by Peter Malaise”

This article is a personal opinion based on 40+ years of practice and might differ in some points from general ideas on the matter.

Historical background

Both Cradle-to-Grave and Cradle-to-Cradle concepts have been practised by mankind for thousands of years, but mostly in an unconscious way and surely without using those terms. In old times there were no fossil derivatives and no synthetic¹ substances: all raw materials were taken from mineral/metal, plant and animal sources.

• Mineral/metal substances return to nature in an almost identical form: minerals/metals are mostly stable chemical elements (cfr. the Mendeliev table) which can not be destroyed.
• Plant substance is relatively unstable, it easily and rapidly biodegrades, with only water, CO2 and a tiny amount of minerals left.
• Animal substance is relatively unstable as well, except for part of the bone structures of mammals; after biodegradation only water, CO2 and a small amount of minerals are left.

The advantage of plant and animal sources is, that they are renewable and rapidly and completely biodegradable, without stable leftovers.
Mineral sources are not renewable, but many of them – i.e. silicates – are so abundant that there is no risk that they will be depleted one day. They are not biodegradable either.
Metals are not renewable, they are only present in small quantities on this planet; they are not biodegradable. Because of the huge actual demand, their scarcity is growing.

In all former human cultures worldwide, plants and animals were the main sources for everything, food and non-food, and only small amounts of minerals and metals were used complementary.

Since the first industrial revolution largely 200 years ago mankind turned increasingly towards fossil raw materials: peat, brown coal, coal and crude oil. After World War I synthetic materials made from fossil sources started to flood the market. Already in the 1960’s – roughly 40 years later – the negative effects on human health and the environment started to become visible. However, profit-driven economies continued to disregard their responsibility on the matter.

The actual situation is such that most of the fossil sources are already depleted (peat, brown coal), will be depleted on the short term (crude oil) or on the somewhat longer term (coal). Rises the question what future generations will do to have raw materials at all?

Cradle-to-Grave

The primarily use of fossil sourced components generated a problematic situation from the 1960’s onwards. Where formerly – with a smaller world population and a different consumption pattern – the available amount of such raw materials was sufficiently large, the new situation rapidly exceeded the capacities of the planet. A large part of those components show a bad behaviour as to aquatic toxicity and biodegradation, leading to accumulation in living nature – in plant, animal and human organisms. Part of them show even an outspoken animal and/or human toxicity, when not acutely, then chronically. The negative outcomes of the choice for fossil ingredients are manyfold: source depletion, pollution, environmental pollution, negative health impacts and accumulation of stable leftovers in the global environment.

In the wake of these issues rose the idea of making producers responsible for the life cycle of their products: the Sourcing phase, the Use phase, the Assimilation phase. It’s going no further than turning an old, subconscious ethical behaviour in a conscient one. A patchwork of loose-end regulations and laws came to life, often very different from one continent to another, or from one country to another, the idea however was – and still is – fought by conventional industry because, so they say, it kills profit.

Originally the main stress of this responsibility made conscious was on the responsible use of raw materials, later on it grew into what some call now Cradle-to-Grave (C2G), where Cradle refers to the sourcing and transformation phase, and Grave to the absorption phase in which raw materials should disappear again in global nature. C2G is putting the stress on the complete route of a substance or a product rather than on different phases. It is also called Full Life Cycle Assessment (Full LCA) to distinguish it from the ‘average’ LCA, which responds to ISO 14040 and 14044. This latter LCA knows a lot of parent forms invented by industry, with the main purpose of window-dressing: when the numbers don’t come out too well in one form, they might do in another. With C2G however all parameters should be taken in account, nothing left out.

Michael Braungart, a German chemist and Bill McDonough, an American architect, published in 2002 a book titled ‘Cradle to Cradle: Remaking the Way We Make Things’². They criticised the reduce-reuse-recycle pattern as perpetuating a C2G strategy, whereas more changes are needed. In their point of view, downcycling (turning things into some form of waste) should be left in favour of upcycling, a life cycle development strategy which allows products to become biological or technical nutrients after a first use.

Cradle-to-Cradle

The C2C principle goes a step further than C2G. After a product has been used, it should become a biological or technical nutrient. Obviously this principle is of great value for durable consumer goods, such as furniture, tools, equipment, cars, engines etc. Whatever object it is, it should have been designed to be fit for dismantling and the separate parts or components should be upcyclable by further processing.

C2G however is still of high interest for such consumer goods that are destroyed at use: food, medicine, cosmetics, cleaners and some more categories. All of them are shortlived, non-durable goods. With those products recycling is either impossible, or not at all effective. It will be obvious that the recuperation and upcycling of food, medicine, cosmetics and similar is inherently impossible. For certain other applications there might be solutions in the future, but even then the smart disposal of such goods will most probably outperform the physical, logistical and financial effort for their upcycling.

An absolute requirement in case of a C2G approach is that the goods have to be designed for safe disposal and will in no way put an unacceptable stress to living nature or human health, and that there will be no stable leftovers. Almost all of the actual consumer goods would not respond to such requirements.

Often, C2C is presented as the better solution, a higher level than C2G, not to say the ultimate solution. This is the case in the vision of Braungart and McDonough.
Personally, I disagree with that point of view. There are many, many issues that can be effectively solved through smart C2G approaches, without any negative outcome for human health or environment, and where going for a C2C solution would be a blatant waste of time and effort.

Some product categories, such as cosmetics or cleaners, are presumed to be C2C because their metabolites – mostly water, CO2 and traces of minerals – are automatically returning into living nature as biological nutrients. In my perspective, that is not really what should be the purpose of the C2C classification. To be classified as such, there must be an inherent possibility to upcycle the core of the product, which is not the case with commodities that are destroyed at use. Biological nutrients and technical nutrients belong to different cycles and should preferably be evaluated against their own ways.

That being said, there is formally little against a C2C classification for goods destroyed at use, as far as they respond to the lifecycle design criteria.

Conclusion

C2G and C2C are both valuable methodologies in the quest for sustainable solutions. Either one has strengths and weaknesses; and both together bear also a certain risk. A product can be top-of-the-bill C2C – but not really fit for use. The C2G/C2C classification is saying nothing about the performance of a given product, only something about its sustainability level and its evaluation should therefore be completed with a performance assessment. A product that is not fit for use can’t be considered to be a sustainable solution.