What is a detergent surfactant chemical AES

A soap-based detergent compared to conventional competition

Transcript

1 I A soap-based detergent compared to the conventional competition Application of the life cycle assessment methodology from a study on behalf of the Federal Environment Agency on the eco-washing powder SODASAN Diploma thesis to obtain the degree of economist from the Department of Economics at the University of Hanover

2 II Author: Andrea Strangfeld born on in Hameln Examiner: Prof. Dr. Udo Müller Department of Regulatory and Process Policy Institute for Economics Hanover, July 1997

3 III TABLE OF CONTENTS LIST OF ABBREVIATIONS III LIST OF TABLES V 1 PRELIMINARY REMARKS On the subject: Detergents About work: Reason and objective 2 2 DETERGENTS HOW THEY WORK AND WHAT THEY ARE COMPOSED OF The washing process Detergent ingredients Surfactants Softeners and 3 Bleaching agents Detergent types Detergent additives AND EVALUATION OF THE ENVIRONMENTAL EFFECTS OF DETERGENTS Introduction to the life cycle assessment instrument Structure of a life cycle assessment 20 4 THE STUDY ON ORDER OF THE ENVIRONMENTAL OFFICE HOW WAS PROCEDURE? Objective and scope of investigation Underlying preliminary studies Surfactant study Packaging Production of the packaging Procedure for the preparation of the life cycle assessments Methodology of the impact assessment Selection of the environmental impact categories Greenhouse effect Acidification Photosmog Methodology of the evaluation 47

4 IV 5 THE ECO DETERGENT SODASAN WHAT IS THE DIFFERENCE TO CONVENTIONAL DETERGENTS? 50 6 IMPLEMENTATION OF THE ECOBALANCING OF THE SPECIFIC COMPARISON Assumptions in the assessment of SODASAN Life cycle assessments Overview of the life cycle inventory results of the study Determination of the relevant emissions carbon dioxide, nitrous oxide and methane Sulfur dioxide, nitrogen oxides, chlorine and hydrogen fluoride hydrocarbons Impact assessment Evaluation Evaluation according to environmental targets Impact assessment according to ecological targets Reason and procedure Explanation of the criteria Results 80 7 FINAL ANALYSIS OF THE LCA HOW EFFECTIVE ARE THE RESULTS? 83 8 CONCLUDING REMARKS 86 TABLE OF CONTENTS OF THE APPENDIX 90 APPENDIX 91 LITERATURE 119 DECLARATION 129

5 V LIST OF ABBREVIATIONS AE see FAE AES Alcohol Ethoxy Sulphates Note d. V. Note of the author APE Alkylphenolethoxilat APG Alkylpolyglucoside / Alkyl Polyglucosides APME Association of Plastics Manufacturers AS see FAS AW Exclusion value BOD Biological oxygen demand SAEFL Federal Office for Environment, Forests and Landscape CEFIC European Chemical Industry Council CMC Carboxylmethylcellulose CML Centrum voor Milieukunde Leiden d. d. V. by the author ie degree of German hardness DIN German Institute for Standardization ibid. Ibid. EC Middle Concentration Effect ECOSOL European Center of Studies on Linear Alkylbenzene EDTA Ethylenediamine tetraacetate EMPA Eidgenössische Materialprüfungsanstalt FAL Franklin Associates Limited FAE Fettalkohol-Ethoxilate / Alcohol Ethoxylates FAS Fettalkohols Sulphates CFCs Chlorofluorocarbons GEMIS Overall emissions model of integrated systems GF Weighting factor H. d. d. V. Emphasis by the author IKW Industrieverband Körperpflege- und Waschmittel e. V. i. S. in the sense of ISO International Standardization Organization k. A. not specified KF correction factor KVV TOX critical dilution volume LAS linear alkylbenzenesulfonate / linear alkylbenzene sulfonates LC mean lethal concentration LZF long-term consequences MJ megajoules n.a. d. V. according to the author NAGUS Standards Committee Basics of Environmental Protection NMVOC Non-Methane Volatile Organic Compounds

6 VI NOEC No Observable Effect Concentration o. V. without author Pc Petrochemical P MAX Maximum achievable number of points PVP Polyvinylpyrrolidone SAS Secondary Alkane Sulphonates SETAC Society for Environmental Toxicology and Chemistry TAED Tetraacetyl-ethylenediamine ThSB Theoretical oxygen demand UBA Umweltbundesamt VOC Volatile Organic Compounds WID -Database

7 VII LIST OF TABLES Table 1: Detergent components 4 Table 2: Examined detergent variants 27 Table 3: Model formulations 28 Table 4: Raw material bases used 31 Table 5: Data bases for packaging 34 Table 6: Data bases for the manufacture of packaging materials 37 Table 7: Substance-related emissions -Reduction targets of the Federal Republic of Germany 40 Table 8: Environmental impact categories and weighting factors 41 Table 9: Formulations of the components in the SODASAN modular system 50 Table 10: Determination of the overall formulation of the SODASAN modular system 54 Table 11: Life cycle inventory values ​​of the Öko-Institut study 56 Table 12: Determination of the N 2 O emissions for var. A 57 Table 13: Determination of the CO 2 emissions for Var. A 59 Table 14: Determination of CO 2 emissions for SODASAN 61 Table 15: Determination of N 2 O emissions for SODASAN 62 Table 16: Determination of methane emissions for SODASAN 63 Table 17: Determination of SO 2 emissions for SODASAN 65 Table 18: Determination of NO X emissions for SODASAN 66 Table 19: Determination of ClH emissions for SODASAN 67 Table 20: Determination of FH emissions for SODASAN 68 Table 21: Determination of VOC emissions for SODASAN 69 Table 22: Corrected or . Recalculated inventory inventory values ​​70 Table 23: Greenhouse effect potential of the variants 72 Table 24: Acidification potential of the variants 72 Table 25: Photosmog formation potential of the variants 72 Table 26: Evaluation parameters as equivalents 73 Table 27: Effect potentials of SODASAN with changed dosage 74 Table 28: Overview of the evaluation system of the EC eco-label for detergents 77 Table 29: Point distribution of the variants according to the evaluation system of the EC eco-label s for detergent 80

8 1 1 PRELIMINARY REMARKS 1.1 On the subject of detergents The high dynamism of the Central European detergent market was particularly evident in the area of ​​advertising in recent years. A good ten years ago the marketing concepts of the major manufacturers were still able to convince consumers with incentives such as super white and not just clean, but pure, today the criterion of cleanliness is no longer the only concern. 1 As in almost every branch of the economy, advertising strategies today include the ecological quality of one's own product, since the changed environmental awareness of consumers and the opportunities associated with it have not remained hidden to companies. 2 In other words, competition today is on the ecological front. 3 Whether corresponding advertising messages really play a decisive role in buying a product or just represent an additional benefit for the consumer that has become a matter of course depends, among other factors, on how good the knowledge is about the environmentally relevant data 4 of different detergents. Eight years ago, in the summer of 1989, the effects of pollution in the North Sea could not be overlooked: on the island of Amrum, for example, seal deaths and algae carpets led to the spontaneous abandonment of phosphate detergents by retailers; a year later, phosphates were generally no longer used as detergent ingredients in Germany. However, not all environmental degradation is so obvious. Biodegradability 5 of the detergents on the market and the efficiency of modern sewage treatment 1 The partial change in consumer preferences is certainly also due to the fact that the criterion of cleanliness (which is still required) is not an absolute, but a subjective variable, which is based on the average perceptions of society and can possibly change, for example through increased environmental awareness. 2 Cf. Hallay / Pfriem 1992, p. 7 3 J. Jobs, cited in Biester 1993, p. Environmentally relevant data can describe positive and negative material properties. These properties trigger effects for which a large number of terms are used in language (environmental effects: cf. Müller-Wenk 1992 a, p. 9; environmental influences: cf. Corino 1995, p. 10; environmental pollution: cf. Ahbe et al. 1990, p. 3) is used. 5 The concept of biodegradability is explained in chapter in the course of the treatment of detergent ingredients.

92 were so advanced that there were hardly any changes that were noticeable to the consumer. Nonetheless, these changes in the natural state take place; an ecologically completely intact body of water can hardly be found in Lower Saxony, for example. 6 Instead of waiting until the problems become difficult or irreparable, an attempt can be made, with the help of scientific statements about the material composition and effect of the multi-substance mixtures 7, to prepare detergents before harmful chemicals are released. Science is working on environmental information systems with as comprehensive and communicable assessment procedures as possible that provide information about the possible consequences of using a detergent. They can be the basis for legal provisions, for voluntary industrial agreements and also for concrete advice and behavioral recommendations for environmentally conscious consumers. In the case of the Federal Environment Agency commissioned by the Öko-Institut e. V. study, product line analysis for laundry and detergents, is one such approach. 1.2 About the work: Reason and objective Due to its topicality (it was published at the end of 1996 by the Öko-Institut and at the beginning of 1997 by the Federal Environment Agency), the above-mentioned study by the Öko-Institut Freiburg provides an opportunity to use the tool at hand and in the area of ​​the highly dynamic detergent market , which is subject to constant raw material and product developments. The Öko-Institut study relates to a cross-section of marketable products, with the model recipes being based on weighted mean values. The result is an evaluated comparison of different detergent concepts or detergent types, not a recommendation of individual products. The present work has obviously set itself the goal, after an introduction to the topic of detergent chemistry and a presentation of the methodology of life cycle assessments in general and in particular 6 According to the environmental report of the Lower Saxony state government, no surface water in Lower Saxony can claim quality class I (unpolluted). The desired quality class II (moderately polluted) applies to 25% of the bodies of water (see Lower Saxony Ministry of the Environment 1994, p. 82). 7 See Grießhammer et al., P. 1

10 3 apply this developed methodology to a specific product. 8 In this case, the project is particularly suitable because the SODASAN detergent under consideration is one of the detergent concepts included (it is a modular system), but its composition differs significantly from the articles otherwise offered on the market. The SODASAN modular system is one of the so-called eco or alternative detergents. These stand out from conventional products both in terms of the type and number of ingredients and in their advertising, which is designed with a different focus, and thus make greater demands on compatibility, especially from an ecological point of view. This work should determine whether and to what extent SODASAN can meet this requirement within the applied evaluation system. 8 Such use of the developed methodology in the form of testing and evaluation of individual products by test organizations was expressly requested in the preliminary study of the Öko-Institut study (cf. Grießhammer et al., Volume 1, p. 290).

