Is Unbleached Cotton Better Than Bleached? Exploring the Limits of Life-Cycle Assessment in the Textile Sector

Abstract

The applicability of life-cycle assessment (LCA) for the textile industry is discussed with a special focus on environmental impact from chemicals. Together with issues of water depletion and energy use, the use of chemicals and their emissions are important environmental considerations for textile products. However, accounting for chemicals is a weak point in LCA methodology and practice. Two research questions were investigated in a case study of hospital garments: 1) whether LCA adds value to assessments of the chemical performance of textile products, and 2) whether inclusion of toxicity issues in LCA affects environmental performance rankings for textile products. It is concluded that the quantitative and holistic tool LCA is useful for environmental decision makers in the textile industry, and becomes more effective when chemical impacts are included. A flexible way forward is demonstrated to meet the challenge of accounting for chemicals in LCAs of textile products.

Keywords

design process environment green products product development sustainable design decision making

The environmental issues associated with textile products that have commanded the most attention by analysts are energy use, water depletion, and chemicals (Allwood, Laursen, Rodriguez, & Bocken, 2006), while land use is increasingly attracting attention (Sandin, Peters, & Svanström, 2013). The chemicals of concern for textiles are located along the whole supply chain, from pesticide and fertilizer use in cotton cultivation to toxic emissions from wet treatment and toxic chemicals in the after-treatment (European Commission, 2003). The choice among dyestuffs for textiles is crucial for the local environment at wet treatment sites in the exporting countries, as dyestuffs can be carcinogenic, toxic, and/or persistent (Shams-Nateri, Hajipour, Dehnavi, & Ekrami, 2014). The choice of dyestuff is also relevant for the environment in the importing countries as well as for consumer health with regard to avoiding potential carcinogenic and allergenic properties (Malinauskiene, 2012; Sasaki, Sarai, Matusita, Masuda, & Sato, 2008). Textile consumer products and wastewater from washing have been found to contain undesirable degradation products such as arylamines from azo dyes, as well as residues of process chemicals such as alkylphenol ethoxylates.

In this article, life-cycle assessment (LCA) as defined by the ISO 14040 standard (International Organization for Standardization [ISO], 2006a) is the method with which the environmental performance of garments is analyzed. LCA differs from other environmental assessment methods in that it quantitatively evaluates the environmental pressures and benefits associated with the full life cycle of products or services, comprising the production of raw materials, manufacturing, use and waste management, and/or recycling. The broad scope of LCA reduces the risk that a decision aimed at reducing pollution simply shifts the environmental problem from one phase to another or one environmental issue to another. The environmental scope of LCA is versatile and is determined by the selection of impact categories. Common impact categories are global warming potential (GWP), acidification, eutrophication, and photochemical smog formation, which are further explained by Beton et al. (2014). Which impact categories are the most important depends on the product category (European Commission, 2010). For example, products that use energy, such as radiators and tumble dryers, generally make relatively large contributions to GWP, whereas toxicity is more important for chemical products such as insecticides, due to emissions of ecotoxic substances. LCA results are increasingly used in environmental declarations, procurement guidelines, product design, and regulatory work, all of which potentially impact the entire life cycle of a textile product (Curwen, Park, & Sarkar, 2013). However, textile chemicals are not always fully covered in LCA (Beton et al., 2014), as will be discussed in more detail subsequently.

LCA is one of several available complementary tools for managing sustainability in the textile industry. Cradle to Cradle^® (C2C^®) is another commonly applied framework for the sustainable design of textile products (McDonough & Braungart, 2002). In a comparison made by Bor et al. (2011), LCA differs from C2C in that it is a quantitative and holistic method and is independent of commercial interests. Other textile companies choose to follow schemes such as Bluesign^® (BLUESIGN®, 2013) to manage environmental impacts in the supply chain, the Business Social Compliance Initiative (2013) for social sustainability, or OEKO-TEX^® (OEKO-TEX® Association, 2013) to ascertain the absence of hazardous chemicals in the textile chain. The Higg Index from the Sustainable Apparel Coalition (SAC 2012) and the Chemicals Management Framework from the Chemicals Management Working Group (Outdoor Industry Association, 2014) are based on the evaluation of management procedures. LCA stands out as a tool that can give quantitative answers considering multiple environmental issues along the whole life cycle of alternative products, technologies, and management procedures to designers, purchasers, and consumers. In our experience, LCAs typically cost between USD 10,000 and 250,000—the price depends on the complexity but for routine work is usually toward the lower end of this scale. The main value of a quantitative environmental evaluation is that the cost of different management measures can be related quantitatively to the environmental improvement potential they are expected to lead to, and thus guide product procurers, designers, and other environmental decision makers to make eco-efficient decisions. The quantitative evaluation can also relate the monetary price of a product to the environmental cost and guide consumers as well as professional buyers. As the use of LCA for policy making in both industry and the public sector is continuously increasing (European Commission, 2014; Peters, 2009), it is important that LCA is developed further to enhance its relevance and reliability as a methodology for the textile industry.

