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The Importance of Removing Heavy Metals From Aquarium and Pond Water
Absolutely one of the primary concerns in the use of a water conditioner for aquariums and ponds needs to be in removing the toxic heavy metals in the water obtained from the tap, which will be from the local public water supply, or from natural water sources such as wells, streams, rivers, and dams. This water will have passed through heavy-metal-based water pipes. The water pipes constant corrosion releases the heavy metals into the water, which are highly toxic to fishes, aquatic invertebrates, and other aquatic life, including the beneficial nitrifying bacteria important in biological filtration.
Throughout every year the rust increases in the water pipes and the amount of heavy metals increases that permeates into the water supply. Furthermore, those municipalities that installed plastic pipes for local water distribution about 30 or more years ago are finding that the plastic is disintegrating, causing leakage. The water-pipe replacements are not plastic, but longer-lasting heavy metals such as copper. The use of heavy metals in water distribution is presently increasing, not decreasing.
Heavy metals are variously classified, but are generally considered to be metals having high specific gravities, usually above 4 (4 g/cm3) or greater. They generally include by various definitions Al aluminum, Sb antimony, As arsenic, Be beryllium, Bi bismuth, Cd cadmium, Cr chromium, Co cobalt, Cu copper, Fe Iron, Pb lead, Mn manganese, Hg mercury, Ag silver, Sr strontium, V vanadium, Zn zinc and Sn tin, as well as metal combinations in brass (copper and zinc) and bronze (copper alloys, usually with tin; other heavy metals may be aluminum, zinc).
The definitive studies on the effects of heavy metals on fishes show that heavy metals in the water lower the fishes' survival rate, and mainly are seen to be haemotoxic to blood erythrocytes, decreasing the red blood cell count. It has been found in humans and mammals that the young absorb heavy metals more efficiently than the adults, thereby being more prone to heavy-metal poisoning. After exposure young and adults are susceptible to damaging effects of heavy-metal toxicity, including gastrointestinal upsets, mental illness, hypertension, lethargy, disruption of food consumption, etc. There is undoubtedly a counterpart to these symptoms from heavy metals in fishes and aquatic invertebrates, particularly so because they are more directly exposed to the toxic heavy metals through their gills and skin being in direct contact with the water containing the heavy metals.
Now there are scientific articles appearing that are providing some stunning information about how harmful trace elements of heavy metals are to fishes, even when they are only in parts per billion in the water (see the Science News reference at the end of this article). What it shows is that at low parts per billion -- heavy metals, such as copper at or below 10 ppb (parts per billion), and apparently zinc also, can cause fish to lose their sense of smell. What else the heavy metals are doing short of being lethal to fishes is little known and currently undergoing scientific investigation. What is clear is that the aquarist and pond keeper needs to keep their aquariums and ponds free of heavy metals. Therefore, using copper as a health treatment of fishes needs to be seriously considered in light of the adverse research results now emerging.
The U.S. EPA (Environmental Protection Agency) in its six-year review of chemical contaminants and health effects issued June 2003 ( www.epa.gov/safewater/standard/review/pdfs/support_6yr_healtheffects_final_pdf ) provided the following water quality standards for heavy metals in drinking water (also see heavy metals not listed in the above URL in the following EPA water quality standards www.fone.net/-thovezak/intern6.html)
Heavy Metals in Drinking Water
Element |
mg/L |
Parts per Billion (ppb) |
| Arsenic |
0.150 mg/L |
150 ppb |
| Cadmium |
0.005 mg/L |
5 ppb |
| Chromium |
0.100 mg/L |
100 ppb |
| Copper |
1.300 mg/L |
1,300 ppb |
| Iron |
1.000 mg/L |
1,000 ppb |
| Lead |
0.000 mg/L |
0 ppb |
| Mercury (inorganic) |
0.002 mg/L |
2 ppb |
| Nickel |
0.052 mg/L |
52 ppb |
| Selenium |
0.050 mg/L |
50 ppb |
| Zinc |
0.120 mg/L |
120 ppb |
:
Note that the allowable level for copper at 1300 ppb is 260 times what has recently been found for heavy metals to be generally harmful to fishes (5 ppb - see article below). What this means is that tap water (= drinking water as regulated by the EPA) can be harmful to fishes even within the guidelines established by the EPA. It is quite probable that aquarium and pond fishes for which tap water is used without treatment is considerably impairing the fishes' health.
