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Recycling of Waste Electronic and Electrical Equipment (WEEE)

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According to the EC (19 November, 2008) “waste means any substance or object which the holder discards or intends or is required to discard.” Recycling materials and products – that are considered waste - is an ancient practice which shows that in times of resource scarcity (i.e. shortage of virgin materials) societies attach more economic and societal value to their own waste. This implies that throughout time the definition of waste can change as well. Generally speaking longer use or re-use of materials and products this is often mainly to cover a society’s needs.

To put it differently, recycling is a process which reconsiders the current life cycle of creating products and materials and associated process and final waste. Ideally, products and materials should be designed, produced, used and disposed in such a way that they can be completely re-used and/or recycled effectively and efficiently. There are many waste types, such as basic materials (i.e. glass, paper, steel, aluminum, construction minerals and plastic but also water), hazardous and chemical wastes, but also end-of-use waste products (i.e. e-waste, furniture, cars and textiles) that can be re-used or recycled.

Several technology descriptions regarding recycling can be found on ClimateTechWiki such as Advanced paper recycling and general recycling. While these descriptions cover a wide variety of recycling methods and waste management options, Waste Electrical and Electronic Equipment (WEEE) requires an individual description due to the particular characteristics of the waste. Also called electronic waste, e-waste or e-scrap, WEEE is a fast growing waste stream and describes loosely discarded, surplus, obsolete, or broken electrical or electronic devices and is often considered hazardous waste. WEEE comprises of a range of electrical and electronic items such as: refrigerators, IT and telecommunications equipment, freezers, washing machines, medical equipment, televisions, etc. Therefore, sources of WEEE are all users of electrical and electronic equipment from all sectors.

Due to the fast growing nature of the WEEE and its potentially hazardous qualities it has been qualified as a priority waste stream by the European Union. Disposal of WEEE is often inadequate which causes serious health and pollution problems.

Introduction top

The main components of WEEE, in terms of weight, are iron and steel followed by plastics (EEA, no date). As can be seen, iron and steel are the most common materials found in electrical and electronic equipment and account for almost half of the total weight of WEEE. Plastics are the second largest component by weight representing approximately 21% of WEEE. Non-ferrous metals including precious metals represent approximately 13% of the total weight of WEEE and glass around 5%. 

illustration © climatetechwiki.org

Figure 1: The composition of WEEE by weight. Source: EEA, no date

Transboundary shipment of WEEE - Criticism of inadequate disposal

The Basel Convention on the Control of Transboundary movements of Hazardous Wastes and their Disposal of the UN governs imports and exports of hazardous wastes, which includes WEEE (Basel, 2009). Importantly, the convention underlines that shipment of such waste to developing countries does not constitute environmentally sound management as required by the Convention and specifically prohibits the export of hazardous wastes from OECD countries to non-OECD countries. However, the disposal of WEEE is often criticized by environmental organizations, which claim that a significant portion of the WEEE is transported to developing countries (BAN, 2002, Greenpeace, 2008) In these countries, processing of WEEE is often inadequate and hazardous, as is illustrated in video 1. The inability to follow e-waste streams is a serious problem in the enforcement of the policy prohibiting export of certain hazardous waste types to non-OECD countries (EEA, 2009). Knowledge of the final destination of a substantial part of used electrical and electronic equipment and e-waste is very limited (EEA, 2009).

See video

Video 1

Feasibility of technology and operational necessities top

Out of the wastes requiring management, WEEE is one of the most complex due to the wide variety of products ranging from mechanical devices such as hair dryers to highly integrated systems such as computers and mobile phones (EEA, 2003). Several key issues concerning WEEE management are identified as operational necessities for effective WEEE recycling.

Operational necessities

1) Collection infrastructure - for waste management purposes it is important to collect and separate different types of WEEE according to the subsequent waste treatment and recycling processes. According to the European Environment Agency (EEA), different categories of WEEE should be created (EEA, 2003):

a) refrigerators/freezers to enable separate treatment of CFC;
b) TV sets, monitors to enable special treatment of circuit boards and parts containing flame retardant;
c) lighting equipment for mercury recovery;
d) large white goods. After removal of capacitor that might contain PCB the ferrous, non-ferrous and plastic fraction can be recycled directly.

