Water, Water, Everywhere ...[H.sub.2] and O. If you think that's all your water contains, think again. A lot can happen on the way to the tap or bottle. Water can pickup healthy minerals like magnesium and calcium as it travels through rock formations. It can become laced with pesticides that are washed into rivers and streams. The chlorine that's used to disinfect To remove the virus code that has attached itself to a legitimate file. Sometimes, the antivirus program cannot untangle the code, and the infected file has to be deleted. See quarantine. it can react with decaying leaves to form toxic byproducts. And even the purest water can become contaminated contaminated, v 1. made radioactive by the addition of small quantities of radioactive material. 2. made contaminated by adding infective or radiographic materials. 3. an infective surface or object. with lead from the pipes in your home. The Environmental Protection Agency Environmental Protection Agency (EPA), independent agency of the U.S. government, with headquarters in Washington, D.C. It was established in 1970 to reduce and control air and water pollution, noise pollution, and radiation and to ensure the safe handling and (EPA EPA eicosapentaenoic acid. EPA abbr. eicosapentaenoic acid EPA, n.pr See acid, eicosapentaenoic. EPA, n. ) requires water utilities to keep the levels of 80 potential contaminants below legal limits. But even when water meets all regulations, it still may not be suitable for everyone to drink. On the whole, Americans have good clean drinking water drinking water supply of water available to animals for drinking supplied via nipples, in troughs, dams, ponds and larger natural water sources; an insufficient supply leads to dehydration; it can be the source of infection, e.g. leptospirosis, salmonellosis, or of poisoning, e.g. . "You can travel the length of this country, drink the water at every stop, and probably never get sick," says epidemiologist Rebecca Calderon of the Environmental Protection Agency (EPA). "But travel to many other countries and the story will be very different." Indeed, almost 90 percent of the 55,000 public water systems in the U.S. report no violations of the EPA's limits for drinking water contaminants. But that's no guarantee that the water won't make you sick. In two studies, Philadelphia water that met EPA standards appeared to increase gastrointestinal illnesses among children and the elderly.(1,2) And in another study, California water that met EPA standards was linked to an increased risk of miscarriages.(3) How safe is your drinking water? To find out, you're going to have to do a little detective work. First you need to know what to look for. Here are five of the most widespread or serious contaminants: 1 Disinfection disinfection, n the process of destroying pathogenic organisms or rendering them inert. disinfection, full oral cavity, n a procedure used to reduce active periodontal disease, usually completed within a certain short time frame. Byproducts Chlorinating water to destroy disease-causing bacteria was one of the greatest public-health achievements of the 20th century. But addingchlorine to water is a double-edged sword. The disinfectant can combine with decaying leaves and other naturally occurring organic matter to form compounds called disinfection byproducts (DBPs). "These byproducts are probably the most significant, most widely distributed contaminant contaminant /con·tam·i·nant/ (kon-tam´in-int) something that causes contamination. contaminant something that causes contamination. in the U.S. water supply today," says Kenneth Cantor, an epidemiologist at the National Cancer Institute in Bethesda, Maryland. "They can roughly double the risk of developing bladder cancer bladder cancer Malignant tumour of the bladder. The most significant risk factor associated with bladder cancer is smoking. Exposure to chemicals called arylamines, which are used in the leather, rubber, printing, and textiles industries, is another risk factor. ." The EPA estimates that between two and 17 percent of all bladder cancer cases in the U.S. may be due to DBPs in drinking water. DBPs may also increase the risk of colon cancer colon cancer, cancer of any part of the colon (often called the large intestine). Colon cancer is the second most common cancer diagnosed in the United States. , though the evidence isn't as strong. Among 28,000 women in Iowa, for example, those who lived where the water had the highest levels of DBPs had nearly double the risk of colon cancer of those who lived where the water had the lowest levels.(4) And cancer's not the only potential problem. In a 1998 study in northern California, pregnant women who lived where the tap water contained more than 75 parts per billion (ppb) of DBPs were nearly twice as likely to miscarry mis·car·ry v. To have a miscarriage; abort. as women who lived where the tap water contained less than 75 ppb, but only if they drank at least five glasses of water a day.