The federal judge overseeing the settlement between ground zero workers and the city over health issues told the plaintiffs’ lawyers on Friday that they should absorb $6.1 million in legal expenses they had intended to pass on to their clients.

The judge, Alvin K. Hellerstein of Federal District Court in Manhattan, disallowed the charges at a hearing after rejecting lawyers’ justifications for the expenses, which involved interest paid on loans that helped finance about $30 million in litigation costs. Those loans had been at interest rates of 14 percent to 18 percent, and would have reduced the workers’ individual settlement amounts by from $78.23 to $2,300, on average.

Paul J. Napoli of Worby Groner Edelman and Napoli Bern Ripka, the law partnership representing the bulk of the more than 10,000 workers, argued that without the borrowed money, “it would not have been possible to litigate this case.” But Judge Hellerstein said that while he did not question the appropriateness or ethics of borrowing the money, he was concerned about the fairness of making the clients pay for it.

“The clients are entitled to the maximum return possible,” he said.

Legal experts say litigation financing has become more prevalent in recent years with the proliferation of companies devoted to helping not just lawyers and law firms, but also individual plaintiffs, while they await resolution of cases. The lawyers said they had properly disclosed the interest expense in their retainer agreements and presented testimony from two legal scholars to vouch for that and for the practice.