2) Dismantling and separation - the important first step for reducing amounts of WEEE and emissions from WEEE treatment. To improve from the situation in which a large portion of WEEE is either landfilled or incinerated several measures can be taken: 

a) Tools for dismantling should be developed and improved, in order to automate the dismantling process and to increase the segregation of materials in this first step.
b)  Information for the recyclers about the location of parts containing dangerous substance and how they can be recognised should be provided.
c) The shredder process is the most problematic step in the pre-treatment chain,particularly when the input is not dismantled. Although this process is designed to facilitate material separation (ferrous material, non-ferrous and plastic) no pure fractions are obtained so that significant quantities of dangerous substances are dispersed to all fractions. This causes problems in the subsequent recycling facilities. Therefore efforts should be made to improve the process technology and to develop alternatives to this process.
d) The shredder residues are not recyclable so this fraction should be incinerated in well-controlled plants or used after further treatment for energy recovery in plants with high standard flue gas cleaning systems.
e) In order to reduce the amount of shredder residues, easily accessible parts should be removed before shredding.

3) Improvement of treatment processes - A high percentage of WEEE is still treated in municipal waste incinerators and an increasing amount is processed in industrial facilities for recycling purposes. These facilities should be equipped with appropriate abatement technologies.

Status of the technology and its future market potential top

Different models for electronics recycling exist. This section will briefly discuss the recycling system model of the European Union. First, general characteristics of such models are identified.

Electronics recycling system models

The steps of different electronics recycling system models are similar and can be placed in five groups (OTP, 2006):
a) To define the products to be included in a recycling program. The number of covered items has consequences for the size of the collection program required and, if a fee is collected at the point of sale or at the time of disposal, the administrative costs for retailers and/or collection points. 

It is possible to start simple with a limited number of products covered and then add products later on. Several recycling programs have followed this approach. The main advantage of this approach is that the program can be phased in slowly and is simpler to manage in the beginning compared to a more comprehensive approach. This simplicity arises from the limited number of stakeholders involved in the program. In addition, it is easier to introduce design and recycling incentives that can be specifically targeted to a set of products.

The other approach is to implement a more comprehensive approach. Several advantages are associated with a comprehensive product coverage. First, starting with a broad product coverage would bring all the stakeholders to the table, eliminating the need to have to try to fit in new industry sectors later. Second, electronic and electrical equipment has the characteristic of convergence. Functions of products such as cameras, music systems and phones converge into a single product. In a comprehensive approach, the companies making these products are a part of the product recycling and stewardship plan from the beginning. Moreover, due to convergence, it is not always easy to determine the category a product fits into. Third, a comprehensive approach provides a higher volume of product to recyclers. This is likely to reduce costs, increase opportunities for creating uses for the recycled products and create markets to sell them at. Fourth, the creation of a recycling program requires administrative infrastructures. It might be more efficient to set up these administrative infrastructures, with associated costs, only once. Finally, educating the consumers or the disposer of the product is easier with a comprehensive list of products covered since consumers may not remember which items are allowed and which are not.

b) To collect the used product from the consumer and transporting it to a recycler. The Office of Technology Products study indentified several techniques for collection points: curbside pick up, local government drop-off centers, ongoing drop off at retailers of electronic products, one-for-one takeback by retailers, producer-established drop-off centers, mail-back to producers, ongoing drop off at non-profits or other private sector participants, and sporadic collection events.

c) To actually recycle the product. The business models for residential e-waste have proved less successful than for commercial e-waste. While commercial e-waste is generally in working condition, residential electronics are often too old or broken to be of much use.

d) Financing each step of the system (discussed in detail in the financial requirements and costs section below).

e) To create a market for recycled materials. Whether electronics recycling can ever be profitable and market driven without the payment of additional recycling fees revolves around how much demand there is for the resulting recycled materials and whether the recycled material can compete on cost with the original manufactured material. Creating a market for the recycled product at a competitive price has been a problem in a number of industries.

European Union

The European Commission has characterised WEEE as a priority waste stream due to its potentially hazardous nature, the consumption of resources in its manufacture and its expected growth rates (EEA, no date). As one of the fastest growing waste streams, expected to grow with between 3 and 5 % each year, WEEE makes up about 4 % of municipal waste (EEA, 2003). This is approximately three times as fast as average municipal waste. With these growth rates, WEEE is expected to double in 12 years (EEA, 2003). Rapid technological development, especially in information technology (IT), causes the high growth rates. In 2003, it was determined that a large proportion of WEEE was disposed of in landfills or incineration plants in the EU (EEA, 2003).

