The timber satellite has been built by researchers at Kyoto University and the logging company Sumitomo Forestry in order to test the idea of using biodegradable materials such as wood to see if they can act as environmentally friendly alternatives to the metals from which all satellites are currently constructed.
Looks like the research into upper atmosphere metallic contamination hasn’t been studied much yet, they just know it’s becoming more prevalent, but don’t know that problems that creates yet. https://www.pnas.org/doi/full/10.1073/pnas.2313374120