The metal contamination issue, concerning the cookies and cream flavor of Formula 1 made at the plant in Lake Forest, Calif., came into focus in early 2011.
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"We have a serious problem with metal contamination that we discovered over the weekend," Joseph Plunkett, the company's senior vice president for worldwide manufacturing and engineering, said in a private meeting on Jan. 10 that included Richard P. Goudis, the company's chief operating officer, according to the documents reviewed by The Times.
A stainless steel screen in the production line was apparently defective, throwing off small wires that were used to hold the mesh onto its frame, Mr. Plunkett said. Though a magnet was supposed to catch any shards of metal in the product, the stainless steel of the screens was "not magnetic," Mr. Plunkett said on Jan. 10.
"Production was stopped temporarily and an investigation was conducted," according to a statement provided by Herbalife summarizing the events.
In addition to replacing the screen, the company quarantined much of the contaminated powder. The powder that had already been packaged—a "small" amount—was disposed of, according to a person briefed on the matter. But even with the inspection plan in place, doubts lingered. "Maybe, in hindsight, we would have shut it down a little sooner," one senior executive said in the Jan. 10 conversation.
Herbalife also moved to obtain X-ray equipment to inspect the potentially contaminated bottles, the documents show. In a Jan. 18 conversation, Mr. Plunkett said the inspection with the X-ray machine would start the following week and would likely take three weeks to complete. The company ultimately decided against using an X-ray machine because of concerns that the cookie crumbs in the formula would be difficult to distinguish from metal shards.
Before long, production on that line was restarted.
"We are getting up near 100 bottles a minute," Mr. Plunkett said on Jan. 24, to which Mr. Goudis said, "Wow," according to the documents.
But another concern soon arose: the monorail system for the "super sacks" that contained the raw ingredients had been shedding, with pieces of metal falling into the product, according to a person briefed on the matter.
The solution involved putting a pan beneath the equipment to catch the falling shards, this person said.
Production was halted on Jan. 25 to address this second issue, according to an internal operations report. As part of the investigation, the EAS Consulting Group, a consulting and auditing firm for the dietary supplements industry, was retained to advise on the cleanup, Herbalife said in the statement.
The inspection process involved opening sealed bottles and running them through a metal detector to "confirm the absence of metal contamination," Herbalife said. The bottles and the bulk powder that made it through the process were cleared for release.
The production line was restarted on Feb. 16.
Herbalife said in a statement that the factory "operates at the highest quality and sanitary standards and its operating procedures are designed to comply with or exceed the appropriate current good manufacturing practices for foods and dietary supplements."
—By The New York Times