Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Perchlorate shopping experience:
1. Compare - without doubt the biggest advantage that the Perchlorate offers shoppers today is the ability to compare thousands of Perchlorate at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Perchlorate? Wrong! If the Perchlorate is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Perchlorate then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Perchlorate? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Perchlorate and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Perchlorate wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Perchlorate then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Perchlorate site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Perchlorate, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Perchlorate, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
of the perchlorate ion
Perchlorates are the salts derived from perchloric acid (
HydrogenchlorineOxygen). They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to treat
thyroid gland disorders. They are also used as an oxidizer in rocket fuel and can be found in
airbags,
fireworks, and Chilean fertilizers. Both potassium perchlorate (Potassium
chlorineOxygen) and
ammonium perchlorate (ammoniumchlorine
Oxygen) are used extensively within the pyrotechnics industry, whereas ammonium perchlorate is a component of solid rocket fuel.
Lithium perchlorate, which decomposes exothermically to give oxygen, is used in
chemical oxygen generator on spacecraft, submarines and in other esoteric situations where a reliable backup or supplementary oxygen supply is needed. Most perchlorate salts are soluble in water.
Scientific definition
The perchlorate
ion is ClO4−, and it has a molecular mass of 99.45 a.u.
A perchlorate (compound) is a compound containing this group, with chlorine in oxidation state +7.
Strength of oxidation
The perchlorate ion is the weakest oxidizer of the generalized chlorates. Lower oxidation numbers are progressively stronger oxidizers, and less stable.Perchlorate has the highest
redox potential, but is a closed shell species, and as such, is sluggish to oxidize other species.
Stability
Most perchlorates, especially salts of electropositive metals such as sodium perchlorate or potassium perchlorate, are slow to react unless heated, the perchlorate ion being largely inert and not oxidizing at lower temperatures. This property is useful in many applications, such as Flare (pyrotechnic)s, where the device should not explode, or even catch fire spontaneously.
Mixtures of perchlorates with organic compounds are more reactive; although generally they do not catch fire or explode unless heated, there are a number of exceptions.
Environmental presence
Low levels of perchlorate have been detected in both drinking water and groundwater in 35 states in the US according to the
United States Environmental Protection Agency. In 2004, the chemical was also found in cow's milk in the area with an average level of 1.3
parts per billion ("ppb" or µg/L), which may have entered the cows through feeding on crops that had exposure to water containing perchlorates.Associated Press. " Toxic chemical found in California milk".
MSNBC. June 22, 2004. According to the Impact Area Groundwater Study Program , the chemical has been detected as high as 5 µg/L in Massachusetts, well over the state regulation of 1 µg/L.
In some places it is being detected because of contamination from industrial sites that use or manufacture perchlorate. In other places, there is no clear source of perchlorate. In those areas it may be naturally occurring or could be present because of the use of Chilean fertilizers, which were imported to the U.S. by the hundreds of tons in the early 19th century. One recent area of research has even suggested that perchlorate can be created when lightning strikes a body of water, and perchlorates are created as a byproduct of chlorine generators used in swimming pool chlorination systems.
As of April 2007, the EPA has not yet determined whether perchlorate is present at sufficient levels in the environment to require a nationwide regulation on how much should be allowed in drinking water. EPA Press Release "EPA Issues Determination on 11 Contaminants" April 4, 2007 In 2005, U.S. EPA issued a recommended Drinking Water Equivalent Level (DWEL) for perchlorate of 24.5 µg/L. In early 2006, EPA issued a “Cleanup Guidance” for this same amount. Both the DWEL and the Cleanup Guidance were based on a thorough review of the existing research by the
National Academy of Science (NAS). This followed numerous other studies, including one which suggested human breast milk had an average of 10.5 µg/L of perchlorate.McKee, Maggie. " Perchlorate found in breast milk across US".
New Scientist. February 23, 2005 Both the Pentagon and some environmental groups have voiced questions about the NAS report, but no credible science has emerged to challenge the NAS findings.