11 4 2 DETERGENTS HOW THEY WORK AND WHAT THEY ARE MADE OF 2.1 The washing process According to the Sinner wash cycle, the four factors temperature, mechanics, time and chemistry are decisive for the cleaning process. 9 If the use of one factor is reduced, it can be substituted by the other factors up to a certain point. The first three factors are limited potentials, the significant increase of which is not possible or not desired. So chemistry, i.e. the use of detergents, remains a regulating factor. Detergents consist of a large number of ingredients that are precisely matched to one another. The exact formulations of the products are not published by the detergent manufacturers, but must be deposited with the Federal Environment Agency. 10 For a better overview, all ingredients can be classified according to the following table: Active substances Filling substances Surfactants Adjusting agents Softeners Bleaching agents Auxiliary substances Table 1: Detergent components (source: own illustration) The detergent and therefore the most important substances in a formulation are surfactants. They are active where water alone cannot loosen the dirt. In cleaning and hygiene technology, dirt is understood to mean material in the wrong place. Dirt in the laundry is almost always a question of greasy compounds that come from the skin, from foodstuffs. 9 Cf. Stache / Großmann 1992, pp. 15f 10 The database at the Federal Environment Agency contains current general formulations for detergents and cleaning agents (including approx 700 household washing (auxiliary) medium) (cf. Grießhammer et al., P. 27).

12 5 residues or kitchen fumes, come from oily machines or oily car exhaust fumes. 11 It forms the breeding ground for microorganisms of all kinds. Surfactants are surface-active because they accumulate where water and oily components come into contact with one another. This is possible due to the molecular structure with a hydrophilic (water-friendly) and a lipophilic (oil-friendly) part. Surfactant molecules slide under unwanted substances such as oil and grease dirt and remove them from the fiber surfaces. This process is favored by the lowering of the surface tension of the water: This means that surfactant solutions can more easily penetrate the fiber and wet all surfaces. The dirt removed from the fiber and coated with surfactants takes on the energetically favorable spherical shape; the fine distribution of these dirt droplets in the water is known as dispersion. The surfactant film that is deposited on the fiber surface during the washing process cannot, however, be completely removed even by subsequent rinsing and drying, so that constant direct skin contact with surfactants is practically unavoidable. 12 Depending on the electrical charge of the hydrophilic group of a surfactant, a distinction is made between cationic, anionic, nonionic and amphoteric surfactants (which have differently charged groups). This declaration on the packaging only makes a statement about the way in which the washing-active substances dissolve in the water. Anionic and nonionic surfactants in particular are used in detergents and cleaning agents. Fabric softeners and disinfectants contain i. d. R. cationic surfactants. Surfactants can be produced on a petrochemical basis (petroleum) or based on animal or vegetable fats and oils. Accordingly, they are natural, synthetic or semi-synthetic surfactants. After the basic mode of action of the washing-active substances has been explained, the following deals with the most important detergent components in detail, with a brief assessment of their previously researched effects on the environment. After these preliminary considerations, the various detergent concepts currently on offer are presented. 11 See Herrmann et al. 1985, S cf. Herrmann et al. 1985, p. 55; Biester 1993, p. 42

13 6 2.2 Detergent ingredients Surfactants Soap made from vegetable ash and oils was already in use 2500 BC. Known 13 BC and was used as a cleaning agent in the second century AD at the latest. 14 The production methods changed well into the 19th century, when the introduction of the industrial production of the required soda (sodium carbonate) meant a great qualitative and quantitative advance for soap production. Soap is an anionic surfactant made from animal or vegetable fats and oils. For the chemist, soap is an alkali salt of higher fatty acids, i.e. a sodium or potassium salt with at least eight carbon atoms. 15 The necessary fatty acids (carboxylic acids) are released from fats and sodium or potassium hydroxide in a boiling process. They are usually neutralized with soda (dissolved: caustic soda / caustic soda 16). 17 The solid sodium soaps are the well-known curd soaps and are used for laundry cleaning. We know the pasty potassium soaps as soft soap. One of the disadvantages of the soap is its high sensitivity to hardness. 18 From approx. 10 dh (middle of hardness range 2) the carboxyl group of the soap is blocked by calcium and magnesium ions and the formation of insoluble lime soap, which has no detergency. 19 It can be deposited as an incrustation on textiles and machine parts. This process can be prevented with the help of softeners (see chapter 2.2.2). 13 See Kosswig / Stache 1993, p. 118; Brüschweiler et al. 1988, S cf. Stiftung Consumer Institute 1988, S cf. Herrmann et al. 1985, S cf. Siekmann 1987, keyword caustic soda 17 cf. Postlethwaite 1995, S Water hardness is measured in the proportions of alkaline earths (calcium and magnesium ions). These salts are absorbed by rainwater when they seep into the ground. Soils containing lime, dolomite, limestone or gypsum are responsible for high water hardness. The cations deactivate part of the active washing substance because they combine with the anion surfactants such as soap to form sparingly soluble salts. In addition, the tissue can turn gray and crusty.However, this phenomenon can also occur with soft water, since the laundry soiling can change the washing solution accordingly (cf. Stache / Großmann 1992, p. 27f; Vollmer / Franz 1994, p. 31). 19 See Foundation Consumer Institute 1988, p. 61

