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Possible Control of EU Priority Substances in Danish Waters

6 Assessment of lead

• 6.1 Definition of the reference state
  • 6.1.1 Introduction
  • 6.1.2 Main uses and pollution sources
  • 6.1.3 Releases to and state of the aquatic environment
  • 6.1.4 Existing legislation/regulation and their impact
  • 6.1.5 Conclusion on the need for further regulation
• 6.2 Possible reduction/elimination measures
  • 6.2.1 Technical measures to reduce/eliminate lead
  • 6.2.2 Possible synergies with other (priority) substances
• 6.3 Economic Assessment
• 6.4 Conclusion regarding lead
• 6.5 References

6.1 Definition of the reference state

6.1.1 Introduction

Lead (CAS no. 7439-92-1) is an element and is therefore not degradable in nature. Besides metallic lead, there are also a number of lead compounds that must be considered.

Environmentally, lead is a heavy metal with high toxicity. Lead and many lead compounds have very low water solubility. However, the solubility of compounds such as lead chloride and lead nitrate is high. Generally, lead is not considered to be mobile in soil. Lead bioaccumulates in the skeleton and wet tissue in mammals and in aquatic algae and invertebrates /1/.

6.1.2 Main uses and pollution sources

In Denmark, lead is used for many different purposes. It is in reality necessary to distinguish between:

• Intentional uses as lead metal;
• Intentional uses as lead compounds;
• Un-intentional "uses" as contaminant in other materials.

Table 6-1
The most important applications of lead in Denmark and the consumption in year 2000 just before the lead ban (see 6.1.4) entered into force.

* Wheel balancing weights (76-160 tons), ammunition (110-200 tonnes), Radiation protection (42-450 tonnes) and miscellaneous other uses.

** Lead oxide paint (0.5-2 tonnes), glazing (40-150 tonnes), fireworks, siccatives and several other uses.

Today the lead ban must be assumed to have resulted in a substantial reduction in the uses of lead in building materials. Apart from this, the use of lead for angling equipment and for most applications of chemical compounds (lead glass for cathode ray tubes is an important exemption) has by and large ceased.

The most important pollution sources of lead releases to the environment may briefly be listed as follows:

Air
Air emissions from fireworks, waste incineration, metal foundry activities, metal refining and recycling as well as incineration of fossil fuels. Total annual air emissions in 2000 in Denmark were estimated at 3-17 tonnes /2/.

Water
Fishing equipment, cable sheets, yacht keels, lead oxide paint together with discharges from sewage treatment plants and stormwater drainage. Total water releases in 2000 in Denmark were estimated at 170-690 tonnes /2/.

Soil
Abandoned cables, ammunition are the main contributors. To this may be added paint residues, phosphate based fertiliser, agricultural chalk, sewage sludge and several other sources. Total annual releases to the soil in 1996 in Denmark were estimated at 470-2200 tonnes /2/.

6.1.3 Releases to and state of the aquatic environment

The most important sources of direct release to the aquatic environment are fishing equipment and cable sheets, lost or abandoned. It is, however, important to note, that these sources contributes only marginally to the amount of lead dissolved in the sea or in freshwater. As a main rule this lead will be buried in sediments. However, there are important exemptions from this rule such as e.g. lead weights on fishing equipment that are dragged along the bottom or sinkers before they end in erosion zones in which wear is possible. So far, it has not been quantified to what extent lead ending in the water environment with fishing equipment and cables dissolve and thereby become biologically available.

The story of yacht keels is very similar to fishing equipment and cable sheets. Occasionally, yachts will sink but to what extent the lead is becoming biologically available has never been quantified.

The consumption of leadoxide paint is small in Denmark today, but losses to the aquatic environment still occur, partly from residues from ships treated with lead-oxide paint some 20 to 40 years ago, and partly from ships treated in other countries where the use of lead-oxide paint is not restricted to the same extent as in Denmark. There are no investigations allowing this source to be quantified.

In 2000, the total release of lead to the aquatic environment from municipal sewage treatment plants and stormwater outlets were estimated to 2.5 - 6.8 tonnes. The lead must be assumed to be biologically available, but will to some extent deposit as sediment close to the outlets. The dominant source is corrosion of lead flashing and lead roofing on buildings. Minor sources to consider include wear of brake linings, pigments and siccatives in paint, corrosion of galvanized surfaces and atmospheric deposition.

Atmospheric deposition also contributes directly to lead in the aquatic environment. The deposition in 2000 for the Danish internal waters was estimated at 26 - 48 tonnes /2/.

Table 6-2

Monitoring data for lead (average values). The values in parenthesis are the 95% percentiles.

Sources: /3/,/4/,/5/,/6/.

*             Average value of 50% percentile values for five Danish freshwater streams.
**          Average value of 50% percentile values for five Danish lakes.

Based on the median values in sewage and in stormwater runoff presented in table 6-2, the total Danish release of lead to the aquatic environment can be estimated at about 1200 kg/year and 2600 kg/year respectively.

