I'd say if you plan on ingesting it, don't do so if the water is brown. If you plan on anointing things or using it outside of your body, however, I'd still use it in my work, if I were you! It still has all of the properties you need it for. Of course, go with your gut and do what you feel is right; if you don't feel great about using the water, go ahead and toss it. You can always make more! I would suggest, to keep that from happening again, to maybe put the rosemary and salt into an empty pouch or tea bag and tie it around the lid of the bottle you're using. It can protect the water without having to actually be in it! Hopefully this helps!