14 7 The property of forming lime soap is also to be assessed positively from an ecological point of view. When the soap enters the wastewater, it reacts with the salts and acids that are present to form lime soap and fatty acids, both of which are insoluble and not surface-active. 20 Later there is a decomposition process by the microorganisms living in the wastewater (total breakdown or mineralization 21) with the products water, carbonic acid and, in neutral wastewater, sodium hydrogen carbonate. 22 Fatty substances, as found in soap and lime soap, are also components of living cells and metabolic products of the microorganisms responsible for degradation and therefore have no adverse effects on sewage and water. 23 Soap is 80% removed in 24 hours and 99% in about three days. 24 However, the rate of degradation also depends crucially on the soap concentration and the type of fatty acids. Analytical laboratory tests have also shown that synthetic surfactants can degrade just as quickly as soap. 25 When assessing biodegradability using laboratory tests, account should always be taken of where the degradation takes place. Regardless of the above-described decomposition process by microorganisms in the wastewater, the formation of lime soap also means that 60-70% of the surfactant can settle in the primary treatment and is removed with the sewage sludge. 26 The anaerobic degradation thus takes place in the sewage treatment plant. 27 Another advantage of the formation of lime soap is its moisturizing effect on textiles; the fiber is not completely degreased and thus dull, as is the case with synthetic surfactants, but remains slippery, so that the 20 Cf. o. V a, p. 27; Lutz 1990, S Total degradation or mineralization means the conversion of the intermediate substances into the end products H 2 O, CO 2, phosphates and sulfates with the help of oxygen (cf. Lutz 1990, p. 42; Herrmann et al. 1985, p). 22 See Herrmann et al. 1985, S cf. Brüschweiler et al. 1988, pp. 306f; Brüschweiler et al. 1991, p. 354; Consumer Institute Foundation 1988, p. 92; Semolina hammer and others 1984, S cf. Herrmann et al. 1985, S cf. Brüschweiler et al. 1988, S cf. Dorgeloh 1994, S While aerobic degradation takes place with the aid of oxygen, anaerobic degradation takes place with exclusion of oxygen during sewage sludge treatment in the digestion tower. If there is no anaerobic degradability, surfactant residues remain in the agricultural sewage sludge (cf. Lutz 1990, p. 42).

15 8 set of fabric softeners becomes superfluous. 28 Compared with synthetic surfactant mixtures, soap usually has to be dosed higher for a comparable washing result. 29 In contrast to synthetic surfactants produced on a petrochemical basis, soap production is based on natural, renewable raw materials. Mainly coconut and palm kernel oil are used. An assessment must take into account the extent of the cultivated areas and the ecological effects of the monocultures, but should not be pursued further at this point. The shortage of fat, which occurred especially during the two world wars, led to the search for synthetic alternatives, i.e. detergents whose raw materials were petroleum and hard coal. 30 These inexpensive substances were initially mixed with the expensive soap, later they replaced it entirely. An example of a detergent surfactant based only on petroleum is APE (alkylphenol ethoxylate). Its highly branched synthetic chains are poorly biodegradable, which has already led to a ban or restriction in various countries. In Germany, the Aldi Group was the last major user of the APE with the heavy-duty detergent Tandil. 31 In 1986 the industry associations entered into a voluntary agreement with the Federal Ministry to renounce APE. 32 LAS (linear alkylbenzene sulfonate 33), which has been the world's most important surfactant for years due to its low price and very good detergency, is a synthetic anionic compound and is also based on petroleum. It shows good foaming ability, and a high level of stabilization can be achieved by foam stabilizers. On the other hand, the unbranched (linear) LAS molecule can also easily be replaced by foam- 28 Cf. Projektgruppe Ökologische Wirtschaft 1987, p. 102; Herrmann et al. 1985, p. 64; The effect described is, however, controversial: According to Lutz, the softening soap residues should be completely removed when modern washing machines are used with several rinses (cf. Lutz 1990, p. 151). 29 Cf. Grießhammer et al., Volume 2, pp. 231f 30 Cf. Herrmann et al. 1985, pp. 61f 31 Cf. Herrmann et al. 1985, p. 71f 32 Lutz 1990, p. 46; Stache 1990, S The abbreviation LAS is also given in the literature with lauryl alkyl sulfonate (cf. Dorgeloh 1994, p. 49).

