Paradigm for Substance Flow Analyses

Appendix 5

Summaries of Selected Danish Substance Flow Analyses

English summaries of selected Danish substance flow analyses are presented in the following appendix. The summaries are identical to the summaries in the reports, but minor layout changes have been carried out.

Substance Flow Analysis for Copper

Substance Flow Analysis for Phthalates

Substance Flow Analysis for Nickel

Substance Flow Analysis for Lead

Substance Flow Analysis for Mercury

Substance Flow Analysis for Tin - with Focus on Organotin

Aluminium - Substance Flow Analysis and Loss Reduction Feasibility Study

Substance Flow Analysis for Dichloromethane, Trichloroethylene and Tetrachlorethylene

Brominated Flame Retardants - Substance Flow Analysis and Assessment of Alternatives

Substance Flow Analysis for Copper

Carsten Lassen, Thomas Drivsholm, Erik Hansen, Benthe Rasmussen & Kim Christiansen. 1996. Environmental Project no. 323.

The Danish EPA, Copenhagen

English Summary

This report presents a relatively detailed analysis of copper consumption and emission to the environment in Denmark. The report is prepared ac-cording to the Danish Environmental Protection Agency's paradigm for substance flow analysis /1/.

The present knowledge is acquired through information from the Danish National Agency of Statistics, the Product Database of the Danish En-viron-mental Protection Agency, technical literature, private companies and governmental institutions.

Copper balance for the Danish society is summarized in figure 2.2.

Figure 2.2
Copper balance for the Danish society (tonnes Cu/year)

The net supply of copper to the Danish society with raw materials, semi-manufactured and finished goods, inclusive unintended use of copper as contaminant in other products, amounted to 26,000-33,000 tonnes Cu/year (Fig-ure 2.2). The net import of copper with raw materials and semi-manufactured goods made up 28,000-29,000 of this. About 25% of the raw materials were recycled as chips and stumps from the manufacturing of goods. Scrap containing about 10,000 tonnes copper was in 1992 in Denmark melted down to refined copper (mainly brass bars).

The copper balance in figure 2.2 only gives a simplified illustration of the total circulation of copper in Denmark as an exact determination of import and export of copper with manufactured goods has not been possible. In the analysis information on the total copper content of produced and consumed industrial products was retrieved from the Product Database of the Danish Environmental Protection Agency. From these data only the net import of copper with industrial products could be determined. In broad outline the total copper content of produced products balanced the total content of consumed products. Considering the uncertainty on the estimates, the net export with industrial products is estimated to (-2,000)-4000 tonnes Cu/year. With valves and fittings there was a considerable net export, whereas there was a net import of copper with wires, electronics, lighting devices, and domestic electric appliances.

The consumption differentiated on uses is presented in table 2.3 (summarised from table 5.2)

Table 2.3
Copper consumption with manufactured goods in Denmark 1992 1)

Electric conductors and equipment for the main system of transmission lines (switchboards, transformers, etc.), constituted about 26% of the total copper consumption (electric conductors in electronic and machines are not included). Other key fields of application were valves, fittings and copper castings (17%), building materials (13%), means of transport (12%) and electric machines (11%). Electronics (computers, audio visual apparatus etc.) only constituted about 5% of the total consumption.

The nutritive effect of copper on plants was utilized by addition of copper compounds to fertilizers (1.4%), whereas the toxicity of copper to microorganisms, algae and fungi was utilized in pressure impregnation chemicals (0.6%), anti fouling paints (0.1), fungicides, and agents to prevent damage caused by game. Copper in pigments and dyes was used for a wide range of paints and inks (0.4%).

Copper as contaminant

A considerable amount of copper was circulated as alloy (most frequently unintended) in steel (4%). Copper as natural contaminant in other products amounted to about 0.5% of the total copper consumption.

Emission to the environment

Emission of copper to the environment and solid waste disposal are represented in table 2.4 (summarized from table 5.3).

Air Foundry processes and energy production were the principal sources of copper emission to air, but it is emphasized that emissions to air were relatively small compared to the intentional spread of copper to soil and aquatic environments.

Water The principal source of copper to the aquatic environment was antifouling paint on ships (about 38%). Discharge from municipal sewage plants and loss of copper slag from sand blasting comprised about 33% and 6%, respectively, of the total emission to the aquatic environment. It is emphasized that these contributions are estimated with considerable uncertainty. Corrosion of copper roofs, sheets, wires and pipes are considered to be key sources of copper to municipal waste water. However, nothing definite is known about total emissions from these sources.

Soil Copper predominantly was released to soil with fertilizers (about 80%). Manure was the principal source as copper added to feeding stuff was transferred to the manure. Municipal sewage sludge comprised 5% of the release, and fungicides inter alia pressure impregnation chemicals comprised another about 5%.

Based on analysis of disposal of consumer products it is estimated that 3,000-5,800 tonnes copper in 1992 was disposed of with municipal solid waste (MSW). The sources of copper to MSW were wires and power cords used in the home, electronics, domestic appliances, lighting devices, furnishings, locks, keys, clothing, leather goods and a number of other products. Copper as natural contaminant in products (e.g. wood, paper, and plastic) which can be considered as the MSW background level only comprised 1% of the total disposal.

Disposal of solid waste The bulk of the MSW was incinerated and copper was disposed of with residues. The available analysis for copper content in these residues indicate that the MSW contains less copper. The object of these analysis, however, has been to evaluate the potential leaching from the residues and metal pieces were sorted out before analysis, and consequently the total copper content was presumably underestimated.

Table 2.4
Emission of copper to the environment and solid waste disposal in 1992.

Link to table 2.4

Iron and steel

About 430-850 tonnes copper, mainly in small parts, ended up in scrap iron, which was melted down to new steel containing the copper as alloy (contaminant). About 97% of discarded iron and steel is recycled and consequently - despite the addition of virgin iron to the melt - the steel contains still more copper for each remelting. In total 1,000-1,800 tonnes copper was circulated with steel in 1992.

Recycling

There is a comprehensive trade with scrap copper. Wastes from the production of industrial products are nearly 100% recycled. It is estimated that 23,000-32,000 tonnes copper in 1992 was recycled. Taking account of that 4,800-9,000 tonnes Cu was deposited, lost or ended up as unintended alloy in steel, the recycling percentage (the percentage of discarded copper which was recycled) was roughly estimated 80%.

Stock building

The stock building in the Danish society in 1992 is estimated to 5,000-16,000 tonnes copper. The standing stock in the Danish society are presumably in the order of 200,000-1,000,000 tonnes copper.

Trends

A detailed analysis of trends in consumption for all uses of copper has not been possible within this scope of this study. The consumption of copper wire has declined to about 30% of the consumption in the early seventies presumably owing to substitution of copper with aluminum for electric conductors and substitution of copper wires with fibre-optic cables for telecommunication. For most other uses of metallic copper the consumption has increased.

The consumption of copper with pressure impregnation chemicals is expected to decrease in the next few years and the consumption of copper with fertilizers has a downtrend too. On the other hand the supply of copper with chemical compounds seems to be increasing and it has not been possible to give a satisfactory explanation of this increase.

Conclusion

In short, the conclusion is that unintended emissions to the environment are small compared to the intended spread of copper. The production of copper-containing industrial products caused only minor emissions to the environment.

The recycling percentage of copper was considerably lower than the recycling percentage of iron in spite of relatively high prices on scrap copper. The explanation is that copper in small amounts form part of a wide range of composite products, from which it today is not profitable to recover the copper.

About 20% of the used copper is lost to the environment or deposits and the quantities of copper deposited (including clinkers used for construction works) seems to be higher than formerly supposed in Denmark.

Substance Flow Analysis for Phthalates

Leif Hoffmann. 1996. Environmental Project no. 320.

The Danish EPA, Copenhagen

English Summary

A detailed analysis of phthalates, their use in production, as a final product and their emission into the environment in Denmark in 1992 has been carried out. The analysis is based on information obtained from Statistics Denmark, the National Institute of Occupational Health (Product Register), public institutions, private companies and literature.

A simplified phthalate balance is shown in figure 2.1. The balance is described in detail in chapter 6.3

Figure 2.2
Phthalate balance for Denmark 1992.

Use

The import of phthalates in Denmark is estimated at 11,500-14,000 ton/year. The estimate is based on import of phthalates, compounded PVC and semi-manufactured articles. Imports consist of 6,500 ton phthalates, 3-5,000 ton phthalates with compounded PVC, 2-2,500 ton phthalate with semi-manufactured products. The import of lacquer, paint, printing ink, adhesives, fillers, denaturation substances and semi-manufactured products/-products in other areas of application has not been investigated in detail, since the use of these products is primarily covered by production in Denmark.

The use of phthalates is divided into areas of application as shown in table 2.1.

Table 2.3
Survey of estimated consumption of phthalates in Denmark in 1992 in different areas of application.

Emission to the environment

The total emission of phthalates to the environment in 1992 may be estimated at:

	1.4-20 ton phthalates/year to air
	13-18 ton phthalates/year to water from wastewater treatment plants
	5-8 ton phthalates/year to soil with compost and sludge from wastewater treatment
	1,600-4,400 ton phthalates/year to waste disposal

A simplified survey of disposal and emission of phthalates to the environment in 1992 is shown in table 2.2; a more detailed survey is presented in chapter 6.2, table 6.3.

