When most people hear the word “arsenic,” they think of the organic, carbon-containing versions (such as monosodium methanearsonate and disodium methanearsonate), which are used as pesticides. For the most part however, organic arsenics have not been found to be detrimental to human health.
In their natural form, these semi-metallic elements are found in rocks, soil, and ground and surface water. In fact, there are more than 200 different types of arsenic sulfides and minerals; and organic arsenic is even in the atmosphere, particularly near metal processing industries such as mining operations and smelters.
Food, consumer products contain inorganic arsenic
The US Department of Health and Human Services’s Agency for Toxic Substances and Disease Registry has designated inorganic arsenic, which is formed when arsenic is combined with elements other than carbon, as a carcinogen. These cancer-causing types of arsenic are typically used during industrial processes.
For example, wood-product manufacturers use inorganic, chromated copper arsenate (CCA) in products such as residential decks and porches, picnic tables and playground play sets to ward off insects and to protect wood from rotting and from microbial contamination, such as mildew. Although the industry has been making an effort to discontinue using CCA, there are no federal regulations prohibiting it as an ingredient in consumer products.
Meanwhile, experts say that the most abundant source of inorganic arsenic is found in drinking water. It is also found in juices and other drinks that contain water as well as some foods, such as carrots and rice. This is because waste runoff from factories causes inorganic arsenic to get into drinking-water and food-irrigation systems. In addition to wood products, inorganic arsenics are used at plants that manufacture ammunition, metal adhesives, and lasers and semiconductors as well as at factories that process paper, paints and dyes, glass, textiles and leather products, and even some pharmaceuticals.
Up until 2011, the poultry industry used an arsenic-based animal drug — 3-Nitro (roxarsone) — to help prevent coccidiosis, an intestinal parasitic infection that occurs in chickens and other animals. However, similar organic, arsenic-based drugs are still used in the feeds given to food-producing poultry and swine.
Additionally, a form of inorganic arsenic is a component in cigarettes; and environmental studies have confirmed its presence in the indoor air of homes with residents who are smokers.
Cancer risk, other health problems
Studies have linked the ingestion of inorganic arsenic to bladder, kidney, liver, prostate, lung and skin cancers. Moreover, research has associated inorganic arsenic intake with reproductive and developmental toxicity as well as an increased risk for congenital heart disease.
Meanwhile, the US Environmental Protection Agency (EPA) allows public drinking water to contain 10 parts per billion (ppb) of inorganic arsenic but its presence has been documented at higher levels in rural water sources and personal wells. Still, the US Food and Drug Administration follows the EPA’s standard, allowing fruit juices and bottled water to contain 10 ppb of such inorganic arsenics as dimethylarsinic acid and monomethylarsonic acid.
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