(5) (The EPA's limit for DBPs is 100 ppb. It's scheduled to drop to 80 ppb beginning next year.) The link between DBPs and miscarriages is far from proven, though. In other areas of California, there didn't seem to be any association. Researchers have just begun a study of 950 pregnant women to see if drinking water is linked to miscarriages in North Carolina North Carolina, state in the SE United States. It is bordered by the Atlantic Ocean (E), South Carolina and Georgia (S), Tennessee (W), and Virginia (N). Facts and Figures Area, 52,586 sq mi (136,198 sq km). Pop. , Texas, and Virginia. 2 Turbidity turbidity /tur·bid·i·ty/ (ter-bid´i-te) cloudiness; disturbance of solids (sediment) in a solution, so that it is not clear.tur´bid Turbidity The cloudiness or lack of transparency of a solution. Is your tap water ever cloudy? That's a sign of turbidity. Unfortunately, most of the time it's not that obvious. Turbidity happens when particles of clay, silt, decaying plants, parasites, and other matter become suspended in the water. And it's not just a cosmetic or taste problem. Disease-causing microorganisms can cling to the particles and escape destruction by chlorination chlorination Public health Addition of chlorinated compounds to drinking water as disinfectants. Cf Ozonation. and other disinfection methods. Public water utilities are supposed to remove the particles when turbidity becomes excessive, but that's not always good enough. In 1993 in Philadelphia, for example, emergency room visits and hospital admissions for children with gastrointestinal illness increased by about ten percent whenever the turbidity of the city's public drinking water increased significantly (but remained below the legal limit and wasn't visible to consumers).(1) And about ten days after the spikes in turbidity, hospital admissions of the elderly for GI tract illnesses increased by nine percent.(2) "These and other studies suggest that ten percent of gastrointestinal illnesses in children and the elderly may be due to turbidity in ordinary tap water at levels that pass federal standards," says Joel Schwartz of the Harvard School of Public Health The Harvard School of Public Health is (colloquially, HSPH) is one of the professional graduate schools of Harvard University. Located in Longwood Area of the Boston, Massachusetts neighborhood of Mission Hill, next to Harvard Medical School and Cambridge, Massachusetts, , who led both studies. 3 Lead About 40 million Americans drink water with excess lead, and that water accounts for about 20 percent of our exposure to the toxic metal toxic metal Environment Any metal known to be toxic to humans–eg, antimony, arsenic, beryllium, bismuth, cadmium, lead, mercury, nickel. Cf Nontoxic metal. , according to the EPA. Lead builds up in the body over many years and can damage the brain, kidneys, and red blood cells Red blood cells Cells that carry hemoglobin (the molecule that transports oxygen) and help remove wastes from tissues throughout the body. Mentioned in: Bone Marrow Transplantation red blood cells . Water can pick up lead almost anywhere along the way from the plant to the tap--in holding tanks, underground pipes, or lead pipes and fixtures inside old buildings or homes, especially those built before the 1930s. Although the use of lead pipes and solder was banned in public water systems and household plumbing in the 1980s, they may sometimes still be used illegally, says the EPA. Fortunately, a coating of minerals builds up inside the pipes after a few years, which helps keep the lead from leaching into the water. 4 Arsenic According to "Arsenic in Drinking Water," a 1999 report by the National Academy of Sciences, the poison of choice of mystery writers can also cause cancer, heart disease, and perhaps diabetes. The EPA currently permits up to 50 ppb of arsenic in drinking water. But that standard was set 70 years ago, long before researchers discovered that the mineral can cause cancer. The World Health Organization recommends no more than 10 ppb. Congress has been pressuring the EPA for years to lower the arsenic limit. Arsenic-tainted water is most common in the Southwest and West. Some arsenic occurs naturally in soil, while some comes from industrial waste. 5 Parasites Cryptosporidium cryptosporidium (krĭp'tōspərĭd`ēəm), genus of protozoans having at least four species; they are waterborne parasites that cause the disease cryptosporidiosis. (crip-toe-spo-RID-eeum) is a parasite that lives in the intestines of humans and animals. When sewage or animal waste containing Cryptosporidium contaminates public water supplies, the results can be fatal. In 1993, for example, a breakdown in water sanitation in Milwaukee permitted Cryptosporidium to slip into the city's drinking water for a week. A hundred people (mainly those with weakened immune systems) died, and 400,000 suffered the diarrhea, stomach cramps, and fever that are the hallmarks of cryptosporidiosis Cryptosporidiosis Definition Cryptosporidiosis refers to infection by the sporeforming protozoan known as Cryptosporidia. Protozoa are a group of parasites that infect the human intestine, and include the better known Giardia. . Cryptosporidium is found in 65 to 97 percent of the nation's surface waters (rivers, lakes, and streams), according