Canwest News Service: Sprinkling iron in the sea has long been touted as a fix for global warming, but researchers are now warning such geoengineering could nourish toxic algae. Tests conducted by a Canadian-U.S. team show that enriching water with iron favours the growth of Pseudo-nitzschia, an algae that pumps out a potent neurotoxin. It can be lethal to seabirds and marine mammals, and is linked with amnesic shellfish poisoning in humans, which can be deadly. The findings “raise serious concerns” …