[Dosa26]

but there is also the possibility of introducing a species of parasite or non-indigenous organism to cause ecological havoc

I would take this threat seriously if a genetically modified freshwater red/black tide turned up, ironically the zebra mussuls (non-indigenous rumored to be spawned from european vessels dumping bilge) are cleaning up the suspended particulates and concentrating the "life" of the lake on the bottom.

[Smokin' Joe]

It just dawned on me that instead of engineering human disease bioagents, other forms which attaack other species may be effective in warfare as well. Inducing crop failures, fish kills, sickness in livestock, etc. could be equally effective, and could be developed without the need for the safeguards that human bioagents would require... Starvation is one of the original weapons of mass destruction.