Thank you HipShot.
UPDATE:
http://www.pnj.com/apps/pbcs.dll/article?AID=/20080619/NEWS01/80619029/1006/NEWS01
“Suspicious powder found”
JUNE 19, 2008
ARTICLE SNIPPET: “After a battery of tests, the powder was determined not to be hazardous.
It was identified as polyethylene, a substance used to make a variety of plastic items such as shopping bags.”