Two main Directives apply in the EU regarding WEEE: a) the Directive on Waste Electrical and Electronic Equipment and its amendments; and b) the Directive on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment and its amendments.  

The EU recycling system model is an example of a comprehensive approach, as illustrated in Table 1 (OTP, 2006). The Directive on WEEE aims to a) prevent WEEE, b) reuse, recycle and recover such wastes to reduce the disposal of such wastes, and c) improve the environmental performance of all operations involved in the lifecycle of WEEE (EEA, 2003). The WEEE directive is based on the principle of producer responsibility (ETP/SCP, 2010). As such it contains several instruments that are typically associated with this principle: producers' take back mandates, source separations/collection requirements, collection/recycling/recovery targets and information provision requirements (ETP/SCP, 2010). The aim is to provide industry with incentives to design electrical and electronic equipment in an environmentally more efficient way, taking waste management issues into consideration (EEA, 2003).

Table 1. The ten categories of WEEE covered by the WEEE directive in the European Union. Source: OTP, 2006)
CategoryExamples/description
Large household appliancesWashing Machines, Stoves, Refrigerators, etc.
Automatic dispensersMachines that deliver products such as warm beverages
Consumer equipmentTelevisions, stereo, radio, etc.
Sports and leisure equipment, toysvideo games, model trains, etc.
Small household applianceshair dryers, toasters, etc.
Information and telecommunication equipmentComputers, calculators, cellular phones, etc.
Monitoring equipmentControl panels, thermostats, smoke detection devices, etc.
Lightinglamps
Medical devicesRadiology equipment, ventilators, etc.
Electrical and electronic toolssewing machines, drills, saws, etc.

Potential of WEEE recycling 

The 2003 EEA study regarding the quantity and treatment methods of WEEE concludes that a "large WEEE recycling potential exists which can significantly contribute to a reduction of the amounts of dangerous substances emitted as well as the recovery of considerable quantities of valuable materials" (EEA, 2003).  

How the technology could contribute to socio-economic development and environmental protection top

Next to the general advantages of recycling as discussed in the ClimateTechWiki waste management description such as more efficient use of resources, reduction of energy use, and increased employment, proper management of WEEE has several additional advantages.

The Basel Action Network (BAN) study identifies several environmental and occupational issues with improper waste management of WEEE in developing countries as illustrated in Table 1 (BAN, 2002). Clearly, improper management of WEEE results in substantial hazards in both the occupational domain as well as the environmental domain. Proper recycling of WEEE, within a recycling system model, would reduce these hazards.

Table 1. Potential environmental and occupational hazards from different waste treatment processes witnessed in Guiyu, China (BAN, 2002)
Computer / e-waste componentProcess witnessed in Guiyu, ChinaPotential Occupational HazardsPotential Environmental Hazards
Cathode Ray Tubes (CRTs)Breaking, removal of copper yoke and dumping- Siliciosis
- Cuts from CRT glass in case of implosion
- Inhalation or contact with phosphor containing cadmium or other metals

Lead, barium and other heavy metals leaching into groundwater, releaase of toxic phosphor

Printed Circuit BoardsDe-soldering and removal of copper chips- Tin and lead inhalation
- Possible brominated dioxin, beryllium, cadmium, mercury inhalation

Air emissions of same substances

Dismantled printed circuit board processing

Open burning of waste boards that have had chips removed to remove final metals

- Toxicity to workers and nearby residents from tin, lead, brominated dioxin, beryllium, cadmium, and mercury inhalation
- Respiratory irritation

- Tin and lead contamination of immediate environment including surface and groundwaters.
- Brominated dioxins, beryllium, cadmium, and mercury emissions

Chips and other gold plated components

Chemical stripping using nitric and hydrochloric acid along riverbanks

- Acid contact with eyes, skin may result in permanent injury
- Inhalation of mists and fumres of acids, chlorine and sulphur dioxide gases can cause respiratory irritation to severe effects including pulmonary edema, circulatory failure, and death.

