An open-air conveyor belt was all that stood at the shut-down El Condor green onion packing plant operated by Dos M Sales de Mexico west of Mexicali. Inspectors said the plant, owned by a U.S. citizen, used untreated water from a nearby reservoir to wash the produce.
Even as U.S.-Mexican relations grew strained last week in the search for the source of hepatitis A outbreaks, U.S. officials were wrapping up their probe and concluding that the disease most likely originated in Baja California.
Investigators probably never will know for certain, said Jack Guzewich of the U.S. Food and Drug Administration.
"We don't have the proverbial smoking gun. We'd love to have it. We couldn't be happier for everybody's benefit," said Guzewich, the director of emergency coordination and response in the FDA's Center for Food Safety and Applied Nutrition.
Without conclusive proof, Baja California and Mexican federal officials have refused to accept the blame.
More than 900 people in North Carolina, Georgia, Tennessee and Pennsylvania became ill with hepatitis A after the outbreaks, linked to green onions, started in September. The disease attacks the liver and is caused by a virus spread by fecal matter from infected people.
The focus on Mexico has caused Baja California green onion exports to drop by half. And growers are wondering if they'll ever recover from being associated with the disease.
Javier Trujillo, director of Mexico's Food Safety and Quality Service, and Juan Pablo Hernández, Baja California agriculture secretary, have asked their nation's leaders to issue a formal protest.
No diplomatic note had been written by the end of last week, a spokesman at the Mexican Embassy in Washington said. "But we are very upset."
The rift also has caused consternation at the FDA.
"I understand they're on the defensive," Guzewich said. "I understand that they want to protect their industry and their livelihoods and their people and their businesses.
"But we have an obligation to Americans to protect the safety of the food that's served here. And we take that responsibility quite seriously," he said.
In an interview last week with The San Diego Union-Tribune, Guzewich provided new details of how the FDA and the Centers for Disease Control and Prevention investigated the source of the outbreaks and why they concluded the contamination probably originated in the fields or packing houses in Mexico.
"The way these investigations are done is through a process of elimination," Guzewich said. "You kind of have to disprove all the possibilities. As you go along, you disprove this possibility, you disprove the next possibility, disprove the next possibility. You work your way back through the system."
The probe started at the restaurants and other settings where fresh green onions were served.
The outbreak at a Chi-Chi's restaurant in Beaver County, Pa., in early November was the largest in the United States from a single source. As of last week, 640 illnesses and three deaths had been connected to onions at the restaurant. The green onions were chopped and served in mild salsa.
Once investigators ruled out restaurant workers and determined that the virus was carried in the onions, Guzewich said, they reviewed records and collected information that documented the food's trail.
Green onions, because they are perishable, move quickly through the distribution chain. They are shipped in the same box with a layer of ice to keep them fresh from the packing house through distributors to the final destinations.
"They were just containers moving through a system fairly quickly," Guzewich said. "There was no one importer or no one middleman in between a restaurant and an importer that accounts for all the episodes."
Because customers are used to receiving green onion shipments with fresh ice, distributors or wholesalers will re-ice the boxes.
Trujillo said U.S. investigators have not sufficiently investigated this aspect of the distribution chain. He wants binational teams to visit locations in the United States that might have used ice tainted with hepatitis.
"That's one of the things we're rechecking," Guzewich said.
"It is plausible that they were re-iced. But then the question becomes if they were re-iced, would that ice have been contaminated to cause people to get sick. And the way we reason that out is if one of the places that was re-icing had contaminated ice, then we would have seen a whole lot more people having gotten sick than we did."
Moreover, those places ship more produce than green onions, which would have meant people were getting sick from something other than onions. And that was not the case, Guzewich said.
The strains of hepatitis A found in the separate U.S. outbreaks are strains commonly seen either in U.S. residents who have traveled to Mexico and contracted hepatitis or in residents living along the U.S.-Mexican border.
"From there, all trails, so to speak, took us to Mexico," Guzewich said.
Visits to Mexico
Together with representatives of Mexico's agriculture and health ministries, FDA and CDC agents visited four Baja California companies that grow, pack and ship onions. Since Nov. 21, the FDA has halted imports to the United States by the companies.
They also visited an ice manufacturer that sells ice to two or three of the companies. And they visited other firms, mainly in the area around Ensenada.
"The difficulty we have in Mexico is the onions that would have been involved in Tennessee and Georgia would have been harvested in late July or early August. The onions that were involved in Pennsylvania would have been harvested in the month of September," Guzewich said. "We were there the first week of December."
What they found were fallow fields and nonoperating packing houses.
Nevertheless, the team gathered information by interviewing people, including growers, packers and health providers, and making observations at the dormant sites.
Mexican officials recently released the first reports from the investigation, saying three of the companies linked to the hepatitis outbreaks had acceptable practices but a fourth operator's were deficient.
They identified the deficient company as Dos M Sales de Mexico and the owner as Michael Brazeel, a U.S. citizen who has kept a low profile since the outbreaks.
"As far as we know, he hasn't shown his face," Baja California Agriculture Secretary Hernández said in an interview last week. "He has tried to disconnect himself from the problem. . . . He has left the state government and the producers to confront the crisis."
Brazeel operates a packing house, Empacadora El Condor, in La Rumorosa, west of Mexicali. The operation sits about 3½ miles off the free highway linking Mexicali and Tijuana, down an unpaved road in a small valley next to a reservoir.
The packing area sits in the open air on a concrete slab. There is a conveyor belt, and bare bulbs dangle from an electrical cord.
Caretaker Everardo Delgado said as many as 300 laborers pick and pack onions in the summer. They live in shacks constructed of plywood and cardboard.
Unpurified water from the reservoir was used in the operation's packing process, Mexican officials said.
A woman who answered the telephone Friday at Brazeel's residence in Yuma, Ariz., said there would be no comment on the allegations.
Guzewich said that operation had conditions "that were unacceptable by, I think, anybody's standards."
But he disagreed that the other companies' practices were acceptable.
"We're not going into the details of what we found, saying at farm A we found this and farm B we found that and farm C we found that," he said.
"All I can tell you is that at each farm we found a condition or conditions that was based on what we could observe when they weren't in operation and when they weren't growing any more onions right now. . . . We can say they had conditions that could have led to contamination."
Before they released the findings from the investigation, Mexican officials said all four companies were using contaminated water to wash and pack produce.
Given that U.S. officials could not link one company to all the outbreaks, the conclusion the investigators reached is that there is a general set of conditions that exists in Baja California that indicates there are opportunities for contamination, Guzewich said.
In addition, he said, the hepatitis A strain is present among Baja California residents. Many get the disease as young children, and, because of that, don't become as ill as adults.
"It only occurs in humans. So somewhere or other, you're being exposed to human feces, either directly or indirectly," Guzewich said. "It's either in the water or someone went to the toilet and didn't wash their hands well afterwards. It's not an elegant thing to think about, but that's the bottom line."
Guzewich said U.S. officials regret the hard feelings created in Mexico. The two countries have worked together on programs to prevent the spread of food-borne illnesses. Mexico is cooperating on enacting a new law to prevent bioterrorism in food shipments and is about to sign a memorandum of understanding to give Mexican officials more details about U.S. companies involved in tracing back an illness.
"This current situation is unfortunate with all the conflict back and forth," Guzewich said. "I'm hopeful that we will get past that, and we will continue to work cooperatively because, quite frankly, they have no choice, and we have no choice."