What is arsenic?
Arsenic occurs naturally in the environment, being the twentieth most common element in the Earth's crust. Arsenic is also the twelfth most common element in the human body. Arsenic is added to the environment by weathering of rocks, burning of fossil fuels, smelting of ores and manufacturing. It is widely distributed in nature and is mainly transported in the environment by water.
How might I be exposed to arsenic ?
For most people, the most significant route of exposure to arsenic is through food. It is a normal component of the diet. Studies by the Food and Drug Administration (FDA) have found that fish and seafood are higher in arsenic content than any other foods and account for the largest contribution to total arsenic intake in the typical adult diet.
Arsenic concentrations are generally highest in groundwater. Surface water concentrations, although generally low, also may be at levels of regulatory concern. Natural ore deposits of arsenopyrite (are-seen-oh-pie-right), a gold bearing mineral, may yield arsenic to ground water under anaerobic (ann-ah-robe-ick) (no oxygen) conditions.
How can arsenic affect my health?
Evidence exists that long-term exposure to high arsenic levels increases the risk of cancer. When exposure is by ingestion, the clearest effect is increased risk of skin cancer. Evidence also exists that the risk of internal cancer (liver, lung, bladder, and kidney) is also increased through ingestion. Ingestion of drinking water can be a source of arsenic exposure. Several national surveys of drinking water systems have found arsenic in 3-39 percent of all samples averaging less than 10 ppb. Arsenic is also a teratogen (tuh-rat-ah-gin) that is, an agent that is capable of crossing the placental membrane and into the metabolic system of the fetus during the first three months of pregnancy that induces abnormalities in a developing fetus.The actual toxicity of arsenic to humans varies depending on such factors as general health and diet. Arsenic is a cumulative substance, which slowly passes out of the body through the hair, fingernails and toenails.
The level of arsenic allowed in drinking water has been set by the State of Alaska Department of Environmental Conservation (ADEC) at 0.05 mg/l (milligrams per liter) or 50 ppb (parts per billion). At the present time the University of Alaska drinking water has only 8 ppb of arsenic present and we are working diligently on improving treatment methods which will reduce the level to below 1 ppb and aiming for a goal of having 0.00 ppb.
Arsenic can be removed from water by a number of available technologies, the choice of which depends on the amount of water to be treated, the amount of arsenic present, and the presence of other contaminants. At low concentrations in water with few other contaminants present, such as the UAF drinking water, a simple home sized system approved by ADEC is available. The "arsenic filter", an activated alumina filter originally designed for fluoride removal, was extensively tested by the Environmental Protection Agency (EPA) with the cooperation of the ADEC, with follow up testing in homes in Fairbanks, Alaska by Northern Testing Laboratories, Inc. The activated alumina filter requires no electricity or chemicals, and operates at a very high efficiency, removing nearly all of the arsenic. A quality assurance monitoring program should be followed which will verify the performance of the filter and is useful to estimate the remaining useful life of the filter for the homeowner. Another effective arsenic removal treatment technology is reverse osmosis.