Ohio Governor John Kasich declared a state of emergency for 600,000 residents in two counties of Toledo after water samples tested positive for microcystin, a toxin that caused by an algae bloom in nearby Lake Erie.

Residents of Lucas and Wood counties were advised Saturday not to drink tap water due to the presence of the toxin caused by harmful algal blooms or HABs.

Like Us on Facebook

The Erie County Water Authority warned residents of both counties located at the western end of Lake Erie to boil their tap water before drinking it.

Paul Whittam, director of water quality services for the water authority, warned residents to use the water only to shower or wash their faces.

He advised residents not bathe their children because they might accidentally ingest the water.

Whittam couldn't say when the water would be safe to drink.

This is the first time a large city in Ohio has been forced to issue a "do not drink" order due to algal toxins in Lake Erie, said the Associated Press. An incident in 2013 affected 2,000 residents of a smaller community east of Toledo.

The west end of Lake Erie is susceptible to algae blooms because it is shallow and the current is slow. The eastern end has much deeper water with faster currents.

Microcystins are "cyanotoxins" that are very dangerous to plants, animals and humans. Their hepatotoxicity might cause serious damage to the liver and kidneys.

Among the symptoms of microcystin ingestion are diarrhea, nausea, and abnormal liver function. There is a possibility of seizures and respiratory arrest in severe cases.

Fatalities from microcystin ingestion are rare.

Scientists previously predicted this significant bloom of blue-green algae in Lake Erie. This particular algal bloom is projected to peak in early September.

Despite the warnings, the water authority said that tap water is safe, by and large.

"There's no cause for alarm here," said Whittam. "Water quality is excellent on this end of the lake."

Whittam claims there's nothing to indicate water quality in the western end has been compromised.

"Residents should not be concerned about the water quality," he said. "

The quality of water is excellent. You should have no concerns over the issues that are affecting Toledo. They are not going to be here."