Developing Ecological Life Cycle Impact Assessment Characterization Factors for CdTe

A variety of regulated metals are currently being used in three generations of photovoltaic technologies. Understanding the potential life cycle environmental impacts from use of these materials requires data on their physico-chemical and (eco)toxicological properties. For the thin film semiconductor CdTe, the documentation of physical, chemical, and toxicological properties in conjunction with the consensus toxicity model USEtox can be used to evaluate the potential impact of CdTe emissions on ecosystems. The freshwater ecotoxicity characterization factors (CF) are in a low range compared to metal ions in the USEtox database, due primarily to lower ecotoxicity effects on freshwater ecosystems measured for three trophic levels (algae, crustaceans, fish). Potential ecotoxic impacts of CdTe are approximately 3 orders of magnitude lower than Cd. Given the uncertainty of a factor 10-100 for freshwater ecotoxicity characterization factors, this difference is superior to the uncertainty range.