1 July 2009
Two chemical compounds are used in the manufacture of polyethylene terephthalate (PET) bottles, diethylexyl adipate (DEHA) and di-ethylhexyl phthalate (DEHP). Neither compound is classified as cancerous nor is there evidence of any negative effects on humans.
As chemicals do not diffuse as readily in cold temperatures, reusing PET bottles by freezing water in them doesn't pose any threat. However, PET bottles are non-microwaveable plastics as there is a risk of chemicals being released that may be harmful.