Arsenic Drinking Water Groundwater Contamination and Water Testing

arsenic, groundwater, toxic metals, arsenates, arsenic testing private wells

Click on Map to See Full Scale - Arsenic concentrations in
Ground Water of the United States. (Source: USGS)

What is arsenic?

Arsenic is a semi-metal, a member of the nitrogen family. It occurs naturally in the earth and in the seas. It is odorless and tasteless. Arsenic is an element (As) that occurs in the earth’s crust-rock, soil, all natural sources of exposure, or can be traced to deep water brines used to produce oil and natural gas. Consumption of food and water are the major sources of arsenic exposure for the majority of US citizens. People may also be exposed from industrial sources, as arsenic is used in semiconductor manufacturing, petroleum refining, wood preservatives, animal feed additives, and herbicides.

Arsenic can combine with other elements to form inorganic and organic arsenicals. In general, inorganic derivatives are regarded as more toxic than the organic forms. While food contains both inorganic and organic arsenicals, primarily inorganic forms are present in water. Exposure to arsenic at high levels poses serious health effects as it is a known human carcinogen. In addition, it has been reported to affect the vascular system in humans and has been associated with the development of diabetes.

As compared to the Western part of the United States, it is relatively rare contaminant in Pennsylvania groundwater supplies. A recent survey by the U.S Geological Survey (USGS) found that arsenic exceeded 5 ppb in 5% of wells in Pennsylvania.

What is the measurement of arsenic?

On June 22, 2000 EPA proposed a 5 ppb standard for arsenic. EPA requested comment on 10 ppb, 5 ppb and 3 ppb. Based on the comments, EPA is implementing a 10 ppb standard for arsenic. This rule became effective on February 22, 2002 and systems must comply with the new 10 ppb standard is January 23, 2006. The Proposed Arsenic Rule, updated March 2002, can be found by visiting the EPA Website.

What are the symptoms of arsenic poisoning?

Observable symptoms of arsenic poisoning are: thickening and discoloration of the skin, stomach pain, nausea, vomiting, diarrhea, numbness in hands and feet, partial paralysis, and blindness.

How does arsenic enter my private water system?

It is widely thought that naturally occurring arsenic dissolves out of certain rock formations when ground water levels drop significantly. Surface arsenic-related pollutants enter the ground water system by gradually moving with the flow of ground water from rains, melting of snow, etc. Either way, ongoing testing for arsenic is an important strategy by the private water system owner to safeguard the health and well being of their family.

Is my private well at risk?

Like many contaminants in drinking water, the element is potentially hazardous at levels or concentrations that do not impart a noticeable taste, odor, or appearance to the water. Your best course of action is to get you water tested and compile as much information as possible about your water supply source, well construction, surrounding land-use, and local geology. If you do have an arsenic problem, there are water treatment technologies available now that can reduce or even remove arsenic from your drinking water. Note: Do not just test your water for Arsenic because there may be other primary and secondary drinking water standards that are elevated or that may interfere with the proposed remediation system.

1. Get your Water Tested and encourage your neighbors to do the same- Arsenic Analysis Added to Homeowner Outreach Program - Effective 4/10/2003..- The Option 1 with Arsenic or the Option 4 Package.
2. Compile information on the types and location of hazardous waste and industrial sites in your area.
3. Contact your States Environmental Protection Division.

What types of treatment devices will make my water safe for consumption?

The following water treatment technologies are effective in reducing arsenic from drinking water:

1.Activated alumina filters
2.Anion exchange
3.Distillation
4.Reverse Osmosis
5.Nanofiltration
6. Iron Oxide Filters

Pretreatment may be needed in some cases to ensure acceptable treatment by the primary unit. Also, as a safeguard against organic arsenic, granular activated carbon filtration should be added. Some of the treatment technologies may not be amenable to point-of-entry, whole house treatments. In these cases, point-of-use units may be the best option. Periodic testing should be maintained after the treatment system is in place to ensure objectives are being met.

Note: In many cases, arsenic will be removed when iron is removed through an oxidation process.

New Hampshire:
http://www.dhhs.state.nh.us/DHHS/HLTHRISKASSESS/LIBRARY/Fact+Sheet/contaminants.htm .

Maine: http://www.maine.gov/dhhs/eohp/wells/asbrochure.shtml

Vermont: http://healthvermont.gov/enviro/water/arsenic.pdf

Massachusetts: http://www.mass.gov/dep/water/drinking/arswell.htm

U.S. Environmental Protection Agency:
http://www.epa.gov/safewater/arsenic/basicinformation.html

Agency of Toxic Substances and Disease Registry:
http://www.atsdr.cdc.gov/arsenic/index.html