OPINION: Food contamination in general could be an act of terrorism.
Investigators can/do determine whether terrorism is involved.
I have not heard/read of any update at this time that indicates terrorism was involved in the pet food recall.
(http://www.recalls.gov )
http://www.news.com.au/common/imagedata/0,,5419539,00.jpg
http://osint.internet-haganah.com/archives/000923.html
(News.com.au - March 16, 2007 - "Meet The Forgotten Terrorist")
March 20, 2007
"ANOTHER TERRORIST, ANOTHER EXCUSE FOR A PITY PARTY"
If it turns out that gluten was the contaminant that is worrisome. Gluten is in A LOT of foods for human consumption.