Air

Emission of phthalates to air primarily occurs during the manufacturing process of PVC since this is carried out at 130-210 °C leading to a potential risk of evaporation of phthalates. The highest emission comes from manufacturing of plastisols, i.e. coating of textiles, rotational and injection moulding. Other production processes are primarily carried out at room temperature and, therefore, do not normally result in significant emissions to air. Emission from products containing phthalates is less investigated. Literature on the subject shows that most tests are carried out as accelerated tests and, therefore, estimation of emission factors is difficult.

Emission to air is estimated at 1.4-20 ton phthalates/year. The most important sources are estimated to be:

	extrusion of cables: 0.5 ton phthalates/year
	calandering of foils: 0.2-4 ton phthalates/year
	extrusion of tubes and profiles: 0.3-0.5 ton phthalates/year
	production of other products: < 7 ton phthalates/year
	use of cables : 0.3-3 ton phthalates/year
	use of other products of PVC: 0-2 ton phthalates/year
	use of cosmetic products: < 2 ton phthalates/year

The estimates of air emissions are based on estimated emission factors and the uncertainty of the estimates is expressed in the width of the intervals. The estimate of the emission from use of cables is considered to be the most uncertain estimate. Air emissions during the user phase and waste disposal are considered negligible compared to emissions from production of PVC.

Water

Emission of phthalates to (waste)water is primarily caused by the use of plastiziced products, e.g. flexible PVC, lacquer, paint and printing ink and also adhesives. Only production of adhesives contributes significantly to the emission as products containing phthalates are manufactured in processes not often involving water (except use of cooling water or production of waterbased adhesives). Therefore, the possibility of emission of phthalates to the aquatic environment from manufacturing is considered minimal. Emissions to the wastewater system are estimated at 5-80 ton phthalates/year. The most important sources are considered to be:

	cleaning of machines and other (adhesives): 1-40 ton phthalates/year
	washing of printed textiles (PVC print): 1.3-13 ton phthalates/year
	wall and floor sheets: 0.1-11 ton phthalates/year
	use of "other products": 0-4 ton phthalates/year
	use of tubes and profiles: 0.03-0.45 ton phthalates/year
	lacquered floors, etc.: 0.02-0.8 ton phthalates/year
	production of adhesives: 0.2-2.2 ton phthalates/year
	production of flexible PVC products: < 1 ton phthalates/year

There is also an unknown contribution from atmospheric deposition.

The estimates are based on estimated emission factors and the uncertainty of the estimates is expressed in the width of the intervals. The estimate of the emission from use of adhesives is considered to be the most uncertain estimate. Emissions to water during production processes are considered to be negligible compared to emissions from use of different products containing phthalates.

It should be stressed that documentation for some of the estimated emissions are missing, e.g. emission of phthalates during production and use of water-based adhesives. Therefore, it is recommended that such emissions should be subject to close investigation through specific measurements.

Table 2.4
Disposal and emission of phthalates to the environment in Denmark in 1992.

Link to Table 2.4

Wastewater treatment

The amount of phthalates in the inlet to wastewater treatment plants has been estimated at 115 ± 82 ton phthalates/year as the sum of 31 ± 34 ton DBP/year, 52 ± 74 ton BBP/year and 32 ± 4 ton DEHP/year. The amount of other phthalates and one single adipate (DEHA) was equal to or below the detection limit. The estimated emission of phthalates from production and use of products containing phthalates is seen to explain the lower part of the level found in inlet to wastewater treatment plants.

Only DEHP could be detected in significant amounts in sludge and outlet water from wastewater treatment plants. The levels were 7 ton DEHP/year in sludge and 13 ton DEHP in outlet water. The total amount of phthalates in outlet water is estimated at 13-18 ton/year. The total amount of phthalates in sludge is estimated at 7-12 ton/year and 5-8 ton/year is spread on agricultural soil, 1-1.5 ton/year is deposited and 1.5-2.5 ton/year is incinerated.

The reduction in wastewater treatment plants has been measured for DBP, BBP and DEHP, and the reduction of DBP and BBP is approximately 100 % while the reduction of DEHP is 25-75 %. 20-45 % of DEHP in inlet is found in sludge.

Recycling

Recycling of phthalates as a product does not take place. Recycling is not considered technically possible. Through recycling of flexible PVC, phthalates are indirectly recycled.

Substance Flow Analysis for Nickel

Carsten Lassen, Thomas Drivsholm, Erik Hansen, Benthe Rasmussen & Kim Christiansen. 1996. Environmental Project no. 318.

The Danish EPA, Copenhagen

English Summary

This report presents a relatively detailed analysis of nickel consumption and emission to the environment in Denmark. The report is prepared according to the Danish Environmental Protection Agency's paradigm for substance flow analysis /1/.

The present knowledge is acquired through information from the Danish National Agency of Statistics, the Product Database of the Danish Environmental Protection Agency, technical literature, private companies and governmental institutions.

Nickel balance for the Danish society is summarized in figure 2.2.

Figure 2.2
Nickel balance for Denmark 1992/93 (tonnes Ni/year)

The supply to the Danish society in 1992 with raw materials, semi-manufactured and finished goods, inclusive nickel as natural contaminant in other products, amounted to 6,400-8,500 tonnes nickel (Figure 2.2). A part of this - roughly estimated 1,000 tonnes nickel - was reexported as production residues and, consequently, the nickel consumption within the society can be estimated to 5,400-7,800 tonnes.

The consumption differentiated on uses is presented in table 2.3 (from table 5.1).

Stainless steel products comprised 80% of the total nickel consumption. The principal application of stainless steel was as pipes and containers which alone made out 40% of the total nickel consumption.

Table 2.3
Consumption of nickel with manufactured goods in Denmark 1992/93.

Emissions to the environment and release to waste deposits are summarized in table 2.4 (from table 5.3).

Emission to air

The emission to the air was mainly caused by burning of oil products - particularly fuel oil - which contributed to the total emissions by 90%. Solid waste incineration comprised about 5% of the total emission to air.

Emission to water

Wastewater/stormwater was the principal source of nickel emission to the aquatic environment. The principal sources of nickel in municipal waste-water were wear of nickel platings, natural content of nickel in ground water, and road dust containing nickel from bitumen in the asphalt. Nickel plating was the only industrial process which contributed significantly to the total emission to wastewater. Road dust and atmospheric deposition were probably the primary sources of nickel in storm water. It has not been possible to quantify the release of nickel by cleaning of stainless steel products (e.g. pipes and tanks) which might be significant.

Release to soil

The release of nickel to soil was primarily due to the use of phosphate fertilizers, feeding stuff and agricultural lime. The agricultural soils were supplied with 38-111 tonnes Ni/year by these sources of which feedstuff was the principal. The nickel content of feed is regulated by mid 1995.

Disposal of solid waste

The present estimated discards of nickel in solid waste significantly exceeds former estimates based on analysis of solid residues from solid waste incinerator plants. The principal source of nickel in solid waste was products containing stainless steel and other nickel alloys. Nickel in these alloys are not included in the former presented analyses of residues from incinerator plants as metal pieces have been sorted out before the chemical analysis.

Table 2.4
Emission of nickel to the environment and solid waste disposal in 1992/93.

Link to Table 2.4

The principal part of nickel disposed of in solid waste derives from household uses (e.g. cutlery, keys and nickel-cadmium batteries) or from industrial products (e.g. tires) where the nickel-containing part only comprise a minor part of the product.

From March 1995 regulations are laid down for recycling of tires from automobiles.

The dominant part of the nickel consumption in the society is related to stainless steel used for production equipment, which after its useful life will be dismantled and exported through scrap merchants for reprocessing.

The consumption of nickel significantly exceeded the disposal (incl. scrap export) indicating that a substantial part of the consumed nickel accumulates in the society in production equipment and households.

Substance Flow Analysis for Lead

Carsten Lassen & Erik Hansen. 1996. Environmental Project no. 327.

The Danish EPA, Copenhagen

English Summary

This report presents a relatively detailed analysis of lead consumption and emissions to the environment in Denmark in 1994. The report is prepared according to the Danish Environmental Protection Agency's paradigm for substance flow analysis.

The present knowledge is acquired through information from the Danish National Agency of Statistics, technical literature, private companies and governmental institutions.

Lead balance for the Danish society is summarised in figure 2.2.

Figure 2.2
Lead balance for Denmark; 1994 (tonnes Pb/year)

The total lead consumption with manufactured goods in Denmark in 1994 is estimated at 15,500-19,800 tonnes/year. The turnover of lead in the society was somewhat higher as there aside from this was an import of lead with raw materials which were manufactured and reexported with manufactured goods. The total import in 1994 is estimated at 19,900-22,000 tonnes lead.

The export covered batteries, keels, cables, and factory-mounted flashing on roof lights and chimneys.

Additionally 430-770 tonnes lead was recycled and used in Denmark for casting of lead sheets for roofs, sinkers and lead lines for fishing, seals, counterweights, and home-cast fishing tackle.

Lead consumption

Lead consumption, differentiated on uses, is shown in table 2.3 (summarised from table 5.1).