Health effects
A study involving healthy adult volunteers determined that at levels above 0.007 milligrams per kilogram per day (mg/kg-d), perchlorate can temporarily and reversibly inhibit the thyroid gland’s ability to absorb iodine from the
bloodstream ("iodide uptake inhibition"). The EPA converted this dose into a "drinking water equivalent level" of 245 ppb by assuming a person weighs 70 kilograms (154 pounds) and consumes 2 liters (68 ounces) of drinking water per day over a lifetime. US EPA Memorandum Jan 26, 2006
While the thyroid uses iodine to produce
hormones, NAS says this process of iodide uptake inhibition is not an "adverse," or harmful, effect. There has been some speculation that exposure to extremely high doses of perchlorate, for several months or years could lead to
hypothyroidism, but NAS found that iodide uptake inhibition was the only consistently documented health effect of perchlorate in humans. Furthermore, a 2006 CDC study found this to only be true in women, and because the study was not properly controlled for autoimmune thyroid disease (which causes identical effects on iodine uptake and which is much more common in women), improved analysis may show that the effect is extremely small or even nonexistent.
The NAS also found that perchlorate only affects the thyroid gland. There is no evidence that it causes
brain damage, birth defects or cancer in humans. It is also not stored in the body, it is not metabolism, and any effects of perchlorate on the thyroid gland are fully reversible once exposure stops. There has been some concern on perchlorates effects on fetuses, newborns and children, but several peer-reviewed studies on children and newborns also provide reason to believe that low levels of perchlorate do not pose a threat to these populations. On October 1, 2004, the American Thyroid Association (ATA) reported that perchlorate may not be as harmful to newborns, pregnant women and other adults as previously thought.
The EPA and NAS divided the No Observed Effect Level (
NOEL) for perchlorate of 0.007 mg/kg-d by the standard intraspecies uncertainty factor of 10 to derive a “reference dose” of 0.0007 mg/kg-d, and declared this would be protective of even the most sensitive subpopulations. Usually an additional 10-fold interspecies uncertainty factor is also used in the calculation of reference doses, but since the perchlorate NOEL was derived from a human study, rather than an animal study, this additional uncertainty factor was not used. Using the 70 kg body weight and 2 liter/day assumptions used above, this dose is converted to 25 ppb in drinking water. For that reason, most media reports call this the "safe" level of exposure. The NAS report also stated additional research would be helpful, but emphasized that the existing database on perchlorate was sufficient to make its reference dose recommendation and ensure it would be protective for everyone.
Recent research, however, has shown inhibition of iodide uptake in the thyroids of women at much lower levels, levels attainable from normally contaminated water and milk.
Types of perchlorates
References
- Associated Press. " State Threatening To Sue Military Over Water Pollution". May 19, 2003.
- " Health Effects Of Perchlorate From Spent Rocket". SpaceDaily.com. July 11, 2002.
External links
- NAS Report: The Health Effects of Perchlorate Ingestion
- Facts and truth about perchlorate (Sponsored by the chemical companies that produce it)
- NRDC's criticism of NAS report
- Environment California report (Executive Summary with link to full text)
- Thyroid Threat:Under Proposed Rocket Fuel Standards, Many Women Would Need Treatment To Protect Baby
of the perchlorate ion
Perchlorates are the
salts derived from perchloric acid (
HydrogenchlorineOxygen). They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to treat thyroid gland disorders. They are also used as an oxidizer in rocket fuel and can be found in airbags,
fireworks, and Chilean
fertilizers. Both potassium perchlorate (
Potassiumchlorine
Oxygen) and ammonium perchlorate (ammonium
chlorineOxygen) are used extensively within the pyrotechnics industry, whereas ammonium perchlorate is a component of solid rocket fuel. Lithium perchlorate, which decomposes exothermically to give oxygen, is used in chemical oxygen generator on spacecraft, submarines and in other esoteric situations where a reliable backup or supplementary oxygen supply is needed. Most perchlorate salts are soluble in water.
Scientific definition
The perchlorate ion is ClO4−, and it has a molecular mass of 99.45 a.u.
