At the core of the Doulton® ceramic filter candle is the most basic of elements -- EARTH. This is the same substance which artisans, first in Asia then in Europe, refined into exquisite porcelain and pottery of the Shoguns and Kings. This material is diatomaceous earth [d.e.], a fossil substance, made up of tiny silicon shells left by trillions of microscopic, one celled algae called diatoms that have inhabited the waters of the Earth since it's creation.
Diatoms have one property that sets them apart from other micro-organisms. They weave microscopic shells which they use for protection and locomotion. These shells are covered with a pattern of tiny holes so regular that even the slightest change in their design usually signifies a different species. As the diatoms died, their shells survived, slowly piling up in deposits at the bottom of geological lakes and lagoons. When these lakes dried up, what remained were huge deposits of "diatomaceous earth". Today there are over 1500 uses for diatomaceous earth, abrasives for toothpaste, filtering agents for water and milk, heat insulators for kilns, polishing agents in nail polishes, and many more.
The ceramic shell in our filter candles exhibit a strictly controlled pore structure (80,000,000 pores) which is unparralled in any other brand of element. This pore structure provides efficient sub-micro filtration (nominal .22 micron), a proven defense against hard-shelled parasites, pathogenic bacteria, and other less harmful but equally unpleasant particulate debris such as rust and dirt. Laboratories consider filtering medium with an effective pore size of 0.1 micron to be bacteriologically sterile and .45 micron to 1.0 micron to be bacteriologically safe. The candles consist of a fine microporous structure, which forms a complete barrier to all particles larger than 0.5 microns in size (ANSI)(1 micron = 1/1,000 of a millimeter). All particles above this size become trapped on the surface and within the ceramic material. Fine particles of silver (about 0.07%) are evenly dispersed within the ceramic structure of the candle, which prevents the growth of bacteria (mitosis) within the ceramic wall. This self-sterilizing effect is known as the Bacteriostatic effect. The silver leach rate from the ceramic is very low and always well below the allowable levels recommended by the World Health Organization and the E.P.A. The Doulton® candles also contain an additional activated charcoal filling, which removes volatile organic chemicals and compounds (VOC's) from the water and improves it's taste and odor.
The high-tech silver-impregnated ceramic elements feature a nominal filtration efficiency of: 0.22 microns >98%, at 0.5 microns >99.99%, and at 0.9 microns >100% which effectively blocks waterborne pathogens and clarifies the water.
Organic and Inorganic Chemicals and Compounds
Organic chemicals in our drinking water may be naturally occurring or result from agricultural or industrial pollution Naturally occurring organics result from the water passing through peat or decaying vegetation before reaching the reservoir. These organics are usually humic acids or tannin, the unpleasant aspects of which are color, taste and odor.
Organic and inorganic chemicals and compounds introduced by agricultural or industrial pollution are herbicides, pesticides, and organic solvents. More recently we have learned of the presence of PAHs (Poly Aromatic Hydrocarbons) which are by-products of the decomposition of the bituminous lining of the water supply mains.
Some of these organics have been associated with long term health effects such as cancer. E.P.A. and E.E.C. regulations call for very low maximum allowable levels. Furthermore, the reaction of some of these organics with the residual chlorine in the drinking water can produce chlorinated hydrocarbons which are regarded as more harmful than the original organic.
Organic compounds can be effectively removed by adsorption onto activated carbon.
The cavity of the Super Steracyl candle contains granulated activated carbon (GAC). Used in gravity filter applications, the Super Steracyl effectively removes organic compounds and chemicals from the water.
Volatile Organic Chemical (VOC) reduction claim (NSF 53) health includes the following chemicals:
alachlor
1, 2-dichloropropane
styrene
atrazine
cis-1, 3-dichloropropylene
1, 1, 2, 2-tetrachloroethane
benzene
dinoseb
tetrachloroethylene
carbofuran
endrin
toluene
carbon tetrachloride
ethylbenzene
1, 2, 4-trichlorobenzene
chlorobenzene
ethylene dibromide (EDB)
1, 1, 1-trichloroethane
dibromochloropropane (DBCP)
heptachlor
1, 1, 2-trichloroethane
o-dichlorobenzene
heptachlor epoxide
trichloroethylene
p-dichlorobenzene
hexachlorobutadiene
trihalomethanes
1, 1-dichloroethane
hexachlorocyclopentadiene
m-xylene
1, 2-dichloroethane
lindane
o-xylene
trans-1, 2-dichloroethylene
methoxychlor
p-xylene
1, 1-dichloroethylene
pentachlorophenol
2, 4-D
cis-1, 2-dichloroethylene
simazine
2, 4, 5-TP (silvex)
Pathogenic Bacteria, Cysts, Sediment (Suspended Solids)
Bacteria are single-celled micro-organisms that feed on digestive wastes and dead tissue. Some bacteria are beneficial but some can cause disease. Disease causing bacteria are called pathogenic bacteria. Since waterborne pathogenic bacteria (such as typhoid, cholera, and shigella) are greater than one micron in size, they cannot pass through the Doulton ceramic candle. Moreover, during testing, the concentration of bacteria fed to the filter is artificially high in order to simulate a challenging test for the filter. The most aggressive "real life" condition would normally be at least 1000 times less severe.
