From the New York Times
By ANDREW MARTIN
Published: November 25, 2008
The Food and Drug Administration said Tuesday that it had discovered the toxic chemical melamine in infant formula made by an American manufacturer, raising the possibility that the problem was more extensive in the United States than previously thought.
While few details were available late Tuesday, agency officials said they had discovered melamine at trace levels in a single sample of infant formula. It was also discovered in several samples of dietary supplements that are made by some of the same manufacturers who make formula.
F.D.A. officials insisted that the levels of melamine were so low that they did not pose a health threat.
“There’s no cause for concern or no risk from these levels,” said Judy Leon, an agency spokeswoman. Ms. Leon said the contamination was most likely the result of food contact with something like a can liner, or from some other manufacturing problems, but not from deliberate adulteration.
She declined to name the company that made the tainted infant formula.
Melamine contamination became a major scandal in China after it was added to milk to disguise test results that measure protein levels. Since it was discovered in infant formula in September, it has sickened more than 50,000 infants and killed 4.
The F.D.A. has beefed up its inspections of Asian markets to make sure that infant formula and other products from China are not contaminated with melamine. At the same time, the agency said it had received assurances from American infant formula manufacturers that they did not import ingredients from China.
To date, several products carried primarily by Asian markets have been recalled because of melamine contamination, including certain varieties of Mr. Brown instant coffee and tea, White Rabbit Creamy Candy and Blue Cat Flavor Drink. Two weeks ago, the F.D.A. said all Chinese products containing dairy ingredients would be stopped at the border until importers proved they were not contaminated.
Though manufacturers of domestic infant formula say they do not use Chinese ingredients, the F.D.A. began sampling infant formula anyway, using more sophisticated testing than had previously been available.
Ms. Leon said the agency was testing 87 samples and had completed all but 10 of the tests. Of those, only one contained traces of melamine, she said. The F.D.A. allows anything below 250 parts per billion of melamine in infant formula, and the sample contained less than that, she said.
Ms. Leon said the other products containing trace elements of melamine were also below allowable levels. For supplements, the F.D.A. allows 2.5 parts per million, and she said all of the samples testing positive were below that figure.
From the World Health Organization’s page of Questions and Answers about Melamine:
What is melamine?
Melamine is an organic based chemical most commonly found in the form of white crystals rich in nitrogen.
What is melamine generally used for?
Melamine is widely used in plastics, adhesives, countertops, dishware, whiteboards.
Why was melamine added into milk and powdered infant formula?
In China, where adulteration has occurred, water has been added to raw milk to increase its volume. As a result of this dilution the milk has a lower protein concentration. Companies using the milk for further production (e.g. of powdered infant formula) normally check the protein level through a test measuring nitrogen content. The addition of melamine increases the nitrogen content of the milk and therefore its apparent protein content.
Addition of melamine into food is not approved by the FAO/WHO Codex Alimentarius (food standard commission), or by any national authorities.
Has melamine been found in other food products?
In 2007, melamine was found in wheat gluten and rice protein concentrate exported from China and used in the manufacture of pet food in the United States. This caused the death of a large number of dogs and cats due to kidney failure.
In the present event, melamine contamination has been found in a number of different brands of powdered infant formula, in one brand of a frozen yogurt dessert and in one brand of canned coffee drink. All these products were most probably manufactured using ingredients made from melamine-contaminated milk.
What are the health effects of melamine consumptions in humans?
While there are no direct human studies on the effect of melamine data from animal studies can be used to predict adverse health effects. Melamine alone causes bladder stones in animal tests. When combined with cyanuric acid, which may also be present in melamine powder, melamine can form crystals that can give rise to kidney stones.
These small crystals can also block the small tubes in the kidney potentially stopping the production of urine, causing kidney failure and, in some cases, death. Melamine has also been shown to have carcinogenic effects in animals in certain circumstances, but there is insufficient evidence to make a judgment on carcinogenic risk in humans.