A perchlorate (compound) is a compound containing this group, with chlorine in
oxidation state +7.
Strength of oxidation
The perchlorate ion is the weakest oxidizer of the generalized chlorates. Lower oxidation numbers are progressively stronger oxidizers, and less stable.Perchlorate has the highest redox potential, but is a closed shell species, and as such, is sluggish to oxidize other species.
Stability
Most perchlorates, especially salts of electropositive metals such as
sodium perchlorate or potassium perchlorate, are slow to react unless heated, the perchlorate ion being largely inert and not oxidizing at lower temperatures. This property is useful in many applications, such as
Flare (pyrotechnic)s, where the device should not explode, or even catch fire spontaneously.
Mixtures of perchlorates with organic compounds are more reactive; although generally they do not catch fire or explode unless heated, there are a number of exceptions.
Environmental presence
Low levels of perchlorate have been detected in both drinking water and
groundwater in 35 states in the US according to the United States Environmental Protection Agency. In 2004, the chemical was also found in cow's
milk in the area with an average level of 1.3
parts per billion ("ppb" or µg/L), which may have entered the cows through feeding on crops that had exposure to water containing perchlorates.Associated Press. " Toxic chemical found in California milk".
MSNBC. June 22, 2004. According to the Impact Area Groundwater Study Program , the chemical has been detected as high as 5 µg/L in Massachusetts, well over the state regulation of 1 µg/L.
In some places it is being detected because of contamination from industrial sites that use or manufacture perchlorate. In other places, there is no clear source of perchlorate. In those areas it may be naturally occurring or could be present because of the use of Chilean fertilizers, which were imported to the U.S. by the hundreds of tons in the early 19th century. One recent area of research has even suggested that perchlorate can be created when lightning strikes a body of water, and perchlorates are created as a byproduct of chlorine generators used in swimming pool chlorination systems.
As of April 2007, the EPA has not yet determined whether perchlorate is present at sufficient levels in the environment to require a nationwide regulation on how much should be allowed in drinking water. EPA Press Release "EPA Issues Determination on 11 Contaminants" April 4, 2007 In 2005, U.S. EPA issued a recommended Drinking Water Equivalent Level (DWEL) for perchlorate of 24.5 µg/L. In early 2006, EPA issued a “Cleanup Guidance” for this same amount. Both the DWEL and the Cleanup Guidance were based on a thorough review of the existing research by the National Academy of Science (NAS). This followed numerous other studies, including one which suggested human breast milk had an average of 10.5 µg/L of perchlorate.McKee, Maggie. " Perchlorate found in breast milk across US".
New Scientist. February 23, 2005 Both the Pentagon and some environmental groups have voiced questions about the NAS report, but no credible science has emerged to challenge the NAS findings.
Health effects
A study involving healthy adult volunteers determined that at levels above 0.007 milligrams per kilogram per day (mg/kg-d), perchlorate can temporarily and reversibly inhibit the
thyroid gland’s ability to absorb iodine from the
bloodstream ("iodide uptake inhibition"). The EPA converted this dose into a "drinking water equivalent level" of 245 ppb by assuming a person weighs 70 kilograms (154 pounds) and consumes 2 liters (68 ounces) of drinking water per day over a lifetime. US EPA Memorandum Jan 26, 2006
While the thyroid uses iodine to produce
hormones, NAS says this process of iodide uptake inhibition is not an "adverse," or harmful, effect. There has been some speculation that exposure to extremely high doses of perchlorate, for several months or years could lead to
hypothyroidism, but NAS found that iodide uptake inhibition was the only consistently documented health effect of perchlorate in humans. Furthermore, a 2006 CDC study found this to only be true in women, and because the study was not properly controlled for autoimmune thyroid disease (which causes identical effects on iodine uptake and which is much more common in women), improved analysis may show that the effect is extremely small or even nonexistent.
