Eighteen months ago, the U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS) signaled that the meat industry’s 2005 request to use low-dose irradiation as a processing aid to reduce unwanted microbes — and not have to label the meat as irradiated — was not getting much traction.

Late last week, FSIS finally issued its official decision on the petition: denied.

The American Meat Institute Foundation (AMI) had sought acceptance for chilled beef carcasses to be treated with low dose, low penetration electron beam irradiation to reduce disease-causing pathogens like E. coli. Winning approval of irradiation as a processing aid would mean the treated beef would be exempt from irradiation labeling. The industry doesn’t like the label requirement, because it thinks consumers misunderstand and won’t accept irradiation, despite its benefit in reducing health risks.

In a letter to the AMI, FSIS said it “has determined that the petition lacks sufficient detail” to warrant a new rule on irradiation as a processing aid, citing a lack of definition for the terms “low dose” or “low penetration,” as well as the lack of criteria in controlling the total absorbed dose.

AMI Foundation president Jim Hodges said those issues could have been worked out.

“FSIS cites technical reasons for the denial of AMI’s petition to treat carcass irradiation as a processing aid, when the petition simply asked FSIS to initiate the process of making a labeling policy change to encourage the use of irradiation technology,” Hodges said in a statement.

FSIS said the petition was being denied “without prejudice” and that AMI could submit a revised petition addressing the government’s concerns. Meanwhile, chilled beef carcasses can be treated with irradiation so long as the products meet existing requirements for total absorbed dose and for labeling, FSIS stated.

Irradiation as a food-safety technique has long been a controversial issue. On one hand, the process does not present health hazards or adversely affect a food’s nutritional value.  On the other hand, it’s an end-stage fix that doesn’t address preventing fecal contamination of the food supply in the first place.

Some say it’s a better alternative than others.

In January 2010, when the FSIS indicated its intent to reject or at least table the AMI’s petition, former under secretary of food safety Dr. Richard Raymond expressed disappointment, especially because of revelations that some beef products were being treated with ammonia as a processing aid to help reduce E. coli counts.

“So now the USDA does not have the spine to take on the consumer groups over another processing aid that would save lives,” wrote Raymond at the time.