Deadly edible?

We have both green and bronze perilla (beefsteak plant) as an invasive here, and I read that it is used in cooking, but also that parts of the plant are poisonous if ingested! Does anyone know which parts those are? Yikes!

Here's an old thread about them: http://davesgarden.com/forums/t/619138/

It's toxic to cattle and horses and maybe deer, but not people. In terms of the supposedly poisonous part of the plant, I think someone gave you a kind of garbled version of the fact that cows poisoned by the plant were found to have the seeds in their rumen. However, the seeds are used as a spice in the East. Some people who work with it all the time, like farmworkers, can get dermatitis from it.

Here's a nice page of info. I have found Plants For a Future to be a great source for the edibility of various plants:

http://pfaf.org/database/plants.php?Perilla+frutescens

Thanks! Very interesting site!