Know the code. Look on the bottom of your plastic to find the recycling symbol (a number between 1 and 7 enclosed in a triangle of arrows). The code indicates the type of plastic you are using and can give you important clues about safety. “We generally say 1, 2, 4 and 5 are considered to be the safest,” says Sonya Lunder, senior analyst at the Environmental Working Group. Try to avoid using plastics with 3 or 6, as these leach chemicals that may be harmful. Number 7 is an “other” category that includes BPA-containing plastics called polycarbonates. These plastics, which you should avoid, will have the letters PC printed underneath the 7.
From:
http://www.allmetronews.com/lifestyle/56040-plastic-container-symbols-for-food-grade-plastics.html
Thank you.
Hopefully it will not only help me, but help others as well.