Working Report No. 24 2007 – EDIPTEX - Environmental assessment of textiles

EDIPTEX - Environmental assessment of textiles

6 The EDIPTEX case stories

6.1 The T-shirt, the jogging suit and the work jacket - case group I
6.2 The blouse, the tablecloth and the floor covering - case group II

The six case stories (environmental assessments - lifecycle assessments) vary a lot in scope. They can be divided into two main groups - with variations within these two main groups. The two main groups are:

Group I: Products 1, 2 and 3 in table 2.1, i.e. the T-shirt, the jogging suit and the work jacket.
Group II: Products 4, 5 and 6 in table 2.1, i.e. the blouse, the tablecloth and the floor covering.

The division into groups I and II relates to the scope of the collection of data as well as the quality of data.

As previously mentioned, the case stories are placed separately in annexes 1-6 and structured so that they can be read individually.

6.1 The T-shirt, the jogging suit and the work jacket - case group I

For group I, it was possible to collect (and process) data for all significant processes. The data are of such quality that these three products have been selected to illustrate how far it is possible to take lifecycle assessment for textiles and to illustrate all relevant aspects of the EDIP method.

6.1.1 Case for T-shirt

Within group I, the case for the T-shirt is special as regards the relevant aspects of the EDIP method. It was possible to make assessments of human toxicity and ecotoxicity for all types of chemicals used and to calculate the equivalency factors that are central to the EDIP method (please refer to annex 7: "Management of chemicals in EDIPTEX" for a more detailed description of this very complicated subject).

Moreover, this case applied an almost complete set of data for the unit process "cotton cultivation and harvest". Annex 8 describes in detail the extensive work on this central process. The project group does not know of more thorough and comprehensive work in this area.

For the T-shirt, a lot of work was put into describing what is called "source identification" in EDIP jargon. It is often necessary to study the large information volumes included in the results of a lifecycle assessment in order to achieve the best possible benefit of the assessment. A process is composed of a number of factors that all contribute to the environmental impact categories. By carrying out source identification, the reasons for the individual contributions can be found.

This knowledge makes the assessment more useful for the producer, as the producer can change factors with undesired environmental impacts already in the development phase.

The case story presents an overview of the most important contributions to the following categories:

Primary energy
Resource consumption
Toxicological environmental impacts
Environmental impacts related to energy
Environmental impacts related to waste

A number of what-if simulations or scenarios were prepared for the T-shirt.

The environmental profile for a given product can be affected by the choices made by the producer and by the consumer. In order to elucidate the consequences of possible changes in the product's lifecycle, a number of scenarios have been prepared that focus on the producer and consumer respectively.

By changing one or more of the reference conditions, it is possible to form a picture of the scope of the consequences based on the choices made by the producer and the consumer, and subsequently assess the results of the choices.

9 and 10 different producer and consumer scenarios respectively were prepared for the T-shirt. An example of a producer scenario is "Choice of raw materials - organic cotton", and a consumer scenario could be "Reduced washing temperature from 60 °C to 40 °C".

6.1.2 Case for jogging suit

The jogging suit case is very similar in scope to the T-shirt case, and "source identification" was also carried out here. However, there are "only” seven and four different producer and consumer scenarios respectively.

By contrast, the jogging suit is much more complicated than a T-shirt, which is a simple single-layer product.

The jogging suit consists of top and trousers - outer fabric (nylon) and a lining (cotton) - and the top includes a polyester zipper (both tape and chain). This case illustrates that with the EDIPTEX database and the EDIP PC tool it is possible to work with very complex products.

The quality of data for production of nylon fibres is not as good as that of the data for cotton in the T-shirt case. Data for nylon originates from the series of lifecycle assessment cases (v. Boustead) the fibre industry conducted and published in the 1990s. These lifecycle assessments contain a lot of quality data on energy consumption and emissions into air and water. However, it is not always possible to check/calculate how emissions data have been obtained. Moreover, industry states many emissions in groups like "aldehydes", and it is not possible to calculate the essential equivalency factors for such groups. However, there is currently no better data than those of the industry, so the unit process for nylon in the EDIPTEX database represents the knowledge currently available. Therefore, in terms of lifecycle assessment quality, cases that include nylon, like the jogging suit (and the blouse), are not fully comparable with cases where only cotton is included.

6.1.3 Case for work jacket

The work jacket consists of 65 per cent polyester and 35 per cent cotton, including zipper and brass buttons. The same applies to data for polyester fibres as to nylon (see the jogging suit case). Source identification has not been prepared for the work jacket. The project group considered that this aspect of lifecycle assessment and EDIP is sufficiently covered for the T-shirt and the jogging suit. Five and three producer and consumer scenarios respectively were prepared - including the scenarios "Household wash vs. industrial wash" and "Dry cleaning vs. industrial wash".

6.2 The blouse, the tablecloth and the floor covering - case group II

For group II, it was not possible to complete all sub-processes. Although only 1-2 sub-processes for each product have considerable lack of data, these processes are deemed potentially significant for the overall lifecycle assessment. The group II case stories are therefore of an entirely different character than those of group I. The group II cases illustrate that it is possible to tell an interesting and exciting "environment story" based on lifecycle assessment (and EDIP) even though it has not been possible to analyse all aspects of lifecycle assessment data. This situation will arise very often in lifecycle assessment work. However, there is a significant difference in this EDIPTEX connection; it is possible to draw on results from the three lifecycle assessments from case group I (and this has been done), which improves the quality of the case stories.

6.2.1 Case for blouse

The blouse is composed of 70 per cent viscose, 25 per cent nylon and 5 per cent elastane.

The same applies to viscose fibres as for nylon (see the jogging suit case). Data for elastane were not available, but a process has been established for elastane where data for polyurethane flexible foam are used (elastane consists of 85 per cent polyurethane). It is uncertain how "correct" this assumption is.

These aspects of data quality mean that the primary focus for this case is on primary energy and environmental impacts. However, a statement of toxicological environmental impacts has also been made (there is quite a lot of data on impacts of other chemicals used) - and the significance of the lack of data for the statement is discussed.

6.2.2 Case for tablecloth

The tablecloth is made of 100 per cent cotton. The tablecloth is printed with pigments and has been finished to make it easier to maintain.

Chemical emissions to the air while drying after pigment printing have been difficult to manage. Furthermore, it has not been possible to obtain data to enable calculation of equivalency factors for an important finishing chemical.

As for the blouse, this case primarily focused on primary energy and environmental impacts. The same applies for toxicological environmental impacts - including discussion of the importance of lack of data.

6.2.3 Case for floor covering

The floor covering consists of pile (the surface) of 100 per cent nylon, a primary backing material of 100 per cent polypropylene (to which the pile is stitched), and the actual backside of latex foam.

The same applies for data for polypropylene as for nylon (see jogging suit case).

It has not been possible to collect data for the production of the primary backing material of polypropylene fibres. At an overall level, this process corresponds to the process "weaving" for the jogging suit and work jacket cases. Therefore, the floor covering model is based of data for weaving, which seems to be a reasonable assumption.

Emissions of chemicals into the air during production of the floor covering have turned out to be difficult to handle, and have thus not been included in the model. However, energy consumption during the processes has been included.

As for the blouse and the tablecloth, this case primarily focused on primary energy and environmental impacts. The same applies for toxicological environmental impacts - including discussion of the importance of lack of data.