> The process of chlorinating water was first done illegally.

I tried to find a source on this but it doesn't seem to be true? The first chapter of this book describes the history of chlorination: https://upload.wikimedia.org/wikipedia/commons/f/fd/Chlorina... (which is a source Wikipedia cites) and it doesn't appear to mention anything about illegally chlorinating water. After looking in that book I asked ChatGPT to find a source for the claim, and it reported the claim was false. Chlorination was initially controversial but I can't find anything claiming it was illegal?