Background

Coverage of Chemicals in Inventory Analysis and Impact Assessment

According to the ISO 14040 and 14044 standards (ISO, 2006a, 2006b), an LCA is carried out in the following four distinct phases: (a) goal and scope definition, (b) life-cycle inventory analysis (LCI), (c) life-cycle impact assessment (LCIA), and (d) interpretation of results. The LCI is a comprehensive list of relevant inflows and outflows of energy and materials for each process included in the product’s life cycle. The LCIA method used in the impact assessment contains characterization factors (CFs) that relate the inflows and outflows from the inventory to potential environmental impacts (Pennington et al., 2004). ISO 14044 states that the CF “is applied to convert the assigned LCI results to the common unit of the category indicator” (p. 2). It is a linear factor, which for chemicals is typically calculated using a steady-state, multimedia, and multicompartment model of the environment. For more information on the USEtox LCIA method, the reader may consult Rosenbaum et al. (2008). To be included in the LCA, an emission of chemicals must thus be both listed in the LCI and have a CF. For more description of LCA methodology in general, the reader is referred to ISO 14040, ISO 14044, and the handbook produced by the European Commission (2010).

Treatment of chemicals in textile LCI

How chemicals have hitherto been taken into consideration during LCI of textiles is described in Table 1 and categorized by relevant life-cycle stage (raw material extraction, manufacture, use and end of life). The raw material extraction phase includes agriculture for natural fibers, forestry for regenerated fibers, oil extraction for synthetic fibers, and fiber refining for all types of fibers. The manufacturing phase includes yarn spinning, fabric construction, wet treatment, and confectioning. The use phase includes use of the garment, washing, and drying. The end of life phase includes disposal of the garments, generally combustion or landfill. Although approximately 75% of preconsumer textile waste is recycled, postconsumer textile waste is rarely recycled (Chen & Burns, 2006). Transport is included in all the phases. Emissions of chemicals from energy production and fuel use, such as carbon dioxide and particulates, are, for the purpose of this article, not considered to be textile chemicals. In Table 1, the sources for which toxic emissions from background processes, such as electricity production, are aggregated with foreground processes, such as cotton cultivation, and cannot be distinguished in the inventory are marked as aggregated (A). The other sources are marked as either quantitative (Q) or qualitative (q). Table 1 reveals significant gaps, since quantitative inventories exist only for a few materials and life-cycle phases.

Table 1.

Public LCA Studies of Textiles in the Scientific Literature and Quantitative or Qualitative Inclusion of Textile Chemicals in the LCI.

Life Cycle Phase With Exposure to Textile Relevant Chemicals	Cotton	Polyester	Polyamide	Elastane	Viscose/Modal	Lyocell	Wool
Raw material extraction
Pesticides/fertilizers	Q1, q2	N/A	N/A	N/A	—	A3	A4
Monomers and additives	N/A	q5, A6	q5, A6	—	N/A	N/A	N/A
Fiber spinning additives	N/A	q5, A6	q5, A6	q7	q5	A3, q5	N/A
Manufacture
Yarn spinning lubricants	q7	q7	q7	q7	q7	q7	q7
Sizing agents	q7	q7	q7	q7	q7	q7	q7
Knitting lubricants	q7	q7	q7	q7	q7	q7	q7
Scouring, desizing, etc.	q7	q7	q7	q7	q7	q7	q7
Reactive continuous dyeing	Q8, Q9	N/A	N/A	N/A	q7	q7	q7
Reactive exhaust dyeing	Q10	N/A	N/A	N/A	q7	q7	q7
Disperse, direct, etc., dyeing	q7	q7	q7	q7	q7	q7	q7
Spin dyeing	N/A	q7	q7	q7	q7	q7	N/A
Wet finishing	q7	q7	q7	q7	q7	q7	q7
Dry coating	q7	q7	q7	q7	q7	q7	q7
Waste water treatment	q7	q7	q7	q7	q7	q7	q7
Transfer, roller, etc., printing	q7	q7	q7	q7	q7	q7	q7
Transport biocides	—	—	—	—	—	—	—
Use
Exposure to skin from wearing	—	—	—	—	—	—	—
Leakage during washing	—	—	—	—	—	—	—
Wet cleaning agents	A11, Q12, Q13, A14
Dry cleaning agents	A14, Q15
End of life
Emissions from incineration, landfill leakage, or recycling processes	q16	q16	—	—	—	—	—

