Northwest Ohio is in the third day of a water ban affecting more than 400,000 people. The ban was ordered after tests showed high levels of a dangerous toxin in the water supply for Toledo and surrounding areas. The toxin, microcystin, causes skin rashes and can lead to liver damage. In a briefing to reporters, Toledo Mayor Michael Collins said that while toxin levels are improving, there is no timeline for when water will be safe to drink.

Toledo Mayor Michael Collins: “But I can’t give you a time. If I could, I would. But I can’t, because I don’t have that time. And all I can tell you is everything is trending in a very positive direction.”

The high levels of the toxin microcystin are caused by blooming algae on Lake Erie. Several factors fuel algae increases, including an excess runoff of phosphorus from industrial farms that use excess fertilizer and adopt other poor practices. Climate change is also linked to algae blooms, with heavier rains and hotter temperatures causing an increased phosphorus runoff into the lake.