Identifying proxy data and tracing its impacts in ecoinvent was overall difficult because different authors have implemented the same proxy approach in different ways, documentation in the datasets was incomplete, and the chemical supply chains in ecoinvent were not fully connected due to the use of aggregated black box chemical data from PlasticsEurope. These issues strongly hindered data analysis, adaptation and plausibility checks. Substituting PlasticsEurope datasets with fully documented gate-to-gate data, which is publicly available, and creating a separate proxy dataset with clear documentation that is connected in cases with data gaps if needed would increase transparency, remove inconsistencies, improve traceability and add value for all users of the ecoinvent data. This approach is the only way to make sure that upstream data improvements also show up in the downstream products, and that decarbonization progress of the chemical industry can be tracked within the ecoinvent database in a timely manner. In addition, the numerous data products that are also based on similar proxy approaches or on the ecoinvent chemical data will need to be updated as well.