- Hydrocarbons, heavy metals, brominated substances, etc. discharged directly into river and banks.
- Acidifies the river destroying fish and flora

Plastics from computer and peripherals, e.g. printers, keyboards, etc.

Shredding and low temperature melting to be reutilized in poor grade plastics

Probable hydrocarbon, brominated dioxin, and heavy metal exposures

Emissions of brominated dioxins and heavy metals and hydrocarbons

Computer wires

Open burning to recover copper

Brominated and chlorinated dioxin, polycyclic aromatic hydrocarbons (PAH) (carcinogenic) exposure to workers living in the burning works area.

Hydrocarbon ashes including PAH's discharged to air, water, and soil

Miscellaneous computer parts encased in rubber or plastic, e.g. steel rollers

Open burning to recover steel and other metals

Hydrocarbon including PAHs and potential dioxin exposure

Hydrocarbon ashes including PAH's discharged to air, water, and soil

Toner cartridges

Use of paintbrushes to recover toner without any protection

- Respiratory tract irritation
- Carbon black possible human carcinogen
- Exposure of cyan, yellow, and magenta toners with unknown toxicoity

Emission of cyan, yellow, and magenta toners with unknown toxicity

Secondary steel or copper and precious metal smelting

Furnace recovers steel or copper from waste including organics

Exposure to dioxins and heavy metals

Emissions of dioxins and heavy metals

Climate top

In general, there is a significant potential for reducing GHG-emissions through recycling processes, due to reduced process energy consumption. Primary production processes for intermediate products such as aluminum production require large amounts of energy input to melt the raw material (i.e. bauxite). Recovering and melting secondary aluminum requires much less energy as the scrap aluminium is already of high purity (as compared to bauxite). Lower energy consumption in turn implies lower CO2-emissions. For many other recycling processes, such as glass, paper, plastics, etc. a similar argument can be made.

The GHG impact of the production of other waste categories, such as old washing machines, computers, mobile phones, etc. can theoretically also be significantly reduced by means of improving the production processes. However, as most e-wastes also use energy during the user stage the efficiency of the appliance is also an important factor to consider when assessing the GHG-impact of electronic products during their life cycle.

Financial requirements and costs top

The economics of waste management practices and specifically recycling activities are often a crucial factor in successful adoption of a new process or technology. In general, there are many factors that shape the financial and economic environment for recycling initiatives. In some cases basic legislative changes, such as closure of a nearby landfill site or a regional ban on landfilling can make recycling more attractive as the costs of waste disposal go up. Other general examples that change the competitive environment are subsidies and taxes for specific technologies, such as waste incineration. In some areas in Europe, where landfilling is banned waste incineration has gained significant attention in recent years. New and more innovative recovery and recycling practices have to ready to compete with the already proven practice of waste incineration.

Given the wide variety of waste types a multitude of recycling processes is possible. Therefore it is difficult to provide clear-cut cost figures for recycling practices. The economic viability of recycling can only be proven on a case-specific basis, as the local context is one of the crucial factors for investment decisions. For example, investment costs relate to the commercial loan interest rates (possibly with risk premium for novel business models) charged by local financial institutions and the economic and monetary stability of the country of investment. Additionally, the costs of labor for construction as well as local availability of construction materials and machinery determine the financial requirements and costs for the investor.

It is in the policy makers interest to try and stimulate the various actors in the market to start to invest in recycling. One of the main targets in liberalized economies is to optimize the market structure. For a comprehensive overview of a number of waste-recycling markets in the EU, see the 2008 report of the European Commission  (DG Environment) on ‘Optimising markets for recycling’.

Several characteristics of e-waste—its bulky nature, the high cost of properly managing it, its potentially toxic constituents—distinguish electronics from ordinary trash.

Several financial mechanisms that can support WEEE recycling

Advance recovery fee (ARF), advance recycling fee, or advance disposal fee (ADF) is paid by the consumer at the point of sale when purchasing a new product and used to finance some part or all of the recycling process (OTP, 2006). The two main benefits are that a) it provides an immediate, reliable and sustainable source of funding for the entire recycling system, and b) it pays for the recycling of all returned products which eliminates the need to determine the brand ownership of returned products (OTP, 2006). In addition, the ARF is easy to grasp for consumers. A possible disadvantage to this system, more so than with the other financial mechanisms, is that it is difficult to include internet sales (OTP, 2006). Another difficulty is to enforcement to ensure compliance by all retailers (OTP, 2006). In addition, the mechanism does not encourage manufacturers to design their products with recycling in mind, and that the manufacturer has no real responsibility for recycling (OTP, 2006). Also, the system might not provide much incentive to recyclers to bring costs down (OTP, 2006).

CGeneral Tax Base Funding. The general tax base model is, compared to other approaches, relatively simple: an additional tax would be imposed at the state or national level to fund the state or national electronics recycling effort (OTP, 2006). Different methods have been applied in different Member States of the European Union (DTI, 2003). For instance, Denmark has used a local household waste tax to fund local authority collection, transport, and recycling of WEEE, while the Netherlands and Norway have used municipal taxes to finance just local authority collection (DTI, 2003). The general tax base model shifts the responsibility from specific consumers of these electronic goods and others in the product stewardship chain to all taxpayers (OTP, 2006). Therefore, this financing system has no product stewardship or shared responsibility in its design (OTP, 2006).

End-of-Life Fees. End-of-life (EOL) fees are defined as a cost paid by the end-user at the point of discard for the electronic device and is used in several States of the USA (OTP, 2006). The collection of EOL fees does not necessarily require legislation. The main advantages of a EOL fee is that it provides immediate funding for a recycling system, it pays for orphan products, and the financing costs are paid by the consumer and not the taxpayer (OTP, 2006). The main disadvantage of an EOL fee is that the consumer or end user might resort to illegal dumping to escape the fee, which is counterproductive to what the fee aims to achieve (OTP, 2006). In other words, the EOL fee discourages consumer or end user participation (OTP, 2006). Moreover, placing the cost of the recycling system at the end user can be considered unfair since the end users are are often the lowest-income consumers or charity organization (OTP, 2006). 

Deposit and Refund. The consumer makes a deposit at the time of purchase of a new product and receives a refund upon returning the used container. The refund would be less than the deposit, thus funding the system (OTP, 2006). The advantages of this financial mechanism are that it encourages the consumer to return the product (OTP, 2006). In addition, it encourages scavenging of the product. This financial mechanism is popular for products such as bottles and cans. However, it is argued that the mechanism would be less suitable for electronics. Since electronics are held for years, the deposit might be too small compared to the total purchase price to provide an incentive to return it (OTP, 2006). In addition, bottles and cans are a single material whereas electronics are not. Moreover, a deposit and refund financial mechanism requires a transaction at both the front-end and back-end, which doubles the transaction costs (OTP, 2006).  

Producer Responsibility and Cost Internalization. This financial mechanism aims to extend the responsibility of the producer for the environmental impacts of their products to the entire life cycle of the product, especially for the take-back, recycling and disposal (OTP, 2006). Therefore, the mechanim moves the responsibility for discarded products to private industry instead of local government, thus incorporating the costs of product disposal and/or recycling into the product price of new products (OTP, 2006). This mechanims differs from ARF in several ways. First, there is no visible and separate fee to the consumer. Second, there is no need for retailers to establish an infrastructure to collect and remit a fee at point of sale, which eliminates the fee collection bureaucracy (OTP, 2006). Third, this mechanism might result in fewer transactions, which reduces transaction costs. Finally, the producers or the industry third party organization might need to establish a material tracking and reporting requirement to show compliance with government legislation (OTP, 2006). Other advantages of this mechanism are that it can be designed to provide: a) an incentive to develop a competitive recycling industry; b) an incentive to design for recycling. The theory is that if companies must recycle their own products—and can devise a system to actually recover their own products—they will design them to be easier, and therefore cheaper, to recycle (OTP, 2006); c) the least cost for consumers and local governments; d) flexibility to create a variety of collection systems (OTP, 2006). Disadvantages of the mechanism are: a) for the mechanism to work optimally, producers should directly recycle their own products. However, this requires very labor intensive sorting and additional transportation costs (OTP, 2006). Moreover, the number of brands in electronics is very high (OTP, 2006). But, the introduction of Radio Frequency Identification in products might make it easier to sort brands (OTP, 2006); b) the mechanism has some difficulty treating orphan products; c) costs differentiation among producers, for instance based on market share, might be necessary. This affects competitiveness of these producers. Moreover, new producers which enter the market would have the lowest recycling costs, as they have minimal market share, raising their competetiveness (OTP, 2006); and d) consumers are not included in the mechanism, which reduces consumer education about the need to recycle. 

Clean Development Mechanism market status top

When looking at the CDM project pipeline, there are few project activities that involve some form of waste recovery or recycling. Waste related projects in the pipeline include waste-to-energy projects by means of incineration or gasification or methane capture at landfill sites. Other CDM project activities relate to the use of either biomass from virgin sources or secondary biomass waste streams, generally for the production of bio-energy. The associated methodologies of these waste management technologies/processes can be used for quantifying the GHG-impact. Standard methods or protocols for quantifying the GHG-impact of recycling projects and practices are scarcer, although they almost by no exception follow the guiding principles of a life cycle assessment (LCA).

However, no CDM projects are currently registered concerning WEEE recycling. Certain methodologies are in place to support recycling projects. However, these methodologies are not fully suitable for WEEE recycling projects as the methodologies concern other sectors. For example, the CDM methodology Recovery and recycling of materials from solid wastes AMS-III.AJ.:  Version 1 which is developed to support the recycling process of specific plastics. The methodology does indicate the possibilities for WEEE recycling under the CDM. This methodology's GHG reduction calculations are based on the difference in energy use for the production of the plastics from virgin inputs versus production from recycled material. The emissions reductions accrue to the recycling facility. Currently, no CDM projects are in the pipeline that use this methodology.

There is a small scale methodology that has been proposed and that currently awaits approval that would be suitable for WEEE recycling projects. That methodology is Emission reductions by using recycling material instead of raw material SSC-NM043. While this methodology is specifically proposed to cover more general recycling options, the methodology still needs to be approved before it can be used. 

General information about how to apply CDM methodologies for GHG accounting can be found at: http://cdm.unfccc.int/methodologies/PAmethodologies/approved.html.

References top

BAN, 2002. Exporting Harm: the High-Tech Trashing of Asia. Prepared by: the Basel Action Network (BAN) and the Sillicon Valley Toxics Coalition (SVTC). Document retrieved November 10th 2010 from: http://www.ban.org/index.html#ToOrderExportingHarmTheVideo

Basel, 2009. The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and Their Disposal. Document retrieved 10th of November 2010 from: http://www.basel.int/text/con-e-rev.doc

DTI, 2003. Study into European WEEE schemes. Prepared for the Department of Trade and Industry (DTI) by Future Energy Solutions in November 2003. Document retrieved November 10th 2010 from: http://bis.ecgroup.net/Publications/BusinessSectors/EnvironmentalRegsRoHS+WEEE.aspx

ETC/SCP, 2010. Europe as a Recycling Society - Recycling Policies for selected waste streams in EEA member countries. Prepared by: Tojo, N., and the European Topic Centre on Sustainable Consumption and Production. Document retrieved November 10th 2010 from: http://scp.eionet.europa.eu/publications

EEA, 2009. Waste without borders in the EU? Transboundary shipments of waste. European Environment Agency EEA Report No 1/2009. Document retrieved November 10th 2010 from: http://www.eea.europa.eu/publications/waste-without-borders-in-the-eu-transboundary-shipments-of-waste

Greenpeace 2008.Chemical contamination at e-waste recycling and disposal sites in Accra and Korforidua, Ghana. Greenpeace Research Laboratories, Technical Note 10/2008, August 2008. Available at: http://www.greenpeace.org/raw/content/international/press/reports/chemical-contamination-at-e-wa.pdf. 

EEA, 2003. Waste from Electrical and Electronic Equipment (WEEE) - quantities, dangerous substances, and treatment methods. Prepared by: Crowe, M., Elser, A., Gopfert, B., Mertins, L., Schmid, J., Spillner, A., & Strobel, R. European Environment Agency. Document retrieved November 10th 2010 from: http://scp.eionet.europa.eu/publications

OTP, 2006. Recycling Technology Products - An Overview of E-waste policy issues. U.S. Department of Commerce - Office of Technology Policy. Document retrieved November 10th 2010 from: http://www.epa.gov/osw/conserve/materials/ecycling/pubs.htm