Batteries accounted for about 48% of the total consumption. Other significant fields of application was lead roofs and flashing (about 20% ) and cable sheaths mainly on deep sea cables (about 12%). About 2.5% of the total consumption was used for the fishing trade while tackle for angling (mainly jigs and sinkers) made up about 0.5 % of total consumption.

Table 2.3
Consumption of lead with manufactured goods in Denmark; 1994 2)

Other uses as metal cover solder for radiators, electronics and light bulbs, vehicle wheel weights, miniatures (e.g. tin soldiers), cones for flower decorations, radiation shields, sheets for corrosion protection of industrial equipment, seals for gauges, counterweights, curtain weights, weights for vibration and sound damping, and a number of other minor uses.

Chemical compounds

The consumption of lead with chemical compounds in 1994 is estimated at 1,000-1,700 tonnes or about 8% of the total consumption. About half of this was lead in crystal glass (Pb3O4) and cathode ray tubes (PbO) in television sets and computer monitors (about 5%). Lead silicate was used for glazing on ceramics (about 0.7% of total consumption). Lead stabilisers in PVC represented about 2% of the total consumption while lead pigments in paints and plastic represented 0.4%. Other uses as chemical cover red lead for corrosion protection (0.2%), petrol additives, drying agents in paint, brake lining, and lubricants.

Lead as natural contaminant

Unintended uses of lead as natural contaminant comprises trace amounts of lead in coal and oil, wood, fertilisers, agricultural lime, cement, feeding stuff etc. which totals 70-190 tonnes (1% of the total lead consumption).

Emissions to the environment

Emissions to the environment and release to waste deposits are shown in table 2.2 (summarised from table 5.3).

Emission to the air

The total emission of lead to the air is estimated at 11-33tonnes lead per year.

Emissions to the air was mainly due to burning of leaded petrol (about 33% of total emission) and solid waste incineration (about 20% of total emission). The emission from burning of petrol is expected to further decrease in 1995, where leaded petrol only is used in some types of aviation petrol. Beyond this lead was emitted in significant amounts from energy production (about 17% of total emission), production of steel (about 10% of total) lead casting (about 16% of total), and production of ceramics and tile (5% of total). The emissions from lead casting is determined with high uncertainty and was mainly due to casting in the open air without improved flue gas cleaning.

Discharge to aquatic environments

The total discharge to aquatic environments is estimated at 50-300 tonnes lead per year. The main source was loss of sinkers used by anglers and the fishing trade which is estimated to contribute at about 51% of total discharge. Angling is estimated to contribute to the same extent as the fishing trade to the discharge. Cables left at the sea floor made up about 47% of the total discharge. The quantity does not represent the release of lead from the cables to the sea water, but the total quantity left on the sea floor (estimated annual mean).

Storm water drained directly to recipients represented the main part of lead discharge with waste water/storm water (about 1% of total discharge), whereas more than 90% of the lead entering sewage disposal plants was retained with the sludge. The predominant source of lead to municipal waste water is estimated to be lead oxides corroded from lead flashing and roofs.

Release to soil

The most significant source of lead release to soil was sheaths on cables left in the ground. Since 1945 about 150,000-200,000 tonnes of lead have been used for underground cables in Denmark. When the cables are taken out of service they are either dug up or left to slowly disappear by corrosion. There is no registration of the total quantity left and the quantity given in table 3.4 is estimated with high uncertainty (estimated annual mean).

Recycling

About 420-570 tonnes lead was in 1994 exported with ashes and dust from steel production and foundries. In total 10,400-12,700 tons lead with scrap and wastes was recycled in Denmark or exported including scrapped lead batteries (7,900-8,600 tonnes lead), sheets used for flashing (600-1,200 tonnes lead), and cables sheaths (550-800 tonnes lead). Recycling of lead within the Danish society is estimated at 430-770 tonnes

The scrap was predominantly exported for recasting abroad. However, a significant part of the cables were reprocessed in Denmark as there was an import of cables for reprocessing. The product of the reprocessing was mainly exported.

Table 2.2
Emission of lead to the environment and solid waste disposal; 1994

Link to Table 2.2

Depositing

About 1,800-3,600 tonnes lead was deposited (including construction work etc.). The main sources were residues from solid waste (800-1,200 tonnes lead), shredder waste (200-1,000 tonnes lead), electronics including cathode ray tubes (350-580 tonnes lead), and fishing equipment (230-300 tonnes lead).

Stock building

On the present basis it is estimated that (-3,500)-6,200 tonnes lead annually is accumulated in the society (a negative accumulation means that the stock in the society is decreasing). The stock comprises lead in cables (100,000 -200,000 tonnes lead), roofs and flashing (80,000-120,000 tonnes lead corresponding to 30 years consumption), and batteries (30,000-40,000 tonnes corresponding to four years consumption). Additionally 10,000-50,000 tons is accumulated in keels, X-ray laboratories, electronics, PVC, glass and other products. In total, the accumulation is estimated at 220,000-410,000 tonnes lead.

Trends in consumption

Trends in consumption in the recent ten years appears from a comparison of the present analysis with a previous substance flow analysis from 1985 (Table 5.2 and 5.4).

The consumption of lead shot was, due to legislative restraints on the use, reduced from 870 tonnes lead in 1985 to about 130 tonnes in 1994. Lead consumption with petrol additives has likewise decreased from 250 tonnes lead in 1985 to less than 10 tonnes in 1994 due to substitution of lead additives.

The consumption of lead with keels has decreased due to declining sales of new sailingboats.

The consumption of lead batteries seems to have declined, but a part of the apparent decline may be due to an overestimation of the consumption in 1985.

The consumption of lead with cables and construction works, which next to batteries represent the principal fields of application, has in broad outline been stagnant during the last ten years.

Within some minor fields of application the consumption has decreased considerably. Consumption of lead with seals for gauges, wine bottle seals, tubes and fittings, corrosion protection in chemical industry, and soldering of tins is considerably reduced or ceased.

Mainly due to working environment problems, the use of lead with drying agents for paints and lead pigments in glazing, paints and yellow road lines has decreased and seems gradually to cease. Red lead is today only used for repair work on old iron constructions and fishing boats.

Lead consumption with glass has increased due to an increase in consumption of cathode ray tubes in television sets and computers which comprise the main part of the consumption of lead glass. In crystal glass produced in Denmark, lead is substituted with other metal oxides, but this seems not to be the case for most of the imported crystal glass.

The consumption of lead stabilisers in PVC is increasing too.

Red lead and pigments used for ceramics and tile is nearly phased out whereas the consumption of lead silicates for ceramics is stagnant.

Trends in emission and disposal

While the total consumption of lead in the recent ten years has been nearly stagnant, emissions to the environment has declined considerably due to legislative restraints and improved cleaning technology.

Emission to the air has been reduced from 250-300 tonnes lead in 1985 to - tonnes in 1994. The reduction is due to substitution of lead additives to petrol and reduced emissions from solid waste incineration, power plants, battery production, and burning of waste oil.

Discharge to aquatic environments was reduced mainly as a result of the ban on use of lead shot in wetlands and improved treatment of waste water. Additionally, the contribution from red lead released by repair work is estimated to be lower than in 1985.

Both in 1985 and 1994, release of lead from cable sheaths is estimated to be a considerable source of lead contamination of soil and aquatic environment although the released quantity is estimated with a high degree of uncertainty. Generally deep sea cables are left at the sea floor when the cable is taken out of service. As regards underground cables it seems to be common to dig up old cables if a new cable is placed in the same track. If not, the old cable seems generally to be left in the ground. Today lead sheaths are mainly used for deep sea cables.

An important part of the release of lead to soil in 1985 was caused by loss at scrap dealers. This release has decreased considerably mainly due to a better handling of batteries. Scrap batteries are today statutory stored and exported in closed acid resistant containers. Additionally many scrap yards has been consolidated and roofed to minimise the losses. On the other hand, fragmentation of scrap of composite products, especially cars, generate large amounts of lead containing waste which is landfilled.

Release of lead to soil with ammunition is reduced by legislative restraints, but the decrease is not as significant as the decrease in lead shot emission to aquatic environments, partly because use of lead shot in forests is still legal, partly because the use of ammunition for rifles and military applications has been unchanged.

The total discard of lead to deposits (including landfills) has in broad outline been unaltered. The main sources of lead to solid waste has not changed, except for batteries, which today is considered to constitute a minor part of lead in solid waste.

Substance Flow Analysis for Mercury

Jacob Maag, Carsten Lassen & Erik Hansen. 1996. Environmental Project no. 344.

The Danish EPA, Copenhagen

English Summary

A detailed assessment of the consumption of mercury divided on use areas in Denmark has been carried out. Disposal and emissions to the environment has also been quantified. The assessment is based mainly on data from 1992-1993.

The established picture on consumption and emissions to the environment for mercury in Denmark is illustrated in figure 2.1.

Figure 2.1
Mercury balance for Denmark 1992/93 (all figures in kg/year)

As stated in figure 2.1 the consumption of mercury is calculated to 6,800-9,500 kg/year, while the import of mercury as raw material and with commodities containing mercury amounted to approximately 7,000-10,000 kg/year, and the export with commodities came up to approximately 1,000 kg/year. The export comprised batteries, thermometers and flashing lights for rail road crossings.

