WASHINGTON — Parents should be informed before they sign up their kids to play football that the sport can cause long-term neurological damage, even to players who don’t have obvious concussion symptoms, NFL Hall of Famer Harry Carson told a congressional panel on Friday.

Carson, other former players and brain-injury researchers spoke at a forum organized by House Democrats who are exploring what, if anything, Congress can do to make the nation’s most popular spectator sport safer.

The former linebacker, who made nine Pro Bowls and won a Super Bowl in his 13-year career with the New York Giants, now devotes much of his time to raising awareness of head trauma and said he will not allow his 8-year-old grandson to play football.

“Every parent should be informed. They should be informed as to what risks they are subjecting their kids to,” said Carson, who was diagnosed with post-concussion syndrome in 1990. “Understand that your child could be subject to a neurological injury that could affect them for the rest of their lives.”

After the forum, Carson acknowledged his disappointment that head trauma in football, like so much in Washington these days, has become a partisan issue. Rep. Frank Pallone, a New Jersey Democrat who organized the forum along with Rep. John Conyers of Michigan, said Republicans had no interest in convening a formal hearing on the subject. And several members denounced President Donald Trump for his recent suggestion that the NFL is less enjoyable since the league began taking steps to address player safety.

“It won’t be a partisan issue if it affects some of their children,” Carson said of Republicans.

The NFL declined to send a representative to the forum.