16 9 control gulators, 34 so that the introduction of the LAS contributed to the disappearance of the foam mountains on the rivers. 35 In the sewage treatment plant, 73 to 93% of LAS is broken down 36 and thus fulfills the requirements of the detergent law. However, this (partial) degradation 37 takes place significantly more slowly than with other surfactants. In contrast to soap, LAS is not anaerobically degradable, but remains in high concentration in the sewage sludge. 38 LAS is also sensitive to hardness, but less so than soap. 39 The Öko-Institut Freiburg assesses the LAS concentrations occurring in the waters as intolerable. 40 The also anionic FAS (fatty alcohol sulfates) can demonstrate better biodegradability. They are obtained through a reaction of fatty alcohols with sulfuric acid and its derivatives. If such fatty alcohols are used, which are obtained from natural animal and vegetable fats and oils, FAS belong to the semi-synthetic surfactants. Both the primary and the total degradability of these compounds are good. 41 On the other hand, the less common FAS obtained from petroleum is one of the fully synthetic surfactants. FAS have been used in liquid detergents for a long time, while they have only been used in washing powders since 1993. Due to their good (also anaerobic) degradability, the renewable raw material base and a low-energy production, they will increasingly compete with the LAS. 42 However, the poor skin tolerance of FAS is to be assessed negatively. Cf. Jakobi / Löhr 1987, S Cf. Herrmann et al. 1985, S Brodersen / Duve 1989, p. 84; Lutz 1990, p. 43; Herrmann et al. 1985, S In the detergent law of, it is required that 80% of the surfactants must have lost their surface-relaxing effect within three weeks. However, this primary degradation only means the loss of the foaming capacity. Total degradation to environmentally compatible substances (mineralization, see footnote 21) is not required. Accordingly, advertisements such as biodegradable or 100% degradable do not guarantee good environmental compatibility, but only mean partial degradation with e.g. End products that are partly difficult to break down and which are not broken down (Herrmann et al. 1985, p. 37f; more precisely also Stiftung Consumer Institute 1988, p. 72) 38 Lutz 1990, p. 43f; Dorgeloh 1994, p. 50; Brüschweiler et al. 1991, p. 352; Consumer Institute Foundation 1988, S Consumer Institute Foundation 1988, S Cf. Grießhammer et al., P. 292; Grießhammer 1993 a, S Cf. Herrmann et al. 1985, p. 68; Lutz 1990, S Upadek / Krings 1991, S Lutz 1990, pp. 44f

17 10 FAE (fatty alcohol ethoxylates) belong to the class of nonionic surfactants. They are also produced partly synthetically: the fatty alcohol components are of natural origin, while ethylene oxide is obtained from petrochemicals. FAE connections come in many different variations. The types used in household products are primarily degradable and mineralizable. They are also suitable for anaerobic degradation. 44 Further advantages are the low sensitivity to hardness and the good skin tolerance. The detergency is generally good, especially at higher temperatures. 45 A clear minus point of the FAE, however, is the high dosage of the highly toxic and carcinogenic gas ethylene oxide in the conversion of fatty alcohols to ethoxylates. 46 The Öko-Institut study is based on the compound AE 7 Pc, a petrochemical alcohol ethoxylate with an ethylene oxide chain length of seven. 47 Finally, a very new development among the surfactant classes should be mentioned. APG (alkyl polyglucosides) are produced exclusively from natural raw materials, 48 ​​namely through the condensation of fatty alcohols with glucose or starch. 49 Like all nonionic surfactants, they are relatively insensitive to hardness and, especially in combination with other surfactants, have a satisfactory washing performance. In addition, they are completely biodegradable, non-toxic and skin-friendly. With the development of economical manufacturing processes in recent years, competitive prices and, ultimately, wider use can be expected. Softeners 51 As already mentioned, the effectiveness of some surfactants decreases with increasing hardness of tap water. For this reason, softeners are used, which bind the ions dissolved in the water and thus reduce the hardness of the water. In addition, they facilitate the removal of dirt by removing calcium and 44 Lutz 1990, S cf. Kosswig / Stache 1993, s cf. Project Group Ecological Economy 1987, p. 102; Herrmann et al. 1985, S cf. Schul et al. 1995, S cf. Lutz 1990, S cf. Upadek / Krings 1991, S cf. Andree / Middelhauve 1991, S Softeners are also referred to as builders, builders or complexing agents.

18 11 Remove magnesium compounds from the dirt and break it open. 52 Phosphates (salts of phosphoric acid) meet both requirements excellently. Sodium triphosphate, which has been used exclusively for a long time since 1960, is also non-toxic. Up to 1981 it was contained in detergents with up to 40%. 53 However, a change became necessary, as phosphates are excellent plant nutrients and, when exposed to high levels, lead to eutrophication 54 of the waters. The inorganic phosphates cannot be broken down in conventional sewage treatment plants; a third, chemical cleaning stage is required. 55 It is certainly more sensible to forego the addition of phosphate in detergents, as it is e.g. B. is practiced in Germany, Switzerland, the Netherlands, Belgium, Norway and Austria. In France and Spain, however, phosphate is still used. 56 One of the most important substitutes is the synthetic sodium aluminum silicate, better known under the name Zeolite A (trade name Sasil). The water is softened by an ion exchange: hardness-forming calcium and magnesium ions are absorbed from the lye, and non-hardness-forming sodium ions are released into it. 57 Zeolites have the character of a sand and are insoluble. 58 Approx. 96% of them are eliminated via the mud path 59 and slowly converted to silica. 60 Since zeolites do not have the advantages of triphosphate with regard to the washing-promoting effect, they are i. d. Usually combined with polycarboxylate and soda (sodium carbonate) (so-called co-builders). 61 The former is due to its relative 52 Cf. Vollmer / Franz 1994, S Cf. Stache / Großmann 1992, S Eutrophication is the nutrient oversaturation of waters through fertilizers such as phosphates and nitrates with the accompanying overproduction of organic matter. After the dense aquatic plant population has died off due to a lack of light, the degrading microorganisms consume a lot of oxygen and thus a lack of oxygen, especially in stagnant water. Aerobic degradation is followed by anaerobic degradation with poisonous decomposition processes (overturning of a body of water) (cf. Reader et al. 1993, keyword eutrophication; Vollmer / Franz 1994, p. 41f; Grießhammer et al. 1984, p. 79). 55 Cf. Consumer Institute 1988, pp. 95ff. 56 Cf. Upadek / Krings 1991, p. 556; Grießhammer et al., S cf. project group ecological economy 1987, S cf. Herrmann et al. 1985, p. 85f 59 cf. Dorgeloh 1994, S cf. Stiftung Konsuminstitut 1988, S cf. Upadek / Krings 1990, p. 557