 The scientists associated with Kordon found that the best way to control and eliminate heavy metals in the water is by the use of nontoxic forms of one or more Edetate compounds as used in agricultural chemicals, hydroponics, and medical chelation therapy. The basic chemical formula from which proper compounds are derived for aquarium and pond water conditioning is usually described chemically as Ethylene Diamine TetraAcetate. In the form of tetrasodium salts, which is used as a chelating agent to eliminate all heavy metals. The scientists associated with Kordon pioneered in developing the use of the proper Edetate compounds in aquarium and pond water conditioners many years before others followed in aquaculture and elsewhere. Kordon continues to pioneer in improvements.
The Edetate compounds Kordon uses are soluble in water and act rapidly in permanently removing the heavy metals present by forming stable complexes with the metal ions. The way it does this is that as a chelator (the procedure of removing heavy metals by chemical processes with a ring of hydrogen bonds) it binds itself to the metal or mineral elements, rendering them nontoxic and preventing further reactions. For example, while other heavy metals are also removed, the amount of copper, zinc, lead, iron, aluminum and nickel that will be chelated by one standard dosage (see Kordon Article "Standard Dose for Liquid Treatments" for further information on Standard Doses for Kordon products) of Kordon NovAqua Plus or Fish Protector is as follows:
0.112 mg/L Cu Copper
0.115 mg/L Zn Zinc
0.366 mg/L Pb Lead
0.098 mg/L Fe Iron
0.0492 mg/L Al Aluminum
0.1438 mg/L Ni Nickel
These numbers were calculated based on current formulations for Kordon NovAqua Plus, and Fish Protector at the standard dosage rate of one teaspoon (=5 ml) per 10 gallons of water (for other measurements see the Kordon Article "Standard Dose for Liquid Treatments").
This means that Kordon NovAqua Plus and Fish Protector will do the following per dose compared to the amounts listed by the EPA for heavy metals according to their water quality standards for drinking water:
One Standard Dose of NovAqua Plus or Fish Protector will detoxify as follows:
- Copper: it will take 8.6 doses to remove all copper
- Zinc: it will take slightly more than one dose to remove all zinc
- Lead: it will take out more than all allowable lead
- Iron: it will take slightly more than ten doses to remove all iron
- Nickel: it will take one dose to take out three times the allowable nickel
It is important to understand that water quality varies greatly across the United States and elsewhere, including day by day at the same location. The local public water utility would need to be contacted for information about the amount of trace elements in the local water supply. However, it is often difficult to obtain this information, and what they will often provide is for a one-time test during the previous year for only some of the heavy metals.
There are no side effects by NovAqua Plus and Fish Protector in the water. The compounds Kordon uses in its products are completely safe to use with fishes and other aquatic life. They are of no harm to humans or pet animals, and they do not persist in the environment. Microorganisms in the water completely mineralize Edetates over time as a source of carbon, nitrogen and energy. There is no approval of Kordon's products for human use, and should not be used as such. However, their broad efficacy is shown in a particular use of the basic Ededate compound as an antidote to heavy metal poisoning in humans. The basic formula is listed in the U.S. Pharmacopeia, and by the World Health Organization. It is approved by the U.S. Food & Drug Administration for human use in treating lead poisoning, as well as toxicity of other heavy metals.
All Kordon products containing Edetates are compatible with all Kordon, Oasis, TeraRep and AquaVet products (except for the copper aquatic treatments).
Kordon Water Conditioner Products That Remove Heavy Metals
click on description to view the product information page
Other Relative Articles
Article from NewScientist 7 April 2007, magazine issue 2598, page 12
'Safe' heavy metals hit fish senses, by Aria Pearson
POLLUTION far below the level seen as dangerous for aquatic life has nevertheless dramatically altered behaviour in North American lakes. Heavy metals are knocking out the sense of smell in organisms from bacteria to fish. Even we may not be immune.
