Hydrogen Sulfides in Drinking Water
 |
Sulfates are a combination of sulfur and oxygen and are a part of naturally occurring minerals in some soil and rock formations that contain groundwater. The mineral dissolves over time and is released into groundwater. |
| Hydrogen sulfide gas also occurs naturally in some groundwater. It is formed from decomposing underground deposits of organic matter such as decaying plant material. It is found in deep or shallow wells and also can enter surface water through springs, although it quickly escapes to the atmosphere. Hydrogen sulfide often is present in wells drilled in shale or sandstone, or near coal or peat deposits or oil fields. Occasionally, a hot water heater is a source of hydrogen sulfide odor. The magnesium corrosion control rod present in many hot water heaters can chemically reduce naturally occurring sulfates to hydrogen sulfide. |
|
Indications of Sulfate and Hydrogen Sulfide
Hydrogen sulfide gas produces an offensive "rotten egg" or "sulfur water" odor and taste in the water. In some cases, the odor may be noticeable only when the water is initially turned on or when hot water is run. Heat forces the gas into the air which may cause the odor to be especially offensive in a shower. Occasionally, a hot water heater is a source of hydrogen sulfide odor. The magnesium corrosion control rod present in many hot water heaters can chemically reduce naturally occurring sulfates to hydrogen sulfide.
A nuisance associated with hydrogen sulfide includes its corrosiveness to metals such as iron, steel, copper and brass. It can tarnish silverware and discolor copper and brass utensils. Hydrogen sulfide also can cause yellow or black stains on kitchen and bathroom fixtures. Coffee, tea and other beverages made with water containing hydrogen sulfide may be discolored and the appearance and taste of cooked foods can be affected.
High concentrations of dissolved hydrogen sulfide also can foul the resin bed of an ion exchange water softener. When a hydrogen sulfide odor occurs in treated water (softened or filtered) and no hydrogen sulfide is detected in the non-treated water, it usually indicates the presence of some form of sulfate-reducing bacteria in the system. Water softeners provide a convenient environment for these bacteria to grow. A "salt-loving" bacteria, that uses sulfates as an energy source, may produce a black slime inside water softeners. Questions or concerns? Call us toll free at (888)623-2324 or email at Dennis@FloridasBestWater.com
Potential Health Effects
Sulfate
Sulfate may have a laxative effect that can lead to dehydration and is of special concern for infants. With time, people and young livestock will become acclimated to the sulfate and the symptoms disappear. Sulfur-oxidizing bacteria pose no known human health risk. The Maximum contaminate level is 250 mg/L.
Hydrogen Sulfide
 |
Hydrogen sulfide is flammable and poisonous. Usually it is not a health risk at concentrations present in household water, except in very high concentrations. While such concentrations are rare, hydrogen sulfide's presence in drinking water when released in confined areas has been known to cause nausea, illness and, in extreme cases, death. Water with hydrogen sulfide alone does not cause disease. In rare cases, however, hydrogen sulfide odor may be from sewage pollution which can contain disease-producing contaminants. Therefore, testing for bacterial contamination and Sulfate Reducing Bacteria is highly recommended. |
 |
Water TestingTesting for hydrogen sulfide should be done directly at the test sight in order to get the best possible test results in that hydrogen sulfide evaporates very quickly even in a sealed bottle. Click here for more information on Water testing |
Interpreting Sulfate and Hydrogen
Sulfide Test Results
Sulfate
The Environmental Protection Agency (EPA) standards for drinking water fall into two categories -- Primary Standards and Secondary Standards. Primary Standards are based on health considerations and are designed to protect people from three classes of toxic pollutants -- pathogens, radioactive elements and toxic chemicals. Secondary Standards are based on taste, odor, color, corrosivity, foaming and staining properties of water. Sulfate is classified under the secondary maximum contaminant level (SMCL) standards. The SMCL for sulfate in drinking water is 250 milligrams per liter (mg/l), sometimes expressed as 250 parts per million (ppm).
Hydrogen Sulfide
Although many impurities are regulated by Primary or Secondary Drinking Water Standards set by the EPA, hydrogen sulfide is not regulated because a concentration high enough to be a drinking water health hazard also makes the water unpalatable. The odor of water with as little as 0.5 ppm of hydrogen sulfide concentration is detectable by most people. Concentrations less than 1 ppm give the water a "musty" or "swampy" odor. A 1-2 ppm hydrogen sulfide concentration gives water a "rotten egg" odor and makes the water very corrosive to plumbing. Generally, hydrogen sulfide levels are less than 10 ppm, but have been reported as high as 50-75 ppm.
