Hollywood star Tom Cruise helped raise $1.2m (£657,000) to provide treatment for firefighters exposed to toxic gases during the 11 September attacks.
The detox regime was designed by Ron L Hubbard, founder of the Church of Scientology, to which Cruise belongs.
"I worried about those who had survived and been exposed," said the actor at a recent fundraising dinner.
"(I) knew immediately that not only would people be getting ill... but that it would be sooner rather than later."
"Once the towers had gone down and we were faced with the aftermath of their collapse, I could not get out of my mind that huge cloud billowing across Manhattan," said Cruise, who visited Ground Zero soon after the attacks in 2001.
The cash raised will help treat around 400 emergency workers at a detox centre on New York's Long Island.
The alternative treatment, outlined in Hubbard's book Clear Body, Clear Mind, uses "exercise, sauna sweat-out, vitamins and minerals" to help rescue workers cleanse their bodies of toxic materials.
Los Angeles-based Bridge Publications, which publishes Hubbard's non-fiction works, claims it has already helped some 200 emergency workers.
The technique, from the controversial Church of Scientology, has also been used to treat drug addicts.