Those numbers inside the triangle do tell you what type of plastic is used. The codes are for recycling, but I don't know how that translates to safety.
You might want to check out this link...
Not necessarily. They are numbered to tell you what kind of plastic is used in the container. To be safe, stop using plastic for food and water all together. If you want to get a great reusable glass water bottle check out http://livinglavidaverde.net/store.aspx .Is it normal to keep emotions bottled up?