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Ecolabelling of printed matter - part II

2 Inventory

• 2.1 Composition of raw materials
  • 2.1.1 Film
  • 2.1.2 Film developer
  • 2.1.3 Fixer
  • 2.1.4 Biocides
  • 2.1.5 Plates
  • 2.1.6 Plate developer
  • 2.1.7 Gumming agent
  • 2.1.8 Paper
  • 2.1.9 Alcohol (IPA)
  • 2.1.10 Printing ink
  • 2.1.11 Fountain solution
  • 2.1.12 Lacquer
  • 2.1.13 Glue
  • 2.1.14 Cleaning agents
• 2.2 Consumption of raw materials
• 2.3 Emissions
• 2.4 Scenarios
  • 2.4.1 Scenario 1: Average energy
  • 2.4.2 Scenario 2: Saturated paper market
  • 2.4.3 Scenario 3: Variation in paper spillage
  • 2.4.4 Scenario 4: Variation in printing ink consumption
  • 2.4.5 Scenario 5: Waste water treatment included
  • 2.4.6 Scenario 6: Alternative biocide agent for rinsing water
  • 2.4.7 Scenario 7: No waste water emitted

The starting point for the inventory is the production stage of generic printed matter produced at a model sheet fed offset printing company. The raw materials included are described in the next section. Each raw material is divided into its components (see Section 2.1) and the resource consumption/emissions of the production of the raw material and its components (i.e. material stage) are mapped and included whenever readily available and relevant, see Figure 1. For many of the composite raw materials no data exists on production (i.e. typically a mixing process). However for their components generic data on resource consumption and emissions are available and used in many cases. In any case data on emission of specific substances at the material stage is typically not available and this kind of data is almost exclusively used in the production stage for which they have been available and focused upon in this study. Omissions that are assessed to be of possible significance are discussed later on in this report (e.g. Section 3.2. and Section 4.1.3). An overview of inventory references is given in Annex A and in Annex B data for the activities at the model printing company is shown together with data from 11 real world offset printing companies. A full aggregated inventory is shown in Annex C.

2.1 Composition of raw materials

The raw materials for the production stage included in this generic study are the dominant types typically used in ‘traditional’ sheet feed offset, i.e. film, film developer, fixer, biocides, plates, plate developer, gumming solution, paper, alcohol (isopropyl alcohol, IPA), printing ink, fountain solution, lacquer (varnishes), glue and cleaning agents. The composition of these raw materials is as far as possible based on known typically recipes as described in Larsen et al. (1995) in Danish and published in a short English version (Larsen et al. 1996). Other reports, articles and updated MSDS’s from suppliers/producers on relevant raw materials have also been consulted. However, due to lack of data (e.g. toxicity data) assumptions about the components have had to be made as shown below.

2.1.1 Film

The thickness of the film is assumed to be 0.1 mm (KODAK 2001a), the silver content 10 g/m² and the content of halides (assumed to be bromide) 7 g/m² (Baumann & Gräfen 1999a). The 0.1 mm thick base layer consists of polyethylene, PET (i.e. poly(ethylene terephthalate) (KODAK 2001a, Lapp et al. 2000). Other components such as gelatine and components with minor occurrence (i.e. well below 1% w/w) like filter dyes, fungicides and wetting agents, are excluded. As the density of PET is 1370 kg/m³ (APR, 2003) the generic film is assumed to consist of 89% w/w polyethylene, 6% w/w silver and 5% w/w bromine.

2.1.2 Film developer

The composition of the film developer is based on KODAK RA 2000 Developer (KODAK 2001b, 2003) and shown in Table 1. This developer is known to be used within the repro process at Danish sheet feed offset printing companies and its composition is in accordance with the general description of developers in Seedorff (1993).

Table 1. Composition of generic film developer. Working solution.

* For upstream production data substituted by ethylene glycol

2.1.3 Fixer

The composition of the fixer is based on KODAK 3000 Automix Fixer (KODAK, 2000, 2003) and shown in Table 2. This fixer is known to be used within the repro process at Danish sheet feed offset printing companies and its composition is in accordance with the general description of fixers in Seedorff (1993).

Table 2. Composition of generic fixer. Working solution.

