Bell spoke on Saturday, one day after the NFL suspended him for the first three games of the regular season for missing multiple drug tests, which is a violation of the league's substance abuse policy.
"I already apologized to my teammates, my coaches and Steeler Nation," Bell said. "I'm sincerely sorry about everything I put everybody through. It's been frustrating, and I own up to everything. It's all my fault, and I can't blame nobody else for that."
Bell stood by a now-deleted post to his Instagram account he put up on Friday, offering an apology shortly after the suspension was announced. He initially faced a four-game suspension, but it was reduced to three games following an appeal to the league.
Bell will be eligible to return to the active roster Sept. 26 before the team's Week 4 home game against Kansas City.
"I'm glad they shaved a little bit of time off," Bell said. "The sooner I can get on the field, the better."
This is the second time Bell has faced discipline from the league. He sat out the first two games of the 2015 season as punishment for his arrest in August 2014 on DUI and marijuana possession charges following a traffic stop. Bell was originally suspended three games before it was reduced on appeal.
"It [stinks] to keep having to miss time," Bell said. "I want to play football and be out there with my teammates. I accept the suspension. I just have to learn from this and move on."
Bell said he feels the experience will help him moving forward.
"I think this is going to help me be a better person, a better player, and obviously smarter," Bell said. "It's definitely a learning experience. I'm not the perfect person. I didn't do everything right, but I didn't do everything wrong either."
Rumors initially surfaced about Bell's suspension during the team's June minicamp. He declined to get into specifics when the Steelers opened training camp as additional information circulated about the case. Bell said he doesn't let those rumors bother him.
"I just let everybody say what they want to say," Bell said. "People who say I smoke weed, that's fine. Everybody is entitled to their own opinion. The people who know me know the person I am."
While Bell is scheduled to return in Week 4, the Steelers aren't sure when tight end Ladarius Green will be back.
Green, the Steelers' biggest free-agent signing in the offseason, is on the physically unable to perform list because of offseason ankle surgery. On Saturday, Green denied multiple recent reports that he was suffering from recurring headaches.
"I don't know what those reports are," Green said. "I heard about it, but I didn't look at it. I'm still on PUP because of my ankle."
There were also reports suggesting the Steelers could release Green or that he was contemplating retirement.
"I'm wondering who said this," said Green, who enters his fifth season. "I'm only 26, so I don't think I'm going to retire anytime soon."
Green said there's no timetable for his return. He admits he's frustrated, but he's confident that he will play this season as he continues to rehabilitate his ankle and work out on adjoining practice fields.
"I've still been rehabbing my ankle," Green said. "I haven't been dealing with anything else but that."
In other news, quarterback Dustin Vaughan suffered a fractured bone on his throwing hand during a sack in the second preseason game Thursday against the Eagles. The Steelers signed quarterback Bryn Renner and guard Antoine Everett and released running back Christian Powell and center Valerian Ume-Ezeoke.