WASHINGTON — The president of a Tennessee state university, under fire for an academic study on truck emissions that was paid for by a local trucking company, has asked federal officials to disregard the study, at least for now, in its review of pollution regulations that could benefit the company.
In a letter to the Environmental Protection Agency, Philip B. Oldham, the president of Tennessee Technological University, warned that “experts within the university have questioned the methodology and accuracy” of the study, and that an investigation was being conducted into its findings.
The letter was dated Monday and sent to Scott Pruitt, the administrator of the E.P.A., as well as Representative Diane Black, Republican of Tennessee, who had pushed Mr. Pruitt and the E.P.A. to approve a change in regulations that would exempt certain heavy-duty trucks from a requirement to install modern emissions control systems.
One of the main beneficiaries of such a change would be Fitzgerald Glider Kits of Byrdstown, Tenn., the country’s largest manufacturer of so-called glider trucks, which are equipped with rebuilt engines that do not have modern emissions controls. The company paid for the study, and had offered to build a new research center for Tennessee Tech on land owned by the company.
The study, which concluded that pollution from glider trucks was no worse than from trucks with modern emissions controls, was cited by Mr. Pruitt when he announced in November he would make the regulatory change requested by Ms. Black. Last June, Mr. Oldham had signed a letter endorsing the study.
The Obama administration had moved to eliminate the exemption for the glider trucks, given the health threat associated with their emissions. The E.P.A., in its own analysis, estimated last year that gliders emitted nitrogen oxide levels during highway operations that were 43 times as high as those from trucks with modern emissions control systems.
The E.P.A., in a written statement Wednesday, said that Mr. Pruitt’s move to exempt the glider trucks was based on a legal determination that the agency did not have the authority to regulate them, not the findings of the Tennessee Tech study.
“E.P.A. did not rely upon the study or even quote directly from it,” the statement said, adding that the agency “only noted the existence of the study,” and its findings, when Mr. Pruitt moved to exempt the glider trucks.
A lawyer for Fitzgerald did not respond on Wednesday for a request for comment.
The letter from Mr. Oldham followed a separate letter on Friday from Darrell Hoy, interim dean at Tennessee Tech’s College of Engineering, directed to faculty leaders at the university. It urged Mr. Oldham to suspend the university’s support for the study, which Mr. Hoy said was largely handled by a graduate student, not an engineering expert.
“No qualified, credentialed engineering faculty member (1) oversaw the testing, (2) verified the data or calculations of the graduate student, (3) wrote or reviewed the final report submitted to Fitzgerald, or (4) wrote or reviewed the letter submitted to Diane Black with the far-fetched, scientifically implausible claim, that remanufactured truck engines met or exceeded the performance of modern, pollution-controlled engines with regards to emissions,” Mr. Hoy’s letter said.
A group at the university, describing themselves as a “coalition of concerned faculty, students and community,” have called a rally on campus on Thursday morning to “shine the light on the unethical practices” exposed by the incident.
Separately, at least one ethics complaint has been filed with the Tennessee Bureau of Ethics and Campaign Finance, questioning whether Ms. Black, who is running for governor, improperly accepted donations from Fitzgerald corporate entities late last year that exceeded campaign contribution limits.
In an article last week, The New York Times found that corporate affiliates of Fitzgerald, employees or family members contributed at least $225,000 to Ms. Black around the same time Mr. Pruitt moved to protect the trucks.
A spokesman for Ms. Black said last week that she had complied with the state’s campaign finance law.