The Food and Drug Administration said final tests confirmed that three samples of Canadian orange juice were negative for the fungicide carbendazim. The sample findings allowed corresponding shipments from Canada into the U.S. market.

But there was no word about Brazilian orange juice, which has riveted industry attention and sent the commodities market for orange juice on its wildest rollercoaster ride in more than 20 years.

Test results have yet to be announced for 28 import samples from Brazil, Mexico and Canada. "Other samples are still pending and won't be released until next week," said FDA spokeswoman Siobhan DeLancey.

In a move that suggested testing could continue for some time, the regulatory agency said it planned to set up an online fact sheet that would be updated on Fridays.

The fungicide scare began after Atlanta soft-drink giant Coca-Cola Co. discovered carbendazim in shipments from Brazil and alerted U.S. authorities about a potential industry-wide problem. Coke is the maker of Minute Maid orange juice.

Carbendazim is used in Brazil to combat blossom blight and black spot, a type of mold that grows on orange trees.

But in the United States, it can be used only in non-food items such as paints, textiles and ornamental trees. U.S. authorities still allow trace amounts of carbendazim in 31 food types including grains, nuts and some non-citrus fruits -- but not in citrus juice.

The FDA said low levels of carbendazim are not dangerous and the agency had no plans for a recall.

But U.S. action to halt any imports with detectable levels of the chemical fanned market worries about orange juice supplies. Uncertainty over the import clampdown has already caused exporters to postpone shipments to the United States.

Brands such as Tropicana, from PepsiCo Inc., and Coke's Minute Maid may contain a mix of juices sourced from Brazil and the United States.

The FDA said testing typically takes four to five business days when no carbendazim is found during initial screening, and an additional seven days if further tests are necessary.

U.S. officials will allow any imported products containing less than 10 parts per billion to enter the United States, but will refuse entry to anything with higher levels.

The European Union allows imports with up to 200 ppb. The Environmental Protection Agency, which regulates fungicides in the United States, considers several thousand parts per billion to be a health risk.

The chemical is banned in Australia.

The FDA said importers will have 90 days to export or destroy any product that has been refused.

(Additional reporting by Josephine Mason in New York)

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