Increasingly, political tensions are seeping into everyday topics. This imposition of politics can change the flow of and dynamics within conversation. In this mixed-methods study, we address the act of politicizing science on YouTube. Using comment data from educational science videos, we identify the moment of explicit politicization and how this changes the subsequent conversation. Results show that politicization becomes more likely as the thread goes on and once a thread has been politicized, it remains that way. Furthermore, after politicization the toxicity of the subsequent comments increases, “tipping” the conversation about science toward personal accusations and attacks about political identity and partisanship. Qualitative insights reveal common “pathways” to politicization, which can be used to design mitigation strategies.