19 12 poor biodegradability is discussed, but is largely eliminated with the sewage sludge and is not toxic. 62 Even as an inorganic compound, soda is not degradable, but neither does it contribute to the fertilization of water bodies. 63 Trisodium citrate, on the other hand, is readily degradable, 64 a citric acid salt obtained from sugar, which is an important link in the metabolism. It is also suitable at low temperatures, but there is a loss of effectiveness with hot laundry. The high dosage required and the rather high price are disadvantageous. 65 Sodium layered silicates are a rather new development. 66 They support softeners and surfactants and can also act as softeners themselves. However, these compounds have proven to be unstable from a washing temperature of approx. 60 C. The combination of silicates with zeolite is therefore recommended. 67 The combination of silicates with soda also achieves good washing results. 68 Overall, no negative environmental effects are known about the silicates that release silica in the waste water. Bleaching agents Soiling that cannot be washed out by the surfactants is removed with a bleaching agent through chemical oxidation. 70 This process has replaced the previously common lawn and sun bleaching. This is a color-destroying process by active oxygen, which is released from oxygen-containing chemical compounds. 71 Today, sodium perborate is mostly used in laundry detergents. After the oxygen has been released, borate remains in the wash liquor, a 62 ibid .; Consumer Institute 1988, S ibid., S ibid .; Upadek / Krings 1990, S cf. Herrmann et al. 1985, S Cf. Upadek / Krings 1990, S Cf. ibid. 68 Cf. Project Group Ecological Economy 1987, S Cf. Herrmann et al. 1985, p. 92; Stache / Großmann 1992, S B. dyes from fruit, carrots, tomatoes, curry and mustard, tannins from tea, red wine and fruit and humic acids from coffee, tea and cocoa (cf. Stache / Großmann 1992, p. 68) 71 cf. Stache / Großmann 1992, p 104

20 13 Substance that passes through sewage treatment plants unchanged and ends up in water bodies. The concentrations measured so far appear to be relatively low. There is still no consensus on the ecological effects of boron. Its use over the past 80 years has been assessed on the one hand as being free of negative consequences, 72 on the other hand there is increasing reference to the unfavorable effects of even low concentrations of borate ions on the flora and fauna of the water. 73 When the EC eco-label is awarded to detergents, sodium perborate is assessed negatively because of its toxicity and its inorganic character. 74 Another disadvantage of sodium perborate is its instability, which is counteracted by EDTA (ethylenediamine tetraacetic acid), which is also controversial because of its poor degradability. 75 However, the use of these bleach-stabilizing components (phosphonates are also used) is declining; alternatives are currently being researched. EDTA, for example, is no longer used in any household detergent in Germany. 76 Finally, it should also be mentioned that sodium perborate alone only works from approx. 70 ° C., so that the bleaching effect can only be achieved at lower temperatures with the addition of so-called bleach activators. At the moment TAED (tetraacetylethylenediamine) is mainly used. Due to its good degradability and non-toxicity, TAED is classified as harmless. 77 An alternative to sodium perborate is available with sodium percarbonate. Because of the lack of borate pollution and its effectiveness even without an activator, it is considered more environmentally friendly. 78 Sodium percarbonate also has to be stabilized as a component of a washing powder, but either the harmless magnesium silicate is used 79 or the bleach additive is offered separately in the so-called modular systems, which eliminates the problem of storage stability. 72 Cf. Upadek / Krings 1991, S Cf. Stiftung Consumer Institute 1988, pp. 127 and 129; Lutz 1990, p. 57; Brodersen / Duve 1989, p. 84f; Herrmann et al. 1985, p. 101; Project group ecological economy 1987, p. 104; Grießhammer et al. A b, S cf. part 2 of the evaluation system of the Öko-Institut study, presented in chapter cf. consumer institute foundation 1988, pp. 127 and 129; Lutz 1990, S Bgl. Upadek / Krings 1991, S cf. Stache / Großmann 1992, p. 109; Dorgeloh 1994, S cf. Consumer Institute Foundation 1988, p. 128f; Herrmann et al. 1985, p. 102; Ecological Economy Project Group 1987, S cf. Stiftung Consumer Institute 1988, p. 128

