Environmental Protection: The fate of plastic bags

The EU wants to drastically reduce the consumption of plastic bags and is hopeful that consumers will switch to more environmentally friendly alternatives. Until 27 November 2016, EU governments had to adopt measures to cut the consumption of plastic carrier bags and report them to the EU Commission as required by the EU Plastic Bag Directive. Germany has opted for a voluntary agreement. This sounds good, but there is more than one obstacle.

According to statistics, every EU citizen consumed exactly 198 plastic bags in 2010; of these 175 were single-use bags. Even though the average German uses only around 70 bags, the overall sum for a population of 82 million inhabitants comes to the sizeable figure of more than 6 billion bags. It is estimated that the worldwide annual use sums up to one trillion bags.

Plastic bags are often carelessly thrown away or not properly disposed of. In addition, it takes between 100 and 500 years for a plastic bag to fully decompose, depending on the plastic. As a result, a new EU directive has been introduced to lower the annual consumption to 40 bags per EU citizen by 2025.

Germany wants to avoid going down the legislative route and is therefore looking for other alternatives. One of these is an agreement between the Federal Ministry of the Environment and the German Retail Association whereby 80 percent of all plastic bags, which are currently free of charge, will be subject to a charge within the next two years. A start has already been made:

Since 1 July 2016, plastic bags are no longer given out for free in supermarkets or in many other stores. It is up to each retailer to decide how much they cost.

The bag problem is being tackled by legislative means in many other countries. The latest example is in England where a law on the matter was introduced only last October. Since then, every plastic bag costs at least 5 pence (6 to 7 cent) at retailers with more than 250 employees, which are mainly retail chains. The initial result is positive. In 2014, the seven largest retail chains were still handing out 7.6 billion bags to customers –six months after the legislation was introduced, this figure dropped to 640 million bags. It remains to be seen whether this will stay this way in the long run.

The effect on the environment. The vast majority of commercially available single-use plastic bags are made from plastic polyethylene. The raw material used is generally virgin material from fossil crude oil. In a life cycle assessment carried out in 2014, the Swiss Federal Laboratories for Materials Science and Technology (EMPA) found that single-use plastic bags made from polyethylene with a recycling rate of at least 80 percent are ecologically more advantageous - even compared to other single-use and multiple-use bags such as regular plastic bags made from virgin material, paper bags, compostable bags and cotton bags.

For this reason alone it is questionable whether the EU is on the right track with its plan to abolish plastic bags - or whether it would not be better to switch to recycled plastic bags.

From a technical point of view, all these varieties are reusable bags and how often they are used depends more on consumer behaviour than the material. In fact, according to an Emnid survey carried out in 2012, 72 percent of German consumers indeed frequently reuse their shopping bags.

For a better life cycle assessment eco-balance, the frequency of use is definitely the most important factor: In order to have a lower environmental impact than a recycled bag, a cotton bag must be used at least 83 times.

Compostable bags are already better than recycled plastic bags after the twelfth use and paper bags after the eight use. However, either way, the question arises as to whether the material can last long enough to minimise the environmental impact through frequent use.

Even plastic bags from renewable raw materials would have to be used at least four times in order to beat recycling bags. The reason for this is that bio-based plastics create new problems because the cultivation of the necessary raw materials such as maize, potatoes or sugar cane has a negative effect on the environment, among other things, due to the over-fertilisation of soils.

Environmentally friendly disposal. The high level of attention that the European Union is devoting to plastic bags is due to the pressure resulting from the pollution of the world’s seas with plastic waste. At the moment, plastic waste accounts for three quarters of all marine litter waste at sea.

The main reasons for this are consumer behaviour and inadequate waste management structures - or in other words, the environmentally harmful disposal of plastic bags.

In Germany, this sort of thing really should not happen because unlike many other countries, it has the “yellow bag” and the “yellow bin”, which are both part of the so-called Dual System (box).

However, even this does not make any difference if plastic bags are carelessly thrown away or used as bin bags, thus ending up in the household waste.