1. I just posted on a different thread that the remake needs to have a DIFFERENT weakness since its too easy to exploit and thus not that interesting a weakness.
2. In the tv series based on the movie that DID happen, some bullies put sea water in a squirt gun and squirted an alien girl in the face. She was in the hospital having the chemical burns treated and they were mostly on her cheek and the doctor told her she was very lucky none of it got in her eyes because that would have permanently blinded her.
3. Salt water might not do it it might have to specifically be OCEAN WATER, there are way more chemicals in it than just salt. That is not so easy to get especially if you live inland.