Well i did some google research and couldnt really come up with any substantial evidence against the re-using of drink bottles. I'll throw up a couple of interesting links i found.
I guess the whole issue is still a little controversial and the best bet would just to be open to and aware of the
possible dangers.
http://www.grist.org/advice/ask/2004/08/02/umbra-bottles/
http://www.plasticsinfo.org/beveragebottles/APCWaterBottlesFAQs.pdf
http://www.emagazine.com/view/?1132 (good article)
This is also from an article but i thought i would paste it here as it was a good breakdown of the different types of plastics and their relevance to possible chemical leaching.
1 Polyethylene terephthalate (PET or PETE) Used to make soft drink, water, sports drink, ketchup, and salad dressing bottles, and peanut butter, pickle, jelly and jam jars.
GOOD: Not known to leach any chemicals that are suspected of causing cancer or disrupting hormones.
2 High density polyethylene (HDPE) Milk, water, and juice bottles, yogurt and margarine tubs, cereal box liners, and grocery, trash, and retail bags.
GOOD: Not known to leach any chemicals that are suspected of causing cancer or disrupting hormones.
3 Polyvinyl chloride (V or PVC) Most cling-wrapped meats, cheeses, and other foods sold in delicatessens and groceries are wrapped in PVC.
BAD: To soften into its flexible form, manufacturers add “plasticizers” during production. Traces of these chemicals can leach out of PVC when in contact with foods. According to the National Institutes of Health, di-2-ethylhexyl phthalate (DEHP), commonly found in PVC, is a suspected human carcinogen.
4 Low density polyethylene (LDPE) Some bread and frozen food bags and squeezable bottles.
OK: Not known to leach any chemicals that are suspected of causing cancer or disrupting hormones, but not as widely recycled as #1 or #2.
5 Polypropylene (PP) Some ketchup bottles and yogurt and margarine tubs.
OK: Hazardous during production, but not known to leach any chemicals that are suspected of causing cancer or disrupting hormones. Not as widely recycled as #1 and #2.
6 Polystyrene (PS) Foam insulation and also for hard applications (e.g. cups, some toys)
BAD: Benzene (material used in production) is a known human carcinogen. Butadiene and styrene (the basic building block of the plastic) are suspected carcinogens. Energy intensive and poor recycling.
7 Other (usually polycarbonate) Baby bottles, microwave ovenware, eating utensils, plastic coating for metal cans
BAD: Made with biphenyl-A, a chemical invented in the 1930s in search for synthetic estrogens. A hormone disruptor. Simulates the action of estrogen when tested in human breast cancer studies. Can leach into food as product ages.