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Water Treatment Issues:

Acid Water

Algae, cyanotoxins

Alkalinity

Alum (Aluminum Sulfate)

Aluminum

Ammonia

Arsenic

Asbestos

Bacteria

Barium

Benzene

Bicarbonate Alkalinity

Boron (Borate, Boric Acid)

Brackish Water

Bromine

Bromate

Cadmium

Calcium

Carbon Dioxide

Carbon Tetrachloride

Chloramines

Chloride

Chlorine

Chromium

Color

Copper

Corrosion

Cryptosporidium

Cyanide

Dichloroethylene

Endocrine Disruptors

Fluoride

Giardia Lambia

Hardness

Heterotrophic Bacteria (HPC)

Hydrogen Sulfide

Iodine

Iron

Iron Bacteria

Lead

Magnesium

Manganese

Mercury

Methane

MTBE

Napthalene

Nickel

Nitrates and Nitrites

NMDA (N-Nitrosodimethylanime)

Norovirus

Odor

Organics

Perchloroethylene (PCE)

Perchlorate

Pesticides

pH

Pharmaceuticals

Radon

Radium

Selenium

Silica

Silver

Strontium

Sulfate

TDS (Total Dissolved Solids)

Trichlorethylene (TCE)

Tritium

Uranium

Vanadium

Vinyl Chloride

VOC


Algae, cyanotoxins

Algae and cyanotoxins
 

Blue-green algae, or cyanobacteria, and other algae include a number of species of microscopic aquatic organisms that perform photosynthesis to produce energy and oxygen. They produced Earth’s earliest fossils.

Often identified as "pond scum," some are important food sources but others put out toxic compounds called cyanotoxins that are harmful to humans and other animals.

Green scum produced by and containing cyanobacteria.

Cyanobacteria also produce organisms that give water a musty odor. Reports of algae-caused unpleasant taste and odor in drinking water are common. US Environmental Protection Agency (EPA) is funding research to improve detection of cyanotoxins. Detection must be performed in an analytical laboratory.

Although they are vnvisible in surface water in low numbers, they multiply rapidly into clumps or “blooms” where water is warm, shallow and undisturbed. Blooms can look green, blue-green, yellow, brown or red.

Health effects:

According to Water Technology magazine, "Algae-containing water can be swallowed, can contact the skin or is inhaled in aerosol-like droplets while swimming or showering. Cyanotoxins can cause gastrointestinal and lung ailments; allergic responses; skin and eye irritation; liver damage; tumor growth; and neurotoxic (nerve) reactions. Effects of long-term consumption uncertain."

Regulation:

Though many countries and some US states have established mandatory or voluntary standards, the US EPA continues to monitor cyanobacteria only as an "unregulated contaminant." The World Health Organization guideline for the cyanotoxin microcystin LR in drinking water is 1 microgram per liter.

Water treatment for algae and cyanotoxins.


• Activated carbon is effective and can resolve cyanobacteria-caused taste and odor issues.
• Reverse osmosis (RO), nanofiltration and ultrafiltration will remove/reduce single-cell cyanobacteria, and may also help reduce cyanotoxins.
• Disinfection methods (such as chlorination) may kill cyanobacteria but not eliminate the cyanotoxins they release.

One pool expert writes, "The ONLY sure-fire method of destroying waterborne algae is by running the water through an ultraviolet light. UV lights sterilize the algae and prevent it from reproducing. It will clear up the water and keep it clear. When installed correctly, a UV will show outstanding results within a matter of a day or two."


Main Source: Water Technology Volume 32, Issue 10 - October 2009. Other information added from various sources.

Sources Cited by Water Technology: US EPA, US Centers for Disease Control and Prevention, New York State Department of Health, California Department of Public Health, University of California.