If you've seen or read the recent reports about tests that found arsenic in apple juice, you may be wondering whether it could be dangerous to juice drinkers. The U.S. Food and Drug Administration issued a statement trying to reassure consumers that most of the arsenic in juices and other foods was of the so-called “organic” form, which the agency said was “essentially harmless.” But recent scientific evidence and public information issued by another federal agency cast doubt on that conclusion.
Concerns about arsenic in juices heightened after Mehmet Oz, M.D., a heart surgeon and host of The Dr. Oz Show aired a segment announcing results of lab tests he commissioned that found 10 of three dozen apple juice samples tested contained total arsenic levels exceeding the 10 parts per billion (ppb) federal limit for total arsenic levels in public drinking water.
The Oz test results are just the latest of several tests for arsenic in juice conducted over the past three years. As we reported previously, tests by university researchers and other labs say they have detected levels of total arsenic in apple juices that were up to three to five times higher than the 10 ppb public drinking water limit set by the U.S. Environmental Protection Agency (EPA), which is a limit that the FDA imposes for bottled water. The FDA does not set such limits for arsenic in other beverages, though in a Sept. 18 letter to FDA Commissioner Margaret Hamburg, U.S. Sen. Charles Schumer has called upon the agency to do so.
As part of our continuing series of stories about contamination of food and consumer products with lead, cadmium and other heavy metals, we are currently investigating the risks posed by dietary exposures to arsenic and will be bringing you more information soon on this problem and what you can do to reduce your risks of exposure. Meanwhile, here are some facts to help cut through confusion about the types of arsenic you may be exposed to in what you eat and drink:
What exactly is arsenic?
Arsenic is a metalloid, meaning it shares properties of metals and non-metals. It can be found in rock and soil, with trace amounts in some areas and heavy concentrations in others. Keep in mind that “naturally occurring” arsenic does not translate to “harmless.” On the list of 275 hazardous substances at toxic waste sites, the federal Agency for Toxic Substances and Disease Registry ranks arsenic as number one, based on risks to people living around those sites.
When arsenic leaches from such rock formations into groundwater, it can contaminate water used for drinking and irrigating crops. But arsenic has also been used for many commercial purposes. For decades arsenic-containing insecticides were widely used in orchards, vineyards and cotton fields. Even though the use of lead arsenate insecticides was banned in the U.S. in the late 1980s, arsenic remains in the soil, so past use of those pesticides can lead to contamination of fruit now grown in those orchards. Concerns also have been raised about the possible continuing use of arsenical insecticides in other countries, including China, which now supplies the majority of apple concentrate used in the U.S.
Arsenic also has been an ingredient in a wood preservative, chromated copper arsenate (CCA), used in pressure-treated lumber commonly found in outdoor decks or children’s playground equipment. Though CCA was banned for virtually all U.S. residential use in 2003, it is still used industrially and can even contribute to arsenic in groundwater when recycled as mulch. Through all of these routes and more, arsenic can enter the food chain.
What’s the difference between organic and inorganic arsenic?
Arsenic can combine with other elements to create compounds that are divided into two forms: inorganic arsenic compounds and organic arsenic compounds. When used to describe arsenic, the word “organic” has nothing do with the term that appears on labeling for foods that meet USDA certified organic standards.
When arsenic binds to elements such as sulfur, oxygen and chlorine, it forms inorganic arsenic compounds. Inorganic arsenic is a known human carcinogen and is the form found in drinking water, lead-arsenate insecticides and CCA.
Organic arsenic compounds are formed when arsenic binds to molecules containing carbon. Fish can contain an organic form of arsenic called arsenobetaine, which is generally considered non-toxic to humans. But much less is known about the health effects in humans of other types of organic arsenic, and products containing them have raised enough concerns that they are no longer being sold. EPA in 2006 took steps to stop the use of herbicides containing organic arsenic because of concern about their potential to transform into more toxic inorganic arsenic in soil and then contaminate drinking water.
Isn’t organic arsenic “harmless”?
We believe that the FDA’s statement that “inorganic forms of arsenic are the harmful forms, while the organic forms of arsenic are essentially harmless” is oversimplified. The wide range of serious human health risks of inorganic arsenic exposure has been well documented, as it is the form that contaminates drinking water. But there is not sufficient evidence to describe organic arsenic as “harmless.” The educational material provided by the federal Agency for Toxic Substances and Disease Registry to educate physicians about arsenic’s health effects points out that while the type of organic arsenic found in seafood appears to have low toxicity, other varieties of organic arsenic compounds have been shown in animal studies to produce health effects similar to those caused by inorganic arsenic.
ATSDR’s Arsenic Fact Sheet states: “Almost nothing is known regarding health effects of organic arsenic compounds in humans.”
Which type of arsenic is found in juices?
The FDA said in its recent statement that most arsenic found in juices is of the organic form and therefore is less of a concern. However, scientific research suggests that inorganic arsenic can be found in significant, if not dominant, portions of the total arsenic levels detected in juices:
- A 2009 study by researchers at the University of Arizona looked at total and inorganic arsenic levels in apple and grape juice. The study indicated that of the seven apple juice or cider samples tested, approximately 65 percent or more of the total arsenic present was the inorganic form. For the four grape juice samples, approximately 55 percent or more of the arsenic found was the inorganic form. Most importantly, the amount of inorganic arsenic in several samples of these juices exceeded the 10 ppb federal standard for total arsenic allowed in drinking water.
- Data from a 2008 FDA document which tested samples from three lots of pear juice concentrate, which were subsequently recalled, showed inorganic arsenic represented from approximately 52 percent to 67 percent of the total arsenic detected. We would like to see the FDA release full results of its research in this area.