2.1.4 Biocides

When rinsing water for film developing and plate making are recycled, biocides (algicides, fungicides, bactericides) are typically used (Kjærgaard 1997). One of the dominant types of biocides used within the printing industry is the group of isothiazolines, which in many cases is represented by Kathon® consisting of three parts 5-chloro-2-methyl-isothiazolin-3-one (CMI) and one part 2-methyl-2-isothiazolin-3-one (MI) (Larsen et al. 1995, 2002, Andersen et al. 1999, Gruvmark 2004). The product Nautalgin C1 (Deltagraph 1997) which is used as a biocide agent when recycling rinsing water contains about 1-2% CMI, 0.1-1% MI and water. The generic biocide agent used here for conservation of recycled rinsing water in film developing and plate making is therefore assumed to be water-based and containing 2% w/w CMI and 0.67% w/w MI. In Section 2.4.6 biocide agents used in the printing industry are further described.

Biocides occurring as part of raw materials (e.g. fountain solutions) are dealt with below.

2.1.5 Plates

The generic plate considered in this study is a mono-metal-positive-plate (aluminium), which is known to be used within sheet, fed offset plate making (Larsen et al. 1995). According to information from Hoechst (1994) on Ozasol® plates, the thickness of offset plates is in the range of 0.12 - 0.5 mm. Here we use the average 0.3 mm. As the density of aluminium is 2700 kg/m³ (IAI 2003) the mass of aluminium per square meter plate is 0.81 kg.

The emulsion layer on top of the plate has a thickness of 3 mm according to Baumann and Gräfen (1999b). The density of the emulsion is estimated to be 1230 kg/m³ on the basis of a weighted average (2:1) of the density (1200 kg/m³) of low molecular phenol formaldehyde resin (Muskopf 2000) and the density (1300 kg/m³) of polyvinyl alcohol (Baumann & Rothardt 1999). The mass of the emulsion per square meter therefore lies close to 4 g/m² (3.7 g/m²). According to Ludwiszewska (1992) the range is 1.5 g/m² - 4 g/m² plate, but for positive plates in most cases near the highest value.

So based on the figures estimated above, the generic offset plate is assumed to be composed of 99.5 % aluminium and 0.5% emulsion. The generic emulsion is assumed to have the composition shown in Table 3 (Larsen et al. 1995, KODAK 2002a).

Table 3. Composition of generic offset plate emulsion.

* For upstream production, data substituted by alkyd resin

** For example pigments

2.1.6 Plate developer

The composition of the generic developer is shown in Table 4 and based on Larsen et al. (1995).

Table 4. Composition of generic positive offset plate developer

2.1.7 Gumming agent

The composition of the generic gumming agent used in this study (see Table 5) is based on UNIFIN (Agfa 2002) which is known to be used within sheet fed offset and Larsen et al. (1995).

Table 5. Composition of generic gumming agent.

2.1.8 Paper

The generic paper used in the reference scenario in this study is a white uncoated fine type paper produced from sulphate pulp based on virgin fibres as defined in the Danish draft report on recycling of paper and card board (Frees et al. 2004). Another scenario considers the use of recycled paper at the model printing company Cycluspaper produced at the Danish paper mill Dalum Papir A/S and based on 100% recycled fibres (Frees et al. 2004). Even though coated paper like MultiArt Silk and Multiart Gloss from PAPYRYS has a widespread use within sheet fed offset printing, the coating process is excluded here. This is due to lack of readily available data, and the assessment that the coating process most probably is insignificant for the environmental impact as compared to the other processes included in the production of paper.

2.1.9 Alcohol (IPA)

The alcohol added to the fountain solution is typically 2-propanol (isopropyl alcohol, IPA) or a mixture of IPA (10%) and ethanol (90%) called IPA-spirit (Miljønet 2004). In this generic LCA, pure IPA is chosen.

2.1.10 Printing ink

Several different pigments, some different binders and solvents, and several types of additives are used in sheet feed offset printing ink. The generic composition shown in Table 6 has been chosen, mainly based on Larsen et al. (1995).

