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Sulfate is an inorganic contaminant so carbon based filters will not remove it. Sulfer is dificult to remove from water so I would suggest using a local water treatment company. Below is an article I thought you might find interesting about the subject. Please also see this web site as well it is the best one I have seen on the subject http://www.ianr.unl.edu/PUBS/water/g1275.htm
The US Environmental Protection Agency (EPA) may rule sulfate should not become a regulated drinking water contaminant after a study found sulfate does not appear to cause intestinal distress as previously suspected.
Sulfate is a substance that occurs naturally in drinking water. Health concerns regarding sulfate in drinking water have been raised because of reports that diarrhea may be associated with the ingestion of water containing high levels of sulfate.
An estimated six million people in the United States receive drinking water with high sulfate levels. Creating a maximum contaminant level (MCL) for sulfate would have been good for the point-of-use/point-of-entry (POU/POE) industry.
While a final decision whether the EPA should set an MCL for sulfate will not be made until August 2001, a recently released report by the EPA and the Centers for Disease Control and Prevention reduces overall concern about sulfate.
The bottom line: After an extensive review, EPA’s analysis found there was not a significant association between acute exposure to sodium sulfate in water — up to 1,200 milligrams per liter (mg/L) — and reports of diarrhea among adults.
EPA officials were particularly interested in groups within the general population that may be at greater risk from the laxative effects of sulfate when they experience an abrupt change from drinking water with low sulfate concentrations to drinking water with high sulfate concentrations.
As a result of the study, EPA officials says they may consider taking sulfate off the list of possible substances that need to be regulated for an MCL.
“We will be evaluating it in the future to see if other experts are in agreement,” says EPA groundwater specialist Jennifer Wu.
Impact on small systems and dealers
Sulfate is one of 50 chemical and 10 microbiological substances included on EPA’s contaminant candidate list.
Sulfate in drinking water currently has a secondary MCL of 250 mg/L, based on aesthetic effects. While not federally enforceable, the regulation provides a guideline for states and public water systems.
If the determination is made to regulate, the EPA must propose the MCL by August 2003 and issue a final rule by February 2005.
Setting an enforceable MCL for sulfate would have a significant impact on small system operators. The EPA estimates nearly 2,000 small water systems in the US have sulfate levels higher than 500 mg/L. These public water systems would have to install treatment systems to comply.
EPA official Irene Dooley says treatments such as reverse osmosis and ion exchange are possible, but it could be costly to require that all public water systems meet a level of 500 mg/L.
South Dakota did an analysis of the water systems that exceed 500 mg/L and estimated that it would cost $60 million to lower the sulfate levels of the 110 affected systems in the state to 500 mg/L.
South Dakota systems would likely chose to convert to using surface water sources for drinking water rather than to remove sulfate from groundwater.
Michael Baker of the South Dakota Department of Environment and Natural Resources says there is a relationship between sulfate content and the use of water for cooking, drinking, coffee. In areas where there is high levels of sulfate, people can choose to purchase bottled water or install reverse osmosis systems in their homes.
If the EPA adopts an MCL for sulfate, it would give water treatment dealers a good angle to sell POU/POE equipment. Until now, selling equipment to deal with sulfate has been largely based on aesthetics. An MCL based on health effects would give dealers a selling tool.
Not everyone is convinced a single study will end the debate. Existing literature supports issuing health advisories, especially for infants, that sulfate levels greater than 500 mg/L may have negative health effects.
Dr. Carl Shy of the University of North Carolina at Chapel Hill, School of Public Health, a health expert who facilitated an EPA discussion group on sulfate, says no one study can provide a dose-response relationship for sulfate.
Shy says other studies may be necessary, but that the review panel concluded there was not sufficient evidence on adverse health effects for sulfates to recommend a specific standard or MCL for sulfates in drinking water.
Meanwhile, water treatment experts say sulfates need to be regulated. “I am not surprised by anything the medical community comes up with these days,” says Gary Schreiber of the Purolite Co., Bala Cynwyd, PA. “We have been told, in the past, that sulfates combine with other ions and cause a variety of health problems. Now they don’t, according to the [study]. I believe an MCL for sulfate is needed.”
For now there does not appear to be much worry regarding sulfate’s health effects. However, the study only looked at sodium sulfate. Wu says study on magnesium sulfate may be required.
Study background
The Safe Drinking Water Act (SDWA), as amended in 1996, directed the EPA and the Centers for Disease Control and Prevention (CDC) to jointly conduct a study to establish a reliable dose-response relationship for the adverse human health effects from exposure to sulfate in drinking water, including the health effects that may be experienced by sensitive sub-populations, such as infants and travelers.
The purpose of the study was to examine the association between consumption of tap water containing high levels of sulfate and reports of osmotic diarrhea. The study was finished in February.
The EPA will be further evaluating the findings, analyzing all public comments on the documents, and reviewing any other pertinent information that could have a bearing on its decision of whether or not to regulate sulfate.
Study details
A population potentially sensitive to abrupt exposure to high levels of sulfate in drinking water is transient adults such as students and visitors who suddenly change drinking water sources from one that has little or no sulfate to one that is high in sulfate. The EPA gave volunteers a range of sulfate doses — up to 1,200 mg/L — to see if it caused stomach ailments.
CDC analyzed the number of bowel movements recorded each day by study participants and found there was no statistically significant differences in the bowel movements among the groups.
The debate on sulfate is not over. Several studies indicate there may be problems with high sulfate concentrations in wells.
Data from North Dakota on 248 private drinking water wells found that as the concentration of sulfate in these wells increased, more adults reported a laxative effect.
For example, for well water containing less than 200 mg/L sulfate, only 22 percent of consumers reported that their water had a laxative effect while water containing 1,000 mg/L concentrations of magnesium sulfate affected 62 percent of consumers.
Looking for more information on this topic? Please visit http://www.waternet.com and click on “Articles.” Use the following suggested keywords in an article search: groundwater, SDWA and sulfates.