Although government officials were quick to hypothesize that dust from an air conditioning repair was the likely cause of the major listeria outbreak last December at Bil Mar Foods, Zeeland, Mich., there is still no proof after six months of investigation. A final report had been expected months ago.

The News submitted Freedom of Information Act (FOIA) requests to the Centers for Disease Control and Prevention (CDC) and the United States Department of Agriculture (USDA) to try to shed some light on their a/c investigation.

However, both agencies have withheld certain documents, declaring that they are not required to disclose any “predecisional” analyses.

One USDA document obtained by The News referred to a CDC analysis of the a/c hypothesis in an “attached appendix.” But the appendix was not released.

The News objected to the government’s early finger-pointing at air conditioning equipment and repair procedures, and has challenged the CDC and USDA to prove their claims.

Lynn Armstrong, the CDC’s FOIA officer, told The News that she was “withholding documents containing predecisional internal communications, raw data, and drafts.

“Release of this type of material would interfere with the agency’s deliberative process,” she said.

Cheryl A. Hicks, team leader, executive management staff of the USDA, also said she would not release “intra- and inter-agency communications that contain or consist of sensitive, candid, predecisional comments.”

While the two agencies would not reveal their reasons for keying on last July’s a/c repair, other documents show numerous unsanitary conditions at the Bil Mar Plant that occurred throughout 1998.

Rampant problems

Because listeria is an environmental bacteria, prevalent in dirt and dust, stated Jill Hollingsworth, vice president of food safety, Food Marketing Institute, “The best weapon or tool you have against listeria is just really good sanitation.”

Hollingsworth said that food plants must follow “sanitation standard operating procedures, which is a requirement that they are able to demonstrate every day before they begin production that the plant is in fact clean and sanitary, and has met USDA standards for sanitation.

“During the day, they also have operating sanitation that they must maintain.”

USDA inspectors are on-site daily to ensure compliance.

However, USDA documents obtained by the Detroit Free Press and Chicago Tribune under the FOIA, indicate that inspectors often saw sanitation problems last year at Bil Mar. Cockroaches were found more than once. Clear plastic strips were discovered in some food. Workers ignored proper hygiene.

Equipment was not fully cleaned, leaving dried meat inside. Dropped knives and thermometers were picked up and used on the food.

Inspectors also reported the possible falsification of plant records, indicating food safety checks that hadn’t actually taken place.

Hicks noted that the CDC investigation is ongoing, but one official admitted that there may never be a final answer.

On May 25, the USDA announced short-term steps to control Listeria monocytogenes in ready-to-eat products. It advised food plants to reassess their HACCP (Hazard Analysis and Critical Control Points) systems — a preventive control program — to make sure they are adequately addressing listeria. The agency is also recommending environmental and end-product testing.

The Bil Mar listeria outbreak resulted in 100 illnesses in over 22 states. There were a total of 21 deaths — 15 adults and six miscarriages.

The outbreak was the second worst ever in the United States and Bil Mar’s meat recall was the biggest ever.

This year there has been an increase in the number of recalls due to listeria contamination, with more than a dozen reported as of the beginning of June, compared to six all of last year.