It doesn't look like they are particularly helpful, but it also doesn't seem like they automatically remove the possibility of life, either. This is especially

It doesn't look like they are particularly helpful, but it also doesn't seem like they automatically remove the possibility of life, either. This is especially true when considering that any Martian life would potentially be significantly different than life here. http://en.wikipedia.org/wiki/Perchlorate#Health_effects http://en.wikipedia.org/wiki/Perchlorate#Health_effects