What Is Arsenic and Why Is It in Food?

glasses with poison labels including arsenic, belladonna, and strychnine
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Arsenic is a poisonous chemical often used in herbicides and pesticides and is classified as a Class 1 carcinogen, meaning it is highly toxic to humans. Other Class 1 carcinogens include asbestos, formaldehyde, and hepatitis B and C viruses. According to the EPA, "arsenic has been linked to cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate." Arsenic is found in chicken and fish because of a contaminated water supply used in feeding and preparing meat for human consumption.

Arsenic Exposure

Arsenic exists not only in the bodies of animals used for foods such as chicken but also in the American water supply. Although some environmental exposure to arsenic may be unavoidable, as more and more Americans reduce their consumption of red meat, they are often replacing this with chicken and fish and thus exponentially increasing their consumption of arsenic at rates never before experienced. 

How to Test for Arsenic in Your Body: Blood, Urine, Hair, and Fingernails Samples

There are tests available to measure arsenic in your blood, urine, hair, and fingernails. The urine test is the most reliable test for arsenic exposure within the last few days. Tests on hair and fingernails can measure exposure to high levels of arsenic over the past 6 to 12 months. A blood sample is not a good indicator of arsenic exposure as inorganic arsenic has a short half-life of just 4 to 6 hours. If you fear you've been exposed to high levels of arsenic, you can purchase tests online or talk to your doctor about your concerns.

Symptoms of Arsenic Poisoning

Arsenic exposure is usually occupational or environmental but can result from deliberate poisoning. Symptoms usually start within 30 minutes to 2 hours of exposure. The symptoms that are associated with high levels of arsenic or arsenic poisoning are ambiguous and can be mistaken for other medical problems. Symptoms of acute arsenic poisoning include a severe headache, mild to severe nausea, vomiting, diarrhea, abdominal pain, hypotension, fever, hemolysis, seizures, and mental status changes.

Symptoms of chronic poisoning, also called arseniasis, are mostly insidious and nonspecific. The gastrointestinal tract, skin and central nervous system are usually involved. Nausea, epigastric pain, colic (abdominal pain), diarrhea, and paresthesias of the hands and feet can occur.

Preventing High Levels of Arsenic Exposure

Arsenic is a natural component found in the earth's crust. It is a heavy metal. There are different forms of arsenic and its toxicity is directly correlated by the type encountered. Arsenic comes in inorganic and organic forms. Inorganic arsenic is found in water and is highly toxic. Organic arsenic compounds, those found in seafood, is less harmful and not associated with arsenic poisoning. Arsenic can be absorbed into the skin, ingested or inhaled. The only way to prevent arsenic exposure is by protecting the water supply. According to the World Health Organization:

The most important action in affected communities is the prevention of further exposure to arsenic by the provision of a safe water supply for drinking, food preparation and irrigation of food crops.