Monday, August 18, 2014

Microcystins – Blue Green Algae- Cyanobacteria Your Drinking Water

Microcystins – Blue Green Algae- Cyanobacteria
Your Drinking Water

The first step in understanding this situation is it is important that you understand the source of your drinking water.  Is the source a surface water reservoir, stream, river, or groundwater source and if you are part of a municipal or regulated water supply or if you are a private water supply system.   The second step is to review available water testing information on the quality of the water.  If you have not gotten any data in the mail and you do not get a water bill, it is likely that you are on a private system and need to get your WATER Tested Yourself.   If you get an annual report, you would want to look at issues related to general quality and the source of your water.  If the report says that the source is a lake or reservoir and there is a Water Treatment Plant that filters the water, it is likely your source could be influence by Microcystins and Blue-green Algae.

So what happened in Ohio and what is microcystin?
In Toledo, Ohio -Toledo's Collins Park Water Treatment Plant found two sample readings for microcystin in excess of the one-microgram-per-liter (1 ug/L or 1 ppb or 0.001 mg/L).  First – they did not mention if this was in the raw or finished (treated) water.  It would make sense is was the level in the finished or treated drinking water.

There is no federal drinking water standard for microcystin, but there is a WHO (World Health Organization) has a provisional standard for Microcystin-LR of 1 ug/L.  Microcystins are not regulated by USEPA in drinking water, but are unregulated microbial drinking water contaminants listed on the USEPA's Contaminant Candidate Lists (CCLs) 1 and 2 as cyanobacteria and their toxins.  Specific varants, Anatoxin-A, Microcystin-LR and Cylindrospermopsin, are on the USEPA's Contaminant Candidate Lists 3- CCL3.   Minnesota analysis of acute response suggests a guidance limit of 0.04 ug/L, but the method detection limit for the available method is 0.15 mg/L.

What are blue green algae (cyanobacteria)?   (Yes we are talking about POND SCUM!)

Blue green algae lives in a wide range of environments including freshwater, saltwater, brine, soil and even in very brackish water.  They are among some of the oldest “organisms” on the planet and probably responsible for the fact we actually have oxygen. They can live in freshwater, salt water, or in mixed “brackish” water.  They are called blue-green algae, but they come in a wide range of colors including red, brown, orange, and green (Strange – They do not come in BLUE).  These blue green algae can actually be many colors including green, red, orange, or brown.   Because these organisms have characteristics similar to bacteria they are called or known as “cyanobacteria.” Cyanobacteria are one of the oldest microorganisms on Earth, predating predators, 3.5 billion years ago.

What causes these organisms to form “blooms”?
Well for some the answer is Climate Change, but for them the answer to most things is climate change.   The real reason why we have blue green algae blooms is because these organisms have an advantage.   When they do not have enough nitrogen to grow – they can fix the nitrogen directly from the atmosphere.  Just think – you would have an advantage over others if you could PRINT MONEY.  For these organism, this happens when there is so much phosphate in the water the growth rate of the organism is no longer limited by the phosphate, but limited by nitrogen.  When this occurs, these organisms have the advantage and then out-grow and shade out all the other algae.  The second advantage they are big and small fish and zooplankton do not like to eat or can not eat. 

What causes some blooms to be toxic?
Only some blue-green algae produce microcystin toxins.  Why?  You will not like this answer, but we do not know.  My guess is it is a defense mechanism to prevent predation by zooplankton or it could be just part of the metabolite process they developed. There are thousands of blue green algae species and many more are still being discovered. Most do not produce toxins that are harmful to people or animals. However, some types of blue green algae produce toxins within their cells which are released when the cells die off or are ruptured. It is not clear why blue green algae make these toxins.

A microcystin is?
A toxin produced by bacteria of the genus microcystis (
planktothrix cyanobacteria (i.e., some filamentous blue green algae), a type of blue-green algae, or cyanobacteria. Only certain species of blue-green algae form toxins, for reasons that aren't fully understood. Microcystins are toxic peptides, i.e., peptides are short chains of amino acids linked together via peptide bonds. These peptides are produced in large quantities during blooms.  Microcystins typically persist even after the collapse of the algal blooms.  Microcystin can produce hives or blisters from direct contact with the skin. Swallowing it can cause headaches, fever, nausea, vomiting and diarrhea. Large-scale ingestion can damage the liver.

What environment factors lead to formation?
Microystin is associated with blooms of Cyanobacterial, i.e., blue-green algae.  The primary environmental factors that lead to this condition high levels of phosphorous (source direct discharges, non-point sources, and internal cycling from the sediments), growth limiting nutrient is nitrogen not phosphorous, temperatures in the 5 to 30 C and related to the condition within the surface water source, such as a lake that recent was “turned over” and is not a complete mix system.   Is this caused by climate change – the science is not in yet – My Scientific Opinion Based on Available Data is NO, but I am open to Facts!
Microcystin toxins are nonvolatile, hydrophilic (i.e., have an affinity for water- “Makes Sense”, and stable in sunlight, and stable over a wide temperature and pH range. Factors affecting toxin production are light and temperature, with optimum temperatures from cyanobacteria ranging 20 to 25 C- as the algae becomes more productive the levels of microcystin increase.  Elevated levels may persist for up to 2 months following the decline of the algal populations.

YOU may have a problem with your lake or reservoir, if:

Based on these studies - Current recommendation are as follows:
1. Monitor you lake quality, parameters such as pH, conductivity, phosphate, secchi depth, and alkalinity.
2. Monitor the vertical profile of the lake or reservoir and understand how it changes overtime. 
3. Avoid contact with blue-green algal blooms.
4. The greatest risk may be when the water transparency or secchi depth is low (< 0.5 m), pH > 9.0, or when distinct surface scums are visible.
5. If you have the budget, hire a professional to assist with conducting a lake and watershed assessment to understand the sources and sinks for nutrients and the food-web for the system.
6. Test for chlorophyll a, conduct phytoplankton and zooplankton counts, and test the water for mirocystin.


Resources on Lake Monitoring
Published Books, Guides, and Monitoring Devices
Online Web-Portal - Information on Watersheds
Role of Phosphate

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