Note. Q = quantitative LCI in the reference; q = qualitative discussion in the reference; A = inventory including chemicals has been made but only shown as aggregated results; Q1 = Cotton Incorporated (2012); q2 = Kalliala and Nousiainen (1999); A3 = Shen, Worrell, and Patel (2010); A4 = Barber and Pellow (2006); q5 = European Commission (2007); A6 = Boustead (2003); q7 = European Commission (2003); Q8 = Beck, Scheringer, and Hungerbühler (2000); Q9 = Yuan, Zhu, Shi, Liu, and Huang (2012); Q10 = Murugesh and Selvadass (2013); A11 = Krozer et al. (2011); Q12 = Saouter, Perazzolo, and Steiner (2011); Q13 = Schulze et al. (2001); A14 = Keoleian, Blackler, Denbow, and Polk (1997); Q15 = Hellweg, Demou, Scheringer, McKone, and Hungerbühler (2005); q16 = Zamani, Svanström, Peters, and Rydberg (2014).

Approaches to incorporating chemicals in LCIA

The recommended LCIA method by the European Commission for toxicity impacts, the USEtox™ method (Rosenbaum et al., 2008), is not complete for textile chemicals (Terinte, Manda, Taylor, Schuster, & Patel, 2014). As the development of CFs is resource-demanding, previous researchers have used a range of methods for simplified incorporation of toxicity in LCIA. A common approach has been to merge the life-cycle perspective with chemical risk information to deal with the problem of missing CF (Askham, 2011; Finnveden et al., 2009; Laurent, Olsen, & Hauschild, 2012; Liu, Ko, Fan, & Chen, 2012; Scheringer, 1999). It has, however, been concluded that the assessment of chemicals is still a weak point in a recent overview of best practices for LCIA in LCA (Sala, Pant, Hauschild, & Pennington, 2012). The SAC (2012) encourages LCA-based environmental product declarations (EPD) of textile products and is in the process of developing guidance material. An interim solution proposed at the SAC Metrics Working Group meeting in January 2013 was to hold all regulated chemicals declarable in the EPD, a nonquantitative solution. The Textile BREF (best reference) document (European Commission, 2003) presents the “Score System,” a semiquantitative tool for assessing the ecotoxicity of textile process emissions, which will be further explored in this article.

Research Questions

The aim of this article is to explore the benefits and challenges of LCA as currently performed in the textile sector. Two research questions are addressed as follows: (a) does LCA add value to assessments of the chemical performance of textile products and (b) does inclusion of toxicity issues in LCA affect environmental performance rankings for textile products. The life-cycle perspective is expected to add value as it avoids improving part of a system (e.g., a process or an environmental aspect) in a manner that negatively affects other parts of the system (“suboptimization”). The current predominantly qualitative assessments of chemicals in the textile product supply chain may prevent the comparative significance of the chemicals from being fully comprehended.

Method

The research questions were examined in a project commissioned by the Stockholm County (SC) where cradle-to-gate (ISO, 2006b) attributional (European Commission, 2010) LCA including chemicals was performed on hospital garments. SC manages several hospitals in the Stockholm region. The goal of the SC project was to investigate whether unbleached garments are more environmentally friendly than bleached garments via a comparison of white hospital nightgowns and to identify the most environmentally benign dyestuff via a comparison of blue cardigans. The following two types of hospital garments were examined: a white, 337 gram nightgown for patients and a blue, 496 gram cardigan for hospital staff. Specific LCI data were collected from the SC suppliers. Generic background data were primarily selected from the ecoinvent database (Swiss Centre for Life Cycle Inventories [ecoinvent Centre], 2010). The schematics of both garments’ life cycles are shown in Figure 1.

Figure 1.

The schematics of the two garment’s life cycles, including system boundaries and data source specification.

The garments were both knitted, cotton/polyester (PES) blends and manufactured in Tirupur, India. In the use phase, the garments were washed in an industrial laundry and used for the whole technical lifespan (i.e., until the fabric or the stitching is worn out). Impacts of use phase processes (washing, drying, and transportation) and disposal were identical for both garment types. In the LCA, environmental performance was expressed as GWP, ecotoxicity, and human toxicity. The GWP was calculated with the LCIA method ReCiPe, Midpoint (H) V1.06/World ReCiPe H (Goedkoop et al., 2013), and the toxicity was calculated with the LCIA method USEtox (Rosenbaum et al., 2008). For further information about the impact categories, readers are referred to the LCIA method publications.