Nearly all drinking water contains ubiquitous bacteria that tend to multiply when retained in conducive situations. While the Doulton ceramic retains pathogenic bacteria, smaller heterotrophic bacteria do pass through. Since these heterotrophic bacteria are harmless, normally there are no problems. However, if normal use of the filter is interrupted by holidays or vacations, growth of these bacteria may result in a 'flat' or 'stale' taste for a period of time when use of the filter resumes. This is especially true for filters that contain activated carbon such as the Super Steracyl. This problem may be eliminated by discarding the first gallon or so of filtered water after any prolonged period of inactivity.
Microorganism
Illness
Giardia
Giardiasis
Salmonella
Typhoid
Vibrio Cholerae
Cholera
Schistosoma
Bilharzia
Shigella
Shigellosis
E. Coli
Traveler's Diarrhea
Burkholderia pseudomallei
Melioidosis
Cryptosporidium
Cryptosporidiosis
A Word About Cryptosporidium
This organic sporozoan, first described in 1907, wasn't recognized as a cause of human illness until 1976. It is a protozoan parasite that can infect a variety of animals. In the environment, Cryptosporidium exists as a resilient, infectious, round oocyst about four to six microns in diameter. The oocyst is a "suitcase" for the infectious material inside.
Cryptosporidium is widespread in the environment. oocysts have been found in rivers, streams, lakes, reservoirs, sewage, and treated surface water. Once introduced to water, the oocyst can survive for weeks, even at low temperatures. The organism has been found in humans, cattle, sheep, swine, goats, cats, and dogs as well as deer, raccoons, foxes, coyotes, beavers, muskrats, rabbits and squirrels. Oocysts infecting certain species can infect another (referred to as cross-contamination). For example, organisms from domestic animals (cattle, dogs, cats, etc.) are able to infect humans. Conversely, organisms from humans can infect animals. Consequently, animals typically found in watersheds may serve as sources of infection. Moreover, infection can occur not only from drinking contaminated water but also from eating contaminated food and from exposure to fecally contaminated environmental surfaces.
When ingested, the oocysts pass through the stomach into the small intestine. There the oocysts split open, releasing sporozoites which invade the cells lining the gastrointestinal tract. Infected cells ruling the intestine appear normal, but there ability to absorb water and nutrients is severely impaired. The water and food ingested simply passes through the digestive system. Additional oocysts are formed in the intestine and either split open to release additional sporozoites to continue the infection or are excreted in the feces.
The Cryptosporidium infection causes an illness known as cryptosporidiosis. After the oocysts arre ingested, the incubation period typically varies from two to 12 days with an average of seven days. Disease symptoms include diarrhea, abdominal cramps, nausea, occasional vomiting, and low grade fever. The number of oocysts that must be ingested to cause infection in humans is not known. Studies indicate that as few as ten and perhaps as many as 500 oocysts are required to initiate infections in mammals. The infectious dose for humans is thought to be less than ten.
Cryptosporidiosis typically lasts 10 to 14 days. However, it may linger off and on for up to 30 days and infrequently can persist for extended periods. Children may be the most susceptible, particularly two-year-olds and younger. A cure for Cryptosporidiosis has not been found. Recovery depends on the patient's immune system. The disease can be fatal for those with AIDS. There are two varieties of the oocyst; (1) a sphere of about 4.5 microns in diameter and (2) an ellipse of about 7 x 5 microns. The thick walls of the oocysts make it difficult, almost impractical, to kill the sporozoites with the Ultra Violet (UV) systems in most domestic water filters. Also, the cyst is much more difficult to kill using chlorine than normal coliform in drinking water.
So... the water you drink, even from your kitchen faucet, may be contaminated with Cryptosporidium Parvum. In 1993, NBC's television program "Date Line" documented just this fact. Concerns with public water systems in Milwaukee and New York were given as examples of failure to remove potentially deadly organisms from the drinking water.
Since Doulton® ceramic candles are manufactured so that they remove 100% of pathogenic bacteria greater than 0.9 microns in size, they have been shown effective, by the University of Arizona, in the removal of the specific organism named in the program, Cryptosporidium, from the water. The Super Steracyl® ceramic candles have also been tested and certified by the National Sanitation Foundation (NSF) to meet their Standard 053 (Health) for the removal of cysts.
After passing through the filter candles, safe, filtered water then collects in the lower chamber to be drawn off from a tap. The structure of the ceramic material is designed to be cleanable and regular cleaning of the element with a Scotchbrite® Pad will allow it's filtration efficiency to be regenerated. The elements may be cleaned over 100 times before replacement becomes necessary.
Our ceramic filter product is manufactured, tested, and certified by (or to meet):
IMPORTANT NOTICE TO OUR VALUABLE CALIFORNIA & IOWA CUSTOMERS:
Unlike the British Berkefeld® or other stainless steel systems, our HyperClear Gravity Systems
are legal for sale in your states because our systems are constructed of rugged food grade
plastic buckets and are intended for outdoor and emergency use only. They are not intended
as residential filtration systems in these states.
International customers of the Doulton® filter candle include: