The Recycling Symbol Numbers on the Bottom of Plastic Bottles

The type of plastic bottle in which water is usually sold is #1, and is only recommended for one time use.

If it is a #2 HDPE (high density polyethylene), or a #4 LDPE (low density polyethylene), or a #5 PP (polypropylene), your bottle should be fine.

#7 -- may leach BPA. Polycarbonate (marked as #7), usually found in baby bottles, 5-gallon water bottles and the epoxy lining in food cans can leach BPA into liquids and foods. Most plastic baby bottles and drinking cups are made with plastics containing Bisphenol A. Bisphenol A is a xenoestrogen, a known endocrine disruptor, meaning it disturbs the hormonal messaging in our bodies. Synthetic xenoestrogens are linked to breast cancer and uterine cancer in women, decreased testosterone levels in men, and are particularly devastating to babies and young children.