Vol. 8, No. 5
this issue in pdf-format)
In this issue:
Solving Water Quality Problems
by Thomas Glanville, ISU Extension Ag & Biosystems Engineering
Phone: 515-294-0463 - e-mail: firstname.lastname@example.org
Although the majority of private water systems in Iowa produce acceptable water quality, many Iowans living on farmsteads and rural acreages must cope with a variety of naturally occurring and man-made water quality problems. Some of these have potential to affect human or animal health, while others cause odors, undesirable flavors, staining, and scale deposits. In this article, we will focus on some of the more common health-related concerns.
Coliform bacteria and nitrate are the most common health-related pollutants in Iowa private water systems. About 30% of water samples submitted to the University of Iowa Hygienic Laboratory by rural homeowners contain unsafe levels of total coliform bacteria. Nitrate exceeds human health advisory levels in about 13% of the private well samples tested. Lead, copper, arsenic, and pesticides also are detected occasionally, but unsafe concentrations of these are much less common than for nitrate and bacteria.
Today’s market offers many types of water treatment technologies. Each is capable of removing certain types of health-related contaminants, but none are designed to remove all contaminants. To identify treatment devices that
will meet their needs, homeowners must first determine which contaminants, if any, are in their water. Once this has been accomplished, the search for treatment equipment can be narrowed to specific devices designed to handle these contaminants. Here are a few tips to help evaluate drinking water quality and identify appropriate treatment options.
Start with water testing
Don’t rely solely on your senses to warn of unsafe water quality. Water that looks clear and tastes good isn’t necessarily safe. Laboratory testing is the only reliable way to assess drinking water safety.
To assess drinking water safety, start by focusing on the most common health-related problems. Test for total coliform bacteria and nitrate once each year, preferably during late spring or early summer when these contaminants are most likely to show up in shallow or defective wells.
If your plumbing system contains lead or copper piping, or lead-based solder (used in copper piping systems prior to late the 1980s), consider testing for lead and copper at least once every five years. Just because you have copper or lead components in your plumbing system, however, doesn’t guarantee you'll find unsafe concentrations of these metals in your drinking water. Mineral and oxide coatings that form naturally on interior pipe walls often prevent metals from being released into the water. High water temperatures, low pH, or excessive water velocity (caused by piping that is too small) can erode these coatings, however, making metal contamination more likely.
Some labs provide interpretations along with their numeric water test results, but some do not. The table below provides U.S. Environmental Protection Agency (USEPA) guidelines for some of the more common health-related contaminants encountered in Iowa wells. A complete listing of water quality standards is too lengthy to publish here, but the most recent listing of primary (health-related) drinking water standards mandated by the Federal Safe Drinking Water Act can be found on the World-Wide Web at http:// www.epa.gov/safewater/mcl.html.
Narrowing your treatment options
Once you know which pollutants are causing your water quality problem, and the extent of removal needed to meet drinking water standards, you are ready to begin your search for appropriate treatment equipment. Here are a few terms and tips to remember as you talk with equipment vendors.
Some health-related metals and chemicals can be removed from drinking water using reverse osmosis, activated carbon, or distillation. Reverse osmosis uses a membrane type of filter module that allows water molecules to pass through it, while restricting passage of pollutant molecules that are much larger than water or that are highly charged. Activated carbon filters are canisters filled with highly porous heat-treated charcoal that is capable of adsorbing certain types of gases and organic chemicals. Distillation uses heat to produce steam, thereby separating water from those contaminants that do not vaporize at temperatures near the boiling point of water. The steam is cooled and recondensed.
Iowa has a special law designed to provide Iowan’s with performance data for health-related drinking water treatment devices. This law requires all water treatment devices that are claimed to remove health–related contaminants from drinking water to be tested according to state-approved procedures. Furthermore, vendors of these treatment systems are required provide potential purchasers or renters with a performance data sheet that identifies the specific health-related contaminants each model is claimed to remove, and the percentage of removal achieved during testing.
Note that this law does NOT specify minimum equipment performance. It simply requires that potential buyers or renters be informed of the performance. It’s up to you to compare the performance of various brands and models to determine which offers the best removal. Equipment vendors are not required to provide performance data sheets for devices not claimed to remove health-related contaminants. For further information on Iowa’s law regulating the sale of residential drinking water treatment equipment, contact the Iowa Department of Public Health.