to the Centers for Disease Control and Prevention Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center. (CDC See Control Data, century date change and Back Orifice. CDC - Control Data Corporation ). People who drink treated surface water--which provides about half of our tap water--are more likely to be exposed to the parasite than people whose tap water comes from underground rivers, streams, and other sources, according to a recent study. What makes Cryptosporidium so tough to control is that it's small enough to pass through most filters (10,000 can fit on the period at the end of this sentence). And the parasite's hard outer shell protects it from the chlorine that's used to kill most microbes in water. Drinking-water regulations are designed to reduce--but not necessarily eliminate-Cryptosporidium, so even water systems that meet government standards may not be free of the parasite. What else might your drinking water contain? Everything from pesticides like atrazine atrazine a triazine herbicide; it is not poisonous at levels of intake likely to be encountered in agriculture. atrazine Toxicology A nonphytoestrogenic herbicide. See Phytoestrogen. to a possibly cancer-causing gasoline additive called MBTE MBTE Methyl Tertiary-Butyl Ether (fuel additive) . If that makes you nervous, here are three things you can do: * try to figure out what's coming out of your faucet (see "What's in Your Tap Water?" p. 4), * buy a filter (see "Filter This," p. 5.), or * switch to bottled water (see "Hitting the Bottle," p. 6). (1) Epidemiology 8: 615, 1997. (2) J. Epidem. Comm. health 54: 45, 2000. (3) Epidemiology 9: 126, 1998. (4) Amer. J. Pub. Health 87: 1168, 1997. (5) Epidemiology 9: 134, 1998. WHAT'S IN YOUR TAP WATER? The place to start is your Local public water utility. If you're a homeowner, you can find its address and phone number on your bill. If you rent, check the phone book. Many utilities also have Web sites. Ask for the latest "Consumer Confidence Report." That will tell you where your water comes from--whether it's surface water (from rivers or lakes), ground water (from underground rivers, streams, etc.), or some mix. It will also tell you whether your water exceeds the limits for any of 80 contaminants that are regulated by the Environmental Protection Agency (EPA). You should also ask for a printout of the levels of all 80 contaminants, since the EPA's limits for arsenic and disinfection byproducts are too high. If you get your water from a well, you'll need to get it tested yourself. Call the EPA Safe Drinking Water Hotline for information on how to obtain a list of certified labs (see "The Water Works"). Here's some of what to look for in the information you get about your water: * Total trihalomethanes (TTHMs) below 80 ppb. They're the most common disinfection byproducts. The EPA's current limit of 100 ppb (parts per billion) will drop to 80 ppb starting next year. * Turbidity below 0.5 NTU NTU - Network Termination Unit (nephelometric turbidity units). Keep in mind that outbreaks of gastrointestinal illness have occurred at levels as low as 0.2 NTU, which aren't enough to make the water look cloudy. * Lead below 15 ppb. Since any lead will probably come from the pipes inside your home, a clean bill of health a certificate from the proper authority that a ship is free from infection. See also: Clean from the water utility doesn't mean anything. If you want to know how much lead is in your water, you have to test it. Find a certified laboratory through the EPA Safe Drinking Water Hotline. Testing for lead is especially important for apartment dwellers in high-rise buildings, since the water may have to flow through a good deal of pipe before it reaches your faucet. * Arsenic below 10 ppb. Even the EPA admits that its limit (50 ppb) is too high. The World Health Organization's limit is 10 ppb. * Parasites. Water utilities and labs don't routinely test for Cryptosporidium, Giardia Giardia /Gi·ar·dia/ (je-ahr´de-ah) a genus of flagellate protozoa parasitic in the intestinal tract of humans and other animals, which may cause giardiasis; G. lam´blia (G. intestina´lis) is the species found in humans. , or other parasites because the analysis takes days to complete and can't distinguish live from dead parasites. FILTER THIS Filters vary widely in what they can remove, how much they cost, and how expensive they are to maintain. Pitchers or carafes that sit on a countertop or units that are mounted on your faucet can run anywhere from $100 to $75, while most under-the-sink units cost between $100 and $500. Don't forget to add $25 to $150 a year for replacement filters (not replacing used filter cartridges can make your water more contaminated). Here's how to choose a filter: 1. Check to see if the filter has been tested and certified by NSF International, a non-profit independent testing organization. A statement on the box or in the product information should list which contaminants the filter is certified to remove under which Standards. If a manufacturer hasn't paid an independent authority to test its filters, why take a chance on it? The Honeywell faucet-mounted Model NM-5000 box, for example, only says that the filter "has been tested against NSF International protocols...." That's not as solid a guarantee as a filter that "has been tested and certified by NSF International...." 