Source: NZ Herald, By: Dr Michelle Dickinson Find your nearest plastic bottle or tub and turn it over. You are likely to see a number inside a triangle which corresponds to it being a recyclable product. The actual numbers run from 1-7 and describe the type of plastic that the object is made from. No 1 is PET, short for polyethylene terephthalate, and used in fizzy drinks bottles, No 5 is PP, or polypropylene, probably housing your takeaway meal. Although all plastics with these numbers - apart from No 7 - can theoretically be recycled, in fact many items such as polystyrene food trays with No 6 on the bottom must be sent to landfill because of their possible contamination with meat products.Scientists and engineers call plastics "polymers", which derives from Greek origins: "poly" means many and "mer" means parts. Plastic to us describes the way a material responds to force. If you remove the applied force and it springs back like a rubber band w...