A more detailed presentation of the use areas for mercury is given in table 2.1.

Uses

The most important intended uses include catalyst for electrolysis, mercury amalgam for dental fillings and batteries (mercuryoxide-batteries, alkaline batteries and button cells types as alkaline, zinc-air and silveroxide). Together these uses count for approximately 61% of the total consumption.

Less important uses include monitoring equipment (measurement of blood pressure, manometers etc.), electrical switches and relays (floating switches for submerged pumps, flashing lights for railroad crossings, sensors for airbags and other purposes in cars etc.), lamps (fluorescent tubes and the like), thermometers (fever thermometers and thermometers for monitoring of ship engines etc.), chemicals for laboratory purposes (COD-analysis etc). Together these uses count for approximately 16% of the total consumption.

Unintended use of mercury due to, that mercury will exist as contaminant in coal and other commodities is estimated to count for approximately 23 % of the total consumption

Table 2.1
Mercury consumption in Denmark 1992/93

Trends in consumption

The consumption of mercury is generally on retreat. In the period from 1982/83 to 1992/93 the total consumption of mercury in Denmark has been by and large halved. This development is related to, that the consumption for several important use areas (batteries, dental fillings, thermometers etc.) has been significantly reduced, while for other purposes the use of mercury has completely or almost disappeared (fungicides for seed, Kjeldahl-analysis). The regulation on mercury use in Denmark established in 1994, will most likely enhance this development.

Also with respect to the use of mercury for electrolysis the mercury consumption has decreased in this period. This fall was caused by, that the chlorine-alkali plant belonging to Dansk Sojakagefabrik was closed by the beginning of the 1990'ties, resulting in, that today only one plant using mercury for electrolysis is operating in Denmark.

Emissions/losses of mercury to the environment is quantified in table 2.2.

Table 2.2
Emissions/losses of mercury to the environment in Denmark 1992/93, (kg/year).

Link to Table 2.2

Emissions to air

The most important source for emission of mercury to air is solid waste incineration, which is assessed, in particular, be to due to the supply of mercury with batteries (most likely especially mercuryoxide batteries from photo equipment) and with dental fillings (in particular fillings in children's milk teeth). However, it should be noted, that it is difficult exactly to explain the supplies of mercury to incineration plants, as the supplies estimated are somewhat short of, what is actually registered at the incineration plants.

The second most important source for emission of mercury to air is coal fired power plants, which are estimated to count for 200-500 kg of mercury per year. Other emissions are mainly related to waste treatment and disposal.

Emissions to water

Emissions to water are due to waste water (treated) from municipal sewage treatment plants, which are receiving mercury from dental clinics and the use of mercury for thermometers and monitoring equipment.

Emissions to soil

Emissions to soil are due to, in particular, sewage sludge from municipal sewage treatment plants (dental clinics, thermometers, monitoring equipment), churchyards (dental fillings) and mercury as natural contaminant in fertilizers and agricultural chalk. It is noted, that most likely loss of mercury to soil will take place by recycling of iron- and metalscrap containing mercury switches (chest freezers, cars). It is, however, not possible to quantify this loss.

Trends Also with respect to emissions of mercury to the environment significant reductions have taken place within the period from 1982/83 to 1992/93. This is the case for emissions to air, water as well as to soil.

This development follows naturally from the decline in consumption. The reduced consumption of mercury with batteries has naturally lead to reduced emission from incineration plants, just like the stop for the use of mercury fungicides for seed heavily has reduced emissions to soil. The regulation on mercury use in Denmark established in 1994, will without doubt enhance this development.

Improved cleaning has contributed as well. This is especially the case for incineration plants, as the introduction of cleaning for acid gasses has resulted in, that approximately 50% of the content of mercury in the flue gas is separated with residual products from the flue gas cleaning process. It should be noted, that this assessment deals with the 1992/93-situation, and that acid flue gas cleaning first was fully established at all incineration plants in Denmark in 1995. The consequence is, that the emission to air from incineration plants in 1996 - everything else equal - is likely 200 kg/year lower than indicated in table 2.2.

Today, all dental clinics are equipped with filters, that partly retain particles containing mercury from the clinics sucking system and sinks. Such filters has reduced the emission of mercury from dental clinics to the sewage system. However, the efficiency of never and older filter types differs widely. Thereby, a potential exist for further reduction of emissions.

Collection and disposal/recycling

The ongoing collection of mercury and waste containing mercury is considerable. The yearly collection includes approximately 3,000 kg of metallic mercury (incl. surplus amalgam from dental clinics) and 4,200-6,200 kg of mercury with chemical waste.

Collected metallic mercury is no longer recycled in Denmark, but exported for recycling in other countries. Chemical waste containing mercury are partly deposited in Denmark and partly exported for depositing or recovering of mercury abroad.

Stock building in the society

As stated in figure 2.1 these activities result in a negative stock building of mercury in the Danish society of 3,100-7,900 kg/year. These figures illustrates, that the consumption of mercury is decreasing and that the existing stock of mercury in the Danish society (e.g. in monitoring equipment and at institutions for education) is being reduced.

The total stock of mercury in the Danish society (i.e. the mercury in use in miscellaneous products) was for 1982/83 estimated to 100-300 tons /5/. The amount of mercury removed from the stock in the period up to 1992-/93 is not known precisely, but may be roughly estimated to approximately 50 tons. Thus, the existing stock of mercury may likely be estimated to around 50-250 tons.

Substance Flow Analysis for Tin

- with Focus on Organotin

Carsten Lassen & Erik Hansen. 1997. Working Report no.7/1977.

The Danish EPA, Copenhagen

English Summary

This report presents a relatively detailed analysis of tin consumption and emissions to the environment in Denmark 1994. The report is prepared according to the Danish Environmental Protection Agency's paradigm for substance flow analysis.

The present knowledge is acquired through information from the Danish National Agency of Statistics, the Danish Productregister Database, technical literature, questionnaire to the PVC industry, private companies, and governmental institutions.

Tin balance for the Danish Society is summarised in figure 2.2.

Figure 2.2
Tin balance for the Danish Society (tonnes tin/year)

Tin consumption

The total tin consumption with manufactured goods in Denmark in 1994 is estimated at 740-1,280 tonnes. The turnover of tin in the society was somewhat higher as there aside from this was an import/re-export of tin with packaging, copper-tin alloys, and solders in electronics and auto radiators.

Metallic tin

In total the consumption of metallic tin was 640-1,000 tonnes tin. The most significant fields of consumption were tinplated containers (33% of total consumption), solder used in electronics, plumbing and sheet metal joining, auto radiators, and container seaming (32%), and copper-tin alloys (bronze) used in switches, valves and bearings (10%). Apart from uses of copper-tin alloys it was characteristic that tin was used in consumer products which were disposed of with municipal solid waste and there was hardly no recycling of tin from discarded consumer products.

Chemical compounds

The total tin consumption with chemical compounds in 1994 was 13-21 tonnes Sn. Organotin compounds constituted the main part.

Organotin compounds are defined as compounds which contain one or more organic functional groups attached to the tin atom with a relatively stable tin-carbon bond. The compounds are dependent on the number of tin-carbon bonds divided into four classes: the mono-, di- tri- and tetraorganotins. Only mono-, di- and triorganotin compounds are used in Denmark and the consumption of the three classes is summarised in table 3.

The major use of mono- and diorganotin compounds was for UV and heat stabilisers in PVC. The main uses of tin stabilised PVC were transparent rooflight sheets, tarpaulins, bottles and packaging. The consumption of tin stabilisers has had a downward trend due to substitution of PVC packaging with other materials.

Beside this, diorganotin compounds were used in low concentrations as catalysts for silicone, polyurethane foam and for a broad range of glues and paints. The total consumption with these uses is relatively small, but diorganotin compounds are used in a range of semi-manufactured goods for consumer products such as electronics, footwear, vehicles, and furniture.

Triorganotin compounds are used as a biocide in antifouling paint and as fungicides in surface and vacuum preservation of wood. In 1994 only a single organotin pesticide was used in Denmark.

The total consumption of inorganic tin compounds is estimated at 2.7-7.1 tonnes Sn. Inorganic tin compounds were used for electroplating tin-lead alloys in the electronic industry and electroplating of tin or tin-nickel on equipment for the food industry, scientific instruments etc. Moreover inorganic compounds were used for glass and ceramic glazes.

Emissions to the environment

Emissions of tin to the environment in Denmark and release to waste deposits are shown in figure 2.2.

Table 2.1
Consumption of organotin compounds with finished goods in Denmark; 1994

There are only a few available measurements of tin emissions to the air in Denmark. Emissions from the different sources are consequently estimated from emissions factors from the literature. The total emission to the air is estimated at 0.5-6 tonnes Sn. The main sources were production of iron and steel, glass, cement, ceramics, and castings, burning of coal and oil and incineration of municipal solid waste.

No data on organotin emission to the air has been available but a modest emission from solid waste incineration and glass production is expected.