The Score System (European Commission, 2003) was used as a supporting assessment method to calculate the potential ecotoxic impact from textile chemicals. The Score System is a semiquantitative method based on multi-criteria analysis with implicitly equal weighting (Rowley, Peters, Lundie, & Moore, 2012) of four criteria. It does not cover human toxicity. It was developed in the 1990s by the Federation of Danish Textile and Clothing in Denmark (Laursen, Hansen, Andersen, & Knudsen, 2002) and has been integrated into wastewater permit approvals by Ringkøbing County in Denmark. According to the Score System, each substance is given a score from 1 to 4 for each of four criteria (A–D):

A—amount of substance discharged weekly (1 = <1 kg/week) and 4 = >100 kg/week);

B—biodegradability (1 = >60% BOD¹ and 4 = BOD/COD² ratio ≤ 0.5, where BOD = biological oxygen demand and COD = chemical oxygen demand).

C—bioconcentration factor (1 = BCF³ < 100 and 4 = BCF ≥ 100, where BCF is the ratio of a chemical’s concentration in the tissue of an aquatic organism (kg/kg) to the chemical’s concentration in water (kg/L), expressed as L/kg.)

D—toxicity, measured as effect concentration (EC) divided by effluent concentration (1 = >1,000, 4 = <10).

The four scores are then multiplied together so that the lowest possible value is 1 (best environmental performance) and the highest possible value is 256 (worst environmental performance). Missing information invokes the highest score (i.e., in case of data missing for a property, the value of 4 should be given to the substance for that property). For detailed LCA results of the case study, the reader is referred to an earlier publication (Roos & Posner, 2011).

Experimental Design

Comparison of white nightgowns

The SC-commissioned project aimed to quantify the environmental benefits that would follow a decision to purchase only unbleached garments and to create more knowledge of the garments’ life cycle as a whole. Eliminating a process step (bleaching, in this case) seemed intuitively to be environmentally friendly; however, after studying the whole life cycle, another conclusion was reached. Due to the natural impurities such as pectins, hemicellulose, waxes, and debris, unbleached cotton fabric must anyway undergo a scouring step to remove extraneous matter (Carr, 1995). Without this step, the material would be “dusty,” lose the short fibers in the use phase, and be worn out faster. Adding bleach (sodium hypochlorite or hydrogen peroxide [H₂O₂]) during the scouring step aids the process and lengthens the technical lifespan. The scouring and bleaching processes used for the nightgowns were both performed in a jet dyeing machine, which was filled 4 times with a liquor ratio of 1:4. The only difference was that in the bleaching case, 10 g H₂O₂/L was added to the third bath. All other LCI parameters were identical and will not be discussed in this article. H₂O₂ is short-lived and quickly degrades to water in the wastewater. The difference between the two nightgowns was the bleaching process and the longer lifespan of the bleached gown in the use phase. A 5% shorter lifespan is assumed for unbleached gowns due to the loss of short fibers and debris. This is a conservative estimate based on experiences from procurement of unbleached garments in the Norwegian health care sector (T. Pajula, personal communication, March 8, 2011).

Comparison of blue cardigans

SC further commissioned a comparison between two cardigans that were dyed with different dyestuffs in order to quantify the environmental burdens of different dyestuffs and make recommendations for public procurers on what dyestuffs they should require. In a life-cycle perspective, the dyeing question involves issues about the production process, product quality, lifespan, and perceived comfort. Dyeing techniques are highly diverse, both in terms of the chemical choices (vat dyes, direct dyes, and reactive dyes are some possibilities) and the equipment (e.g., pad, jet, and jigger). In this case, only reactive dyeing in a jet machine was considered, as that was the technology offered by SC’s supplier. The only parameter that differed between the two cardigans was the choice of dyestuff; all other LCI parameters (liquor ratio, auxiliary chemicals, and energy sources) were identical and will not be discussed in this article. For further details of the method, the reader is directed to (Roos & Posner, 2011).

Results

Does LCA Add Value to Assessments of the Chemical Performance of Textile Products?

The normalized impact assessment (LCIA) results for the unbleached and the bleached nightgowns expressed as (a) GWP (kg CO₂-eq), (b) ecotoxicity (CTUe [Comparative Toxic Unit ecotoxicity]), and (c) noncarcinogenic human toxicity (Comparative Toxic Unit human toxicity) are shown in Figure 2. The results for carcinogenic human toxicity are not shown as H₂O₂ has no known carcinogenic characteristics (European Chemicals Agency [ECHA], 2013). The results for the H₂O₂ are broken out from the wet treatment.

Figure 2.

Results of the life-cycle impact assessment expressed as (A) global warming potential (kg CO2-equivalents), (B) ecotoxicity (CTUe [Comparative Toxic Unit ecotoxicity]), and (C) human toxicity, noncancer (CTUh [Comparative Toxic Unit human toxicity]). The unbleached and bleached night gowns are to the left of each plot, and the two different cardigans to the right.