Table 6 Composition of generic sheet fed offset printing ink

Besides the composition of the ink, the upstream and down stream inventory substitutes are also shown in Table 6. “Upstream inventory substitute” means the chemical on which the inventory upstream from the production stage (not including the production stage) is based. ”Downstream inventory substitute” similarly means the chemical on which the inventory from production stage (included) and downstream is based. The reason for this division is that in many cases, upstream data are only available for certain substances or mixtures (e.g. modified phenol resin) within a functional group (e.g. binders) and furthermore, these data typically only include resource and energy consumption, and emissions given as “sum parameters” (e.g. COD, BOD) and not emissions of single substances. However, for the production stage we typically have a better knowledge of the composition of the raw materials, and individual substances can therefore be used when assessing emission from this stage and downstream if data on potential impact is available for these substances.

The pigments included in Table 6 (“typical” composition) are the most frequently used according to Larsen et al. (1995). The relative distribution within the group of pigments is based on an example from Baumann & Rothardt (1999) concerning a leaflet with 50 % area printed in four colour (half-tone; 20% black, 70% yellow, 50% blue, 50% red) and 20% area of text (15% black). The relative distribution of each pigment type is corrected for the different content of pigments in the different coloured printing inks according to Larsen et al. (1995).

The mix of pigments shown in Table 6 does not exist in any printing ink but should be seen as an attempt to reflect an approximation of the average relative consumption of pigments for producing generic printed matter by sheet fed offset. It may be relevant to look at a significantly higher relative consumption of carbon black (dominating in production of books) but this is not included in this study.

Pigment Yellow 12 (P.Y. 12), P.Y. 13 and P.Y 14 are all diaryl (diazo) pigments based on dichloro benzidine. The only difference in structure is the number of methyl groups, i.e. P.Y. 12 (no group), P.Y. 13 (four groups) and P.Y 14 (two groups) (Baumann & Rothardt, 1999). It seems unlikely that these differences would give rise to major significant differences in inventory data and environmental properties. Furthermore, P.Y. 14 (for which inventory data is available) is actually used in offset printing inks but to a much lesser extent than P.Y. 12 and P.Y 13 (Baumann & Rothardt, 1999).

Pigment Blue 15:3 (P.B. 15:3) is substituted by P.B. 15. Both of them are copper phthalocyanine pigments with only minor differences in structure, e.g. different crystal modification (Herbst & Hunger, 1993) and they share the same CAS number.

Pigment Red 57:1 (P.R. 57:1) belongs to the group of BONA (beta-oxynaphtoic acid) pigment lakes, which are monoazo pigments (Herbst & Hunger, 1993). This structure is quite different from the structure of the two substitutes (i.e. P.Y. 14 and P.B. 15) so this substitution is only justified by lack of data.

Carbon Black is not substituted.

Binders included comprise the dominant hard resin: Modified phenol resin, the alkyd resin: Soya oil alkyd, and the drying oil: Soya oil (actually semi-drying). No data is available on the modified phenol resin or the soya oil alkyd, and both of them are substituted by general alkyd resin.

The solvent n-paraffin (heavy) is substituted by one of its components tetradecane (Hansen & Gregersen 1986) for the inventory/impact assessment downstream.

Additives, e.g. siccatives and antioxidants, are excluded due to data lack and further commented in Section 3.2.

2.1.11 Fountain solution

The composition of the generic fountain solution concentrate is shown in Table 7. This composition is based on MSDS of two products from Akzo Nobel (2003a), Akzo Nobel (2004) and Larsen et al. (1995).  The full recipe for a fountain solution is very complex (Larsen et al. 1995), and only the known main components and very toxic components are included in Table 7. Other constituents like acids, surface active substances, corrosion inhibitors and more are excluded due to lack of data and these substances probably do not contribute significantly because they occur in very low quantities and/or are not very toxic, see Section 3.2 for further comments.

Table 7. Composition of generic fountain solution concentrate.

* For upstream production data substituted by ethylene glycol

** Part of Kathon

Fountain solution concentrates registered at the Danish Ecolabelling Agency all contain Kathon at the same concentration level, i.e. 0.0475%, 0.055% and 0.06%, and one type also contains 0.1% Bronopol (Gruvmark 2004).

2.1.12 Lacquer

Three main types of lacquer are used within finishing of sheet fed offset printed matter, i.e. water based lacquer, “offset lacquer” and UV lacquer. Consumption of water based lacquer (dispersion lacquer) is dominant, accounting for at least 80% (Brodin & Korostenski 1995, 1997) and water based lacquer is also used to a high degree as “anti-set-off-agent” in the printing process (Larsen et al. 1995). UV lacquer is excluded here due to lack of readily available data.

