Water enjoyed by swimmers, fishermen, jet skiers and the like can turn deadly within hours. The reason? Algae.

The North Dakota Department of Health issued an algae alert earlier this month, particularly for deadly blue-green algae. Blue-green algae can produce cyanotoxins. Water containing cyanotoxins can cause sickness, rashes, dizziness and death. Animals drinking water containing cyanotoxins can die within hours. In previous years livestock, wildlife and pets have all fallen victim to cyanotoxins in state waters.

According to the Department of Health, children are at high risk when exposed to cyanotoxins due to their small size. However, adults are also at risk for illness when exposed to cyanotoxins through such activities as wading, swimming or boating.

In their advisory, the Department of Health reminds the public that “there are no known antidotes for the cyanotoxins produced by blue-green algae.”

Algae blooms are common on many bodies of water in North Dakota, usually green algae. In recent years though there has been increasing concern about blue-green algae and the deadly cyanotoxins often associated with it. While the Department of Health has not issued any public health warnings for state waters this year due to algae outbreaks, the department is urging people to be cautious in the days and weeks ahead because “it only takes a few hot days” to cause a serious algae bloom.

“We want to make everybody aware these blooms can occur and are a health risk,” said Mike Ell, HDDoH Environmental Health Section. “I think the rainfall has lessened the risk, or at least the number of incidents of blooms so far this year.”

While rainfall can freshen lakes and reservoirs, runoff can also carry with it excess nutrients and phosphorus that can ignite algae outbreaks. Last year more than 15 bodies of water were posted with algae advisories by NDDoH. So far this summer only one serious blue-green algae outbreak has been reported in North Dakota. It is at Buffalo Gap Dam, a small reservoir west of Medora. Nevertheless, Ell reminds the public that blue-green algae can develop at anytime.

“They can occur overnight, even disappear for a short period of time and re-appear,” said Ell. “They can actually sink and you won’t see them and later on they will re-appear.”

Testing for cyanotoxins can take a few days. The Department of Health says people should avoid water that looks discolored, scummy or has a foul odor. Algae can appear as mats on the surface of water. Blue-green algae has the appearance of spilled paint. All are indications to avoid contact with the water.

Algae outbreaks are especially troubling for livestock owners. Livestock often drink from sloughs and stockdams, places that can produce the sometimes deadly form of blue-green algae quickly.

“Some of these cyanotoxins are quick acting neurotoxins and can kill livestock in a few minutes to a few hours,” said Dr. Michelle Mostrom, Veterinary Diagnostic Lab, North Dakota State University.

Ell advises anyone concerned about blue-green algae to learn more on the department’s website at ndhealth.gov. A search there will reveal considerable information about algae outbreaks. The website also includes a reporting form where people can relay information about algae outbreaks directly to the NDDoH.

Tips to avoiding cyanotoxins

— Respect advisories announced by public health authorities.

— Do not swim, water ski, or boat in areas where the water is discolored or where you see foam, scum or mats of green or blue-green algae on the water.

– If you accidentally swim in water that might have a cyanobacteria bloom, rinse off with fresh water as soon as possible.

— Do not let pets or livestock swim in or drink from areas where the water is discolored or where you see foam, scum, or mats of algae.

— If pets (especially dogs) swim in scummy water, rinse them off immediately – do not let them lick the algae (and toxins) off.

– Do not irrigate lawns or golf courses with pond water that looks scummy or smells bad.