Many of the thousands of people who have gone to court claiming ground zero-related illnesses don't have serious health problems, lawyers for the city claim in court papers.

About 10,800 plaintiffs claim to suffer from a wide variety of health problems from breathing toxic dust from the debris of the World Trade Center after the attacks of Sept. 11, 2001.

The claims are filed in federal court in Manhattan, where U.S. District Judge Alvin K. Hellerstein is overseeing the cases. About half were filed by city workers, including police officers and firefighters.

In a letter to Hellerstein last month, the law firm hired by the city, Patton Boggs LLP, contended that its review of the pending claims show about 30 percent of the people seeking compensation allege "only nominal injuries."

The letter, first reported by The New York Times, said 30 percent of claims involved cases where a specific ailment was not diagnosed. The claims instead describe symptoms, such as a runny nose or sleep problems.

"This is not to suggest that the remaining 70 percent of plaintiffs are seriously injured," the lawyers wrote. "To the contrary, diagnosable injuries such as sinusitis and acid reflux are not necessarily serious."

In fact, the lawyers contend, more than 300 of the claims, or about 3 percent of the total, "do not claim any past or current physical injury" at all.

A lawyer for suing ground zero workers, Marc Bern, disputed that 30 percent of plaintiffs don't suffer serious ailments.

In a separate letter sent to the judge last month, the workers' advocates suggested the two sides could work together to categorize claims by their severity.

Bern said that effort would be helped by additional medical records.

"We're continuing to get more records every day, virtually by the minute," he said Wednesday.

Lawyers for the workers say the city should stop fighting the claims and start paying them. The federal government created a $1 billion insurance fund to handle such claims. The fund is administered by the city.