Aluminum cookware is generally safe as long as you are not cooking acid or alkaline foods. Aluminum does form a layer of aluminum oxide on its surface and that layer reduces contact with pot contents. Hard anodized aluminum is better. There really is no food grade aluminum, just different alloys. The softer alloys will be more common in cookware, since they are easier to form. Most aluminum food containers that might be affected by the food inside them have a thin plastic coating on the inside. The plastic coating will burn off when heated, so they are not a good choice for cooking, but may be OK for drinking. You will have to decide whether the plastic coating is better or worse than no coating. Since most of what I do in camp cooking is to boil water, I don't worry about it.