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2019 Cyanobacteria Lab Test Results

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Algae are a diverse group of aquatic organisms that have the ability to turn sunlight into chemical energy and food through a process called photosynthesis. Algae thrive in freshwater environments, and can range from invisible single-celled microbes floating in water to the larger - and more familiar - kelp and seaweeds. Common green algae is multicellular, has chloroplasts that aid in photosynthesis, and ranges in size from 300 to 1,000 micrometers.

According to the Environmental Protection Agency (EPA), harmful algae blooms can have major impacts on everyday life, such as:

  • Producing dangerous toxins that can sicken or kill people and animals
  • Creating dead zones in the water
  • Increasing drinking water treatment costs
  • Hurting industries that depend on clean water

Yet in spite of their unpleasant appearance, foul smell, and potential to harm the health of humans, animals and fish, the National Ocean Service reminds us that "not all algae blooms are harmful. Most blooms, in fact, are beneficial because the tiny plants are food for animals in the ocean. In fact, they are the major source of energy that fuels the ocean food web."

Cyanobacteria (Blue-Green Algae)

Cyanobacteria is another term associated with algae blooms. However, cyanobacteria is not a true algae at all. Since cyanobacteria are photosynthetic and aquatic, they are often called blue-green algae. Cyanobacteria cells range in size from 0.5 to 60 micrometers but when allowed to flourish, can produce impressive mat-like colonies in fresh and marine waters that look identical to true algae blooms. Although cyanobacteria cells lack flagella to freely swim about, they are able to change their depth in the water. Cyanobacteria-contaminated water does not always exhibit any taste or odor problems. Over 46 species of cyanobacteria are capable of producing toxins.

Algae Blooms

Algae blooms are smelly and potentially harmful to your health, algae blooms are overgrowths of algae or cyanobacteria in water. Algae blooms that contain toxins and can be harmful to human and animal health are more specifically called “harmful algae blooms”.

Algae blooms can be made of algae or cyanobacteria. It is important to understand the differences and similarities of the two.

Cyanobacterial Toxins

Cyanotoxins are produced by cyanobacteria (also known as blue-green algae), and are often released upon cell death or when the cell membrane ruptures. Some cyanobacteria can release some of their toxins without cell death.

Types of cyanotoxins include:

  • Neurotoxins (nerves) - can cause paralysis of skeletal, respiratory muscles
  • Dermatotoxins (skin) - can produce rashes, skin reactions
  • Endotoxins (gastrointestinal epithelium) - can produce fever, induce immune response

Microcystins are hepatotoxins that are a potential carcinogen of the liver and kidneys

There is no way to tell if an algal bloom is toxic by looking at it. To protect yourself and your pets, it is advisable to:

  • Check for beach warnings posted near the water or online
  • Avoid water that might be contaminated - look for the presence of mats/crusts, foul odor or color, or dead fish that have washed ashore
  • Promptly seek medical care if you suspect you or your pet have been exposed to a harmful algal bloom

Remember, boiling water does not remove algal toxins - it can actually concentrate the amount of toxin in the water. Also, toxins may remain in water for some time after the bloom has gone away.

Black Berkey® Water Filter Microcystin-LR and Microcystis Test Results

Drink with confidence - third-party lab tests show that Black Berkey® Water Filters are extremely effective at removing microcystin toxins and microcystis algae.

Microcystin LR Toxin Filtration

Microcystin-LR is the most common microcystin variant found in bloom samples.47 Black Berkey® Water Filters remove microcystin-LR to greater than 99.7% (>log 2.5), reaching the test’s reporting limit with no toxin detected.

Microcystis Algae Filtration

Planktonic cyanobacteria can produce harmful cyanotoxins. Microcystis is the most common bloom-forming genus, and is almost always toxic. Black Berkey® Water Filters remove 99.97% of microcystis algae (log 3.5).

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