Plastic identification

Is it possible to use the recycling numbers (e.g., 1,2 etc.) on plastics
to identify "safe" plastics?  This would be as a guide for the public,
when you advise them to go out and purchase a box for storage or making
a microenvironment, and tell them that only certain plastics are safe,
and then they are stuck because they can't identify the plastics without
contacting manufacturers, etc.  So, would a recycle #1 (milk jugs, etc.)
identify a polyethylene, and so on? Thanks.

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                  Conservation DistList Instance 7:80
                    Distributed: Monday, May 9, 1994
                        Message Id: cdl-7-80-008
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