Nathaniel Scholz, at the Northwater Fisheries Science Center in Seattle, Washington, and colleagues found that salmon lose their sense of smell if there are even low levels of copper in the water they are swimming in. The fish could die as a result, because they cannot smell chemicals that would warn of a nearby predator.
All over the world, storm water run-off shuttles heavy metals such as copper and zinc from industry, mines and built-up areas into natural water courses. The concentrations are generally low -- too low for polluters to bother about, or so many of them seem to have thought. "Now we're going after [this] 'So what?' question," says Scholz.
Scholz's team kept young coho salmon in tanks with different concentrations of copper for 3 hours, then measured their movements when a drop of salmon skin extract was added to the water. In the wild, the skin would be a cue that a predator may have injured a fish nearby.
Unexposed salmon stopped swimming, sank to the bottom of the tank and kept still - typical tactics for avoiding predators. But fish exposed to concentrations of copper as low as 2 parts per billion (ppb) just stopped for a few seconds, or merely slowed down, while fish exposed to 10 or more ppb didn't notice the cue at all (Environmental Science and Technology, DOI:10.1021/eso62287r).
The U.S. Environmental Protection Agency has set the maximum safe level of copper for aquatic life at 13 parts per billion, well above that needed to wipe out the salmon's ability to sense chemical cues. Yet Greg Pyle, at Nipissing University in North Bay, Ontario, Canada, has found chemosensory problems at three levels of the food chain at or below 5 ppb, the limit set by Ontario's water quality standards. "The phenomenon is ubiquitous," he says.
Leeches lost their ability to smell food, zooplankton were unable to evade predators, and fathead minnows couldn't recognize their eggs; the fish ate them instead of protecting them. The contamination in these lakes is much too weak to kill these organisms outright, Pyle says, yet their populations are suffering.
Metals have the same effect in humans. The makers of the cold remedy Zicam, which contains zinc, recently settled out of court for $12 million with people who reported losing their sense of smell after spraying the product into their noses. The company maintains the remedy is safe. Studies have not been conducted to test whether zinc destroys human sensory abilities, but given what's happening in aquatic ecosystems, Pyle believes it could. "Don't squirt metals up your nose," he says. "That would be my advice."
The following article copied from PubMed is useful in revealing where the heavy metals are accumulating in fish. To view article click here.
journal: Environment International Elsevier
Volume 27, Issue 1, July 2001, Pages 27-33
Monitoring of environmental heavy metals in fish from Nasser Lake.
by M. N. Rashed, Chemistry Department, Faculty of Science, Aswan, Egypt.
Abstract:
Lake ecosystems are, in particular, vulnerable to heavy metal pollution. Tilapia nilotica [African cichlid fish] is one of the aquatic organisms affected by heavy metals. Therefore, heavy metals Co [cobalt], Cr [chromium], Cu [copper], Fe,[iron] Mn [manganese], Ni [nickel], Sr [strontium] and Zn [zinc] were determined in different tissues of T. nilotica (ages 1, 1.5, 2, 2.5 and 3 years), which include the muscle, gill, stomach, intestine, liver, vertebral column and scales, to assess the fish pollution with heavy metals. In addition, the study was extended to determine these elements in the aquatic plant (Najas armeta), sediment and water of Khor E1-Ramel in Nasser Lake (Egypt). The study showed that of all the fish parts, fish liver accumulated the highest levels of Cu and Zn. Manganese presented in the intestine and stomach in the highest concentration. Scales exhibited the highest levels of Co, Cr, Ni and Sr, while the gill and vertebral column contains the lowest level of the studied elements. Heavy metals in different parts of T. nilotica differ with the fish growth and extraction rate of these elements from sediment, aquatic plant and lake water. Heavy metals under study in the edible parts of the investigated fish were in the safety permissible levels for human uses.
PMID: 11488387 [PubMed - indexed for MEDLINE]
Further Considerations About the Effects of Heavy Metals on the Sensory Organs of Fishes
While the scientific evidence from research at this time is preliminary and limited, the insight that heavy metals have such an adverse effect on fish's olfactory organs is enough known to have serious concerns about other harm being done by the presence of heavy metals in water containing fishes, amphibians, and aquatic invertebrates.