The LCIA results for all three impact categories in Figure 2 are dominated by cotton cultivation, yarn spinning, wet treatment, and knitting. This shows clearly that the environmental burden of the addition of the upstream production of the H₂O₂ was insignificant with regard to the whole life cycle. H₂O₂ represents a small part of the wet treatment—whose impact was dominated instead by the energy production for the heating of the water. The background systems for energy production are also the main contributors to the results for the other production steps (PES granulate production, melt spinning, etc.). The total environmental burden was lowest for the bleached nightgown, which was contrary to expectations, and demonstrates the added value of the LCA when assessing chemical performance of textile products. As mentioned earlier, chemical issues are generally assessed on a qualitative basis in the textile production chain, which means that their comparative significance is not always comprehended.

Does Inclusion of Toxicity Issues in LCA Affect Environmental Performance Rankings for Textile Products?

The recipe for the wet treatment of the first blue cardigan mapped to the state-of-the-art LCIA method USEtox CFs (Rosenbaum et al., 2008) is shown in Table 2 as are the hazard phrases for classified substances (i.e., the classification of substances according to the European Regulation [EC] No 1272/2008 on classification, labeling, and packaging [CLP]—CLP-harmonized classification if available, otherwise self-classification). Unclassified substances are not necessarily nonhazardous; this status might simply indicate that they have not been evaluated. A shortcoming identified during the impact assessment step for the blue cardigans was that many textile chemicals lacked CFs and therefore could not be included in LCA calculations. This is of concern since the classification data in Table 2 suggest that several substances currently lacking CFs (such as the softener) should indeed be covered in a toxicity assessment.

Table 2.

The Recipe for Wet Treatment of the Blue Cardigan Mapped to USEtox Characterization Factors^a and CLP Classification.

Process Step	Substance	Use/Application	Dose (g/l)	Classification in CLP^b	Match in USEtox™
Pretreatment	Polyacrylate, anionic	Anti-crease agent	1	H315, H318, H413	No
	Fatty alcohol glycol ether	Antifoaming agent	1	H302, H315, H318, H319, H400	No
	Alkyl phosphonate	Metal complexing agent	1.5	H315, H318, H319, H400, H410	Recommended
	Sodium hydroxide	pH stabilizer	2	H314	No
	Acetic acid^c	Neutralizer	0.5	H226, H314	Interim
Dyeing auxiliaries for PES^d	Polyacrylate, anionic	Anti-crease agent	1	H315, H319, H413	No
	Fatty alcohol ethoxylates	Dispersing agent	2	—	No
	Lignin sulfonate	Dispersing agent	1	—	No
Dyes PES^d	Azo disperse dyestuff preparation a	Disperse dyestuff	Sum^e: 0.25%	H315, H317, H319, H335	No
Dyes PES^d	Azo disperse dyestuff preparation b	Disperse dyestuff	Sum^e: 0.25%	H315, H317, H319, H412, H413	No
Reduction	Thioureadioxide	Reduction agent	3	H251, H302, H315, H319, H330, H335,	No
Reduction	Sodium hydroxide	pH stabilizer	2	H314	No
Dyeing auxiliaries for CO^f	Acrylate, sodium salt	After-treatment agent	1	—	No
	Sodium hydroxide	pH stabilizer	2	H314	No
	Sodium chloride	Electrolyte	100	H315, H318, H319, H335, H373	No
	Acetic acid^c	Neutralizer	0.5	H226, H314	Interim
Dyes CO^f	Azo reactive dyestuff preparation a	Reactive dyestuff	Sum^e: 1%	H412	No
	Azo reactive dyestuff preparation b	Reactive dyestuff	Sum^e: 1%	H317, H318, H320, H334, H335, H412	Recommended
	Azo reactive dyestuff preparation c	Reactive dyestuff	Sum^e: 1%	—	No
After-soaping	Acrylate, sodium salt	After-treatment agent	0.5	—	No
	Acetic acid^c	Neutralizer	0.5	H226, H314	Interim
	Mix fatty amide and fatty alcohol ethoxylates	Softener	3%	H318, H360, H411	No

Note. CLP = classification, labeling, and packaging.

^aUSEtox CFs are divided into recommended and interim CFs, the latter for which uncertainty is high (Rosenbaum et al., 2011). The chemical abstracts service registration number (CAS RN) for each substance is found in the original report. ^bH302: Harmful if swallowed. H314: Causes severe skin burns and eye damage. H315: Causes skin irritation. H317: May cause an allergic skin reaction. H318: Causes serious eye damage. H319: Causes serious eye irritation. H320: Causes eye irritation. H330: Fatal if inhaled. H334: May cause allergy or asthma symptoms or breathing difficulties if inhaled. H335: May cause respiratory irritation. H360: May damage fertility or the unborn child. H373: May cause damage to organs through prolonged or repeated exposure. H400: Very toxic to aquatic life. H410: Very toxic to aquatic life with long lasting effects. H411: Toxic to aquatic life with long lasting effects. H412: Harmful to aquatic life with long lasting effects. H413: May cause long lasting harmful effects to aquatic life. ^cAcetic acid occurs 3 times deliberately to give the possibility to compare the impact of different wet treatment steps. ^dPES is a standardized abbreviation for polyester in the textile industry. ^eThe exact composition of the dyestuffs is not displayed, only the total sum of the dyestuffs. ^fCO is a standardized abbreviation for cotton in the textile industry.

