NAME: Kandiah Sivarajah
TITLE: State toxicologist/public health toxicologist
COMPANY: Pennsylvania Department of Health
YEARS IN FIELD: 35
Q: What is arsenic and why would it show up in food, such as in the recent studies about arsenic in apple juice?
A: Arsenic is a naturally occurring element in the earth’s crust and is widespread in the environment. It has no smell or distinctive taste. Since arsenic is an element, it persists in the environment and does not break down. Arsenic compounds are found in two different forms in nature, inorganic and organic.
Arsenic may show up in food in many ways:
- Food that is prepared using arsenic-containing water.
- Plants may accumulate arsenic by root uptake from arsenic in the soil or by absorption of airborne arsenic deposited on the leaves.
- Plants that are treated with pesticides which may contain arsenic residues.
- Animals that drink arsenic-containing water and eat contaminated feed may concentrate arsenic in their organs, including meat.
- Some fresh water and marine organisms (e.g. fish, clams, crabs, lobster) can accumulate arsenic in their bodies from the environment.
Q: What happens to arsenic once it is ingested? How does it affect someone’s health? Does the type of arsenic consumed make a difference?
A: Following ingestion, arsenic is absorbed through the gut, enters the blood stream and is then widely distributed throughout the body. Most tissues rapidly clear arsenic except for skin, hair and nails. Within two to four weeks after exposure, most of the arsenic remaining in the body is found in the skin, hair and nails, and to a lesser extent, in bones and teeth.
Exposure to low levels of arsenic can cause nausea and vomiting, decreased production of red and white blood cells, abnormal heart rhythm, damage to blood vessels, and a sensation of “pins and needles” in hands and feet. Ingesting low levels of inorganic arsenic for a long time can cause a darkening of the skin and the appearance of small “corns” or “warts” on the palms, soles and trunk of the body. Ingesting high levels of arsenic can be fatal.
The toxicity of arsenic compounds can vary greatly. In general, inorganic arsenic is more toxic than organic arsenic.
The U.S. Department of Health and Human Services and the U.S. Environmental Protection Agency have determined that inorganic arsenic is a known human carcinogen.
Several studies have shown that ingestion of inorganic arsenic can increase the risk of skin cancer and tumors of the bladder, kidney, liver, and lungs.
Q: Is there a standard for the amount of arsenic that is safe to consume?
A: The U.S. Food and Drug Administration has established tolerance levels for arsenic in meat and organs of animals treated with veterinary drugs. These permissible levels range from 0.5 parts per million (ppm) in eggs and uncooked edible chickens and turkey parts to 2 ppm in certain uncooked edible pork products. The EPA has set a limit of 10 parts per billion or 10 g/L for arsenic in drinking water.
Q: Is there a test to determine if someone has been exposed to arsenic? What does it show?
A: There are tests available to measure arsenic in blood, urine, hair and fingernails. Measurement of arsenic in urine is the most reliable test for arsenic exposure that has occurred within the previous several days. Generally, most tests measure the total amount of arsenic in the urine. This can sometimes be misleading, because the nonharmful forms of arsenic in fish and shellfish can produce a high reading even if there has been no exposure to a toxic form of arsenic. Therefore, laboratories sometimes use a test that separate “fish arsenic” from other forms.
Since most arsenic leaves the body within a few days, analysis of urine cannot determine if a person was exposed to arsenic in the past. Hair or fingernails tests can tell if people have been exposed to high levels of arsenic over the past several months, but these tests are not very useful in detecting low-level exposures. If high levels of arsenic are detected in hair or fingernails, it means that exposure has occurred. But without more information about when a person was exposed and for how long, it is usually not possible to predict whether any harmful health effects will occur.
Q: What should consumers do if they are concerned about taking in too much arsenic?
A: Contact your health care provider for evaluation and assessment. If your health care provider believes you are ill due to arsenic then it may be appropriate to be tested for arsenic to document exposure. Efforts would then focus on identifying and eliminating sources of arsenic exposure.
Interview conducted via email by The Patriot-News staff.