The composition of the generic water based lacquer is shown in Table 8 and based on Larsen et al. (1995, 2002), Andersen et al. (1999) Akzo Nobel (2003b) and Akzo Nobel (2004). Known potential components like anti foaming agents and softeners are excluded due to lack of data and further commented on in Section 3.2.

Table 8. Composition of generic water based lacquer.

* Here represented by undecyletherpolyoxy-ethylene (5)

According to Gruvmark (2004), water-based lacquers registered at the Danish Ecolabelling Agency either do not contain biocides or 0.016% – 0.025% chloracetamid or 0.005% – 0.007% bronopol.

The composition of the generic “offset lacquer” is shown in Table 9 and resembles a sheet fed offset printing ink without pigments.

Table 9. Composition of generic “offset lacquer”.

* Substituted by general alkyd resin for upstream production

** Substituted by tetradecane for downstream inventory

*** Excluded due to lack of data.

2.1.13 Glue

The only glue included here is Hot melt. It is very frequently used within the printing industry (Miljønet 2004) for finishing of catalogues, magazines and paperbacks (Brodin & Korostenski 1995, 1997; (Miljønet 2004) and in combination with dispersion glue for finishing of books. The generic composition of Hot melt is shown in Table 10 and based on the Hot melt product Superflex 225 (After Print 1983), Brodin & Korostenski (1995, 1997) and (Miljønet 2004). Antioxidants are excluded due to lack of data.

Table 10. Composition of generic Hot melt.

* Assumed to be the main component in EVA (Schmidt et al. 1993)

** A modified resin like phenol formaldehyde resin is, as in the case of the generic printing ink, substituted by alkyd resin here.

*** It is assumed here that wax can be represented by polyethylene wax which is often used in wax containing raw materials for the printing industry (Larsen et al. 1995).

2.1.14 Cleaning agents

Different types of cleaning agents are used in a sheet fed offset printing company. The main types include heavy aliphatic (paraffin based, low volatilization), light aliphatic (“ekstraktions benzin”, highly volatile), vegetable oil based, alcohol based, types based on surfactants, and different mixtures of these (Larsen et al. 1995, Akzo Nobel 2003c, Akzo Nobel 1998). Surfactants are both included in detergent-based types like shampoos and in pasta for cleaning rollers and as emulsifiers in some solvent-based types (Ludwiszewska 1992; Larsen et al. 1995). Destructors (ink removers) which are only used to a very limited degree (Larsen et al. 1995) are excluded here.

Table 11. Types of cleaning agents included in the study.

* It is assumed here that the surfactants only account for around 2% (Larsen et al. 1995) and that the rest is shared equally between the other types.

** Tetradecane is a component of aliphatic mixtures (C10 – C14) with distillation interval: 180 – 300°C (Danish: Petroleum).

*** Hexane is a component in aliphatic mixtures (C5 – C9) with a distillation interval of 60 – 140°C, i.e. “ekstraktions benzin” (Hansen & Gregersen 1986; Larsen et al. 1995) known to contain limited amounts (ca. 0.1%) of aromatics (Hansen & Gregersen 1986) here assumed to be benzene at its threshold value (0.1%) for classification when occurring in mixtures (ECC 1967 and its amendments, e.g. EC 2001).

The relative share of each of the cleaning agent types in Table 11 is assumed but supported by Larsen et al. (1995), Anonymous 1 (2000) and Anonymous 6 (2002). At one sheet fed printing company (Anonymous 1 2000) using widely used products, i.e. Synvex, Vegeol, Solvask and “ekstractions benzin” the exact distribution (%w/w) excluding surfactants is known, i.e. heavy aliphatic (21%), light aliphatic (23%), alcohol (29%) and vegetable oil based (27%). Based on these arguments the distribution in Table 11 is assessed to represent the average situation for sheet fed printing companies fairly well, at least in the Nordic countries.

2.2 Consumption of raw materials

The consumption of raw materials in the material stage and the disposal stage are taken into account to a degree defined by the unit processes included and generally not as detailed as the consumption at the production stage. For example, if we look at the paper production, raw materials included are mainly kaolin and wood but not, for example, adhesives and auxiliary materials (e.g. biocides), which are commented upon in Section 4.1.3.1.

