A three-month-old pig sits in a pen in Iowa. Under a proposed new system, plant owners would be allowed to run pork plant slaughter lines as fast as they want. (Daniel Acker/Bloomberg News)

The Office of Inspector General is evaluating whether the U.S. Department of Agriculture concealed information and used flawed data to develop and promote a new hog inspection system that would shift many food-safety tasks from federal inspectors to pork industry employees.

The USDA’s inspector general, Phyllis Fong, notified 16 members of Congress on Friday that her office has launched the probe in response to concerns the lawmakers raised in March, according to a letter obtained by The Washington Post.

Under the proposed new system, plant owners would be allowed to run pork plant slaughter lines as fast as they want, a provision that has worker safety advocates concerned that worker injury rates would rise. The USDA said in a proposed rule — which if finalized would create the new system — that its data shows worker injury rates probably would be lower than those at traditional plants where limits are placed on line speeds.

Sen. Richard J. Durbin (Ill.), the second-highest-ranking Senate Democrat, and more than a dozen other Democrats sought the inspector general’s probe after two university experts reviewed the USDA’s data and analysis and concluded “it is impossible” for the department to “draw any statistically valid conclusion about worker injury rate differences.”

The data was not released until months after the 60-day public comment period for the rule had closed in April 2018 and only after Freedom of Information Act requests were filed by a Texas State University researcher and a worker safety advocacy group, the National Employment Law Project.

Durbin, who says he worked in a slaughterhouse for a year as a college student, said Monday he is glad the inspector general is heeding his request, adding that line speeds are “directly linked to worker safety.”

“Bowing to the meatpacking industry, the USDA relied on sketchy data to justify a major inspections change that could create unsafe working environments at pork processing plants in America,” Durbin said in a prepared statement for The Post. “I am concerned that the USDA also tried to hide this data from the public.”

Debbie Berkowitz, a worker-safety expert with the law project, asked USDA officials to extend the public comment period to allow others to examine and remark on USDA’s data and its worker safety analysis, records show. No extension was granted.

A Post analysis of the public comments showed that out of 84,000 public remarks made on the rule, 87 percent were either opposed or expressed negative opinions about the proposal. In numerous instances, groups asked for additional information to properly evaluate the proposal.

“The bottom line here is USDA is rushing this rule through and really abandoning any effort to be transparent,” Berkowitz said in an interview.

USDA declined to comment on the Inspector General probe. In earlier statements, it has said the Occupational Safety and Health Administration, not USDA, has the “statutory and regulatory authority to promote workplace safety and health.”

Berkowitz, who was OSHA chief of staff during the Obama administration, said the USDA does not “police companies about worker safety.” However, she said, “They should not be in the business of giving a green light to something that could cause further injury to workers.”

Illness rates for people who work in the meatpacking plants — including carpal tunnel syndrome and tendinitis — are 16 times higher than the average for all other industries, according to the U.S. Bureau of Labor Statistics.

The proposed hog-slaughter rule is based on a study that began 20 years ago, ultimately including five large plants. Efforts to expand the program have sputtered under past administrations, but Trump administration officials have pushed forward with the rule and hoped to finalize it this summer.

The USDA expects 40 of 612 hog plants will use the new system. Collectively, agriculture officials say, these plants will account for 90 percent of the pork produced in the United States.

In her letter to Durbin and other lawmakers, Fong said her office will seek to determine whether the USDA did the following: complied with federal public transparency requirements; made information about its preliminary analysis on worker safety clearly accessible to the public during the comment period; adhered to the department’s own data quality guidelines; came to a reasonable determination about the reliability of OSHA injury data; and consulted with OSHA and the National Institute for Occupational Safety and Health as it developed the rule.

The inquiry is expected to be complete by the end of the year, an inspector general spokeswoman said.

On Tuesday, the House of Representatives passed a 2020 appropriations bill that provides funding for USDA. However, the bill also requires that the Inspector General perform a more extensive data review before any funds are used for the new inspection system.

That requirement, proposed by Rep. Rosa L. DeLauro (D-Conn.), would also include an examination of USDA data the department used to conclude that pork produced under the new system would be as safe as pork produced at plants using the traditional inspection system. It would also examine data USDA used to conclude the increased line speeds would not impact animal welfare. DeLauro called the proposed rule a “giveaway to large corporate meatpackers.”

In response to the inspector general’s probe, DeLauro said it is “an important first step toward ensuring the swine inspection rule changes are based on sound science by opening an investigation into the department’s use of flawed worker safety data. However, the OIG must expand their investigation to encompass all data USDA used to develop the proposed rule — as would be required by a provision I included in this year’s USDA funding bill.”

In an earlier statement, the North American Meat Institute, an industry group that supports the proposal, said: “This rule is founded on years of sound scientific data and experience. NAMI supports risk-based, science-driven food safety systems. Consumers deserve no less.”

Andrew Ba Tran contributed to this report.