less than 5mm long. In this category we have microbeads, tiny plastic spheres used as exfoliants in face wash, toothpaste, deodorant and just about any other beauty products on the shelves. This category includes nurdles: small plastic pellets that are melted down to create large plastic items. Secondary microplastics are the shredded fragments of larger plastic products that have been worn down into tiny pieces. This category includes fibres from carpets and garments that have been broken down in the washing process.

The minute particles are so small that they usually pass through water treatment plants and into streams, rivers and eventually the oceans. Though these microplastics are seldom noticed on our beautiful beaches, they are there, and they are dangerous.

Microplastics leak toxic chemicals that are added during the manufacturing process. They also attract toxins because they are made from oil and have a relatively large surface area for their size. The tiny particles are then consumed by mussels, fish and other marine life as they travel up the food chain, and very often end up on our plates. This means that we humans are increasingly consuming significant amounts of plastic without even knowing about it.

Nel says that the consequences of human consumption of microplastics are not yet fully understood, but that researchers are busy investigating this problem.

The scientific investigation of microplastics in the world’s oceans is relatively new, and Nel’s study is one of the first to research sites in the Southern Hemisphere. 

For this and more inspiring and educational experiences, lookout for the electronic programme available at www.scifest.org.za. Ticket bookings can be made at www.tickethut.co.za/scifes or for telephonic bookings contact 08600002004.

Scourge of the make-up counters

Dr Holly Nel dislikes plastic microbeads — the tiny plastic balls you often find in face-scrubs, liquid hand-cleaners and even toothpastes — because they are polluting our rivers and oceans, as well as threatening our health.

The little plastic balls are deliberately put in cosmetics and certain other products in order to bulk them up and create abrasive qualities.

The problem is that a large proportion of these plastic pollutants pass through sewage treatment plants and into rivers and oceans.

How can you avoid microbeads? Nel advises users to read the packaging and be especially careful with face-scrubs. Don’t buy products that contain plastic microbeads or polyethylene beads, and avoid products that contain polypropylene.

She says that an environmentally aware consumer can find many natural scrubs to choose from and she has made her own scrubs, which are just as effective as the commercialised products.

The US and several European countries have already taken steps to ban the use of microbeads in cosmetic products sold in stores. South Africa’s green news portal, Green Times, is part of a local campaign to have microbeads banned in this country. For more information on the campaign, visit: http://thegreentimes.co.za/5-gyres-and-the-ban-on-…