The consumption of the raw materials and energy at the production stage is shown in Table 12.

Table 12. Consumption at the model sheet fed offset printing company; kg or m² per functional unit (fu). Values used in reference scenario in bold

* Based on inventory data from eleven offset printing industries: One sheet fed, one heatset and one cold-set-newspaper (Larsen et al. 1995), six sheets fed (Anonymous 1-6: Danish printing companies data from 1999, 2000 and 2002) and two cold-set-newspaper (Axelsson et al. 1997), see Annex B

** Estimated on basis of consumption of plate area and amount of emulsion per square meter (3.7g/m²) (Baumann & Gräfen 1999b)

*** Larsen et al. 1995

^# Kathon a.i.. Estimated on basis of content in rinsing water and rinsing water consumption.

^## Density of Goldstar Developer (Kodak 2002b) used.

^### Actual average of range is 0.87 but only 24.5% of total (0.245*2.5=0.61kg/fu) is allocated, see Table 11

^§ Spillage of paper for recycling 16% (4.5% - 32%)

^§§ Total lacquer consumption 5.6 (3.2 – 8)

^§§§ Spillage of paper for recycling 9.6% (3.3% - 19%)

The consumption figures used in the generic LCA are as far as possible based on data from the technical background document for the Swan criteria (Brodin and Korostenski 1995). However, in most cases data are missing and the investigation conducted in this project is used, see Table 12. For paper consumption, the average value calculated in this study is used instead of the average value in Brodin & Korostenski (1995) because the value from the technical background document seems far too low, at least in the Danish printing industry according to three anonymous Danish sheet fed offset printing companies (Anonymous 4-6 2003) and the Graphic Association Denmark (Bøg 2003). Large difference (a factor of 15) is also seen for ink consumption, which is dealt with in a sensitivity scenario.

The consumption of biocides for film developing and plate making is estimated on the basis of the average rinsing water consumption (se Table 12), and information on a typical dose of around 50 ml per 40 l rinsing water (Cederquist 2004) of a biocide agent i.e. Nautalgin C1 (Deltagraph, 1997) with a known biocide content (around 2.7% Kathon®). On this basis, the biocide active ingredient (a.i.) in the rinsing water can be estimated to 33 ppm.

2.3 Emissions

Emissions to air, water (and soil) from the material stage and the disposal stage are taken into account to a degree defined by the unit processes included and generally far from as detailed as the emissions at the production stage.

The emissions from the production stage included in this study are shown in Table 13.

Table 13. Emitted fractions of different materials and substances for the model sheet fed offset printing company (percentage of consumption). Figures used in bold.

* Excluded due to lack of data

** Assumed to be incinerated during recycling process of aluminium

*** Actually this is the paper spillage/waste at the printing company gathered with the purpose of recycling. However as for the paper that is part of the product it is assumed that 53% is recycled and 47% is incinerated according to the Danish situation in 2000 on general recycling of paper (Tønning 2002).

#Quantitative useful data on emission of Hot melt during use is not readily available. But based on the qualitative description in MiljøNet (2004) it probably primarily contributes to potential occupational health and safety problems in the workers’ environment which is not included in this LCA. However air emission of organic solvent components and other organic substances created during the heating process may contribute to LCA impact categories like photochemical ozone formation and human toxicity via air.

Emission of silver to water is estimated on basis of data from the technical background document (Brodin & Korostenski 1995) i.e. a relative coverage of ion exchange equipment of 22% leading to an average emission of 42 mg Ag/m² film.

Water emission of film developer is also estimated on basis of Brodin & Korostenski (1995), i.e. the typical value 0.02 l film developer/m² film. Density of developer is assumed to be 1.055 kg/m³ (KODAK 2001b).

Also for fixer, the water emission is calculated on basis of Brodin & Korostenski (1995) with a typical value of 0.08 l/m² and an assumed density of 1.31 kg/m³ (KODAK 2000).

As it is assumed that the rinsing water for film developing and plate making is preserved with biocide agent and after recycling is emitted as wastewater to the sewage system, the biocide agent emission to water becomes 100%.

