Arsenic is a natural element that can be found in rocks and soil, water, air, and in plants and animals. It can also be released into the environment from some agricultural and industrial sources.
Although it is sometimes found in its pure form as a steel grey metal, arsenic is usually part of chemical compounds. These compounds are divided into 2 groups:
Inorganic compounds - (arsenic combined with elements other than carbon):
These compounds are found in industry, in building products (such as some “pressure-treated” woods), and in arsenic-contaminated water.
This is the form of arsenic that tends to be more toxic and has been linked to cancer.
These compounds are found in industry, in building products (such as some “pressure-treated” woods), and in arsenic-contaminated water.
This is the form of arsenic that tends to be more toxic and has been linked to cancer.
Organic compounds - (arsenic combined with carbon and other elements):
These compounds are much less toxic than the inorganic arsenic compounds and are not thought to be linked to cancer.
These compounds are found in some foods, such as fish and shellfish.
These compounds are much less toxic than the inorganic arsenic compounds and are not thought to be linked to cancer.
These compounds are found in some foods, such as fish and shellfish.
How are people exposed to arsenic?
Arsenic occurs naturally in the environment, as well as being present in some man-made products.
We normally take in small amounts in the air we breathe, the water we drink, and the food we eat.
Most arsenic compounds have no smell or taste, so usually you can’t tell if arsenic is in your air, food, or water.
We normally take in small amounts in the air we breathe, the water we drink, and the food we eat.
Most arsenic compounds have no smell or taste, so usually you can’t tell if arsenic is in your air, food, or water.
People can also be exposed to higher levels of arsenic in some other ways. Very high doses have been used in murder or suicide attempts.
Some jobs may expose workers to high levels over long periods of time when they breathe in or swallow dust that contains arsenic compounds, but such exposures are now rare in the United States.
Some jobs may expose workers to high levels over long periods of time when they breathe in or swallow dust that contains arsenic compounds, but such exposures are now rare in the United States.
People who live near current or former industrial or agricultural sources of arsenic can be exposed to higher levels by inhaling fumes or eating contaminated food.
People can also take in higher levels of arsenic if they live in areas where arsenic levels are naturally high in the drinking water or if they eat a lot of rice or seafood (although the organic form found in seafood is likely to be much less harmful).
People can also take in higher levels of arsenic if they live in areas where arsenic levels are naturally high in the drinking water or if they eat a lot of rice or seafood (although the organic form found in seafood is likely to be much less harmful).
How is arsenic used?
Arsenic compounds have been used in many ways, including:
- As a preservative in pressure-treated lumber
- In pesticides
- As a preservative in animal hides
- As an additive to lead (such as in lead-acid batteries) and copper
- In some glass manufacturing
- As arsine gas to enhance electrical junctions in semiconductors
Although arsenic can be poisonous in higher doses, it has also been used in some medicines.
In the 1800s and early 1900s, arsenic was commonly used to treat diseases such as syphilis and psoriasis.
A form of arsenic is still used to treat an uncommon blood cancer known as acute promyelocytic leukemia.
In the 1800s and early 1900s, arsenic was commonly used to treat diseases such as syphilis and psoriasis.
A form of arsenic is still used to treat an uncommon blood cancer known as acute promyelocytic leukemia.
Arsenic occurs in large quantities in the earth's crust and in trace quantities in rocks, soil, water and air.
Exposure to high levels of arsenic can cause cancers and other disorders.
Boiling water contaminated with chemicals such as nitrates or toxic elements such as arsenic is a bad idea.
So there may be circumstances when re-boiling water is a problem this is really only a problem in a few rural areas where water quality isn't monitored.
Exposure to high levels of arsenic can cause cancers and other disorders.
Boiling water contaminated with chemicals such as nitrates or toxic elements such as arsenic is a bad idea.
So there may be circumstances when re-boiling water is a problem this is really only a problem in a few rural areas where water quality isn't monitored.
In food
For most people, food is the largest source of arsenic, although much of this is likely to be in the less dangerous, organic form.
The highest levels of arsenic (in all forms) in foods can be found in seafood, rice, rice cereal (and other rice products), mushrooms, and poultry, although many other foods can contain low levels of arsenic.
The highest levels of arsenic (in all forms) in foods can be found in seafood, rice, rice cereal (and other rice products), mushrooms, and poultry, although many other foods can contain low levels of arsenic.
Rice is of particular concern because it is a major part of the diet in many parts of the world.
It is also a major component of many of the cereals eaten by infants and young children. (Nearly all rice products have been found to contain at least some arsenic, although the levels can vary widely.)
