Though Toledo's water ban is now lifted, residents of northwest Ohio weren't able to drink or use water over the weekend, after a toxin linked to a harmful algae bloom in Lake Erie was discovered on Friday. With global temperatures continuing to rise and modern farmers entrenched in their heavy use of fertilizers and pesticides, scientists say the problem of algae and its toxic byproducts is likely to worsen.
The toxin that caused more than 400,000 to do without tap water for two days is called microcystin. It's produced by microcystis, a blue-green algae that the NOAA says has exploded in Maumee Bay in Lake Erie's western basin. When ingested or exposed to skin, mycrocystin can cause rashes, vomiting and even liver damage.
Algae in the Great Lakes has been on the up-and-up over the last several years. Blooms had been relatively small and infrequent in decades prior, but scientists say increasing amounts of phosphorous collecting in the lakes has encouraged large growths.
A ban on phosphorous in laundry detergents in 1988 helped curb algae blooms. But bigger industrial farms using increasing amounts of phosphorous-rich fertilizers have seen growth of the green scum return. Longer hotter summers exasperate the blooms.
Notable deaths of 2014 [PHOTOS]