Polycarbonate has been commonly used to make the sturdy reusable water bottles that many of us use. Polycarbonate is one of the plastics classed as 'other' in the recycling scheme. It has a recycling code of 7, but not all bottles stamped with a 7 are made from polycarbonate.
http://www.abc.net.au/health/talkinghealth/factbuster/stories/2010/10/27/3048695.htm
Plastic #7: Other. Last but certainly not least, we have the nastiest one of all, Plastic #7. It’s a kind of catch-all designation that describes packages made of a resin other than the six standard types. It’s also used to describe plastics made from any combination of the standard six plus other resin types.
http://io9.gizmodo.com/how-to-recognize-the-plastics-that-are-hazardous-to-you-461587850
These plastics are found in bags for dry cleaning, newspapers, bread, frozen foods, fresh produce, and household garbage. They’re used in shrink wrap, coatings for paper milk cartons and hot and cold beverage cups. LDPE is used to make container lids, toys, and squeezable bottles (like honey and mustard).
http://io9.gizmodo.com/how-to-recognize-the-plastics-that-are-hazardous-to-you-461587850
PET is not one of the plastics that one would think has a propensity to cause a problem, says Moore. Moore agrees with the US FDA, which says that PET bottles are safe for use and reuse so long as they are washed properly with detergent and water to remove bacteria.
http://www.abc.net.au/health/talkinghealth/factbuster/stories/2010/10/27/3048695.htm
If you’ve been concerned, here is a handy chart that identifies the good, bad, and OK plastics and where they are found. Find out here: 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)
http://www.care2.com/greenliving/which-plastics-are-safe.html
Plastic #1: Polyethylene Terephthalate (PET) These plastics are typically used to hold soft drinks, water, juice, sports drinks, beer, mouthwash, ketchup, and salad dressing. They’re also used as containers for peanut butter, jelly, jam, and pickles.
http://io9.gizmodo.com/how-to-recognize-the-plastics-that-are-hazardous-to-you-461587850
This versatile plastic can be rigid or flexible, and it’s commonly used in the production of blister packs and clamshells (for storing pills, for example). It’s used to make bags for bedding, shrink wrap, deli and meat wrap, and tamper resistant lids. And it’s the first of the bad ones.
http://io9.gizmodo.com/how-to-recognize-the-plastics-that-are-hazardous-to-you-461587850
One plastic that can be undoubtedly dangerous for making water bottles is polyvinyl chloride (PVC), which has a recycling code of 3. PVC often has phthalates added to make it flexible — though you can't tell this by looking at the recycling code. Thankfully, PVC is not often used to make water bottles.
http://www.abc.net.au/health/talkinghealth/factbuster/stories/2010/10/27/3048695.htm
If you’ve been concerned, here is a handy chart that identifies the good, bad, and OK plastics and where they are found. Used to make soft drink, water, sports drink, ketchup, and salad dressing bottles, and peanut butter, pickle, jelly and jam jars.
http://www.care2.com/greenliving/which-plastics-are-safe.html
The 2001 study found traces of a phthalate — a potentially harmful 'plasticiser' used to make some plastics more flexible — in water from PET bottles, but the research hadn't been verified. Moore says PET has never contained phthalates and the public's association between the two could be based on the plastic's name.
http://www.abc.net.au/health/talkinghealth/factbuster/stories/2010/10/27/3048695.htm
what plastics are safe to drink from
Polyethylene terephthalate is a plastic safe to drink from. Polyethylene Terephthalate  are safe to drink from.