I found a really good, short, but informative article about items that many people keep on them, in their purse, lunch bag or gym bag.
The article can be found here: http://healthypets.mercola.com/sites/healthypets/archive/2012/01/26/pet-poisons-in-owners-bags.aspx
Give it a read, some of these items may surprise you and change the way you store these things.