The results of the LCIA calculations for the blue cardigans are shown in Figure 2. As the dyestuffs were omitted from the LCIA due to a lack of published CFs, both versions of the cardigans presented the same result. Therefore, to investigate whether inclusion of toxicity issues in textile LCAs would be expected to affect the result of environmental performance ranking for textile products, a supporting assessment was performed using the Score System (European Commission, 2003) to calculate the potential ecotoxic impact of the textile chemicals. (This was not necessary for the nightgown as the USEtox method covered the chemicals.)

Supporting assessment of cardigans with score system

The ecotoxic impacts of each chemical used in the production of textiles within the SC project, calculated using the Score System are shown in Table 3. To illustrate the application of this method, the evaluation of the first substance in Table 3 is described; for further calculations, the reader is referred to Roos and Posner (2011). The anti-crease agent with chemical abstracts service registration number 25133-97-5 was added at a rate of 1.0 g/L. In the specific case, the water volume was 1 400 L so 1.4 kg was added. Two assumptions were made in order to estimate the weekly discharge as follows: that the process was run 2 times a week and that 50% of the agent was consumed in the process. The discharged amount of 1.4 kg scores 2 in this system (Level 2 means 1–10 kg/week). The biodegradability was “good” according to the safety data sheet (SDS) of the product that was provided by the supplier, warranting a score of 1. The bioconcentration factor, however, was not reported in the SDS and could not be found in other sources (Classification and Labeling Inventory database [ECHA, 2013], SDS, and Google) so the default value of 4 was given. The toxicity criterion was calculated as described earlier, with a value of 1,439, corresponding to Level 1 of the Score System. Multiplying these four figures gives 2 × 1 × 4 × 1 = 8, as can be seen in Table 3. The earlier publication (Roos & Posner, 2011) provides the background data underlying the scores for other substances in this study.

Table 3.

Ecotoxicity Results With the Score System for the Wet Treatment of the Blue Cardigan.

Process Step	Substance	A Discharged Amount of Substance	B Biodegradability	C Bioaccumulation	D Toxic Effect	Score
Pretreatment	Polyacrylate, anionic	2	1	4	1	8
	Fatty alcohol glycol ether	2	1	4	3	24
	Alkyl phosphonate	2	3	4	1	24
	Sodium hydroxide	2	1	1	1	2
	Acetic acid	1	1	1	1	1
Dyeing auxiliaries for PES	Polyacrylate, anionic	2	1	4	1	8
	Fatty alcohol ethoxylates	2	1	4	1	8
	Lignin sulfonate	2	3	4	2	48
Dyes PES	Azo disperse dyestuff preparation a	1	3	4	1	12
Dyes PES	Azo disperse dyestuff preparation b	1	4	4	1	16
Reduction	Thioureadioxide	2	2	4	2	32
Reduction	Sodium hydroxide	2	1	1	1	2
Dyeing auxiliaries for CO	Acrylate, sodium salt	2	4	4	4	128
	Sodium hydroxide	2	1	1	1	2
	Sodium chloride	4	1	1	1	4
	Acetic acid	1	1	1	1	1
Dyes CO	Azo reactive dyestuff preparation a	1	4	4	2	32
	Azo reactive dyestuff preparation b	1	3	4	1	12
	Azo reactive dyestuff preparation c	1	4	4	2	32
After-soaping	Acrylate, sodium salt	2	4	4	4	128
	Acetic acid	1	1	1	1	1
	Mix fatty amide and fatty alcohol ethoxylates	3	1	4	3	36
Score for auxiliaries						457
Score for dyes						104
Total score						561

Note. PES = polyester.

Considering the original motivation for the SC project, the most interesting result from the supporting assessment was that the auxiliary chemicals scored much higher than the dyestuffs. This means that from an ecotoxicity perspective, the choice of dyestuffs was not as important in the LCA as the choice of auxiliary chemicals.

Relating the score system to LCIA

The authors attempted to extrapolate the Score System results to LCIA results and produce an order of magnitude calculation of the toxicity from the wet treatment compared to the total life-cycle toxicity.