Discharge to aquatic environments

The total discharge to the aquatic environment is estimated at 4-17 tonnes Sn/year. Of this, organotins constituted 2.9-4.6 tonnes Sn/year. The main sources were municipal waste water, release of organotin from antifouling paints on ships, and emission of organotin from shipyard activities.

The emission of organotin from antifouling paints can either be estimated as the emission from ships built or repaired in Denmark or as the total emission from vessels to the Danish waters. Based on the consumption of antifouling paint in Denmark, the emission is estimated at 2.9-3.8 tonnes Sn/year. The total emission to the Kattegat and the Belt Sea from vessels calling at Danish and Swedish ports or passing through the Belts in 1994 is with high uncertainty estimated at 0.2-1.4 tonnes Sn. Danish vessels are estimated to be responsible for 12-35% of this emission.

Based on preliminary studies of organotin in municipal waste water it is estimated that triorganotin in waste water constituted at most 5% of the total triorganotin discharge to the aquatic environment while at least 95% directly or indirectly was due to the use of antifouling paint.

Discharges of organotin with waste water from ship yards has been significantly reduced due to effective waste water treatment. But it is still unclear to which extent organotin is emitted with aerosols from spray-painting and dust from sand blasting. The present information indicates that these activities could contribute significantly to the total discharge of organotin compounds to the aquatic environment.

Release to soil

The total release to soil is estimated at 3-19 tonnes Sn/year. Release of organotin was due to the use of municipal waste water sludge on agricultural soil (0.1-0.9 tonnes Sn), leaching and spill of wood preservatives (0.4-1.4 tonnes Sn), use of pesticides (0.02 tonnes Sn) and emissions of dust and aerosols with antifouling paint from ship yards (0.03-0.3 tonnes Sn). The compounds which are released may be degradation products as the organotin compounds are degraded within and at the surface of the products where they are used.

Recycling

There is hardly no recycling of tin with used products. In 1994, 220-270 tonnes tin were recycled with scrap - principally from manufacturing of products. The scrap was exported. Indirectly organotin was recycled with transparent PVC sheets, but compared to the total consumption of organotin compounds recycling was rather insignificant.

Aluminium

- Substance Flow Analysis and Loss Reduction Feasibility Study

Carsten Lassen, Erik Hansen, Torben Kaas & Jørgen Larsen. 1999. Environmental Project no. 484.

The Danish EPA, Copenhagen

English Summary

The total consumption of aluminium metal with finished goods in Denmark 1994 is estimated at 72,000-105,000 tonnes. The same year, 40,000-60,000 tonnes was discarded, of which about 60% was recycled whereas the remainder was disposed of with solid waste or emitted to the environment. Solid waste disposal of aluminium in packaging made up about half of the lost aluminium metal. Some 7,300-13,000 tonnes aluminium metal ended up in refuse incineration leading to the formation of 14,000-25,000 tonnes slags. Beside aluminium metal 1.000-2.400 tonnes aluminium was consumed with chemicals and 110,000-340,000 tonnes aluminium was consumed with minerals; mainly clay minerals and coal. The major part of discarded aluminium is recycled, but the recycling process results in general in a quality deterioration of the aluminium. For selected uses the report reviews the feasibility of quality preservation and the possibilities of a reduction of the loss of aluminium from the material cycle.

Background and Aim of the Project

The present analysis made part of a project which beside this analysis includes an assessment of environmental profiles of aluminium in a life cycle perspective and an assessment of the "ecological scope" for the use of aluminium.

The background for the project is that the Danish Environmental Agency's Action Programme for Cleaner Technology 1993-1997 designated aluminium as one of the materials for each of which a survey of the environmental load in the whole life cycle of the material is to be carried out. Aluminium was designated because the metal is used in large quantities, consumption is increasing, and because parts of the material cycle have substantial environmental impact.

The Survey

The project is carried out according to the Danish Environmental Protection Agency's paradigm of substance flow analyses. The present knowledge is based on information from the Danish National Agency of Statistics, the Product Database of the Danish EPA, technical literature, private companies and governmental institutions. In the analysis all information is hold together to form an image of the total aluminium mass flow through the Danish society. An important purpose of the analysis is to point out applications which result in losses of the substance to the environment, wastewater, refuse incineration and landfills respectively. By drawing up the mass balance, independent data on sources and sinks are compared, e.g. sources of aluminium to wastewater are compared to actual analyses of the substance in wastewater and municipal sludge.

The assessment of aluminium disposal and emissions to the environment focuses on losses and emissions from uses of aluminium as metal or with chemicals, whereas the turnover of aluminium with minerals and as natural contaminant is only analysed summarily. With respect to this the analysis deviates from the paradigm.

The survey was carried out in 1996 using data representing the 1994 situation.

Main Conclusions

	The consumption of aluminium metal with finished goods in Denmark 1994 is estimated at 72,000-105,000 tonnes Al, whereas aluminium consumption with chemicals is estimated at 900-2,400 tonnes Al.
	Some 14,000-25,000 tonnes aluminium metal was lost to the environment or deposits.
	Aluminium in packaging made up more than half of the loss of aluminium metal with waste.
	A reduction of the loss of aluminium with thin packaging foils can in particular be obtained through a more differentiated view on the necessity of diffusion barriers and as a consequence eventually substitute other materials for aluminium.
	It is recommended to investigate the feasibility of collecting aluminium packaging with other metals from the households.
	Anodes for cathodic protection of ships and harbours were the principal source of non-mineral bound aluminium release to the aquatic environment, whereas he main sources of non-mineral bound aluminium to wastewater were precipitants and nonphosphatic detergents.
	Only about 60% of discarded aluminium was recycled. Due to mixing of alloying elements almost all scrap aluminium was recycled for casting alloys with a high content of alloying elements.
	If a major part of the total aluminium consumption is to be based on secondary aluminium, an increased grade of scrap aluminium will be requisite to avoid the limitations of applications of secondary aluminium caused by the mixing of alloy constituents.

Results

Aluminium Consumption

The total aluminium consumption in Denmark is represented in table 1. The aluminium metal consumption of 72,000-105,000 comprises less than a third of total consumption of aluminium. With respect to this aluminium consumption differs markedly from most other metals. This is due to the fact that aluminium occurs in high concentration in many common minerals. Aluminium in coal comprises about a third of the total aluminium consumption, and the high aluminium concentration in the residues makes coal a possible future aluminium resource.

Table 1
Aluminium consumption with manufactured goods in Denmark 1994

From an energy and resource viewpoint, the consumption of aluminium metal is not comparable to the consumption of aluminium with minerals, as extraction of the metal from the clay minerals involves a high energy consumption. The aluminium consumption with minerals and unintended uses is consequently only assessed summarily and included, as the uses with minerals influence on the drawn up balances.

Aluminium metal consumption differentiated on uses is presented in table 2. Aluminium is used for a large number of applications and there is no main application that makes up a predominant part of the consumption.

Table 2
Aluminium metal consumption with manufactured goods in Denmark 1994

Mass Balance of Aluminium

The national mass balance of aluminium is shown in figure 1. The balance only comprises uses of aluminium as metal and with chemicals.

There is no primary production of aluminium in Denmark and the country is dependent on supplies from abroad. Commodity trade across the border is represented in the left part of figure 1.

The net supply of metallic aluminium or aluminium in chemicals to the Danish society with both raw materials and manufactured goods in 1994 is estimated at 54.000-88.000 tonnes. Of this, the net import of metallic aluminium with raw materials and semi-manufactures made up the main part which based on the trade statistics can be determined relatively precisely. The total import and export with finished goods could only be estimated with high uncertainties, and the net balance is in between a net export of up to 23,000 tonnes and a net import of up to 8,000 tonnes.

In 1994 about 18.200 tonnes secondary aluminium was produced from remelted scrap in Denmark. The produced secondary aluminium was exclusively used for casting alloys and deoxidiser for steelworks.

Figure 1
Aluminium mass balance for the Danish society 1994. The production of secondary aluminium is illustrated in a simplified way as a recycling within the boundary of the country, although there is an intensive import and export of scrap. All flows are in tonnes Al.

Emissions to the Environment

In the upper part of figure 1 emissions to the air are shown.

There are no limit values for emission of aluminium to the air in Denmark, and it has not been possible to procure any measurements of aluminium in flue gasses from refuse incineration, coal and oil combustion, aluminium casting or production of cement, tile or secondary aluminium. The total emission from Danish sources is roughly estimated at 40-320 tonnes Al, of which the main sources are supposed to be refuse incineration and coal combustion. Broadly <50 tonnes Al of these could be assigned to use of aluminium as metal or with chemicals.

In the right part of the figure the release of aluminium to soil and the aquatic environment is shown.

The turnover of acid soluble (i.e. not mineral bound) aluminium with wastewater is, based on measurements of aluminium in sewage sludge, estimated at 1.100-1.800 tonnes Al. More than 90% of this was retained with the sludge. The main sources of acid soluble aluminium (not mineral bound) are assumed to be aluminium containing precipitants and nonphosphatic detergents.

The principal source of aluminium release to the aquatic environment, representing 1.100-1.400 tonnes aluminium, was anodes used for cathodic protection of ships and harbours.

In 1994 570-800 tonnes acid soluble aluminium was disposed of to agricultural land with sewage sludge. Loss of aluminium with discarded underground cables left in the ground, is estimated at 20-100 tonnes Al in 1994, equivalent to about 1% of the current consumption for this purpose.

