The PET bottle - nerd or bogeyman?

Plastic, including PET bottles, is repeatedly the subject of criticism. But how do independent experts actually view this discussion? Benedikt Kauertz, head of the Industry and Products department at the independent ifeu Institute in Heidelberg, explains in an interview why arguments for the seemingly poor life cycle assessment do not hold up from a scientific perspective.

Plastic is under public pressure. In some cases, it is identified as the cause of numerous environmental problems. How do you experience the discussion?

In public, we sometimes perceive an enormous simplification of the facts. Admittedly, life cycle assessments for the neutral evaluation of packaging types are very complex. Material requirements, energy input in production and recycling, the proportion of recycled PET material in new bottles and much more all play a role. Which type of packaging is suitable for a particular product depends on several factors. Therefore, one should not demonize a certain type of packaging across the board.

How does PET beverage packaging currently perform from an environmental perspective?

PET bottles have a comparatively good life cycle assessment. This is due in particular to their light weight and the associated CO₂-savings in transport compared with heavier glass, for example. A great deal has happened in this area. These positive properties of PET bottles apply to lemonade as well as still and carbonated water. These are, of course, the most relevant types of beverage on the German market for which plastic plays a role as a packaging material. In addition, the one-way deposit has a positive effect here. The recycling cycles are virtually closed. This in turn favors a positive eco-balance. Contrary to popular belief, PET bottles do not contain any plasticizers.

You speak positively about PET. From your point of view, where does the negative basic public attitude come from?

Although the introduction of the single-use deposit in 2003 had a positive effect on public opinion, the criticism of PET bottles that persists to this day has its origins in this period. The first life cycle assessments by the Federal Environment Agency in 2000 and 2004 were actually already comparatively good. In 2008, the next life cycle assessment came to the conclusion that disposable PET bottles in particular were disadvantageous.

What was the reason for that?

Following the introduction of the one-way deposit in 2003, many discounters initially removed beverages made from non-refillable PET bottles from their product ranges. As a result, the market consolidated. The filling of PET bottles was concentrated among just a few manufacturers. When the discounters gradually reintroduced non-refillable PET bottles into their product range, the remaining mineral springs had to deliver over long distances. This negative factor was compounded at the time by comparatively heavy bottles and the use of recycled PET material, which was virtually nil. There was also hardly any recycling capacity in Germany. All this was included in the 2008 life cycle assessment. Since then, the public has been told: Right of way for reusable containers - until today. However, this generalized statement no longer stands up to today's findings.

What was the next step in terms of ecobalance?

When the life cycle assessment was published in 2008, it was already clear that life cycle assessments for PET packaging would improve. In 2010, we prepared the last ISO-compliant life cycle assessment to date with regard to beverage packaging on behalf of the IK Industrievereinigung Kunststoffverpackungen. In it, we came to the following conclusions: PET returnable bottles are more advantageous than glass returnable bottles. And in certain segments, non-refillable PET bottles are even equivalent to refillable glass bottles in terms of life cycle assessment. The fact that four 0.75-liter returnable glass bottles and only two 1.5-liter PET bottles are required for three liters of mineral water certainly plays a role here. The LCA takes this effect into account by scaling all results to a comparable level, namely 1,000 liters of beverage. This alone, of course, had a positive impact on non-refillable PET bottles. Added to this were weight savings and better recycling capacities.

Accordingly, PET should be perceived much more positively as a packaging material.

To date, critics of plastics have actually tended to propagate the arguments from the 2008 life cycle assessment. This stands in the way of new findings.

...and this despite the fact that the bottles have been further optimized in the current decade.

That is correct. Non-refillable PET packaging in particular has been optimized more and more. In the past, 40 grams was considered the standard weight for a 1.5-liter non-refillable PET bottle. Today, there are 1.5-liter bottles for still water that weigh only a little more than 20 grams - an enormous advance.

Against this background, isn't it time again for a new life cycle assessment?