The extrapolation, summarized in Table 4, was based on the cotton dyestuff named “azo reactive dyestuff preparation b.” This dyestuff was the only one represented in USEtox and achieved an ecotoxicity score of 5.07e-05 CTUe from USEtox and a score of 12 from the Score System. The USEtox score is 0.005% of the total ecotoxicity score for the cardigan (1.058 CTUe). If 12 points in the Score System are equivalent to 5.07e-05 CTUe (see Table 4), one may hypothesize that the ecotoxicity of the wet treatment wastewater as a whole, if assessed with conventional LCIA, would be about 5.07e-05 ÷ 12*561 = 0.0024 CTUe or 0.22% of the total ecotoxicity score for the cardigan (now increased to 1.0604 CTUe). This share of the total is still quite small if wastewater from the wet treatment process is assumed to undergo mechanical, chemical, and biological treatment, that is, 99% effective at removing excess dyestuff and where the dyestuff has 90% affinity to the cloth (Roos & Posner, 2011). However, without the wastewater treatment plant, the ecotoxicity score for the wet treatment would have represented 18.5% of the total ecotoxicity score (while the total score for the cardigan would increase by 22% to 1.298 CTUe) and thus would have been an issue of high significance.

Table 4.

Extrapolation of Results on Ecotoxicity From the Score System to LCIA Results.

Unit of Analysis	Results for USEtox™ Ecotoxicity (CTUe)	Score System (Points)
Cardigan, initial LCA, 99% effectiveness of WWTP	1.058	Not applicable
Azo reactive dyestuff preparation b	5.07e-05	12
Wet treatment, only impact from chemicals, 99% effectiveness of WWTP	0.0024	561
Cardigan, all wet treatment chemicals included in LCIA, 99% effectiveness of WWTP	1.0604	Not applicable
Wet treatment, only impact from chemicals, no WWTP	0.24	Not applicable
Cardigan, no WWTP	1.298	Not applicable

Note. LCIA = life-cycle impact assessment; CTUe = Comparative Toxic Unit ecotoxicity; WWTP = wastewater treatment plant. Extrapolated results are marked as inclined. A high score indicates high ecotoxicity impact. The metal complexing agent (the alkyl phosphonate, see Table 1) has only a characterization factor in USEtox™ for human toxicity (carcinogen) but not ecotoxicity, so and will does not impact the ecotoxicity score. Acetic acid had has only an interim factor and so it was therefore excluded here from this analysis.

Discussion

Exploring the Limits of LCA in the Textile Sector

We have discussed the challenge of making LCA more relevant for textiles by addressing how chemicals are handled in LCA. In principle, LCA is an attractive method in that it can handle multiple environmental impact categories in a systematic manner. For the textile product group, chemicals represent one of the major areas of environmental concern and should be included in any holistic assessment of environmental impact. The method development for LCIA of chemicals has taken several important steps forward in recent years (Hauschild, Jolliet, & Huijbregts, 2011) but still suffers from weaknesses, which have led to the exclusion of impact from chemicals from most recent textile LCAs. The disregard of chemical issues in sustainability assessments can lead to erroneous conclusions and guide sustainable development in the wrong direction. One example is the recent ranking of conventional cotton as a material of low environmental impact (Muthu, Li, Hu, & Ze, 2012), which did not consider the serious impacts of ecotoxicity from the cotton cultivation. Indeed, several major initiatives for reducing the environmental impact from conventional cotton have been launched, such as the Better Cotton Initiative (n.d.). The importance of including chemicals in LCA has also been reported in studies of other industries, such as the printing industry (Larsen, Hansen, & Hauschild, 2009; Laurent et al., 2012).

The life-cycle perspective can give added value

The first research question examined in this article concerned the importance of the life-cycle perspective in order to avoid improving part of a system in a manner that negatively affects other parts of the system (suboptimization). The question of whether bleached or unbleached nightgowns are preferable from an environmental perspective may instinctively seem easy to answer. Must it not be better to avoid a process involving very reactive chemicals? SC believed this to be true. Put in a life-cycle perspective, however, the question is quite complex, involving issues about the production process, product quality, and lifespan as well as the perceived comfort. Figure 2 exemplifies how impacts from use and emission of chemicals in different phases of the life cycle can be quantitatively related to each other. The environmental performance of hospital garments was found in this study to depend greatly on their lifespan. The lifespan of hospital garments depended in turn on the ability to remove dust and short fibers during scouring but also on the perceptions that staff and patients had of the garments’ comfort and hygienic status. The reduction in lifespan was a difficult factor to measure; the 5% reduction assumed in this study was considered a conservative estimate and was probably larger in reality. This is because the unbleached garments’ perceived hygienic status was lower than that of bleached garments, which can result in them being discarded before the technical service life was reached. In a life-cycle perspective, the addition of a bleaching chemical had no significant negative impact and instead contributed to better environmental performance by prolonging the garment lifespan. By considering the entire product life cycle, the selection of an option minimizing the overall impact from chemicals was feasible. The LCA was able to quantitatively inform SC that their belief was incorrect in this case and in doing so provided a reason to support the purchase of more durable garments, potentially improving SC’s future financial position.