It is also a major component of many of the cereals eaten by infants and young children. (Nearly all rice products have been found to contain at least some arsenic, although the levels can vary widely.)
In drinking water
Drinking water is an important and potentially controllable source of arsenic exposure.
In fact, drinking water is a major source of arsenic exposure in some parts of the world.
In parts of Taiwan, Japan, Bangladesh, and western South America, high levels of arsenic occur naturally in drinking water.
In fact, drinking water is a major source of arsenic exposure in some parts of the world.
In parts of Taiwan, Japan, Bangladesh, and western South America, high levels of arsenic occur naturally in drinking water.
Water in some areas of the United States, especially in the West, also naturally contains arsenic.
Most US areas with higher levels of arsenic in drinking water are rural communities.
Albuquerque, New Mexico, is the only urban area in the US with substantial natural arsenic levels in drinking water.
Most US areas with higher levels of arsenic in drinking water are rural communities.
Albuquerque, New Mexico, is the only urban area in the US with substantial natural arsenic levels in drinking water.
Arsenic levels tend to be higher in drinking water that comes from ground sources, such as wells, as opposed to water from surface sources, such as lakes or reservoirs.
Arsenic levels in public drinking water are regulated in the United States by the Environmental Protection Agency (EPA).
Since January 2006, the maximum level of arsenic allowed in US drinking water is 10 μg/L (micrograms per liter), or 10 ppb (parts per billion).
Since January 2006, the maximum level of arsenic allowed in US drinking water is 10 μg/L (micrograms per liter), or 10 ppb (parts per billion).
At work
Arsenic has not been produced in the United States since 1985, although it is imported from other countries.
In the past, workers in smelters and in plants that manufactured, packaged, or distributed products that contained arsenic had high exposures from breathing in arsenic fumes and dust.
In the past, workers in smelters and in plants that manufactured, packaged, or distributed products that contained arsenic had high exposures from breathing in arsenic fumes and dust.
Arsenic was a common ingredient in many pesticides and herbicides in the past. People who made, transported, applied, or worked around these products may have been exposed to higher levels of arsenic.
Inorganic arsenic compounds have not been used in pesticides in the US since 1993, and organic compounds have been phased out of pesticides (with one exception used on cotton plants) as of 2013.
Inorganic arsenic compounds have not been used in pesticides in the US since 1993, and organic compounds have been phased out of pesticides (with one exception used on cotton plants) as of 2013.
Today workplace exposure to arsenic can still occur in some occupations that use arsenic, such as copper or lead smelting, and wood treating. Regulations in place can help limit this workplace exposure.
In the community
Communities near previous or current agricultural or industrial sources may be exposed to arsenic.
Industrial buildings such as wood preservative and glass factories can contaminate nearby air, soil, and water.
Communities near smelters, or near farm fields or orchards where arsenic pesticides were used, may also have contaminated soil.
Burning fossil fuels (such as coal) and tobacco can also release small amounts of arsenic into the air.In pressure-treated wood
Chromated copper arsenate (CCA) is a chemical preservative that helps protect wood from rot and insects.
It was used to pressure-treat lumber that was used in some home foundations, decks, fences, playgrounds (play sets), and other structures for many decades.
In fact, starting in the 1970s, most of the wood used in residential settings was CCA-treated wood.
It was used to pressure-treat lumber that was used in some home foundations, decks, fences, playgrounds (play sets), and other structures for many decades.
In fact, starting in the 1970s, most of the wood used in residential settings was CCA-treated wood.
The use of CCA in pressure-treated lumber for most residential (home) uses was stopped at the end of 2003 (although it is still used for industrial purposes).
This was done because of concerns that some of the arsenic might leach out of the wood and enter the soil or be absorbed through the skin when the wood is touched.
Wood that is frequently touched by children, such as that found in some playground equipment, is a special concern.
This was done because of concerns that some of the arsenic might leach out of the wood and enter the soil or be absorbed through the skin when the wood is touched.
Wood that is frequently touched by children, such as that found in some playground equipment, is a special concern.
People can also be exposed to arsenic by breathing in sawdust from cut arsenic-preserved wood or by breathing the smoke from burning this wood.
Pressure-treated lumber for residential uses is now made with other compounds that do not contain arsenic.
However, any structures built from lumber that was pressure-treated before 2004 may still contain CCA. (For more information, see the section “How can I limit my exposure to arsenic?”)
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However, any structures built from lumber that was pressure-treated before 2004 may still contain CCA. (For more information, see the section “How can I limit my exposure to arsenic?”)
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