It seemed like fear-mongering in September when daytime TV star Dr. Mehmet Oz said some of the top-selling brands of apple juice were laced with high levels of arsenic, which indeed sounds very scary.

Most news reports were skeptical when Oz suggested this presented an urgent public health risk, particularly to children, and the U.S. Food and Drug Administration called the claim irresponsible.

The FDA’s rebuttal noted that the Dr. Oz Show tests did not distinguish between naturally occurring, harmless organic forms of arsenic, which are not absorbed by the body; and inorganic forms of arsenic, suspected to be from pesticide residues, which can cause toxicity in large quantities over an extended period of time.

Now Consumer Reports has renewed the debate.

Consumer Reports tested 88 samples of apple juice and grape juice purchased in three states and found that 10 percent had total arsenic levels exceeding the federal standards of 10 parts per billion (ppb) for arsenic in drinking water, and that most of the arsenic “was the type called inorganic, which is a human carcinogen.” The tests also found that 25 percent of the juice tested had lead levels higher than the 5 ppb limit for bottled water.

The consumer watchdog used drinking water comparisons because there are no federal standards for arsenic in fruit juices. The FDA says its “level of concern” for heavy metals in juices is anything above 23 ppb.

Consumers Union, the advocacy branch of Consumer Reports, wants the government to set limits of no more than 3 ppb for total arsenic and 5 ppb for lead in juice, thresholds it says are reasonable because 41 percent of the samples it tested met both standards.

In its commentary on the report, Consumers Union said it was encouraged by the recent FDA letter to Food & Water Watch and the Empire State Consumer Project indicating that the agency is considering setting guidance for how much inorganic arsenic is permissible in apple juice, as well as analyzing the levels of organic and inorganic arsenic in other types of juice.

Sen. Tom Harkin, D-IA, chairman of the Health, Education. Labor and Pensions Committee, said that can’t happen soon enough.  In a letter to FDA Commissioner Margaret Hamburg, Harkin urged the agency to “act swiftly to set limits for total arsenic and lead in fruit juice,” enhance surveillance of imported juices and take regulatory action to ensure that contaminated juice doesn’t reach consumers.

Consumer Reports and Dr. Oz aren’t the first to test apple juice for arsenic. The St. Petersburg Times did so last year and found more than one-fourth of 18 samples contained between 24 and 35 ppb of arsenic. It noted that more than 60 percent of this country’s apple juice concentrate now comes from China, and that we also import a lot of apple juice from Chile, Argentina and Turkey, countries where pesticide use is under-regulated.

Arsenic-tainted soil in U.S. orchards is a likely source of contamination for domestically grown apples, Consumer Reports notes, because pesticides used here decades ago remain in the soil.

But the Consumer Reports tests showed that juice from China and Argentina did contain higher levels of inorganic arsenic than domestically produced juice, and also that organic brands of apple juice contained lower amounts of arsenic.

Meanwhile, federal food-safety officials say there still is no cause for worry.

“We continue to find the vast majority of apple juice tested to contain low levels of arsenic, including the most recent samples from China. For this reason, FDA is confident in the overall safety of apple juice consumed in this country,” the agency said in response to the Consumer Reports study, adding, “By the same token, a small percentage of samples contain elevated levels of arsenic.”

FDA acknowledged that after it downplayed the Dr. Oz report, it did not fully disclose eight of its own test results, including a 2009 sample with a level of  25 ppb and two 2010 samples with levels of 26 ppb and 34 ppb, because those tests were “in the process of being further verified.”  Of those three, one 2010 sample contained 43 ppb inorganic arsenic; the shipment it came from was denied entry into the U.S. The two others had less than 23 ppb inorganic arsenic, the agency said.

The FDA says it has expanded its surveillance and if it finds too much inorganic arsenic, it will remove that juice from the market.

Meanwhile, the Juice Products Association claims all these reports are getting it wrong.

“Consumer Reports and other media outlets erroneously compare juice to the standards for drinking water. Juice is not water. To compare the trace levels of arsenic or lead in juice to the regulatory guidelines for drinking water is not appropriate because regulatory agencies have set lower thresholds for drinking water than for food and other beverages because people consume larger amounts of water. When FDA experts in food safety and toxicology developed the level of concern for juice, it took into account juice consumption among people of various ages, including children.”

Consumer Reports says a poll of parents found that 35 percent of children 5 and younger drink juice in quantities exceeding doctors’ recommendations. The American Academy of Pediatrics advises that fruit juice not be given to children until they are six months old, and then no more than 6 ounces a day until they’re 6. Weight problems and tooth cavities are the risks the pediatricians cite for drinking too much juice. They also note that juice lacks the fiber and nutrients available in whole fruit.