In the developed world today, the most common end-destinations for our clothes, accessories and shoes are either landfills or incineration. In fact, in the United Kingdom alone, about 900 000 tons of clothing, footwear and household linen are put into the household waste and sent to landfill or incinerated every year (source). Similarly, in Sweden, an estimated 75 000 tons of textiles are incinerated together with the household waste annually (source).
Yet, the majority of our products contain a mixture of materials, some of which can naturally biodegrade and others which are very persistent to degradation. For example, plastics, polyester, nylon and acrylic have very low biodegradability rates. In fact, it may take up to 500 years for a polyester top to degrade in the landfill.
As for those wasted clothes etc that we instead send to incineration (often at the municipal power plant), various harmful gases and particles may be produced during combustion and hence released into the air. Some gases may be cancerogenic, allergenic and/or hormone disruptive and thus harmful to human health or ecosystem functioning.
In order to minimize the risk for any harmful compounds to be released into our environment, it is crucial that we design and produce products that are 100 percent safe and effective to both biodegrade or incinerate. (This, as we rarely know at the design stage if the product will be sent to landfill or burnt in its end of life.)
Thus, for safe and effective biodegradation, all components of a product must be non-toxic and effective to biodegrade. This means that:
- Only natural fibers, such as cotton, flax (linnen), wool, silk, bamboo, viscose (tencel), and wood can be used.
- The thread, buttons and laces must also be made out of natural materials, such as cotton or silk and wood, respectively.
- If some parts are made out of non-biodegradable materials, for example the zipper, this must be easily separated from the other components before biodegradation.
For safe and effective incineration, all components must be combustible and free from non-toxic substances or compounds. Also the products must be produced with rigorous consideration to all relevant chemical regulations and legislations worldwide (such as REACH).
In principle, biodegradation should always be preferred before incineration, because biodegradation creates nutrients that will be reused in new value-creating processes in the ecosystem while incineration will mainly create energy. An exception would be a situation where there is an acute energy deficit or need, which would require all possible sources of energy to be used.