For the offset plate, it is assumed that 100% of the aluminium is recycled, and for the plate emulsion 60% ends up in the developer of which 40% ends up in the rinsing water (Larsen et al. 1995). As it is assumed that the rinsing water after recycling is emitted to the sewage system, 24% of the emulsion is emitted to water. The remaining 36% is disposed of as chemical waste together with the used developer.

Gumming solution typically ends up in either rinsing water during the plate making process (Anonymous 5 2003) or in the fountain solution during printing (Larsen et al. 1995). As both rinsing water and fountain solution are assumed to be emitted to the sewage system 100% of the gumming solution is emitted to water.

For paper, the spillage/waste amount for recycling is set to 16%. The rest follows the product (see Table 12 and Table 13). It is assumed that 53% of the paper consumption (including both spillage and product) is recycled and the rest i.e. 47% is incinerated and the heat utilised. This assumption is based on the Danish situation in 2000 (Tønning 2002).

Printing ink emitted to water (e.g. via fountain solution) is assumed to be 1% of ink consumption (Larsen et al. 1995). The percentage ink disposed as chemical waste is estimated to 20% (range: 2.4% – 45.9%) on the basis of data from Larsen et al. (1995), Anonymous 1- 2 (2000), Anonymous 3 (2002) and Anonymous 5 (2003).

86% of the IPA consumption is assumed to be emitted to air, either as a separate chemical or as part of the fountain solution agent (Larsen et al. 1995). The rest (14%) is assumed to be emitted to the sewage system as part of the used fountain solution. All other components of the fountain solution (biocides and diethylene glycol) are assumed to be fully (100%) emitted to water.

For cleaning agents (see Table 13), the emissions to air and water are mainly based on Larsen et al. (1995), and the rest is assumed to be disposed of as chemical waste. As a minor part of the cleaning is done on dampening form rollers with cloth, 50% of the surfactants are assumed to be emitted to water. The rest is assumed to be part of cleaning agents (e.g. as emulsifiers in solvent based types) for which emission to water is very limited (0.1 – 1%) (Larsen et al. 1995). However, as low/none volatile solvents may be part of detergent based types for cleaning dampening form rollers with cloth, emission to water of vegetable oil and low volatile aliphatics is set to 1% whereas emission to water of the highly volatile “ekstraktions benzin” is set to 0.1%. Emission of alcohol to water is set to 1% because of high water solubility. The part of the cleaning agent not emitted to air or water is assumed to be disposed of as chemical waste.

On the basis of data from Anonymous 4 (2003), the part of water-based lacquer emitted to water is set to 5% of consumption (due to both cleaning and disposal of lacquer waste). The rest is assumed to be part of the product. For the offset lacquer (oil based) the emission to water is assumed to be only 0.1% of consumption due to a lower number of cleaning cycles (no colour change) and handling of waste as chemical waste (Larsen et al 1995).

2.4 Scenarios

The inventory data described above are used in the reference scenario. A number of alternative scenarios based on the reference scenario but with changes in some of the parameters, are described below.

2.4.1 Scenario 1: Average energy

As described earlier, the reference scenario is based on a marginal electricity approach where electricity production is based 100% on natural gas. However, in a previous LCA study also on offset printed matter (Drivsholm et al. 1996, Drivsholm et al. 1997) an average electricity approach is used, e.g. average Swedish electricity production in 1990 is used for electricity consumption related to the paper production. In the Swedish electricity scenario, nuclear energy production is dominant (67.8%) together with water power (26.5%). In order to be able to compare the LCA profile from this study with the profile from the former study, a Swedish energy scenario is also used in scenario 1 in this study. In addition, a Danish average electricity scenario based on data from 1997 is used in scenario 1 for the electricity consumption at the model printing company. References for the different energy approaches are compiled in Annex A.

2.4.2 Scenario 2: Saturated paper market

The reference scenario is, as described earlier, based on an unsaturated market for recycled paper. However, a comparison between generic offset printed matter based on recycled paper and a virgin paper based type will give no difference if the “unsaturated paper market” approach is used. In scenario 2 the market for recycled paper is assumed to be saturated, leading to a situation where additional use of paper leads to use of more recycled paper rather than production of virgin paper. In this scenario, the printed matter production based on recycled paper will draw the in and output for recycled paper production and thus, for example, benefit from the lower energy consumption for producing the recycled paper (as compared to virgin paper). The references for the paper recycling unit process are shown in Annex A.

