Consumer Reports discloses additional data from its arsenic tests

When Consumer Reports tested 88 samples of apple juice and grape juice for lead and arsenic, we not only measured levels of total arsenic, but we also conducted additional tests to identify what forms of arsenic were present or detected in those juice samples, which were purchased in August and September 2011 in New York, New Jersey, and Connecticut by Consumer Reports staffers.

Identifying the type of arsenic present in juices is important because the health risks posed by arsenic exposure depend in part on the specific type of arsenic you ingest. When arsenic binds to elements such as sulfur, oxygen and chlorine, it forms what are known as inorganic arsenic compounds. Inorganic arsenic is a known human carcinogen and it is the form found in drinking water and in lead-arsenate pesticides that were widely used for decades in orchards and vineyards. The majority of the arsenic we found in most juice samples we tested was inorganic.

The other form that arsenic takes is organic. When used to describe arsenic, the word "organic" has nothing to do with the term that appears on labeling for foods that meet USDA certified organic standards. Organic arsenic compounds are created when arsenic binds to molecules containing carbon. Fish can contain an organic form of arsenic called arsenobetaine, generally considered non-toxic to humans. But questions have been raised about the human health effects of other types of organic arsenic in foods, including juice.

In fact, the U.S. Food and Drug Administration has revised information provided on its website to include the following statement: "Some scientific studies have shown that two forms of organic arsenic found in apple juice could also be harmful, and because of this, the FDA counts these two forms of organic arsenic in with the overall content for inorganic arsenic."

The educational material provided by the federal Agency for Toxic Substances and Disease Registry to educate physicians about arsenic's health effects also points out that while the type of organic arsenic in seafood appears to have low toxicity, other organic arsenic compounds have been shown in animal studies to produce health effects similar to those caused by inorganic arsenic.

To add to the growing body of scientific evidence on the specific types of arsenic that may be found in juices, Consumer Reports is providing complete data that shows the levels of two species of inorganic arsenic and three species of organic arsenic detected in our tests of the juice samples, as detailed in this downloadable PDF.

As we reported previously, the total arsenic levels (organic and inorganic combined) we detected ranged up to 13.9 parts per billion (ppb) in apple juice samples we tested and up to 24.7 ppb in grape juice samples, with 10 percent of samples exceeding federal drinking water limits of 10 ppb for total arsenic.

The additional data we have displayed in the expanded version of the test results show that levels of the inorganic arsenic species called Arsenite (AS III) ranged up to 4.9 ppb in apple juice and up to 10.0 ppb in grape juice, while levels of the other inorganic arsenic species called Arsenate (AS V), ranged up to 7.4 ppb in apple and 10.5 ppb in grape juice samples.

The two types of organic arsenic that the FDA considers potentially harmful are known as dimethyl arsinic acid (DMA) and monomethyl arsonic acid (MMA). Our tests found DMA levels of up to 0.68 ppb in apple juice and up to 1.49 ppb in grape, while MMA levels ranged up to 7.56 ppb in samples of apple juice, but less than 0.16 ppb in grape juices tested.

Based on our juice tests results and other evidence from our investigation, Consumers Union, the advocacy arm of Consumer Reports, has urged the FDA to set legally binding standard of 3 ppb for total arsenic and 5 ppb for lead in juice. The FDA issued a public statement saying it welcomed the research undertaken by Consumer Reports and that it is collecting additional data to help determine if a guidance level can be established to reduce consumers' arsenic exposure. The additional data we are providing here should help toward that end.