Arsenic is a poison that contaminates drinking water. The federal government sets limits on how much is allowed in bottled and tap water, but it puts no limits on arsenic in fruit juice.
Consumer Reports tested 28 apple juices and three grape juices purchased in the New York metropolitan area. Of the 88 samples analyzed, 10 percent had arsenic levels that exceeded federal standards for bottled and municipal water.
"The majority of the arsenic detected was the inorganic form, a known carcinogen linked to skin, bladder and lung cancer," said Dr. Urvashi Rangan of Consumer Reports.
And with 12 juices Consumer Reports tested, at least one sample contained lead levels that exceeded standards for bottled water.
"Our test was limited, so we can't draw any conclusions about any particular type or brand of juice. But the higher levels of arsenic and lead we found are troubling because many children drink a lot of juice, and their small body size makes them particularly vulnerable," Rangan said.
One likely source of the contamination is pesticides containing arsenic that were used in agriculture. Even though most are now banned, they can remain in the soil.
The advocacy arm of Consumer Reports is urging the Food and Drug Administration to set standards for juice.
"We think the lead limits should be five parts per billion, the current standards for bottled water, or even lower. And for arsenic, three parts per billion. That's attainable, 41 percent of the samples we tested met both those levels," Rangan said.
The Juice Products Association told Consumer Reports in a statement, "We are committed to providing nutritious and safe fruit juices ... and will comply with limits established by the Food and Drug Administration."
Oz's investigation in September sparked a fierce debate. ABC's Dr. Richard Besser argued research done by the FDA showed the arsenic found in some juices was harmless.
"You are telling parents that they are poisoning their children, and you have absolutely no evidence," Besser said to Oz.
The government shot down Oz's data, calling it faulty, inaccurate and alarmist.
But on Wednesday morning, Besser said the FDA had provided faulty data.
"They said there was an industry standard. It turns out there is not. They said the type of arsenic in apple juice was the safe kind. It turns out, it is not," he said.
Working with the new findings, Besser recommends that children 4 to 7 should have no more than 4 to 6 ounces a day. For older children, 8 to 12 ounces is safe.
The Food and Drug Administration said it is reviewing its own data to see if guidelines for juice should be set. It turns out the FDA has found levels of arsenic in apple juice that are even higher than what Consumer Reports' tests discovered.