In the Cradle to Cradle model, all materials used in industrial or commercial processes–such as metals, fibers, dyes–are seen to fall into one of two categories: “technical” or “biological” nutrients. Technical nutrients are strictly limited to non-toxic, non-harmful synthetic materials that have no negative effects on the natural environment; they can be used in continuous cycles as the same product without losing their integrity or quality. In this manner these materials can be used over and over again instead of being “down cycled” into lesser products, ultimately becoming waste. Biological Nutrients are organic materials that, once used, can be disposed of in any natural environment and decompose into the soil, providing food for small life forms without affecting the natural environment. This is dependent on the ecology of the region; for example, organic material from one country or landmass may be harmful to the ecology of another country or landmass.
Biological and technical cycle
The two types of materials each follow their own cycle in the regenerative economy, envisioned by McDonough and Braungart.
The certification criteria in MBDC C2C certification process are: ‘Material Health’, which involves identifying the chemical composition of the materials that make up the product. Particularly hazardous materials (e.g. heavy metals, pigments, halogen compounds etc.) have to be reported whatever the concentration, and other materials reported where they exceed 100 ppm. For wood, the forest source is required. The risk for each material is assessed against criteria and eventually ranked on a scale with green being materials of low risk, yellow being those with moderate risk but are acceptable to continue to use, and red for materials that have high risk and need to be phased out. Grey for materials with incomplete data. The method uses the term risk’ in the sense of hazard (as opposed to consequence and likelihood).
The next assessment is of ‘Material Reutilization’ which is about recovery and recycling at the end of product life. The third assessment is of energy required for production, which for the highest level of certification needs to be based at least 50% on solar for all parts and subassemblies. Fourth is water, particularly usage and discharge quality. The fifth area is ‘social responsibility’ which refers to fair labor practices. The certification is available at several levels: basic, silver, gold, and platinum, with more stringent requirements at each.