By David Michaels

The National Football League, like many trade associations, has been disputing the long-term risks associated with employment in that industry. We’ve written about the league’s Committee on Mild Traumatic Brain Injury, supposedly independent but in fact dominated by individuals who work for NFL teams or the league itself. The Concussion Commission has been accused of downplaying the long term risks of football-induced brain injury. (Also see this post about one star running back’s fight with the NFL for work-related disability payments.)

Now Alan Schwarz, who has been covering the issue for the New York Times, has a report on new evidence of the terrible and previously hidden effects of football injuries on the brain.

Mary Strzelczyk spoke to the computer screen as clearly as it was speaking to her. “Oh, Justin,” she said through sobs, “I’m so sorry.”

The images on the screen were of magnified brain tissue from her son, the former Pittsburgh Steelers offensive lineman Justin Strzelczyk, who was killed in a fiery automobile crash three years ago at age 36. Four red splotches specked an otherwise tranquil sea — early signs of brain damage that experts said was most likely caused by the persistent head trauma of life in football’s trenches.

Strzelczyk (pronounced STRELL-zick) is the fourth former National Football League player to have been found post-mortem to have had a condition similar to that generally found only in boxers with dementia or people in their 80s. The diagnosis was made by Dr. Bennet Omalu, a neuropathologist at the University of Pittsburgh Medical Center. In the past five years, he has found similar damage in the brains of the former N.F.L. players Mike Webster, Terry Long and Andre Waters. The finding will add to the growing evidence that longtime football players, particularly linemen, might endure hidden brain trauma that is only now becoming recognized.

This is irreversible brain damage,” Omalu said. “It’s most likely caused by concussions sustained on the football field.”

The story is a tragic one:

Strzelczyk, 6 feet 6 inches and 300 pounds, was a monstrous presence on the Steelers’ offensive line from 1990-98. He was known for his friendly, banjo-playing spirit and gluttony for combat. He spiraled downward after retirement, however, enduring a divorce and dabbling with steroid-like substances, and soon before his death complained of depression and hearing voices from what he called “the evil ones.” He was experiencing an apparent breakdown the morning of Sept. 30, 2004, when, during a 40-mile high-speed police chase in central New York, his pickup truck collided with a tractor-trailer and exploded, killing him instantly.

The NFL was unwilling to provide a response or comment to the New York Times. But there will no doubt be more cases like this one, and the pressure to address the issue will continue to build. The players and the public deserve a credible investigation, and that can only take place if the inquiry is conducted by truly independent scientists.

David Michaels heads the Project on Scientific Knowledge and Public Policy (SKAPP) and is Professor and Associate Chairman in the Department of Environmental and Occupational Health, the George Washington University School of Public Health and Health Services.