Materials Plastics: A material with an image problem
Plastic doesn't have a good reputation, and there are plenty reasons for this. However, our everyday life today would be inconceivable without plastic. Is it too easy a thing to condemn the material?
Plastic has a serious image problem. It would take a very talented PR agency to deal with this problem and make plastics popular again. The criticism on plastics and the general environmental damage associated with it date back to the 1970s. In this decade, the first study was published that investigated the influence of plastic on marine life. Since then, it seems, the criticism has not ceased. In many cases, this criticism is justified. Who hasn't seen the pictures of beaches full of garbage, floating islands of trash in the sea and animals dying in the midst of plastic bags and packaging?
Microplastics: An invisible danger
Besides heaps of plastic garbage, the last years have seen another problem arising: Microplastics. These very small plastics particles are created when larger plastic parts fall apart. Moreover, microbeeds made of plastic are often part of cosmetics and cleaning products. Last but not least, our everyday life also produces microplastics. Washing fleece sweaters, for examples, leaves the smallest particles in the water. Rubber tyres are another source. Car manufacturers increasingly work on low-abrasion tyres in order to reduce the production of small plastic parts.
According to a study by the Global Marine and Polar Programme and the International Union for Conservation of Nature(IUCN), these tiny particles account for 15 to 31 percent of all plastic that is released into the ocean every year. Some 35 percent of these particles come from clothing and 28 percent from tyre wear. But why is microplastic so dangerous? In the meantime, researchers have shown that the particles are absorbed by cells, accumulate between cells and disrupt communication between cells. Even though there are no long-time studies on the effects on the human body yet, the accumulation of plastic in our bodies leaves a bad feeling. It is, however hardly preventable. Conventional filter systems have problems to fish the particles out of the water. People are therefore very likely to consume plastic with their food and drinks.
Some countries are starting to ban the use of microplastics, for example, in cosmetic products. Since 1 July, products containing microplastics are no longer allowed on the shelves in Sweden. The United States prohibited the production of cosmetics with microbeeds last year. Since July, such products can no longer be sold there, either. Starting next year, some pharmaceutics will also be affected. Great Britain is following on a similar path.
Where does the plastic waste come from?
However, these prohibitions only apply to the addition of microplastics to products. A large proportion of the particles found in oceans and other waters do not come from these products. They occur when larger plastic parts decompose. With plastic waste swimming everywhere in the sea, this is a huge problem. Where does this plastic waste in our seas come from? Is it tourists who leave sunscreen bottles and ice packs on the beach? Is it cruise ships and freighters that dispose of their garbage on the high seas? Unfortunately, it is not as easy as that. In fact, more than 80 percent of the waste in the sea comes from the land. This is shown in a report by Eunomia.
Ten rivers are responsible for most of the plastic waste in the oceans
According to this report, 12.2 million tons of plastic migrate into the oceans per year. Nine million tons come from the land and coasts. Beaches account for only five percent of this pollution. A study published last November in Environmental Science & Technology shows that ten rivers are primarily responsible for the pollution. For this purpose, a total of 57 rivers around the world were examined. The researchers behind the study were able to show that between 0.47 and 2.75 million tons of plastic find their ways across rivers into the oceans every year. Ten rivers are responsible for about 93 percent of these: Yangtze, Indus, Yellow, Hai, Nile, Ganges, Pearl, Amur, Niger and Mekong. Eight of these rivers are in Asia, two in Africa. The Yangtze, a 6,380-km-long river in China, is by itself said to be responsible for 1.5 million tons of plastic waste being washed into the ocean every year.
The garbage then spreads all over the seas. Even if many are familiar with the stories of floating garbage islands, not all the garbage remains on the surface. According to the German Federal Environment Agency, 70 percent of all waste in the sea (including waste that is not plastic) sinks to the bottom. Only 15 percent remains on the surface. Another 15 percent is washed up on beaches.
The Great Pacific Garbage Patch: 100 million tonnes of waste
But even the mere 15 percent on the surface cannot be neglected. The area of the North Pacific Vortex between North America and Asia, a sea drift current, is also known as the Great Pacific Garbage Patch. The size of the patch is difficult to determine because the boundaries are diffuse. Reports that claimed that the affected area is twice as large as Texas could not be proven. In reality, the patch is not really a kind of island that is so densely contaminated that one could walk on it. The density of garbage is just particularly high in that area. However, some researchers assume that the waste amounts to a total of 100 million tonnes.
Plastic is everywhere
Actually, the amount of plastic waste is not surprising. Plastic is everywhere. From the toothbrush to computer mice to ventilation slots, we are surrounded by plastic. And for a good reason. Plastic has conquered the world since its invention. The discovery of vulcanisation and rubber by Charles Goodyear was one of the greatest milestones of the 19th century. John Wesley Hyatt, who significantly improved the manufacturing process for the first thermoplastic, was looking for a replacement for ivory to produce billiard balls. He had the process patented in 1865.
