Algae Blooms

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Understanding Algae Blooms and Impacts on Health

Algae

Algae are large photosynthetic organisms and are normal habitants of large bodies of water like a lake. Algae are very important to both freshwater and marine environments and most species are harmless under normal circumstances. Cyanobacteria also known as “blue green algae” are actually bacteria and not a form of Algae. Algae and Cyanobacteria have very similar characteristics with the difference that certain Cyanobacteria toxins can be harmful for the environment, animals and human health.

Algae Blooms

Algae blooms occur when the algae grow at rapid speeds than normal causing dense accumulations in the water. Algae blooms are normal occurrences in bodies of water. They can become harmful when there is excessive growth. As the cyanobacteria dies off, harmful toxins can be produced known as cyanotoxins Concerns regarding blue-green algae have been on the rise throughout the Country.

What causes harmful algae blooms?

Conditions for algae blooms are ideal when there is an oversupply of nutrients in a lake, such as phosphorus and nitrogen, high temperatures, low oxygen levels in the water, little water movement, and low water levels as we’ve experienced with the current drought, create the ideal conditions for algae blooms and can lead to new, larger and prolonged blooms.

What are the effects of harmful algae blooms in humans?

Human exposure to cyanobacteria and cyanotoxins generally occurs through recreational contact (ingestion, inhalation, dermal contact) and ingestion of drinking water. The acute effects of contact recreational exposure from activities like swimming, jet skiing, etc., can result in a wide range of symptoms in humans including skin and eye irritation, fever, headaches, muscle and joint pain, blisters, stomach cramps, diarrhea, vomiting, mouth ulcers and allergic reactions. Effects can occur within minutes to days after exposure. In severe cases, seizures, liver failure, respiratory arrest, and (rarely) death may occur.

What are the effects of harmful algae blooms in pets?

Cyanobacteria can be poisonous to cats, dogs, horses, cows and birds. The level of toxicity can be generally moderate to severe. Some of the symptoms to watch for are vomiting, diarrhea, seizures, coma, shock, difficulty breathing and it can cause death in animals. For more information please visit the pet poison hotline.

How do you treat people that have been exposed to cyanotoxins?

In the event that you do come into contact with water that is known to be contaminated with cyanotoxins, the Centers for Disease Control (CDC) recommends that you rinse off with clean, fresh water as soon as possible. Remove yourself from the source of exposure. Seek medical treatment right away if you think you or someone you know might have been exposed to cyanobacterial toxins, especially when any of the symptoms mentioned above are recognized. For more information, please visit the CDC's webpage on Harmful Algal Blooms (HABs).

How can toxins from cyanobacteria be detected?

Detecting the presence of toxins from cyanobacteria is not as simple as you might think. Simply observing the algae bloom is not enough to know whether it is toxic or not. Collection of water samples and appropriate lab analysis are required to detect the presence of cyanobacteria. 

What should you do to stay protected?

The Centers for Disease Control (CDC) recommends the following:

  • Avoiding swimming, water skiing, or boating in areas where the water is discolored or where you see foam, scum, or mats of algae on the water.
  • Don't 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 on the water. If pets (especially dogs) swim in scummy water, rinse them off immediately—do not let them lick the algae (and toxins) off their fur.

Be on the lookout for signs or communications

There are three levels to determine how harmful the water can be.

Caution:

  • Do not swim or wade near algae or scum
  • Keep children away from algae in the water or on the shore.
  • Do not drink this water or use it for cooking.
  • Do not let pets go into water or drink the water or eat scum on the shoreline.
  • For fish caught here, throw away guts and clean fillets with water before cooking.

Warning:

  • No swimming
  • Stay away from scum, and cloudy or discolored water
  • Do not use these waters for drinking or cooking. Boiling or filtering will not make the water safe.
  • Do not let pets go into water or drink the water or go near the scum.
  • For fish caught here, throw away guts and clean fillets with water before cooking.

Danger:

  • Stay out of the water until further notice. Do not touch scum in the water or on shore.
  • Do not let pets go into water or drink the water or go near the scum.
  • Do not eat fish from these waters
  • Do not use these waters for drinking or cooking. Boiling or filtering will not make the water safe.

What is the City doing for the Lake? 

In July 2016, Lake Elsinore suffered a severe algae bloom. On July 28, 2016, in order to ensure utmost level of public safety, the City of Lake Elsinore closed the lake upon the detection of toxins from cyanobacteria, or blue-green algae. The lake reopened to boating and fishing on August 4, but bodily contact remained discouraged. The City is currently sampling and monitoring the lake weekly to ensure the health and safety of Lake Elsinore. Updates will be posted as they become available.  

Additional Resources Regarding Cyanobacteria 

Centers for Disease Control & Prevention - Harmful Algae Blooms 

US Environmental Protection Agency - Cyanobacteria/Cyanotoxins 

California Cyanobacteria and Harmful Algal Bloom (CCHAB) Network