I'd also encourage you to read:*edit* where both the above links are addressed.

As for things that are toxic, take any cleaner in your house and read the label. Carbon monoxide is toxic, cigarette smoke is toxic, additives in artificial sweetners are toxic, yet every single day we are exposed to them.

From my understanding of the cell tech case, they were harvesting the algae from side canals, not the actual lake body itself. If the algae from Lake Klamath truly were toxic, then the FDA would surely shut down the companies harvesting there. But it isn't and vigorous testing eunsure the algae that is harvested is safe for human consumption.