I don't even know where to start with this one. Apparently the mental health service kokocares.org ran a multi-day trial on 4000 users without their informed consent, in which koko's "peer supporters" used ChatGPT to craft their responses to the people they were providing with mental health support.
https://www.businessinsider.com/company-using-chatgpt-mental-health-support-ethical-issues-2023-1