Understanding Arsenic in your Drinking Water
Arsenic Electronic Discharge Lamp
Arsenic in Your Drinking Water?
Here's some information I've put together to help folks better understand about arsenic in their drinking water. I think Hub Pages are a great place for me to share the information and fun facts I've learned over the years about drinking water. Hope you find it helpful and interesting!
Arsenic is a soft, semi-metallic element that is found naturally in our environment. It can be in widespread areas, or in geographically specific locations. We also see arsenic introduced through orchards, old cemeteries, treated lumber, and certain industrial processes such as glassware and electronic components production. The MCL, or maximum contaminant level had been set at 50 ppb (parts per billion) from 1975 until January, 22, 2001 when the new EPA (Environmental Protection Agency) level became 10 ppb. Why lower the level five-fold? That's a pretty big drop, when you consider that now all of the regulated water systems across the country now had to meet these new, more stringent standards. What did the EPA discover after studying arsenic to make them drop the level that much?
As far as contact goes, arsenic exposure should be limited. I try to remind myself of that whenever I spill some on my hands in the lab! Long term exposure to arsenic in drinking water has been linked to cancer of the bladder, lungs, skin, kidneys, liver, and prostate. Other non-carcinogenic effects may include cardiovascular, pulmonary, immunological, neurological, and endocrine (diabetes) disorders. Large doses of arsenic can be lethal and has been the poison - du jour for centuries! Who hasn't read a mystery or thriller where arsenic was the deadly agent involved?
Adopting the new, stricter standards will provide increased protection for over 54,000 community water systems - such are the types that serve small cities and towns, apartments, and mobile home parks. Also, over 20,000 systems that serve such institutions as schools, churches, and nursing homes also must have complied to the new regulations by January 23, 2006.
In the laboratory, we analyze arsenic from all parts of the state and country. We do find geographical hot-spots where arsenic turns up at higher levels. It is not uncommon to find levels well over 100 ppb in some areas. Arsenic is odorless and tasteless, so the only way for you to tell if your well or source water has arsenic in it is to have it analyzed by a laboratory certified for that parameter. To find a certified lab., you can check with your state health department or call the Safe Drinking Water Hotline at, 1-800-426-4791.
Arsenic can be removed from water, but we need to take a closer look at the element itself. Arsenic can come in two forms, or valences. One, is inorganic, the other organic. The EPA MCL of 10 ppb is based on total combined arsenic. One form, trivalent or AsIII is also known as arsenite. The other form, pentavalent, or AsV is also known as arsenate. Most manufacturers produce filters that will remove pentavalent arsenic as long as the starting level is less than 300 ppb. Speciation can be performed to determine which forms you have and in what proportions, but as you read further, it is not really necessary to speciate. Typically, the trivalent form is converted to pentavalent form using free chlorine or other similar oxidation chemical because AsV is easier to remove. As previously mentioned, have a certified lab give you the total arsenic number, then let a qualified and experienced treatment professional take care of the filtration.
For more tips and helpful hints, go to http://www.aquacheck-vt.com/ and check out the Water Wisdom section. You can also sign up for our free newsletter there!
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