Biological contaminants that enter a water supply can grow and multiply inside pipes or water filters. Use of disinfecting chemicals, like chlorine or ozone, is the most effective way to control system-wide biological contamination since these chemicals are carried throughout the system to
locations where bacteria may reside. Ultraviolet (UV) light also is an effective disinfecting agent, and one that introduces no chemical flavors that some find e. Remember, however, that method of disinfection kills only those bacteria exposed to the UV light as water flows through the device. Unlike chlorine or ozone, UV treatment provides no chemical residual to combat biological contaminants that enter the system or grow at locations downstream of the treatment unit. Devices advertised to control health-related biological contaminants also must comply with the requirements of Iowa’s residential drinking water treatment equipment law.
For more information on testing and treating drinking water for health-related contaminants, contact your county sanitarian or public health nurse, a commercial water testing laboratory that serves your area, the University of Iowa Hygienic Laboratory (319-335-4500), or the Iowa Department of Public Health (515-281-5787). Additional ISU Extension information on health-related drinking water issues includes three 20-minute tapes and viewers guides in the Quality Water videotape series ("Manmade Chemicals" tape # 75706, guide # AE 3062; "Nitrate" tape # 75705, guide # AE 3061; and "Coliform Bacteria" tape # 75704, guide # AE 3060). ISU publication AEN-152,Diagnosing & Solving Common Water Quality Problems, may also be helpful. All ISU publications listed here can be downloaded from the World Wide Web at: http://www.abe.iastate.edu/water.htm.
|Plant Veggies for Health!|
Pat Anderson, ISU Extension FS/Nutrition
Phone: 712-482-6449 - e-mail: email@example.com
Garden vegetables not only add wonderful taste to family meals, they can also provide awesome health benefits. We have, of course, known about the benefits of the vitamins and minerals provided by vegetables for some time, but, through research, we are learning about health benefits of other components of these foods.
What should you plant for some of the good things in vegetables?
Plant lots of tomatoes and some watermelon: The red color of tomatoes and watermelons comes from lycopene, a member of the carotenoid family. Recent research suggests that lycopene may help prevent cancers, including cancers of the prostate, skin, breast, lung, cervix, bladder and digestive tract.
The evidence for lycopene comes from population studies that suggest people who eat lots of lycopene rich foods have lower rates of the cancers listed above.
Plant lots of tomatoes so you can either can, cook, or freeze them. Lycopene is more available in cooked tomatoes than in fresh tomatoes. In fact, cooked tomato products provide two to eight times as much lycopene as fresh tomatoes. Deep red tomatoes that are vine ripened also have more lycopene than pale tomatoes and those grown in your garden will have more than those that are grown in greenhouses.
Plant spinach and broccoli. Start an asparagus bed: These folate-rich foods may protect against colon and rectal cancers. Folate also helps lower homocysteine levels in your blood, which reduces risk for cardiovascular disease.
Folate provides protection against cancer by playing a role in DNA repair. When DNA damage occurs and there is a deficiency of folate the damage can lead to cancer. (Dried beans, lentils and orange juice are also sources of folate.)
Plant sweet corn, collards, kale, and spinach: These vegetables contain lutein and zeaxanthin which have been shown to delay development of cataracts.
Plant eggplant: Eat the whole eggplant because it is the skin that contains terpenes and flavonoids. Terpenes help lower cholesterol and flavonoids may help lower your risk of heart disease and stroke.
Plant and eat a wide variety of colors: A recent book on nutrition encourages people to "color their diet" with a wide variety of colors to get the health benefits of fruits and vegetables. Experts believe we need to eat more than the minimum five servings a day (a combination of three vegetables and two fruits) to get all the health benefits provided by these foods.
To keep phytochemicals (healthful plant chemicals) at maximum levels in your blood, produce needs to be eaten throughout the day. Research studies show that blood levels of phytochemicals drop to suboptimal levels within two to three hours of eating produce.
The DASH (Dietary Approaches to Stop Hypertension) eating plan to lower blood pressure has shown convincingly that a low-fat diet rich in lowfat dairy foods (two to three servings daily) and rich in fruits and vegetables substantially lowers blood pressure in people with or without high blood pressure. The DASH eating plan does this without sodium restriction or the use of drugs. For someone who eats about 2,000 calories a day the DASH plan recommends four to five vegetable servings (along with four to five fruit servings) daily.
Acreage Living is published monthly. For more information,
local county ISU Extension Office.
Editor: Shawn Shouse, ISU Extension FS/Ag Engineering, SW Area Extension, 53020 Hitchcock Avenue, Lewis, Iowa, 51544, Ph: 712/769-2600
Layout & Design: Paulette Cambridge, Office Assistant, SW Area Extension, 53020 Hitchcock Avenue, Lewis, Iowa 51544, Ph: 712/769-2600
...and justice for all.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Many materials can be made available in alternative formats for ADA clients. To file a complaint of discrimination, write USDA, Office of Civil Rights, Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington, DC 20250-9410 or call 202-720-5964.