@Peterm1000 Your quote was also from a page with an agenda, a company selling non-bleach cleaning products.
Note the quote on my post, that was also from the Wiki page for bleach. Any chemical that is used to kill bacteria etc is going to have toxic properties, otherwise it wouldn't do it's job. Bleach is indeed hazardous, but no more so than most other cleaning products and the fact that it is quite literally advertised on TV to pour down your toilet/sink should tell you that it is a pretty safe product to use.
Any product designed to kill moss/algae is also going to be toxic to other plants so you need to take care. I have had no problem using it myself, I apply it only to the area I need it and I don't rinse it, there is no need, as I said it will quickly turn into salty water and will evaporate, the minute amount of salt remaining will not harm plants later on.