EQS proposal

The proposed water quality criteria (EQS) for lead is AA-EQS = 7.2 μg/l (all surface waters) while no MAC-EQS has been defined in the proposal (stated to be "not applicable").

The background concentration in freshwater used in the preparation of the EQS proposal for lead was 0.2 μg/l ("dissolved"), a value determined for the river Rhine.

6.1.4 Existing legislation/regulation and their impact

Statutory Order no. 1012 of 13 November 2000 from the Ministry of the Environment on prohibition of import and marketing of products containing lead.

This Order prohibits the import and sale of products, in which lead is present as chemical compound in concentrations above 100 ppm in homogeneous materials. A number of exemptions to the ban have been granted. Also, a number of products made of metallic lead are banned, including roofing and flashing on buildings and fishing equipment.

Assessment

The Order restricts a number of very important sources. It must be emphasised that the Order does not prohibit the use of existing equipment, for which reason existing equipment will continue to cause releases until the equipment for other reasons (wear and tear or technological outdating) is disposed of. The following limitations should be considered important:

• Lead restrictions in fishing equipment should take full effect in 10 to 20 years, assuming that substitutes for all types of commercial fishing equipment are actually developed and marketed. Equipment exposed to significant wear will be replaced relatively quickly while the use of equipment not significantly exposed may continue many years ahead.
  
  Regarding lead for flashing one may note that the use of lead for reconstruction and repair work is still allowed. Furthermore, the effect will only be seen in the long-term perspective as the lifetime of e.g. flashing is in reality determined by the lifetime of the windows or chimneys for which the flashing is used. This means that the full effect will probably not be achieved until 20 to 40 years from now. In the case of lead roofing it must be expected that exemptions from the ban will be granted for historical buildings such as churches, which account for the dominant part of the consumption. A possible effect cannot be expected until in a distant future.
• Lead restrictions on fireworks will produce an immediate and profound effect, only limited by the possible illegal import of fireworks from other countries.

Furthermore, lead restrictions on chemical compounds used in paint (pigments as well as siccatives) can be expected to produce an effect, which will influence release to wastewater and stormwater. Further lead restrictions may also impact the amount of lead released to the air from waste incineration plants and miscellaneous manufacturing activities in Denmark and abroad. However, the effect of restrictions will be limited and only manifests itself slowly in the coming 20 50 years.

The stock of lead in Danish society is huge, and so far it is only Denmark that has placed far-reaching restrictions on the use of lead. Thus, it is not likely that releases of lead with wastewater and stormwater and with atmospheric deposition to the Danish internal waters will be significantly reduced within the next 10 to 20 years. It is noted that DEPA is currently considering whether and in what way it will be necessary to tighten lead restrictions presently established by the Order.

Statutory Order no. 1272 of 17 December1996 on guns and ammunition allowed for hunting etc.

The use of lead shot for hunting and sports shooting has been banned since 1996. However, lead bullets for rifles etc are still allowed.

Assessment
This Order reduces the amount of lead released to agricultural soil and forest soil and thereby eventually also the amount of lead leached from soil to fresh water bodies.

Statuary Order no. 1008 of 12 October 2004 from the Ministry of the Environment on import and sale of electric and electronic equipment.

Equipment containing lead, cadmium, mercury, chromium (VI), polybrominated biphenyls (PBB) or polybrominated diphenylethers (PBDE) is prohibited from 1 June 2006. Some exemptions for lead have been granted.

Assessment
This Order implements the EU RoHS Directive in Denmark. The Order has just entered into force all over Europe, and it will have a significant global impact. The Order will reduce the amount of lead directed to waste incineration plants in Europe with a delay of 5 to 15 years depending on the products in question. While the direct effect of the Order on releases from waste incineration is limited, the Order may have an important set-off effect due to the fact that the knowledge of alternatives is extensive and widespread. Thus, the RoHS Directive may have a very far-reaching effect on releases from waste incineration although the effect lies 10 years ahead. It is noted that the RoHS Directive supplements the EU ELV-directive, which limits the use of lead in vehicles. Taking into account an anticipated delay of 15 to 20 years, the Directive will reduce releases from scarp-based steel plants and to some extent waste incineration plants all over Europe.

Statutory Order no. 489 of 12 June 2003 from the Ministry of the Environment on cosmetic products.

The order prohibits the use of lead and compounds in cosmetics, apart from lead acetate which is allowed for hair colouring.

Assessment

The order has no significant impact on the aquatic environment since the consumption of lead for cosmetics is insignificant.

Statutory Order no. 298 of 30 April 1997 from the Ministry of the Environment on certain requirements on packaging

This sum of the content of lead, cadmium, mercury and chromium (VI) present in packaging materials to be used in Denmark must not exceed 100 ppm by weight.

Assessment
Limiting the amount of lead used in packaging materials also reduces the amount directed to waste disposal with products, which, in turn, limits releases from waste incineration etc.

Other regulation relevant for lead includes:

• Statutory Order no. 655 of 27 June 2000  on recycling of residual products. and soil in building and construction work.
• Statuary Order no. 162 of 11 March 2003 on waste incineration plants.
• Statuary Order no. 623 of 30 June 2003  on application of waste products for agricultural purposes.