21 Auxiliaries and fillers Enzymes 80 are added to detergents in small quantities as biocatalysts to break down water-insoluble, protein-containing soiling. The types of enzyme used are grown in tanks from microorganisms such as bacteria or yeasts. Due to their allergenic effect in detergent production, they are now processed as granules. The enzymes can only work optimally at temperatures between 50 and 70 C; at higher temperatures they are destroyed. As a component of living cells, the degradability of the enzymes can be described as good. They are suitable for both aerobic and anaerobic degradation. 81 In order to increase the whiteness of freshly washed laundry, optical brighteners are used, which are also found in almost all new items of clothing.They do not contribute to the cleanliness of the laundry. The dermatologically controversial 82 compounds draw on the fiber and transfer part of the invisible ultraviolet daylight into visible light. 83 However, some of them end up in the wastewater, where they are only very slightly biodegradable. 84 Graying inhibitors (especially carboxylmethyl cellulose, CMC) are supposed to bind the dirt loosened in the washing process and keep it finely distributed in the washing liquor. CMC is poorly degradable, 85 but almost completely settles in the sewage sludge and is considered to be ecologically harmless. 86 The same applies to sodium silicate, which serves as a corrosion inhibitor. It accumulates on metal surfaces, thus protecting them from the lye and under- 80 Since the beginning of the nineties, almost all detergents contain enzymes that are grown from genetically modified microorganisms, although there is no corresponding information on the packaging. The Öko-Institut Freiburg points out that the consequences of the release of these living, manipulated organisms are still unexplained (cf. o. V b). The federal government does not rule out health risks either (see above 1994). 81 See Lutz 1990, pp. 134f; Dorgeloh 1994, p. 53; Berg et al. 1976, S The assessments range from harmless (Stache / Großmann 1992, p. 73) to the dangers attributed to optical brighteners such as the development of cancer and allergic eczema, dermatoses, mutations and others. (Herrmann et al. 1985, p. 106; also Lutz 1990, p. 136). 83 See Stache / Großmann 1992, p. 73; Jakobi / Löhr 1987, S cf. Dorgeloh 1994, S cf. Dorgeloh 1994, S cf. Projektgruppe Ökologische Wirtschaft 1987, p. 105; Stache / Großmann 1992, p. 112

22 15 also supports softeners and surfactants in their effectiveness. 87 PVP (polyvinylpyrrolidone) is used as a color transfer inhibitor in color detergents. 88 foam regulators are designed to prevent the washing machine from foaming over. The soaps 89 previously used for this purpose in heavy-duty detergents were, however, i. d. Usually replaced by silicones and paraffins. 90 fragrances and dyes also have no effect on the washing result. The composition of the substances used is largely unknown, so that no statements can be made about degradability and risks. 91 Sodium sulphate (Glauber's salt) and (more rarely) soda or table salt are used only as fillers or thickeners in powder detergents. The proportion of these substances in detergents is 10 to 50%. In addition to the endeavor to give the products the psychologically correct weight, the reasons lie in ensuring good flowability, dosability, solubility and storability. The use of sodium sulphate is particularly worrying because it results in the salination of water. Detergent types 93 At present, heavy-duty detergents, also known as all-purpose detergents, dominate the detergent market. They contain all of the components listed in Table 1, i.e. surfactants, softeners, bleach additives, auxiliaries and, if applicable, fillers. The consumer does not have the opportunity to use the individual components as required; he only doses the total amount according to the hardness of the tap water and the degree of soiling of the laundry. Heavy-duty detergents can be used at temperatures up to 95 C. The advantage is that it is easy to use. The disadvantages, however, are obvious: Especially with high water hardness and a correspondingly high dosage of the entire recipe, there is an overdosage of the next 87 See Project Group Ecological Economy 1987, S Cf. Grießhammer et al., S Cf. Kosswig / Stache 1993, S Vg. Lutz 1990, p. 137; Upadek / Krings 1991, S Vg. Ibid .; Herrmann et al. 1985, p. 108ff 92 Cf. Project Group Ecological Economy 1987, p. 105; Lutz 1990, p. 134

23 16 chemicals contained in the required softener. In these cases, some of the surfactants are therefore given unused into the wastewater. Bleach additives are even unnecessary in most washes as they are only used for stubborn stains. Colored laundry finally loses its color intensity due to the use of optical brighteners. Delicates and colored detergents, on the other hand, do not contain any bleach additives or optical brighteners and are therefore more environmentally friendly. Instead, they contain color-retaining and color-enhancing substances. The development of liquid detergents meant a step forward. They contain water as a filler and can be dosed less because they have a higher surfactant content. In addition, they do not contain bleach either. 94 Heavy-duty and colored detergents have also been available as so-called compact detergents 95 (compacts) since 1989. These powder concentrates are characterized by their high packaging and space-saving liter weight. 96 They only contain active ingredients; filling substances are completely dispensed with. The ingredients are roughly the same as in the conventional variants, but perborate monohydrate is used as a softener, which is 50% more effective than the usual tetrahydrate. 97 Finally, the so-called super concentrates (Megaperls), which have been available since 1994, should also be mentioned. The principle of the modular system enjoys the best reputation among detergent concepts in terms of environmental pollution. 98 It consists of three components that are offered and stored separately: basic detergent, softener and bleach additive. The first two components correspond to a color detergent, all three together to a heavy-duty detergent. With this principle, some ingredients can be dispensed with. 93 Cf. in the following Vollmer / Franz 1994, p. 36ff; Project group ecological economy 1987, p. 106f; Lutz 1990, S cf. Brodersen / Duve 1989, pp. 92f 95 Due to their advantages, compact detergents had already captured a market share of 63% (including superconcentrates) in 1995; Standard powders were 29%. Unfortunately, however, there has been a trend reversal in the meantime, recognizable by the frequent special offers and the corresponding increase in sales (plus of 3% in 1995) of the conventional 10 kg packages. It remains to be seen whether the responsibility lies with the manufacturers, retailers or consumers (cf. Knöfel 1997; o. V a). 96 Cf. Upadek / Krings 1991, S Cf. ibid.