2. Pick a Standard. NSF's tests use several "ANSI/NSF Standards" (ANSI (American National Standards Institute, New York, www.ansi.org) A membership organization founded in 1918 that coordinates the development of U.S. voluntary national standards in both the private and public sectors. It is the U.S. member body to ISO and IEC. stands for the American National Standards Institute See ANSI. (body, standard) American National Standards Institute - (ANSI) The private, non-profit organisation (501(c)3) responsible for approving US standards in many areas, including computers and communications. ANSI is a member of ISO. ). The two most common: * Standard 42 covers "aesthetic effects" like removing sulfate sulfate, chemical compound containing the sulfate (SO4) radical. Sulfates are salts or esters of sulfuric acid, H2SO4, formed by replacing one or both of the hydrogens with a metal (e.g., sodium) or a radical (e.g., ammonium or ethyl). , zinc, and other substances that affect "the water's taste, odor, or color, but that are not considered harmful," according to NSF NSF - National Science Foundation . * Standard 53 covers "health effects" like reducing Cryptosporidium, lead, turbidity, volatile organic chemicals (which include herbicides, pesticides, and trihalomethanes--the most common disinfection byproduct by·prod·uct or by-prod·uct n. 1. Something produced in the making of something else. 2. A secondary result; a side effect. Noun 1. ), and many other contaminants "that may pose a health risk if present in water in concentrations that exceed allowable levels." Other protocols cover ultraviolet treatment (Standard 55), reverse osmosis reverse osmosis n. The movement of a solvent in the opposite direction from osmosis in such a manner that the solvent moves from a solution of greater concentration through a membrane to a solution of lesser concentration. (Standard 58), and distillation (Standard 62). 3. Check the contaminants. A filter is only certified to remove the contaminants that are listed on the box or in the package information. For example, Brita's Standard Model Water Filtration Pitcher is certified to remove copper, lead, and mercury under Standard 53. Pur's Model FM-3000/37-500 faucet-mounted filter is certified to remove Cryptosporidium, Giardia, 2,4-D and atrazine (herbicides), lindane lindane: see insecticides. (a pesticide), asbestos, lead, mercury, and turbidity under the same Standard (see photo). That may mean that Brita didn't want to pay to have its filter certified for the other contaminants, or that the filter doesn't reduce their levels. 4. For more information. For a list of all the units that NSF has tested, and all the contaminants that they remove, send $5 to NSF International for a copy of "Water Wise--The Consumer's Guide to Safe Drinking Water" (see "The Water Works"). You can also try NSF's not-too-consumer-friendly Web site (www.nsf.org). It's updated more frequently than the book, but you can only search by company or specific contaminant (start by clicking on "Search for NSF Certified Products," then "Drinking Water Treatment Units"). RELATED ARTICLE: HITTING THE BOTTLE Is bottled water safer than tap water? There's no easy answer. It depends on where the bottled or tap water comes from, how (or if) it's been treated, and who's drinking it. Even so, the Centers for Disease Control and Prevention (CDC) " hasn't documented a microbial microbial pertaining to or emanating from a microbe. microbial digestion the breakdown of organic material, especially feedstuffs, by microbial organisms. outbreak of water-borne disease associated with bottled water in the United States," according to CDC epidemiologist Dennis Juranek. Bottled water comes with many names. Here's what some of them mean: * Spring water flows naturally to the earth's surface from underground formations. It makes up about 75 percent of the bottled water sold in the U.S. (the other 25 percent comes from municipal water supplies). Springs are supposed to be protected from pollution, according to industry guidelines and some state regulations. * Mineral water is spring water that naturally contains at least 250 milligrams of dissolved minerals (like magnesium and calcium) per liter. * Sparkling water is spring water that contains carbon dioxide carbon dioxide, chemical compound, CO2, a colorless, odorless, tasteless gas that is about one and one-half times as dense as air under ordinary conditions of temperature and pressure. gas. * Drinking water is water that has probably been drawn from a municipal system. If the water comes right out of the tap and into the bottle or jug, the label has to disclose which municipality it came from. But if the water receives additional treatment--if it is filtered or disinfected Disinfected Decreased the number of microorganisms on or in an object. Mentioned in: Isolation before being bottled--no disclosure is