The U.S. Food and Drug Administration this week said it won’t allow 23 shipments of orange juice or concentrate into the United States because its tests showed too much carbendazim. The FDA found 23 samples tested positive, meaning each sample, or shipment, contained 10 parts per billion or more of carbendazim. The agency detained or refused those 23 shipments. Of the 23 samples, 11 were from Canada and 12 were from Brazil. An additional 13 samples are still pending. The FDA said anything higher than 80 parts per billion could pose a health problem.

Carbendazim was used on citrus until 2008, but then alternatives became available. In some countries it is used to prevent mold from growing on trees. It is allowed in many countries but the Environmental Protection Agency has regulations against it in the United States.

As of this week, the FDA has collected samples from 99 shipments of orange juice or orange juice concentrate. Of these, 63 shipments tested negative for carbendazim and 46 of these shipments have already been released. Of the 46 samples, 21 were shipments from Canada, 16 from Mexico, two each from Costa Rica, and Trinidad and Tobago, and one each from Brazil, Lebanon, Dominican Republic, Honduras and Turkey.

The FDA started the tests Jan. 4, after Coca-Cola reported on Dec. 28 it found traces of carbendazim in samples of its orange juice brands, which include Minute Maid and Simply Orange. Coca-Cola also said it found low levels of the pesticide in competitors’ brands and in some concentrates on store shelves. Most of the orange juice used in the United States is grown in the United States. About 15-18 percent of Brazilian orange juice is used to supplement the demand.