Since then, plastic has spread into all areas of our lives. Compared to other materials, plastic has some major advantages. Unlike metal, some plastics are resistant to some acids and alkalis. Other plastics are also resistant to petrol and can therefore be used for the construction of fuel tanks. Because of this chemical resistance, plastic is a popular material in the manufacture of household and electrical appliances and toys.
Another great advantage of plastic is that it can be shaped into almost any shape with comparatively little effort. And it is this property that made the material so popular. In the 1950s and 1960s, plastic utensils conquered every household. The many possible colours and shapes made completely new designs possible. Thanks to the inexpensive production, everyone could afford items that would have been too expensive when made from conventional materials like metal, glass or wood.
A full house made of plastic?
One sign of how much the material was seen as the material of the future is a rather curious one: Monsanto built almost an entire plastic house in the 1950s. This house could be admired from 1957 to 1967 at Disneyland in California, USA, and was intended to demonstrate the changeability, stability and versatility of plastic. Some 435,000 visitors admired this “home of the future” before it was torn down again after 10 years – with some difficulties because the plastic was so stable.
However, the simple formability of the material is not only interesting for modern designs – complex shapes can also offer added value. For example, safety closures for drugs can actually only be implemented with plastic. The medical industry is probably the sector that benefits most from plastics. Here, too, costs can of course be saved, as plastic is cheaper than glass, for example. Additionally, most prostheses would not be conceivable without plastic, just like stents.
The risk of infection in clinics has also been reduced by using sterile plastic packaging and disposable products. The use of antimicrobial plastic prevents the spread of diseases. The material is able to stop or even kill bacteria. For example, plastic does not corrode and can therefore often be used longer than other materials. The shelf life of medicines can also be extended by plastic packaging.
What are the alternatives to plastic? And do they work?
Not everything that is made of plastic today has to be made of plastic. Not least because of the bad reputation of plastic, there is a trend back to previous materials. Consumers are afraid of toxic ingredients, such as plasticisers and stabilisers in plastic packaging, and thus are turning to glass, cardboard and aluminium again.
Glass, for example, is much more resource-saving. Instead of oil, glass is made of 75 percent sand. This quartz sand accounts for 12 percent of the earth's crust – a much better proportion than the resource of plastics, petroleum. Glass recycling is also very successful. Since 1970, energy consumption in glass production has fallen by 77 percent, not least thanks to the recycling of the material. But glass can also be easily cleaned and reused without shards.
However, one should not forget that glass is many times heavier than plastic. It cannot therefore be considered a full replacement. The energy and resources saved by using glass are very quickly levelled by the much greater transport effort. The production costs of glass are similar to those of tin cans. A positive environmental balance only really results with these forms of packaging if the products are used several times and do not have to be transported far. And even these forms of packaging cannot do without plastic: The lids and insides are very often covered with a plastic layer to protect the material and the contents.
Another point of contention about plastic alternatives is the ubiquitous everyday object shopping bag. As a customer at the supermarket checkout, you are often faced with the difficult decision: plastic or paper? The answer is extremely complex. Because here, too, the paper alternative is not as good as it seems. The energy required during production and the weight do not make the paper bag an ideal alternative, especially if it is not used several times. Moreover, the paper bag is only more resource-saving if it is made of recycled material.
And what about the so-called bioplastics?
This term refers to plastics made from renewable materials. Plastic from corn or sugar beet or even hemp sounds like a sensible alternative. But cultivated areas are also finite. When we use such products, we automatically lose resources elsewhere.
Biodegradable plastic may sound good at first, but here, too, there are problems. After all, biodegradable is a broad term and it does not mean the same as compostable. Researchers warn that even these materials do not decompose by themselves when thrown into the sea. Very often, certain circumstances are needed to degrade the material, for example, temperatures above 50°C or UV radiation. A biodegradable garbage bag that lands at the bottom of the sea or on the motorway embankment does not simply disappear by itself.
Plastics in Europe
Last but not least, plastic is viable for another reason: The industry is an important economic sector. The plastics industry in the EU28 member states had a turnover of almost 350 billion euros in 2016, and according to the European Plastics Association, the plastics industry ranks 7th in industrial value-added contribution.
Accordingly, the plastics industry makes a contribution that cannot be dispensed with. Nearly 30 billion euros were contributed to public finances and welfare in 2016. More than 1.5 million people in Europe are also personally affected: They are employed directly by companies in the sector.
Even though we face a huge problem with plastic garbage, we still can't do without it, that much is clear. Even the biggest plastic avoider is happy that he can be operated on under sterile conditions if need be. And we humans are creatures of comfort. Plastic has made our lives easier and it's not easy to get away from it. That may not be the right solution, either. Generally speaking, the material needs to be handled sensibly. Demonising it is just a quick fix. Not everyone can be expected to carry all their shopping home in glass and metal packaging. For many, products that are not packaged at all or packaged in recyclable materials, would not be affordable because transport and production are just too expensive.
The good news is that, in Europe, we seem to be doing a lot right in terms of recycling and incineration. European rivers flush comparatively little water into the sea and governments are making efforts to regulate disposable plastic. When plastic is thought of throughout its entire life cycle, one cannot ignore that it is an important resource that is not worthless even after its usage through recycling or incineration.