Assessment

The Orders may have a direct impact on the release to the aquatic environment depending on how the rules are actually established.

6.1.5 Conclusion on the need for further regulation

The concentrations of lead in sewage and stormwater discharges presented in table 6-2 show that no initial dilution is required for sewage effluent to comply with the AA-EQS, even for the 95% percentile value of treated sewage effluent. For stormwater a modest dilution of about 2.4 times is required to comply with the AA-EQS (the correct way would be to compare with a MAC-EQS, which, however, has not been defined).

When further considering that the values in table 6-2 represent the total content of lead while the EQS are for the dissolved fraction (which constitutes only a minor part of the total concentration), it is assessed that lead does not pose problems with regard to compliance with the proposed AA-EQSs.

Further, the existing regulation will slowly reduce the releases of lead to the aquatic environment. It is roughly estimated that the current, biologically available contributions to the aquatic environment in Denmark by 2015 might be reduced by 10 to 30 %.

In conclusion, there appears to be no need for further progressive reduction in Scenario A. With regard to Scenario B, the slow but steady reduction of lead in releases and discharges into the (aquatic) environment resulting from the existing regulatory measures can be interpreted as continued "progressive reduction" beyond the EQS compliance level.

Lead is not classified as a priority hazardous substance. Therefore, there is no obligation to completely cease/phase out emissions, discharges and losses.

6.2 Possible reduction/elimination measures

6.2.1 Technical measures to reduce/eliminate lead

Generally, in these years a significant effort is invested in Denmark and via the EU RoHS and ELV Directives to substitute lead for many purposes, and it is not possible to bring forward proposals for substitution of lead that within the short time perspective available would significantly reduce any further the amount of lead directed to the aquatic environment in Denmark. Naturally, it could be proposed that existing lead flashing and lead roofing on buildings in Denmark be replaced with other materials within e.g. five years. While this proposal actually would have a significant impact on the release of lead to the aquatic environment, it is, however, hardly realistic due to the practical and economic consequences.

Therefore, if further measures to reduce releases of lead to the aquatic environment are requested, the primary additional option in the shorter term seems to be:

• The reduction of releases of lead with stormwater by arrangements detaining suspended solids. Such arrangements will actually be effective against lead from corrosion of flashing and roofing as well as atmospheric deposition and other sources.

6.2.2 Possible synergies with other (priority) substances

The dominant source of release of lead into the aquatic environment appears, as mentioned in section 6.1.3, to be stormwater runoff from separate systems. Therefore, an initiative to reduce this input could be considered though it is considered technically as well as economically unrealistic to introduce measures specifically for lead in stormwater runoff.

However, the majority of the PS/PHS including lead are characterised by properties such as lipofilicity and significant sorption onto particulate (organic) matter. Therefore, it is assessed that technological measures that aim to detain suspended particles in surface runoff will significantly reduce the loads of lead and many other PS/PHS on the aquatic environment.

Since this type of measure is not substance specific, it is described technically and assessed economically in a separate chapter (Chapter 13).

6.3 Economic Assessment

No substance-specific economic estimations are relevant since there is no need for action in neither implementing Scenario A nor Scenario B.

The cost of general action against suspended matter/pollutants in stormwater runoff is estimated after the substance-specific chapters in this report.

6.4 Conclusion regarding lead

According to the monitoring data available, the concentrations of lead in various discharges as well as in surface waters do not pose a problem in relation to compliance with the proposed EQS values. Stormwater discharge is the largest direct source of lead emitted to surface waters in Denmark.

It is concluded that there is no need for further national regulatory measures in Scenario A. For Scenario B the ongoing reduction of lead in releases and discharges resulting from the existing regulation can constitute the required progressive reduction beyond the EQS level.

Therefore, it is concluded that implementation of the requirements in Scenario A or Scenario B will not imply additional costs on Denmark with regard to lead.

6.5 References

/1/ Hansen, E.; Lassen C. (2003). Lead review. Nordic Council of Ministers, Copenhagen.

/2/ Massestrømsanalyse for bly 2000. Miljøprojekt Nr. 789, 2003. Udført for Miljøstyrelsen af C. Lassen, C. Lübeck Christensen og S. Skårup, COWI A/S.

/3/ GEUS (2004). Grundvandsovervågningen 2003.

/4/ Miljøstyrelsen (2004). Punktkilder 2003.

/5/  Bøgestrand, J. (red.) (2002): Vandløb 2001. NOVA 2003. Danmarks       Miljøundersøgelser. - Faglig rapport fra DMU 422 : 39 s. (elektronisk).

/6/  DMU (200¤). Søer 2003. Faglig rapport fra DMU nr. 516 (elektronisk).

/7/  Hansen, E. , Brønnum, J. (1998) Bly - anvendelse, problemer, den videre indsats. Miljøprojekt nr. 377/1998. Miljøstyrelsen.

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Version 1.0 August 2007, © Danish Environmental Protection Agency