necessary. That's why you won't find any mention on bottles of Pepsico's Aquafina or Coca-Cola's Dasani that both originate from city water supplies. * Purified water has been treated with distillation, ion-exchange, reverse osmosis, or another similar process. * Distilled water comes from the steam of municipal water that has been boiled. The process gets rid of most contaminants, but not benzene, chlorine, and some other volatile organic chemicals (some companies filter them out separately). In an analysis by the non-profit Natural Resources Defense Council The Natural Resources Defense Council (NRDC) is a New York City-based, non-profit non-partisan international environmental advocacy group, with offices in Washington, D.C., San Francisco, Los Angeles, Chicago, and Beijing. Founded in 1970, NRDC today has 1. (NRDC NRDC Natural Resources Defense Council NRDC National Research and Development Centre (Institute of Education, London) NRDC National Realty & Development Corp. ), about a dozen of the 103 brands of bottled water tested between 1996 and 1999 exceeded federal, state, or industry guidelines.(1) Among the problem waters (which may or may not still be problems): * Six store brands of drinking or purified water (Lady Lee, Ralph's Private Selection, Publix, Randall's Deja Blue, Safeway, and Sahara) and two store brands of spring water (Safeway and Sahara) contained between 16 and 92 ppb of total trihalomethanes (TTHMs). * Four brands of mineral water (Apollinaris, Calistoga, Crystal Geyser, and Vittel) and three brands of spring water (Crystal Geyser, Palomaar, and Volvic) contained between 6 and 35 ppb of arsenic. Short of testing it yourself, there's no way to guarantee that your bottled water is free of contaminants. But you improve your chances if you stick to brands bottled by companies that are members of the International Bottled Water Association This article or section needs sources or references that appear in reliable, third-party publications. Alone, primary sources and sources affiliated with the subject of this article are not sufficient for an accurate encyclopedia article. (IBWA IBWA International Bottled Water Association IBWA Industry Based Workload Alignment ). Their plants are open to unannounced inspections by NSF International, an independent certification agency (see "The Water Works"). (1) "Bottled Water: Pure Drink or Pure Hype?" Natural Resources Defense Council, 1999. THE WATER WORKS The Environmental Protection Agency (EPA) Safe Drinking Water Hotline: (800) 426-4791. NSF International P.O. Box 130140 Ann Arbor, Michigan “Ann Arbor” redirects here. For other uses, see Ann Arbor (disambiguation). Ann Arbor is a city in the U.S. state of Michigan and the county seat of Washtenaw County. 48113-0140 Phone: (877) 867-3435 Fax: (734) 769-0109 Web: www.nsf.org International Bottled Water Association (IBWA) 1700 Diagonal Road, Suite 650 Alexandria, Virginia 22314 Phone: (703) 683-5213 Fax: (703) 683-4074 Information Hotline: (800)WATER II Web: www.bottledwater.org FOR MORE INFORMATION * Go to www.cspinet.org/nah/water * Check the Oct. 1999 Consumer Reports for a review of faucet-mounted and carafe water filters. RELATED ARTICLE: EXTRA PRECAUTIONS * To minimize your exposure to lead and other metals: Use only water from the cold-water tap for drinking, cooking, and making baby formula. Hot water is likely to contain more lead and other metals. If the tap hasn't been turned on for six hours or more, run the water until it gets as cold as it's going to get. That helps flush out any metals that may have accumulated. * To minimize your exposure to trihalomethanes and parasites: Boil your drinking water for at least one minute in an open pot, then let it cool down. That will vaporize va·por·ize v. To convert or be converted into a vapor. Vaporize To dissolve solid material or convert it into smoke or gas. any trihalomethanes and kill any Cryptosporidium or other parasites. If you don't use the water right away, refrigerate re·frig·er·ate tr.v. re·frig·er·at·ed, re·frig·er·at·ing, re·frig·er·ates 1. To cool or chill (a substance). 2. To preserve (food) by chilling. it. * If you have a severely weakened immune system: There's not enough evidence to say that you should avoid tap water, says the Centers for Disease Control and Prevention (CDC). But if you want to take "extra precautions," the CDC says co boil your tap water for at least a minute in an open pot or filter it with a system that is certified to reduce cysts (Cryptosporidium and Giardia) under ANSI/NSF Standard 53 (for a list, contact NSF International--see "The Water Works"). You can also drink bottled water that has been distilled or run through a reverse-osmosis filter. * If you drink only bottled water: Your teeth may not be getting enough fluoride, even if you use a fluoridated toothpaste. Tell your dentist, who may prescribe fluoride supplements, especially for children. (1) Epidemiology 8:615, 1997. (2) J. Epidem. Comm. Health 54:45, 2000. (3) Epidemiology 9:126, 1998. (4) Amer. J. Pub. Health 87:1168, 1997. (5) Epidemiology 9:134, 1998. |
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