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Mercury

Mercury is used in printed circuit boards, batteries, switches and printed wiring

boards. While the percentage found in the average PC is only 0.002%, 17 based on the

total number of disposed PCs estimated in Canada in 2000, this represents 0.5 tons of

mercury. Mercury is also found in the fluorescent lamps that were previously used to

backlight laptop computer screens, but have now been replaced with xenon.

Based on the prediction that 47,821 tons of PCs and monitors will be disposed in

2005 and assuming that the average composition of this equipment will not change

significantly by that year, 1.1 tons of mercury will be disposed with this stream in

2005.

Brominated Flame Retardants

Brominated flame retardants are used to reduce the flammability of plastics in

electronic products. They are most typically used in circuit boards, connectors, plastic

covers and cables 18. There are many types of BFRs (more than 60), some of which are

more toxic than others. The European Union Waste Electrical and Electronic Equipment

(WEEE) Directive has chosen to focus its efforts on the two classes of BFRs that pose

the highest cause for concern, that is, polybrominated biphenyls (PBB) and

polybrominated diphenyl ethers (PBDE). These are the compounds that are most likely

to form dioxins and furans during the incineration process. When these compounds are

burned, brominated materials are converted into polybrominated dibenzo furans (PBDF)

and polybrominated dibenzo dioxins (PBDD) and can be released into the atmosphere.19

Therefore, when plastics containing BFRs, in particular PBB and PBDE, are

extruded during the recycling process or when they are incinerated for disposal,

hazardous compounds may be released into the environment.

Polyvinyl Chloride Plastic (PVC)

Although most computer moldings are now made using ABS plastic, PVC has

been widely used in computer cabling and housings. There is a risk that dioxins and

furans will be formed when PVC is incinerated. In addition, PVC is a difficult plastic to

recycle if mixed with styrenics and contaminates other plastics (e.g., PET) in the

recycling process.

5.0 IT Equipment Design Changes to Reduce Toxicity and Facilitate Recycling

Many manufactures are attempting to eliminate substances of concern from their

products, including, lead, arsenic, brominated flame retardants, cadmium, hexavalent

chromium, mercury and PVC. Examples are provided below.

Hewlett-Packard’s Office Jet 500 multi-purpose printer uses a metal chassis and

power supply enclosure to eliminate the need for flame retardants and light emitting

diodes (LED’s) instead of a mercury lamp for the scanner, and eliminates the need for

batteries by using flash memory technology.

The primary plastic resin used in Intel’s PCs and servers (ABS and

polycarbonate) does not use flame retardants that contain PBBs or PBDEs.

None of their products contain asbestos, or include lead or cadmium as plastic

additives. 20

Philips Consumer Electronics evaluate all of its products against their list of

banned substances (asbestos, cadmium, mercury, CFC/HCFC, PCP, PCB, PCT,

PBB/PBBE) before their introduction. 21

Motorola conducts research with their suppliers of printed wiring board laminates,

plastics, and electronic components to replace lead and BFRs. 22

Panasonic has identified 37 substances of concern in their manufacturing

process with 13 targeted for elimination and the remaining 24 for reduction. 23

Sony Corporation is developing a non-lead based solder for some products and

seeks to eliminate dioxin forming compounds through design guidelines. 24

Toshiba has introduced the Satellite 2520 notebook with a halogen-free

motherboard and plans to switch over to halogen-free boards for the entire PC

product range by the end of 2001. 25

Digital’s (now Compaq) Corporate Regulated Material Specification includes the

banning of PBBs, PBBOs and PBBEs. Numerous other halogenated compounds

are listed in this specification including the 25 halogenated dioxins and furans,

which are restricted by the German Dioxin Ordinance.

As a part of Sony’s Green Management 2002 Plan, they will eliminate the use of

halogenated flame retardants in all European models by 2001 and in all models

by 2002.

Many manufacturers are improving the recyclability of their products by

incorporating recyclable materials into products, by making their products easier to

dismantle and by marking the various materials contained in the equipment, for example:

Plastic components of Apple products that are greater than 100 grams are made

from the same type of plastic material;

Apple designs its product with latches, snap-in connections, and single screw

types requiring no specialized tools;

Hewlett Packard designs many of its products so that they are easier to take

apart; many components simply snap apart, making it easier to separate metal

from the plastic;

IBM’s DfE (Design for the Environment) guidelines encourage the use of snap fits

instead of fasteners, and where fasteners are used, they use a minimum number of

standard sizes that do not require special tools when dismantling, and Intel’s product

design checklist encourages ease of disassembly and appropriate materials choice.

6.0 Future Trends in IT Technology

The IT

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