Answer: I'm thinking you may have not posted the second half of your question, but here's some info about the 7A group in the periodic chart. To my knowledge all have molecular state that can be used as a form of antiseptic or sanitary purposes other than astatine which I'm not familiar with.
Halogens are highly reactive, and they can be harmful or lethal to biological organisms in sufficient quantities. This reactivity is due to high electronegativity and high effective nuclear charge. Halogens can gain an electron by reacting with atoms of other elements. Fluorine is one of the most reactive elements.
Explanation:
