Acording to the Internet!

http://www.americanplasticscouncil.org/apcorg/newsroom/articles/millenium.ht
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Who'd a thought it?

{quote from the article} The earliest plastics were invented with far more
modest goals. Created from plant-based material cellulose in the mid-1800s,
they were used as replacements for ivory in billiard balls and dental
plates. But the first completely synthetic substance didn't emerge until
1907, when chemist Leo Baekeland was cooking up chemicals in his Yonkers,
N.Y., garage, hoping to develop a substitute for shellac.