2.4.3 Scenario 3: Variation in paper spillage

In order to investigate the effect of differences in paper consumption (e.g. due to variation in percent spillage/waste) on the LCA profile, scenarios with 3.3% paper waste and 32% paper waste respectively are carried out and compared. All other parameters are the same as for the reference scenario and the two tested paper consumptions are taken from the observed extremes, see Table 12. Even though a higher spillage of paper may lead to a higher consumption of ink this is not included here because we want to look at the paper separately and we do not know the size of the extra ink consumption. Variation in ink consumption is dealt with below.

2.4.4 Scenario 4: Variation in printing ink consumption

To investigate how much changes in consumption of ink (e.g. due to reduction in printing ink spillage/ink waste) alter the LCA profile, a scenario with 1.8 kg ink/fu is compared with a scenario with 26.5 kg ink/fu. All other parameters are the same as for the reference scenario and the two tested ink consumptions are taken from the observed extremes, see Table 12.

2.4.5 Scenario 5: Waste water treatment included

The reference scenario does not take treatment of the wastewater in wastewater treatment plants (WWTP) into account. Especially in Denmark and Sweden, but also to a high degree in northern Europe, wastewater is treated in WWTP (including a biological step, i.e. biodegradation) before emission to the water recipient. But in southern Europe, and especially in Eastern Europe, treatment in WWTP is not that widespread. An indication of the differences can be found in the TGD (EC 2002) showing that the proportion of the population served by WWTP in Denmark and Sweden in 1995 was 99% and 95% respectively whereas the figures for Greece and Portugal show 34% and 21% respectively.

The substances emitted to waste water during the production stage, which may contribute significantly to the impact categories including ecotoxicity are the biocides (benzalkonium chloride, Kathon and Bronopol), tetradecane, pigments (P.Y. 12, P.R. 57:1 and P.B. 15) and surfactants (sodium-dodecyl-diphenyloxide-disulphonate, undecyletherpolyoxyethylene (5)). Benzalkonium chloride is only used in scenario 6 (see section 2.4.6). The fate of these substances in a WWTP with a biological step (for biodegradation) is shown in Table 14

Table 14. Fate in a WWTP of different substances used in the printing production process

* Based on general data for quaternary ammonium compounds

** Estimated on basis of Appendix II in the TGD Part II (SimpleTreat 3.0) (EC 2002)

*** Based on general data for linear alkyl benzene sulphonates (LAS)

**** Based on general data for alcohol ethoxylates (AEO)

2.4.6 Scenario 6: Alternative biocide agent for rinsing water

As shown in Table 15, different biocides at different concentrations are used for preserving rinsing water. The highest recommended dose is for one of the benzalkonium chloride containing agents. Benzalkoniun chloride is at the same level of toxicity to aquatic living organisms as the components of Kathon and furthermore considered as non-inherently biodegradable.

Table 15. Biocide agents used for preservation of rinsing water in the printing industry in Scandinavia. Based on Gruvmark (2004) if not otherwise stated.

* Used in the reference scenario and based on Deltagraph (1997) and Cederquist (2004)

^# (Exact value)

To investigate how much the use of a biocide agent, registered at the Danish Ecolabelling Agency for preserving rinsing water (repro, plate making), may change the LCA profile of the reference scenario, rinsing water with 5000-ppm benzalkonium chloride is used in this scenario. To reflect to typical situation in Northern Europe, the fate in WWTP is included, i.e. only 10% of the benzalkonium emitted to the sewage system ends up in the water recipient after treatment in the WWTP (see Table 14)

2.4.7 Scenario 7: No waste water emitted

At least some Danish sheet fed printing companies emit no wastewater at all. Recycled rinsing water from the film developing may be used when replenishing the fixer and other wastewater may be collected and disposed of as chemical waste. In order to reflect this kind of situation, we use a scenario based on the reference scenario but with all water emissions at the production stage excluded. However LCA data on treatment of chemical waste is not readily available and it has not been possible within the scope of this study to include a separate study on the potential environmental impact of disposing of used rinsing water as chemical waste.

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