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Sustainable Use and Restrictions of Materials in the Electronics Industry

: Deubzer, O.; Griese, H.; Reichl, H.; Madsen, J.; Wel, H. van der

Reichl, H.; Griese, H.; Pötter, H. ; Fraunhofer-Institut für Zuverlässigkeit und Mikrointegration -IZM-, Berlin:
Driving forces for future electronics : Joint International Congress and Exhibition Electronics Goes Green 2004+; September 6 - 8, 2004, Berlin, Germany. Proceedings
Stuttgart: Fraunhofer IRB Verlag, 2004
ISBN: 3-8167-6624-2
ISBN: 978-3-8167-6624-7
Joint International Congress and Exhibition "Electronics goes green 2004+" <2, 2004, Berlin>
Fraunhofer IZM ()

Sustainability requires "meeting the needs of the current generations without compromising the ability of future generations to meet their needs". This definition challenges the use of non-renewable resources, because each consumption of such resources affects the availability of these resources for future generations. The sustainability concept thus requires a broader base for decisions about use or bans of material, especially with regard to hazardous materials. The use of hazardous materials can cause harms to organisms, while bans of hazardous materials increase the pressure on the resources of the substitutes and affect the costs for industry. It is not contentious that life needs to be protected from impacts of hazardous materials. However, another question is whether it is fair to consume the harmless non-renewable resources and leave the toxic materials to the coming generations. A new concept for the use and substitution of materials in electronics was therefore developed to facilitate a more sustainable development. The ban of lead in electronics is used as a testing field for the concept.

The first step is to differentiate between the toxic potential of a substance and the actual risk of toxic impacts from a potentially toxic substance. The potential toxicity is an intrinsic material property which only depends on the chemical structure of a material. The toxic potential of a substance depends on the concrete application of the material and the life cycle of this application. Thus, life cycle management can influence the risk that is linked to the use of hazardous materials in certain products. The end of life was identified as a hot spot. The recycling infrastructure - collection, mechanical separation, recovery of metals in smelters - was therefore investigated to assess average recovery rates for the metals from printed wiring boards (PWB). The assessment was limited to Europe, as outside Europe data are hardly accessible. The recyclers conducting the mechanical separation and the smelters enable medium to high recovery rates for tin, lead and for noble and platinum group metals (PGM). The bottleneck is the collection and actual recycling rate of PWB. The WEEE with its collection and recycling rates, however, might improve the situation. Another unknown effect is the export of such materials outside the European Union, increasingly to China. There is no evidence on what happens to these materials there.

An output-controlled model was the base for the calculation of the toxicity as well as for the energy consumption. It was assumed, that all metals, which were not recycled at the end of life of PWBs and thus left the technosphere, have to be replenished from virgin resources. The output from the technosphere into the environment therefore directly determines the necessary input and the environmental burdens from mining from the different metals. The toxic risk from lead and its substitutes is strongly linked to the overall recovery rates. Within the technosphere, measures of occupational safety and product safety rules almost eliminate the risk in manufacturing and in the use phase of electronic products. The control of materials becomes difficult once they leave the technosphere and e. g. go to a landfill site. The lead substitutes pose a much lower toxic risk compared to lead. However, the linkage of different metal resource in ores - silver, e. g., is mined together with lead - could not yet be taken into account so far.

Consumption of non-renewable materials deteriorates the quality of resources. For a sustainable consumption of non-renewable resources like metals in electronics industry, the net soldering material consumption should decrease at least as much to compensate the declining concentration of these metals in the ores. In electronics, miniaturization and integration on one hand reduce the current solder consumption of about 90,000 t/a, on the other hand facilitate ever smaller and ubiquitous products that are difficult to collect and recycle after use. At the same time, market growth increases solder consumption. Different scenarios for the technical development as well as for the market growth for electronics products show whether and under which conditions technical progress can outweigh market growth and reduce the solder and resource consumption as well as the toxic risk from the use of different soldering materials with lead as the reference.

The final result of the assessment is not yet available. Beyond toxicity and resource consumption, energy consumption, economic effects and possibly more aspects need to be identified and integrated to allow appropriate decisions about sustainable use of materials in electronics.