It would certainly make sense to take another look. However, this fails due to the lack of comparative figures from the glass bottlers. And after the experiences in 2010, the PET industry is also likely to have little interest in this for the time being due to the partly biased public discussion - as good as the new figures would be.

So you assume that the life cycle assessment would be even more favorable for PET packaging today?

Yes, a great deal has simply happened here. While PET reusable packaging was actually considered the most advantageous beverage packaging in the past, highly optimized PET disposable packaging has already caught up with it today. These bottles are very light and have a recycled PET material content of more than 50 percent. And there is a second circumstance on the other side.

Namely which one?

The glass reusable system is coming under more and more pressure. Branded beverages are increasingly coming onto the market in individually designed returnable bottles. These, in turn, cannot be used by other beverage bottlers, as the returnable system actually envisages. A Deloitte study attests that the actual uniform refillable bottles have a higher number of refills than the individual glass refillable bottles. Their increase may have a negative impact on the reusable eco-balance.

Higher reusable quotas are being demanded. Against the background just described, is this reusable/disposable discussion still up to date?

From our point of view, it's a clear no. We don't think that a fixed reusable quota would achieve the environmental goals. The Packaging Act currently prescribes such a quota of 70 percent. However, there is no differentiation whatsoever. This quota is based on blanket assessments, which in some cases contradict the results of life cycle assessments carried out in recent years or present partial results as generally valid. Instead of a blanket reusable quota, we therefore propose fixed target values for both reusables and disposables.

What could these look like?

In the case of refillable bottles, for example, a long-term commitment should be made to standardized refillable bottles as opposed to individual ones. A minimum number of bottles in circulation should be anchored. For non-refillable PET bottles, a certain proportion of recycled PET material or a certain ratio between filling volumes and packaging weight could be stipulated. A 50 percent share of recycled PET material in new PET bottles should not remain an exception, but should become standard. The increased use of bio-based plastics could also further improve the eco-balance of disposable bottles. However, these must then in any case be recyclable within the framework of the current closed-loop system.

Beverage producers regularly come to you for advice on the choice of packaging type. What advice do you give them?

This much is certain: there is no universal packaging solution. If, for example, a juice producer delivers regionally to the retail trade, returnable glass is a good choice from an ecological point of view. Plastic packaging for juices is partly made of polyamide in addition to PET because of the necessary barrier properties. As a result, they cannot simply be included in the PET material cycle, which in turn has a negative impact on the life cycle assessment. PET disposables, on the other hand, certainly offer advantages for delivery to the discount store over long transport distances and for large filling volumes. In addition to these life cycle assessment issues, however, many other parameters play a role in the choice of packaging material - for example, the level of investment in new machine technology or the properties of the packaging material, which are very important for manufacturers and retailers. Here, PET disposable packaging has advantages due to its unbreakability, ease for the end consumer, and individual design options.

Where do you see the beverage market heading?

As long as the legal framework does not change drastically, there will certainly not be the big upheavals. We expect a further increase in PET packaging for milk and milk-mix beverages. Non-refillable PET bottles will certainly also be further optimized in the process. Thanks to special inner glass coatings already available today, PET bottles for juice are an alternative that can also be used for juice bottles and recycled with single-variety PET material. Currently, a lot of attention is focused on further material savings. The fact that retailers have discovered this topic for themselves is certainly positive for the overall improvement of PET eco-balances. If larger players in the market lead the way - including beverage producers - others will follow suit.

(Source: Forum PET)

Benedikt Kauertz

Benedikt Kauertz is an expert in the field of life cycle assessment of packaging. Since joining the ifeu Institute in Heidelberg, he has been studying their environmental impact from various angles. Today, he is head of the Industry and Products department. The focus is on all types of packaging, from films and paper to glass. The ifeu Institute researches and advises on all major environmental and sustainability issues worldwide. With almost 40 years of experience, it is one of the most important ecologically oriented research institutes in Germany. Among other things, it has often cooperated with the Federal Environment Agency in the field of packaging balancing.

www.ifeu.de