Loss of Aluminium with Solid Waste

At the lower part of figure 1, the loss of aluminium with solid waste is shown. Most of the aluminium metal that was lost was disposed of to refuse incineration where it was oxidised under liberation of energy and ended up in the residues. It is estimated that incineration of aluminium metal lead to the formation of 14,000-25,000 tonnes aluminium oxide in residues.

As shown in table 3, aluminium in packaging constituted about half of the total loss of aluminium metal in 1994. Intended loss of aluminium as deoxidiser for steel production and cathodic protection of harbours and ships constituted about 12% of the total loss. For both packaging and cathodic protection primary aluminium is used, and at present it is not possible to use less pure secondary aluminium for these applications.

Table 3
Loss of aluminium metal in Denmark 1994

New Danish guidelines for the disposal of electric and electronic appliances will markedly decrease the loss of aluminium with these products, and the 1994 data shown in table 3 will not be representative for the present situation. However, there will still be a considerably loss of aluminium with smaller objects disposed of with municipal solid waste from households.

Industrial waste constituted about 8% of the total loss. A part of this waste was reused for production of precipitants, and there is a trend of increasing utilisation of the industrial waste.

Recycling of Aluminium

In 1994 40,000-60,000 tonnes aluminium metal was discarded or lost. Of this quite 60% was recycled. Compared to other metals like iron or copper the recycling rate of aluminium is relatively low. This is primarily due to the loss of aluminium with packaging. Of a total consumption of 7,300-11,200 tonnes with packaging it is estimated that less than 100 tonnes was collected for recycling in 1994. However, a number of collection system experiments are running at present, but efficient collection systems are difficult to realise because the aluminium is contaminated with food.

It is estimated that 27,100-37,200 tonnes aluminium was recycled in 1994. There was an intensive import and export of aluminium scrap with a net export of 8,000-17,500 tonnes Al. In Denmark 18,200 tonnes secondary aluminium was produced from aluminium scrap. Due to mixing of alloying elements broadly all scrap from discarded products was used for production of casting alloys or deoxidizer for steelworks, whereas process scrap to some extent was exported for remelting and production of new raw materials of the same composition. Due to the increasing aluminium consumption in Denmark as well as in the rest of the world the market for casting alloys can at present absorb all produced secondary aluminium.

Through repeated life cycles the quality of the aluminium alloys will deteriorate due to a mixing of alloy constituents. At present, when secondary aluminium is principally used for casting alloys, mainly iron and magnesium cause problems. If a major part of the total aluminium consumption is to be based on secondary aluminium, an increased grade of scrap aluminium will be requisite to avoid the application limitations of secondary aluminium caused by the mixing of alloy constituents.

Feasibility of reducing or avoiding the loss of aluminium

The aluminium consumption is increasing due to a number of good material characteristics as lightness, diffusion resistance, and corrosion resistance. In the present analysis no obvious uses where aluminium can be substituted by other materials have been identified.

Trade, material characteristics, recycling and substitution feasibility have been reviewed for four product groups: packaging, building materials, electronics and transportation. The following conclusions are drawn from the analyses:

Packaging: A reduction of the loss of aluminium with thin packaging foils can in particular be obtained through a more differentiated view on the necessity of diffusion barriers and as a consequence eventually substitute aluminium by other materials. Thicker foils, cans and containers are more suitable for recycling, but are collected to a very limited extent. It is recommended to investigate the feasibility of collecting aluminium packaging with other metals from the households.

Building materials: These materials are suitable for recycling, and the bulk part of aluminium from construction and demolition sites are recycled. The trend of using aluminium in more composite products in the building sector may impede recycling on the long view.

Electronics: Until now aluminium from electronics has mainly been disposed of to landfill and incineration plants or recycled via a shredding process. In the new electronic recycling plants these products are disassembled which makes sorting of the aluminium feasible. About 10% of electronic products is at present disassembled. Disassembling and sorting of the aluminium would be easier and more profitable, if the products were easier to disassemble.

Transportation: More than 95% of aluminium in cars is recycled. The alloys are in general mixed during the recycling process, and consequently characteristics are lost.

Substance Flow Analysis for Dichloromethane, Trichloroethylene and Tetrachlorethylene

Jacob Maag. 1998. Environmental Project no. 392.

The Danish EPA, Copenhagen

English Summary

This report This report is presenting the results of a national substance flow analysis (SFA) for the three chlorinated hydrocarbons dichloromethane, trichloroethylene and tetrachloroethylene for Denmark. The analysis was conducted in 1996 and 1997 and describes the situation in 1995. Investigations and reporting was undertaken by COWI Consulting Engineers and Planners AS for the Danish Environmental Protection Agency.

Special attention has been given to the use of the three substances in preparations, meaning products consisting of mixtures of substances.

Trends in consumption: Industrial use mainly

The investigations has revealed that the consumption is concentrated on traditional industrial uses, particularly of the pure substances, but also on preparations such as paint strippers and solvents for processing printing plates for the flexo technique. All identified products are mainly used professionally.

Paint strippers for domestic use

The only major use of chlorinated hydrocarbons in the households are paint strippers containing dichloromethane.

Consumption of preparations

Only a minor share of the consumption of trichloroethylene and tetrachloroethylene in Denmark is used with preparations, 5% and 3% respectively . For dichloromethane the corresponding figure is approximately 26%, due to the relative large consumption of paint strippers.

Consumption and losses of the three substances are summarised in the tables 2.4-2.6.

Losses to the atmosphere dominates

As expected, available measurements describing the losses of chlorinated hydrocarbons to the environment in Denmark is scarce. However, the few results reported on concentrations in waste water has confirmed the magnitude of the estimated discharges by this route.

The major part of the consumption is considered lost to the atmosphere by evaporation during the use. Measurements on rain water indicates that part of this will be deposited in the terrestrial and aquatic environments.

Direct discharges to waste water are deemed propable for only few uses of the substances. For all other uses, it is believed that no discharges to waste water will appear under normal circumstances.

Losses with waste It has not been possible to quantify the losses of the chlorinated hydrocarbons to hazardous waste precisely . The presented figures are rough estimates based on general knowledge on chemical characteristics and standard routines of use and disposal in the application fields in question.

For domestic waste the situation is similar. A few measurements of emissions of trichloroethylene and tetrachloroethylene from waste management plants has been found, though.

The major contributions to hazardous waste originates from use in closed or semi-closed systems, such as dry-cleaning of textiles, medical industry, laboratories and flexo plate processing.

Alternatives available

In this investigation most of the information has been retrieved from product suppliers and only to a lesser degree from users. It is the clear impression from the conducted inquiries, that alternative preparations, not containing chlorinated hydrocarbons, are commercially available, and that such products hold considerable shares of the market for several applications. It must be noted however, that it has not been part of the purpose of this investigation to evaluate if the alternative products comply with the demands of the users for efficiency and low cost.

Pure substanses vs. preparations

In these investigations the turnover of each substance is quantified separately for the pure substance (traded as such) and for the substance contained in preparations.

In figure 2.1 the flows are shown in principle (simplified). "Net import" denotes the import minus the re-export of the substance as pure and and as contained in preparations manufactured outside Denmark (respectively). As such "Export" denotes the export with preparations produced in Denmark only. "Losses" includes losses to the environment (to air, water and soil), as well as destruction and degradation in waste treatments facilities.

Figure 2.1
Flow of chlorinated hydrocarbons as pure substances and with preparations of these in the Danish society (simplified, see text)

Table 2.2
Estimated consumption and losses of dichloromethane in Denmark

Link to Table 2.2

Table 2.3
Estimated consumption and losses of trichloroethylene in Denmark

Link to Table 2.3

Table 2.4
Estimated consumption and losses of tetrachloroethylene in Denmark

Link to Table 2.4

Brominated Flame Retardants

- Substance Flow Analysis and Assessment of Alternatives

Carsten Lassen, Søren Løkke & Lina Ivar Andersen. 1999. Environmental Project no. xxx.

The Danish EPA, Copenhagen

Including 'English Summary' and 'Summary and Discussion of Substance Flow Analysis'

English Summary

The consumption of brominated flame retardants (BFRs) with end products in Denmark in 1997 is estimated at 320-660 tonnes. Tetrabromobisphenol A (TBBPA) and derivatives accounted for about half of the consumption, and the consumption of these flame retardants is increasing. The more controversial compounds, polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) accounted for approximately 1% and 9%, respectively, of the consumption with end products. A marked shift away from PBDEs has taken place in Danish production and for a part of the imported products. The knowledge on the emissions of the brominated flame retardants to the environment is still very limited. Model estimates indicate that the major source of brominated flame retardants lost to the environment is evaporation from products in use. No recycling activities are taking place for materials containing brominated flame retardants. Broadly all electronic equipment, as well as a major part of other electrical devices, contains brominated flame retardants. For two large application areas - TV sets and computer monitors - the trend of the recent years has been a shift away from the use of brominated flame retardants. This is partly due to the influence of ecolabels. Today, alternative flame retardants are available for applications that quantitatively account for the major part of the consumption of brominated flame retardants. The current knowledge of the environmental properties of the substitutes is limited, however. For a number of applications that account for a major part of the BFRs used for Danish production, substitutes are still at the developmental stage.