The NAS also found that perchlorate only affects the thyroid gland. There is no evidence that it causes brain damage,
birth defects or cancer in humans. It is also not stored in the body, it is not metabolism, and any effects of perchlorate on the thyroid gland are fully reversible once exposure stops. There has been some concern on perchlorates effects on fetuses, newborns and children, but several peer-reviewed studies on children and newborns also provide reason to believe that low levels of perchlorate do not pose a threat to these populations. On October 1, 2004, the American Thyroid Association (ATA) reported that perchlorate may not be as harmful to newborns, pregnant women and other adults as previously thought.
The EPA and NAS divided the No Observed Effect Level (
NOEL) for perchlorate of 0.007 mg/kg-d by the standard intraspecies uncertainty factor of 10 to derive a “reference dose” of 0.0007 mg/kg-d, and declared this would be protective of even the most sensitive subpopulations. Usually an additional 10-fold interspecies uncertainty factor is also used in the calculation of reference doses, but since the perchlorate NOEL was derived from a human study, rather than an animal study, this additional uncertainty factor was not used. Using the 70 kg body weight and 2 liter/day assumptions used above, this dose is converted to 25 ppb in drinking water. For that reason, most media reports call this the "safe" level of exposure. The NAS report also stated additional research would be helpful, but emphasized that the existing database on perchlorate was sufficient to make its reference dose recommendation and ensure it would be protective for everyone.
Recent research, however, has shown inhibition of iodide uptake in the thyroids of women at much lower levels, levels attainable from normally contaminated water and milk.
Types of perchlorates
References
- Associated Press. " State Threatening To Sue Military Over Water Pollution". May 19, 2003.
- " Health Effects Of Perchlorate From Spent Rocket". SpaceDaily.com. July 11, 2002.
External links
- NAS Report: The Health Effects of Perchlorate Ingestion
- Facts and truth about perchlorate (Sponsored by the chemical companies that produce it)
- NRDC's criticism of NAS report
- Environment California report (Executive Summary with link to full text)
- Thyroid Threat:Under Proposed Rocket Fuel Standards, Many Women Would Need Treatment To Protect Baby
Perchlorate - Wikipedia, the free encyclopedia
Perchlorates are the salts derived from perchloric acid (H Cl O 4). They occur both naturally and through manufacturing. They have been used as a medicine for more than 50 years to ...
Ammonium perchlorate - Wikipedia, the free encyclopedia
Ammonium perchlorate (AP) is a chemical compound with the formula N H 4 Cl O 4. It is the salt of ammonia and perchloric acid. Like other perchlorates, it is a powerful oxidizer.
Definition: perchlorate from Online Medical Dictionary
The Online Medical Dictionary is a searchable dictionary of definitions from medicine, science and technology.
perchlorate - definition of perchlorate in the Medical dictionary - by ...
per·chlo·rate (p r-klôr t)
EPA Ground Water & Drinking Water > Perchlorate
Perchlorate . EPA is currently undertaking efforts to help the Agency determine if regulation of perchlorate in drinking water would represent a meaningful opportunity for ...
perchlorate - Hutchinson encyclopedia article about perchlorate
chlorate. The anion of chloric acid (HClO 4), or any salt containing this anion. Common chlorates are those of sodium, potassium, and magnesium. In these compounds, chlorine has ...
Perchlorate found in breast milk across US - health - 23 February 2005 ...
The chemical - associated with rocket fuel - is found in relatively high levels, possibly increasing the risk of mental retardation in infants
University of Exeter: Effects of Ammonium Perchlorate on Thyroid ...
Automatic import from http://www.pubmedcentral.gov/oai/oai.cgi into DSpace/OR repository {ERIC} on 2007-05-128
perchlorate definition of perchlorate in the Free Online Encyclopedia.
Researchers know the rocket fuel component perchlorate can be harmful to humans, they just can't agree on how much of it makes drinking water unsafe.
Platinum today: Palladium catalyst removes perchlorate from water
Read more about the platinum group metals markets in Johnson Matthey's bi-annual reviews ... A new catalyst composed of palladium and rhenium, supported on activated carbon, has ...
