Where you are in the Sustainable Community AHD process:
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Back to the Water Page
How to use this page: This is an indicator page. Examine this page for detail on the indicator and use that information to establish a metric for the indication of water quality. This is the final step in examining a sustainable community for its environmental attributes, water sub-attributes, and finally a water indicator. After completing this page, please go back and review other indicators and see discern metrics and weights for the AHD process.
Why is Arsenic an indicator of Water Quality?
Arsenic is one of the most prevalent contaminants of health concern in drinking water, and is present in the tap water of over 12 million Americans at a concentration above 10 ppb. Studies have linked long-term exposure to arsenic in drinking water to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate. Non-cancer effects of ingesting arsenic include cardiovascular, pulmonary, immunological, neurological, and endocrine (e.g., diabetes) effects.
Low-arsenic sources such as rain water and treated surface water may be available and appropriate in some circumstances where groundwater is contaminated. If low arsenic water is not available, it is necessary to remove arsenic from drinking-water. Technology to remove arsenic from piped water is costly and requires technical expertise. It is often not applicable in the rural areas, and sometimes not applicable in urban areas either. There are no technologies that have been proven to be successful in removing arsenic at the points of water collection (pumps, springs, wells, etc…). There is research being done on treating household water for arsenic, but the technologies are few and need to be specifically tailored for every setting.
What influences Arsenic levels in the Water?
Arsenic can get into drinking water through pesticide run-off, dissolution
of natural mineral deposits, industrial releases, improperly disposed chemicals, or atmospheric deposition.
What are the health effects to Arsenic exposure?
Prolonged Arsenic ingestion is known to cause skin cancer, and has been linked with increased risk for cancer of the lung, bladder, prostate, colon, and kidney. Arsenic has also been associated with diseases of the arteries, arterioles, and capillaries; exposure has also been associated with cardiac disease, diabetes mellitus, and cerebrovascular disease. Arsenic has been linked with damage to the immune system, affecting a person's ability to fight disease. Some individuals are more susceptible to the effects of arsenic exposure. Particular "at risk" groups include: children, older adults, and persons suffering from Hepatitis B, protein
deficiency, or malnutrition. Immediate symptoms of chronic arsenic exposure include vomiting, abdominal pain, and bloody diarrhea. Arsenic contamination of ground water is a global problem. It has been found in many countries, including Argentina, Bangladesh, Chile, China, India, Mexico, Thailand and the United States of America. At least 100,000 cases of debilitating skin lesions caused by arsenic are believed to have occurred in Bangladesh. Inorganic arsenic is a documented human carcinogen. Low arsenic water is only needed for drinking and cooking. Arsenic-rich water can be used safely for laundry and bathing.
What level of Arsenic is acceptable for a sustainable community?
EPA established an arsenic standard of 50 ppb in 1975, based on a Public Health Service standard originally established in 1942, and before arsenic was known to cause cancer. In January, 2001, after 25 years of public comment and debate, millions of dollars in research, and at least three missed statutory deadlines, the EPA lowered the standard to 10 parts per billion. Then on March 20, 2001, the Bush administration withdrew the EPA's recently revised standard of 10 ppb.
The National Academy of Sciences found in its 1999 report, Arsenic in Drinking Water, that:
- The 1942 arsenic standard, which was in place at the time, "does not achieve EPA's goal for public health protection."
- Drinking water at the 50 ppb standard "could easily" result in one in 100 persons getting cancer.
- That's a cancer risk 10,000 times higher than EPA allows for contaminants in food, and 100 times higher than EPA has ever allowed for tap water contaminants.
- The Academy recommended that the standard be lowered "as promptly as possible.
- The new 10 ppb standard is identical to the one adopted several years ago by the European Union and the World Health Organization
However, many studies have indicated that low levels of arsenic, even levels lower than 10 ppb may pose a serious health threat. The new standard is a step in the right direction but we may need to do better in the future in order to truly protect public health.
Where to go now that you
have reviewed an indicator:
Now that you have reviewed an indicator you should
create a metric (see
Step 4 of the
Analytical Hierarchy Processes) that indicates the importance of
this indicator in your decision process. Keep this step in mind as
you go through one of the other indicators below. Once you have
chosen a metric for each of your indicators, you should decide how
they collectively measure the sustainability of water by weighting
each indicator (see
Step 5 of the
Analytical Hierarchy Process). These will be applied in an
Step 6 of the Analytical Hierarchy Process) to give you the
final measurement for Water and Sustainability.