Options
If excessive sulfate or hydrogen sulfide is present in your water supply, you have three basic options:
- Obtain an alternate water supply, bottled water, or use some type of treatment to remove the impurity. The need for an alternate water supply or should be established before making an investment in treatment equipment or an alternate supply. Based the decision the results of a chemical analysis water, by a reputable laboratory, and after consulting with your physician to help you evaluate the level of risk. It may be possible to obtain a satisfactory alternate water supply by drilling a new well in a different location or a shallower or deeper well in a different aquifer.
- Another alternate source of water is bottled water that can be purchased in stores or direct from bottling companies. This alternative might be considered especially when the primary concern is water for food preparation and drinking but is not considered necessarily the greenest solution. Here is a Presentations Slide Show (you must click to advance each screen) on the environmental impact of bottled water use.
- The typical recommendation is the installation of a whole-house treatment system. This usually turns out to be the least expensive and best option for most people. Here in Florida and Ga. with our shallow wells, the logical answer is a good well treatment system. In the long run this usually equates as the best option based on price and water quality for the long term.
Hydrogen Sulfide Treatment
Several methods of removing hydrogen sulfide from water are available. The treatment method selected depends on many factors including the level of sulfate in the water, the amount of iron and manganese in the water, and if bacterial contamination also must be treated. The option you choose also depends on how much water you need to treat. Much of the above is thanks to Wilkes University in Pa.
Aeration
Aeration has been used for years in Florida. It requires a large holding tank, an extra well pump and and sprayers inside to disperse the hydrogen sulfide into the air..
Positives: It does remove hydrogen sulfide
Negatives: It smells bad, the second well pump running causes much more electrical usage, the sprayers clog and the float sticks and you have to clean and repair it. Requires maintenance on a regular basis
Chlorination
Chlorination is a process in which the well is first shocked with chlorine and then a chlorine feeder drops either pellets or liquid chlorine into the well at intervals.
Positives: It does remove iron
Negatives:
Requires the use of a hazardous material, chlorine Can be harmful to children, pets and others that come in contact with raw material Requires monitoring and refilling of chlorine container and monitoring with water testing. Requires the use of a carbon tank to remove the chlorine that is added before it reaches the house
Treatment with a Natursorb NS-7000 filtration unit
 |
Positives: Removes iron up to 8 ppm, removes hydrogen sulfide up to 7ppm, removes manganese, and can handle a wide range of ph.(acidity of water) The NS-7000 does not use any chemicals, nothing harmful to people or to pets, emits no smell, does not require an additional well pump, no cleaning required, does not require salt, does not require a Reverse Osmosis system. Negatives: YOU DON'T HAVE ONE YET! The NS-7000 is custom made for your well based on a current water test and not an off the shelf unit that might or might not do the job. In our many years in the water treatment business, we have seen technology radically change the way we have approached water treatment. The technology of 30 years ago did the job but did not do it nearly as efficiently as we can do it today. Think back to the technology we had 30 years ago compared to today. No computers, no cell phones, no ipods, no dvd, car engines that only lasted a third as long as they to today. Things have changed drastically and we have stayed with the times to bring you the most advanced well system on the market at any price.(ours is cheaper) Often the treatment for hydrogen sulfide is the same as for iron and manganese, for more information please visit the iron section. |
In Closing
Sulfates and hydrogen sulfide are both common nuisance contaminants. Although neither is usually a significant health hazard, sulfates can have a temporary laxative effect on humans and young livestock. Sulfates also may clog plumbing and stain clothing. Hydrogen sulfide produces an offensive "rotten egg" odor and taste in the water, especially when the water is heated.
Treatment options depend on the form and quantities in which sulfates and/or hydrogen sulfide occur in untreated water- Therefore, it is critical that a comprehensive water analysis be conducted.
We want you, our customers to know that if we can be of help we will be of help. All you have to do is call or email and we will be there to assist you whether you just need questions answered, a full water test or a system installed. We are here for you always. And remember the motto. “YOU SHOULD NEVER HAVE TO THINK ABOUT YOUR WATER!!”
Note: If the cause of the problem is associated with the presence of Iron Reducing Bacteria, Sulfate Reducing Bacteria, and elevated levels of hydrogen sulfide, iron, manganese and other problems. It is critical that the water be tested prior to selecting a treatment system.