Background and Objectives

The term 'brominated flame retardants' cover a large number of different organic substances, all with bromine in their molecular structure. Bromine has an inhibitory effect on the formation of fire in organic materials. Flame retardants are added to plastics and textiles in order to comply with fire safety requirements.

The most widely used substances - among these TBBPA, PBDEs and PBBs - contain one or more carbon rings, making them very stable and efficient in a large number of plastics.

The chemical stability of the substances - particularly in the cases of PBBs and PBDEs - is also the reason why brominated flame retardants for years have been in focus in the international environmental debate. PBDEs and PBBs, which are the most stable of the described BFRs, are spread widely in the environment, are bioaccumulated and are accumulated in sediments, where they are only very slowly degraded.

With the aim of reducing the release of brominated flame retardants to the marine environment, Denmark has committed itself in the Esbjerg Declaration of 1993, to promote the substitution of brominated flame retardants with less problematic substances if such are available.

Recent research has revealed that some of the brominated flame retardants are emitted to the indoor environment from the products in use. Increasing concentrations of PBDEs have been observed in human breast milk.

Risk assessments on three PBDEs and HBCD have been carried out within the EU since the mid nineties. The results of the assessments of the PBDEs are expected to be presented in 1999.

No previous assessments of brominated flame retardants have been carried out in Denmark. It is the aim of this study to establish an overview of the use of these substances in products manufactured in, and imported to, Denmark. In addition the purpose of the project is to assess the possibilities of and limitation for substitution of brominated flame retardants.

Studies in other countries have shown that the use of flame retardants has an important role in saving lives. This issue - and more broadly the social advantages of the use of flame retardants - has not been covered by the present study.

The Study

This study has been carried out in accordance with the paradigm for substance flow analysis of the Danish Environmental Protection Agency. The knowledge presented is based on data from Statistics Denmark, the Danish Product Register, the literature, market analyses, public institutions as well as from private organisations and companies. In the analysis, all the information has been hold together to describe the total flow of brominated flame retardants through the Danish society.

Data on the import of brominated flame retardants with polymer raw materials for production in Denmark has been obtained through a questionnaire in co-operation with the Danish Plastic Federation.

An attempt has been made to collect information on the contents of brominated flame retardants in imported goods via trade companies and importers. This has proven difficult, as most vendors do not know, whether the products in question contain brominated flame retardants. As a consequence, the analysis for a number of product types has been based on data on the European market for flame retardants and flame retarded polymers. Based on such information, it has been possible to determine which flame retardants are likely to be used in the different types of end products.

No measurements of the concentrations of brominated flame retardants in Danish waste water and sewage sludge have been found. Similarly no measurements of emissions from production or products in use are available. No Danish studies have been made on the fate of brominated flame retardants in the waste treatment systems. Hence, it has been necessary to estimate the potential loss of brominated flame retardants to the environment considering the few available foreign analyses and model estimates. The presented estimates of losses to the environment are therefore to be considered as the author's best estimate based on the existing knowledge.

Information on alternative flame retardants, and products containing alternatives, has been obtained from suppliers of flame retardants and plastic raw materials, as well as searches on the Internet and direct contact to producers using alternatives. Brominated flame retardants account only for about 15% of the Western European market for flame retardants. For many purposes, for instance carpets and PVC, other types of flame retardants are generally used. For this reason, only the applications where brominated flame retardants are used today, have been included in the assessment of alternatives.

In order to give a first overview, potential risks related to alternative flame retardants were identified on the basis of existing reviews.

This study has been carried out in 1998/99, and the data represent the 1997-situation.

Main Conclusions

The main conclusions of the project are:

	The Danish consumption of brominated flame retardants with end products in 1997 is estimated at 320-660 metric tonnes. The consumption can be broken down to about 47% TBBPA and its derivatives, 12% PBDEs, 1% PBBs, 11% HBCD and 29% other brominated flame retardants. About 44% of the total were used as reactive constituents.
	Imported goods accounted for about 90% of the consumption with end products.
	Brominated flame retardants are used in almost all product types containing electronics, as well as in a significant part of other types of electrical equipment.
	Brominated flame retardants are not produced in Denmark. The total import of brominated flame retardants with chemicals, polymer compounds and plastic semi-manufactures for production in Denmark was 260-390 tonnes in 1997. Of this TBBPA accounted for about 54%, while PBBs and PBDEs in total accounted for only about 2%.
	For production of insulating materials in Denmark 83-130 tonnes HBCD and brominated polyetherpolyol were used.
	In Danish manufacturing of housing for electronics, the brominated flame retardants have been substituted with halogen-free flame retardants. The substitution has been driven by the purpose of avoiding antimony trioxide, which is often used in combination with the brominated flame retardants. Antimony trioxide is listed on the Danish list of hazardous substances. (brominated flame retardants are not).
	There has been a marked shift from PBDEs to TBBPA (and derivatives) in thermoplastics used in Danish production. This trend is also seen for housing of imported electronics, although PBDEs are still present in many imported products. Assessments on the overall European consumption do only indicate a decrease in the consumption of PBDEs in Northern Europe.
	Model estimates indicate that the emissions of brominated flame retardants to the environment are predominantly caused by evaporation from end products in use, whereas production processes may contribute with minor amounts. Little is known so far regarding the evaporation from end products. The actual emission rates and the fate of the evaporated substances are still uncertain.
	It is important to distinguish between additive and reactive uses. Brominated flame retardants used as additives are estimated to have a much larger tendency to evaporate to the surroundings, than substances chemically bound in the polymer structure. Examples of reactive use are the incorporation of bromine in epoxy based printed circuit boards and rigid polyurethane foam.
	Discharges to waste water from products and production processes are modest. A major part is estimated to originate from flame retarded textiles. This contribution is, however, rather small compared to other European countries, where the use of brominated flame retardants in textiles is more common.
	For a number of electronic products, no alternatives are currently available. This is reflected in the fact that the present ecolabels only have requirements regarding flame retardants for large plastic parts in the products.
	Alternatives exist for the major applications, printed circuit boards and housing.
	Most of the alternatives have been assessed only to a very limited extent. Several of the substances have been demonstrated to have undesirable environmental effects, and there is a need to establish a better overview of the environmental properties of the alternatives.

The results

The present study consists of two parts: a substance flow analysis of brominated flame retardants and an assessment of alternatives to brominated flame retardants.

Extended summary of the results and discussion of the substance flow analysis can be found in chapter 6.

The aim of the assessment of alternatives is to identify possibilities of and limitation for substitution of brominated flame retardants. Extended summary for the assessment of alternatives can be found in chapter 11.

6 Summary and Discussion of the Substance Flow Analysis

6.2 Consumption in Denmark

The total consumption of brominated flame retardants with end products in Denmark is summarised in table 6.1.

The total consumption is estimated at 320-660 tonnes.

The principal fields of application were:

	Electric and electronic equipment accounting for about 70% of the total
	Building materials accounting for about 15% of the total
	Transportation accounting for about 12% of the total

The consumption with electric and electronic equipment can be broken down to about 29% of the total consumption with printed circuit board assemblies, 21% with housing, 7% with other parts of electric appliances and machines, 2% with lighting, and 11% with products for wiring and power distribution.

The use of brominated flame retardants is very widespread. Brominated flame retardants are present in almost all products containing electronic components i.e. virtually all electronic products and means of transport and a large part of the electric products. Additionally brominated flame retardants are used in a significant part of plastics in contact with live parts in electric equipment. Switches, plugs, and sockets for lighting are only a few examples.

Unintended uses as contaminant

Natural occurrence of BFRs has not been reported. The total turnover of PBDEs with food is estimated at 0.4-0.8 tonnes per year. Fish is estimated to account for approximately half of the intake with food. The available data indicate that the turnover of TBBPA with fish is considerably lower than the turnover with PBDEs, but data on other BFRs than PBDEs and PBBs are scarce.

Specific substances The consumption of the different groups of flame retardants is estimated with high uncertainty, as specific information on the content of flame retardants in imported products has been difficult to obtain. For some applications the actual flame retardants present in the products are estimated from more general information on the consumption of flame retardants in Western Europe and other parts of the World.

Table 6.1
Consumption of brominated flame retardants with end products in Denmark 1997

Link to table 6.1

TBBPA and derivatives are estimated to account for about 47% of the total consumption. TBBPA is mainly used reactively for printed circuit boards and additively for housing of electric and electronic appliances and engineering thermoplastics. TBBPA and derivatives are estimated to account for a larger part of the total consumption than they do at the global and W. European market cf. section 3.3. The reason is that TBBPA and derivatives are estimated to account for the major part of BFRs used for housing of electronics and this may be specific for Northern Europe.

PBDEs are estimated to account for approximately 12% of the total consumption. It should be noted that the uncertainty on this value is as high as ± 50%. Major application areas are housing and engineering thermoplastics of electric and electronic equipment and plastic parts of transportation.

PBBs account for approximately 1%. Areas where the use of PBBs has been identified are engineering thermoplastics and rubber cables.

