Have you ever wondered what those numbers on the bottom of your plastic soda bottle mean? These little numbers with the arrows around them are found on most plastics product ranging from food storage containers to laundry detergent bottles, shopping bags to household appliances.
The Society of the Plastics Industry, Inc. (SPI) introduced this resin identification coding system in 1988 in an effort to help recycling centers in the US effectively separate the different types of plastics for recycling. Since then, this system has been adopted and used worldwide.
Research has shown that the material numbered 1 to 6 – PET, HDPE, PVC, LDPE, PP, PS – are the 6 most commonly used plastics material in the world. These are material used to produce many of the plastics products we see around us. Number 7 represents all other types of plastics material.
Contrary to many misconceptions about this symbol, the number does not represent:
- - How many times the product has been recycled.
- - Quality rating of a product – 1 is good, 7 is bad – or vice versa.
- - Which number is safe for storing food and which is not.
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