24 17, for example to bleach-stabilizing substances, others are replaced by compatible alternatives. 99 However, the lower environmental impact due to saved or more compatible chemicals is offset by a greater amount of work in the household: the items to be washed must be sorted more carefully, and the detergent dosage must be changed from wash to wash according to the respective requirements. The fabric softeners are not detergents in their own right, but laundry post-treatment agents; For the sake of completeness, however, they should be mentioned briefly. They are mostly used after the use of synthetic surfactants, which strongly degrease the fiber. They draw on the fiber and smooth it. The residues of the cationic surfactants on clothing, however, are said to have dermatologically damaging effects and, moreover, are hardly degradable; however, they form insoluble compounds with the anionic surfactants in detergents and are largely eliminated from the wastewater with the sewage sludge. Cf. Lutz 1990, p. 147; Project group ecological economy 1987, p. 106f; Brodersen / Duve 1989, S Sodium perborate is replaced by sodium percarbonate, phosphate by zeolite or citrate. In addition, the soap is being used more and more again. On auxiliary materials i. d. Usually completely omitted (more details in Chapter 5 in the explanation of the composition of the modular detergent SODASAN). 100 See Herrmann 1985, p. 113ff; Project group ecological economy 1987, p. 105f

25 18 3 THE LCA - AN APPROACH TO DETERMINE AND EVALUATE THE ENVIRONMENTAL EFFECTS OF DETERGENTS 3.1 Introduction to the life cycle assessment tool As was made clear in the previous chapter, the ingredients of detergents can significantly change the room in which they are dispensed. This becomes particularly clear when one takes into account the annual quantities used: The consumption of tensides alone in Germany in 1990 in household detergents and cleaning agents amounted to tons. 101 All the more important for product policy control on a legal or voluntary basis, as already mentioned in Chapter 1.1, are meaningful environmental information systems that convey knowledge about the ecologically best variants. The life cycle assessment is one of the available environmental information systems. At the Midwest Institute in Kansas City, what was probably the first life cycle assessment was carried out on behalf of Coca-Cola in 1969. 102 In the following years of constant further development, there were agreements regarding the structure of the balance sheet and the design of some balance sheet components, but there are currently no generally accepted conventions for the balance sheet valuation. 103 These are repeatedly requested by various parties in order to limit the scope of the balancers and to be able to make a claim of the life cycle assessment to generally accepted results. 104 It should be pointed out in advance that the term ecological balance, which has meanwhile become established, is misleading from a business point of view, since it is not an inventory calculation based on the key date, but rather an ecological profit and thus flow calculation. Cf. Grießhammer et al., S Cf. C.A.U. 1994, p. 2; Corino 1994, p. 3; Schmidt 1995, p. 6f 103 cf. SETAC 1993, p. 6f 104 cf. UBA 1992, p. 23 and 64; Grießhammer / Pfeifer 1993, pp. V and VII (summary) 105 See Schaltegger / Sturm 1992, p. 70; Möller / Rolf 1995, p. 52ff; Schaltegger / Kubat 1995, p. 5; Another author, however, accepts the term life cycle assessment: He defines the assets as the application side with beneficial functions of the object and, on the other hand, lists the eco-

26 19 The numerous existing definitions cannot be dealt with exhaustively here. 106 Even the Federal Environment Agency defines life cycle assessments somewhat inconsistently with a large number of terms, for example as the most comprehensive possible comparison of the environmental impacts of two or more different products, product groups, systems, processes or behaviors 107, but also as a complex assessment to be developed (only) for the product area - and evaluation procedures. 108 That it does not necessarily have to be a direct product comparison becomes clear again when the definition of the life cycle assessment cited by the Federal Environment Agency is also recognized for life cycle assessments: According to this definition, the comparison consists more in a comparison of existing conditions with a normative one to be introduced Dimension (actual, target comparison). 109 According to the Federal Environment Agency, the (German) term product line analysis only describes the environmental pollution associated with the life cycle of a product and also includes its benefit components as well as economic and social effects. The Öko-Institut Freiburg gives this big brother of the life cycle assessment greater opportunities to solve pending social issues. 110 The Federal Environment Agency therefore does not consider the extension of the analysis to include the aspects mentioned to be sensible, since benefit components can certainly already be taken into account in the standard LCA model. 111 Also the inclusion of social and economic aspects and logical burdens. He then cites a multifunctional product as an example, but in the following does not mention the obvious problem of difficult comparability of products that hardly match in all functions (cf. Mosthaf 1991, p. 191). 106 Schaltegger / Kubat 1995, p. 38ff. Offer an extensive collection of definitions of the term ecological balance. 107 UBA 1992, S ibid., P. 22; cf. also ibid. p. 16, where reference is also only made to the reference object product. But that an assignment to companies, processes, procedures, geographical areas and much more. m. is possible and common (cf. e.g. Corino 1994, p. 8; Schmidt 1995, p. 4; Braunschweig 1992, p. 5), is undisputed and is probably also meant in the formulation of the Federal Environment Agency (systems). 109 UBA 1992, S cf. Grießhammer / Pfeifer 1993, p. Vf (summary); see also Jasch 1992, p. 8, which also points to the necessity of including social requirements for a socially and environmentally compatible company. 111 One should think of usability criteria as a prerequisite for inclusion in the assessment. The Öko-Institut study is based on the performance test of the EU eco-label; In addition, assessments by Stiftung Warentest regarding washing performance were taken into account. (Cf. Grießhammer a.a., p. 56; Grießhammer a. A b, p. 134ff)