The olfactory organs are just one facet of the sensory organs in aquatic animals that might be affected by heavy metals. If the olfactory organs are disabled by less than 10 parts per billion of heavy metals in the water, what about all the other sensory organs exposed on the head and body surfaces that provide sensory information to the brain? These include besides the ones for smell -- those for sight, taste, touch, and hearing, including:
- Surface barbels on the head in fishes that contain sensory organs used to find food
- Internal and external taste "buds" and cells in fishes and amphibians
- Lateral-line organs on the sides of fishes and amphibians. [Lateral-line organs are hollow tubes in the surface skin of the head and body extending from the gills to the tail. The organs contain specialized hair cells (cilia) that sense slight water movements outside the body, such as by fish or other animals swimming nearby.]
- Electrosensory skin ampoules and pores on and in the skin on the head and body that sense the presence of other organisms over relatively long distances, particularly noted in sharks
- Nervous system and brain affected through the gills into the blood and through the blood vessels to the brain. the heavy metal lead in the water is considered as a possible cause of severe brain damage in fishes and other aquatic animals
"The Shark's Electric Sense" and "Electrosensors in Action"
We wish to emphasize that serious consideration should be given to the consequences before using a treatment on fishes that includes heavy metals, such as copper. Admittedly, a copper treatment is very effective in killing single and multi-celled parasites. But the adverse effects on the fishes -- even at very low concentrations in the water in the parts per billion -- are too great to compensate for this. The evidence is that except in special circumstances well understood beforehand, a treatment containing any heavy metal should not be used.
A recent article on electrosensors in fishes is "The Shark's Electric Sense" and "Electrosensors in Action," by R. Douglas Fields, Scientific American Aug. 2007 pp. 74-81. Also see bibliography at the end of this article. www.sciam.com.
Brass corrosion as a source of lead and copper in
traditional and all-plastic distribution
systems by David Eugene Kimbrough, American
Water Works Association e-Journal Aug. 15, 2007.
http://www.awwa.org/communications/journal/2007/August/JAW200708_ES03_Kimbrough.cfm
Executive Summary: "Corrosion by copper pipes
has long been considered the main source of
copper in samples collected under the Lead and
Copper Rule (LCR). Furthermore, regulatory
agencies generally have assumed that the primary
source of lead is lead solder or pipes. Recent
research, however, has suggested that brass
corrosion may play a larger part in contributing
to lead and copper at the customer's tap than initially supposed.
"One obstacle to accurately identifying sources
of lead and copper in LCR samples is the
possibility of several sources for both elements.
This study focused on two populationshouses with
traditional plumbing and houses with all-plastic
plumbing, a factor that effectively eliminated
all but one source. Analysis of first-draw
samples collected from houses with all-plastic
plumbing showed concentrations of lead and copper
comparable to those found in traditionally
plumbed houses, indicating that the lead and
copper found in the plastic system resulted from
brass corrosion. Given that the LCR has a limited
focus on brass, these results call into question
the efficacy of the LCR in reducing consumer exposure to lead and copper.MPM"
[Kordon Note on the above article: LCR refers to
the U.S. Environmental Protection Agency's "Lead
and Copper Rule" in drinking water
(http://www.epa.gov/safewater/lcrmr/index.html).
For those concerned about heavy metals in tap water that are used in aquariums and ponds,
reading the EPA's comments on this matter will
provide a perspective of how greatly the EPA has changed its position on the adverse effects of
lead and copper on human consumption of drinking water.
In 1991 when the EPA "Lead and Copper Rule" was established, the rule replaced the previous
allowable standard of 50 ppb lead and copper,
measured at the entry point to the water distribution system. It 1991 the EPA established
a maximum contaminant level goal (MCLG) of zero
for lead in drinking water. The action level now
required for lead is 15 ppb and 1.3 ppm for
copper for more than 10% of customer taps sampled.
The EPA states: "Lead and copper enter drinking
water primarily through plumbing
materials. Exposure to lead and copper may cause
health problems [to humans] ranging from stomach
distress to brain damage." If it is affecting
humans mainly through their drinking water,
consider what it is doing to fishes and other
aquatic life who have to live in this water.
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