More than 550 people have signaled their intent to join a state court lawsuit alleging that toxic contamination from the Love Canal landfill has created a “public health catastrophe” for neighbors of the site in Niagara Falls.

“We’ve filed in excess of 550 notices of claim, and I believe the number is closer to 600,” plaintiffs’ attorney William H. Mack told The Buffalo News on Wednesday. “This is a mechanism for notifying municipal defendants that these individuals are contemplating filing complaints alleging that they have suffered damages as a result of exposure to Love Canal contamination.”

Filing a notice of claim is a legal procedure required to file a lawsuit against a government agency in New York State’s courts.

Mack said he anticipates that many of those 550 people will join a lawsuit filed lasy year that seeks $113 million in damages, year, alleging that toxic chemicals have leaked away from the 21,800-ton toxic landfill that is maintained – under government supervision – by a subsidiary of Occidental Chemical Corp.

Some of the 550 are current residents of the area that has been declared safe, while others have moved out.

An updated complaint filed by the plaintiffs Friday refers to the alleged new problems at Love Canal as a “public health catastrophe.”

Government agencies deny that there is any health emergency.

Among the injuries that one or more plaintiffs suffer are birth defects, chromosomal abnormalities, bone marrow abnormalities, cardiac conditions, pulmonary symptoms, unexplained fevers, skin conditions, behavioral problems, learning disabilities and loss of teeth, according to the complaint.

Many of the plaintiffs’ homes are “virtually unsalable” because of widespread contamination problems in the neighborhood, according to the latest court documents.

Some residents who live near the landfill have criticized the lawsuit as nothing more than a money grab orchestrated by attorneys seeking to cash in on events that occurred at Love Canal decades ago.

But supporters of the legal action, including Stephen U. Lester, science director of the Center for Health, Environment and Justice, say that it was a huge mistake for government officials to allow resettlement of the neighborhood that was declared an environmental disaster area in the late 1970s, leading to the evacuation of hundreds of families.

The lawsuit, originally filed by three families who lived near the landfill, alleges that some people have been made seriously ill by exposure to chemical wastes that are supposed to be securely stored at the landfill.

Those allegations have been vehemently denied by officials of Glenn Springs Holdings, the Occidental Chemical subsidiary; in addition to the City of Niagara Falls, the U.S. Environmental Protection Agency and the state Department of Environmental Conservation.

Those government agencies insist that the neighborhood is safe – for hundreds of families who live nearby, for senior citizens who attend activities at a city-run senior citizens center directly adjacent to the landfill, and for children who use a playground next to a landfill and a nearby baseball/softball facility.

The early 2011 finding of toxic chemicals in a sanitary sewer line on Colvin Boulevard, just outside the landfill property, should not be viewed as an indication that chemicals are leaking away from the landfill, those government agencies contend.

The agencies do not see any specific environmental concerns “from the recent sewer repair work, from ongoing public water line repair work, or from the ongoing containment operations being conducted at the Love Canal site,” said a federal attorney in a letter sent this month to U.S. District Judge John T. Curtin, who inquired about the status of Love Canal.

Curtin, who spent nearly 20 years overseeing a federal Love Canal lawsuit that ended in 1998, said he sent a letter to state and federal officials because he was alarmed by articles in The News on the new litigation in state court.

“Proper operation of the Love Canal containment and treatment system is an issue that DEC takes very seriously and monitors closely,” said Emily DeSantis, a state DEC spokeswoman. “The protective systems in place are operating properly and monitoring data does not indicate any system failures or leaks.”

The DEC said Wednesday that it has not changed its position, despite the news that 550 more people may join the lawsuit. Eric P. Moses, a spokesman for Occidental and Glenn Springs Holdings, had no immediate comment late Wednesday. He stated last month that the companies’ top priority is making sure the landfill is operated in a manner to protect the public safety.

According to Mack, research and chemical testing done by the plaintiffs’ legal team indicates that there are problems with toxic contamination in the neighborhood.

He declined to make public the notices of claim but said that most of the complaints made by potential new plaintiffs are similar to those made by the three families who filed the lawsuit last year.

The families who filed suit last year alleged that their residential properties are contaminated with toxic chemicals and said that they have suffered from respiratory ailments, skin rashes, severe headaches and other illnesses. One of the families said their baby boy was born last year with clubbed feet and other birth defects.

“We’re still analyzing the new claims. We’re not giving details of them at this time. We do anticipate filing additional complaints, and most of the complaints are similar to those we filed last year,” Mack said. “No two stories are the same.”

Mack added that the legal team still has experts conducting environmental testing in the neighborhood. He said details of what is found will come out later in the litigation.

“We do not solicit these cases,” Mack said. “These folks come to us because they need help. Some of them are very emotional.”