Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan.
Sci Total Environ. 2012 Nov 1;438:49-58. doi: 10.1016/j.scitotenv.2012.08.017. Epub 2012 Sep 7.
Lead-free electronics has been extensively studied, whereas their adoption by society and their impact on material substitution and environmental emissions are not well understood. Through a material flow analysis (MFA), this paper explores the life cycle flows for solder-containing metals in Japan, which leads the world in the shift to lead-free solders in electronics. The results indicate that the shift has been progressing rapidly for a decade, and that substitutes for lead in solders, which include silver and copper, are still in the early life cycle stages. The results also show, however, that such substitution slows down during the late life cycle stages owing to long electronic product lifespans. This deceleration of material substitution in the solder life cycle may not only preclude a reduction in lead emissions to air but also accelerate an increase in silver emissions to air and water. As an effective measure against ongoing lead emissions, our scenario analysis suggests an aggressive recycling program for printed circuit boards that utilizes an existing recycling scheme.
无铅电子学已经得到了广泛的研究，但其在社会中的采用及其对材料替代和环境排放的影响还没有得到很好的理解。本文通过物质流分析（MFA），探讨了日本含铅金属在电子领域向无铅焊料转变过程中的生命周期流动情况。研究结果表明，这种转变在过去十年中一直在迅速推进，而替代焊料中的铅的银和铜等材料仍处于生命周期的早期阶段。然而，研究结果还表明，由于电子产品的使用寿命较长，在生命周期的后期阶段，这种替代速度会放缓。这种焊料生命周期中材料替代的减速不仅可能不会减少铅向空气的排放，反而会加速银向空气和水的排放。作为应对持续铅排放的有效措施，我们的情景分析建议实施一项积极的印刷电路板回收计划，该计划利用现有的回收方案。