Need to include toxicity in LCA

The second research question concerned the weakness in the currently available LCIA methods regarding toxicity issues, which are crucial for textile products. For the cardigans, in the absence of CFs for textile chemicals, LCA was incapable of informing choices between certain dyestuffs. As the dyestuffs were not covered in the LCIA, both versions of the cardigans presented the same result. However, a supporting assessment that evaluated ecotoxicity via the Score System led to the conclusion that the original question (which dyes to use) was too narrow in scope and was not a critical question on the whole. Unfortunately, such supporting assessments are not commonly applied in LCA studies.

Wet treatment when involving proper wastewater treatment was not found to be a major contributor to the toxicity scores for the hospital garments and was insignificant compared with cotton cultivation. However, in the absence of proper wastewater treatment, the wet treatment would have represented a major contributor to the total toxicity. The quantitative and holistic approach offered by LCA is one reason why it is commonly applied as a tool to identify the improvement potential in the environmental performance of products (i.e., for ecodesign, eco-labeling, and other environmental decision making).

The significance of chemicals in terms of environmental and health impact in a life-cycle perspective is a complex equation in which exposure must be considered in addition to chemical effects such as toxicity, acidification, eutrophication, and even greenhouse emissions from the degradation products (Van Zelm, Huijbregts, & Van de Meent, 2010). Indirect effects can be included from other parts of the chemicals’ life cycle (e.g., the energy consumption and emissions during production). The life-cycle perspective, which we have demonstrated, is very useful here for avoiding the transfer of impacts from one life-cycle phase to another. Other professionals currently use the approach of declaring the presence or absence of regulated substances in the textile production chain (MADE-BY, 2013; SAC, 2012). They do this typically without reporting quantities, whether or not the substances are used in closed systems or otherwise, whether emissions and waste are properly treated, and which substances are used instead of the regulated ones. Neglecting such important environmental aspects makes such approaches less informative as tools for environmental decision making.

A flexible way forward

The potential benefits of holistic evaluations of the environmental performance of textile products suggest the need for a flexible way forward to meet the challenge of considering textile chemicals in LCA. Consistent with the general prescriptions of the International Reference Life Cycle Data System (ILCD) handbook (European Commission, 2010), the key elements include the following: (a) identifying the most significant chemicals in terms of environmental and health impact in the life cycle of textile products, (b) developing the LCIA methods to cover CFs for these chemicals, and (c) including the chemicals both in the life-cycle inventories made by LCA practitioners and in commercial LCA databases.

For LCA of textile products, the Score System allows for a preliminary assessment of the significance of particular wet treatment chemicals to the product life cycle to be made when lack of data prevents the application of models like USEtox for deriving CFs. This alternative may be preferred to grouping related chemicals as proposed in the ILCD handbook, as it allows greater differentiation between chemicals. Extrapolating the results back into a comprehensive LCA on the basis of substances that overlap between methods is one way of compensating for missing LCIA CFs. This approach would allow textile designers and procurers an explicit choice between products based on information on the environmental performance of chemicals.

Conclusions

We have demonstrated that a life-cycle perspective can deliver a comprehensive assessment of the chemical performance of textile products. In the case of two white hospital gowns, LCA was a very useful method for evaluating the environmental impact of switching from bleached to unbleached garments. The counterintuitive finding was that the bleached product had better environmental performance than the unbleached product, because the environmental impact from the bleaching was insignificant with regard to the whole garment life cycle and likely to be compensated by a longer lifespan in the user phase of the bleached garment. We have also demonstrated that the inclusion of toxicity considerations in LCA is likely to affect the result of environmental performance ranking for textile products. In the comparison of dyestuffs for blue cardigans, serious data gaps prevented the evaluation of different dyeing options with standard LCA. The complementary use of the Score System showed the choice of dyestuffs to be less important than the choice of auxiliary chemicals. The recommendations given based on the conclusions are thus to increase the lifespan of the products, optimize the choice of auxiliary chemicals, and assure proper treatment of wastewater in order to effectively reduce the environmental impact from the wet treatment. Avoiding the bleaching step or optimizing the dyestuffs are not effective measures.

We have demonstrated a flexible way forward to meet the challenge of considering chemicals in LCA for textiles. To support this approach in practice, life-cycle inventories made by LCA practitioners and commercial LCA databases need to include the most significant chemicals in terms of environmental and health impact in the life cycle of textile products. LCIA methods need to cover textile-relevant chemicals. With the inclusion of chemical impacts, LCA will become a more relevant tool for textile assessment by providing holistic guidance to environmental decision makers.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

This research has been supported by the Swedish funding agency Mistra, in the Mistra Future Fashion program, which is greatly acknowledged.

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