HBCD accounts for approximately 11%. Major application areas are expanded polystyrene (EPS and XPS) and textiles for automotive interior.

Other brominated flame retardants accounted for approximately 29%. Specific information of other BFRs in imported products has been difficult to obtain. Major applications are polyurethane insulation (brominated polyetherpolyol), housing of electronics (e.g. tetrabromophtalimide), transportation (e.g. tetrabromophthalic anhydride). Other BFRs may, however, be used within all application areas.

Reactive vs. additive use

When the flame retardants are used reactively and built into the polymer structure, the chemical substance per se is only present in the plastic in trace amount. The product may rather be considered a brominated thermoset with properties that are significantly different from the properties of the flame retardant compound that is used as precursor.

TBBPA used reactively for printed circuit boards may accordingly in the end products be considered another substance than TBBPA used as additive flame retardant in housing. On a global scale additive use of TBBPA has traditionally only accounted for about 10% of the total consumption . Because of the substitution of TBBPA (and derivatives) for PBDEs in housing and other applications, the additive use is estimated to account for a considerably higher part of the consumption of TBBPA with end products in Denmark.

Other main applications by which the brominated flame retardants are used reactively are polyurethanes for insulation and technical laminates based on unsaturated polyester or epoxy.

The consumption of BFRs used as reactive flame retardants can roughly be estimated at about 44% of the total consumption.

Consumer applications of chemicals

Brominated flame retardants are not marketed for non-professional use. Sprays with flame retardants for self treatment of for instance textiles in cars are available, but to the knowledge of the authors the sprays do generally contain other flame retardants.

Trends in consumption with end products

There is no previous substance flow analysis of brominated flame retardants in Denmark.

For some of the traditional major applications, TV-backplates and housing of electronics, the trend in the consumption is downward. For TV-backplates the downward trend is general to all Europe. For the housing of electronics the trend is general to at least Northern Europe.

For other applications in electric and electronic equipment - for instance printed circuit boards - the consumption pattern has been unchanged during the last years, and the total consumption of BFRs for these applications is increasing due to an increase in the consumption of the end products.

The trend in the attitude to brominated flame retardants is that many producers are looking for substitutes for brominated flame retardants, but until now substitution has only had a minor influence on the total consumption of these compounds with end products.

Consumption for production processes in Denmark

Brominated flame retardants are not produced in Denmark. For production processes they are mainly imported with plastic compounds and laminates for production of printed circuit boards.

The total import of brominated flame retardants as chemicals and with semi-manufactures for production in Denmark is shown in table 6.2.

Table 6.2
Import of brominated flame retardants as chemicals and with semi-manufactures for production in Denmark

Link to table 6.2

Consumption of plastic raw materials

TBBPA for thermoplastic polyester (PBT/PET) and brominated polyetherpolyol account for the major part of the consumption of BFRs with plastic compounds in Denmark. The thermoplastic polyesters are flame retarded with TBBPA (derivatives) or PBB, and are used for production of plastic parts for electric and electronic equipment, for instance switches, relays, parts of pumps and electromotors.

Brominated polyetherpolyol is used reactively for production of rigid polyurethane foam for insulation. HBCD is used for production of expanded polystyrene for export.

A minor part of TBBPA is used for housing of electronic equipment. BFRs are only used for a small part of the flame retarded polyamide. Polyamides with non-halogen flame retardants are widely used.

Trends in consumption for production in Denmark

A few years ago PBDE in plastics for housing of electronic appliances represented a major part of the total consumption for production in Denmark, but non-halogen flame retardants have replaced BFRs for most applications.

The consumption of PBDEs as chemical has decreased from about 20 tonnes in 1995 to about 1 tonne in 1997.

Comparison with an W. European average

In section 3.3 it was estimated that the Danish consumption of brominated flame retardants in 1997 should be approximately 600-800 tonnes if the consumption equalled the average W. European consumption. The estimated total in table 6.1 indicates that the consumption in Denmark in total may be a little lower than the average European consumption. The assessments are, however, not totally independent, as the Danish consumption within some application areas has been estimated with a sidelong glance to the W. European consumption figures.

This is in particular true with respect to the distribution of the single groups of flame retardants. A recent market analysis shows PBDEs to a large extent has been replaced by other brominated flame retardants; especially in The Netherlands, Germany and the Nordic countries. PBDEs are hardly used in Danish production and not used by large German suppliers of plastic raw materials. TBBPA and other BFRs have substituted for PBDEs in housing of electronic products on the N. European market and dominant producers of electronic products has a policy of avoiding PBDEs. Market analyses of the European flame retardant market did not show any significant decrease in the use of PBDEs from 1992 to 1996 and PBDEs accounted in 1996 for about 26% of the W. European BFR market (based on information covering 76% of the market). A recent market analysis estimates that the PBDEs only accounted for 11% of the W. European market for brominated flame retardants in 1998.

The is a very significant difference between the consumption of BFRs in Danish production of plastics parts and the distribution of BFRs on the W. European market. PBDEs in Danish production only accounted for about 2% of the total BFR consumption in 1997 in comparison to approximately 26% and 11% of the W. European market in 1996 and 1998, respectively.

6.2 Emission and Disposal to the Environment and Landfills

Based on model considerations, the total emissions from Danish sources in 1997 have been estimated as follows:

	Emission to the air: 0.2-1.6 tonnes
	Discharge to aquatic environments: 0.005-0.07 tonnes
	Release to soil: 0.03-0.3 tonnes

The estimated emissions to the environment and disposal to landfills are shown in table 6.3.

Table 6.3
Estimated emission of brominated flame retardants to the environments and disposal to landfills in Denmark 1997

Emission to the air

There are no Danish measurements of emission of brominated flame retardants. Hence, all estimates have been based on models and measurements from other countries.

The significance of the emission of brominated flame retardants from products in use has been demonstrated by chamber experiments and measurements in the indoor environment, but the actual rates are very uncertain. Similarly emissions from production processes have been demonstrated by environmental samples from the vicinity of production sites.

Based on model considerations evaporation from products in use and during production is estimated to be the major sources of emission of the flame retardants to the air. The emission of flame retardants used reactively is estimated to be insignificant, and PBDEs and other additively used flame retardants account for the major part of the emission.

When emitted the flame retardants will tend to adsorb to solid surfaces and particles in the air. The dust particles may be released to the environment by airing, end up in vacuum cleaning bags or attach to the interior of appliances. Dust attached to the interior of appliances may be released by dismantling of the appliances.

Discharge to waste water Although the use of brominated flame retardants with protective clothing in Denmark compared to other countries is very limited, laundry of clothing with BFRs is estimated to be one of the major sources of brominated flame retardants to waste water.

Roofing foils and particles containing brominated flame retardants - initially evaporated to the air from production processes and products in use - are estimated to be other major sources of brominated flame retardants to waste water.

Discharge to the aquatic environment

Brominated flame retardants in waste water will tend to follow the sludge. The total discharge to the aquatic environment with waste water effluents is estimated to be <0,068 tonne. As is the case with other organic compounds following the solid phase, the occasional discharges by heavy rainfall bypassing the treatment plants may account for a significant part of the total discharge to the aquatic environment.

Compared to the potential deposition of BFRs from the air, the discharge with waste water is presumably small. The potential deposition of emitted substances will be dependent on the atmospheric stability of the substances. PBDEs seem to be much more stable in the atmosphere than TBBPA and PBDEs emitted to the atmosphere may be spread over long distances.

Emission to soil The only identified source of release of brominated flame retardants to soil is spreading of municipal sludge on agricultural soil. The flame retardants may to some extent be degraded during the digestion of the sludge, but data are not available for a quantification of the degradation.

Solid waste incineration In total 170-360 tonnes brominated flame retardants were disposed of to solid waste incineration. During the incineration the flame retardants will be destructed. Analyses of the fate of other organic compounds during incineration show that trace amounts of the compounds will pass the combustion chamber and end up in residuals from the incineration. For phthalates for instance up to 0.1% passes through the combustion chamber.

Flame retardants passing the combustion chamber may act as precursor for formation of brominated and mixed halogen dioxins and furans.

Landfilling In total 90-200 tonnes brominated flame retardants were disposed of to landfills. Flame retardants in products disposed of to landfills may in the long term be released to the air or landfill leachate. Measurements of brominated flame retardants in landfill leachate have not been identified. It is not known to what extent the flame retardants will be degraded within the products or in the soil in the immediate vicinity of the products from where they are released.

6.3 Substance Flow Balance for Brominated Flame Retardants

A schematic representation of the estimated flow of brominated flame retardants through the Danish society is shown in figure 6.1.

Import/export

Approximately 90% of the electronic products produced in Denmark are exported. Building materials is the only major application area of brominated flame retardants where domestic production accounts for a significant share of the consumption; and still the domestic production account for less than half of consumption. It is roughly estimated that imported products account for approximately 90% of the consumption of brominated flame retardants with end products.

Figure 6.1
The estimated flow of brominated flame retardants through the Danish society in 1997

There is at present no recycling of brominated flame retardants with plastics from discarded products. Production scrap is recycled for the same applications as the primary materials.

There are no Danish measurements of atmospheric deposition of brominated flame retardants. Data on atmospheric deposition have neither been identified in the literature.