Cancer among 9/11 responders is 15 precent higher than among the general population say researchers in a study published yesterday in Environmental Health Perspectives.

Analyzing data from 20,984 participants in the WTC Health Program from 2001 to 2008, Samara Solan, MD, of the Icahn School of Medicine at Mount Sinai Medical Center in New York, and colleagues, found 575 cases of cancer as opposed to 499 expected in the general population for that size sample. In particular, thyroid, prostate and blood cancers, such as leukemia and lymphoma, showed the increase.

Researchers were surprised by lung cancer incidence rates, which were significantly lower than expected in both the initial and restricted analyses.

Although the study warns caution — in part because of the long latency period for most cancers — the findings highlight the need for continued follow up and surveillance of WTC responders. Dr. David Prezant, FDNY Chief Medical Officer, said,"What we can say is exposure to 9/11 increased the likelihood for their developing cancer."

Cancer is not covered under the James Zadroga 9/11 Health and Compensation Act's 9/11 Victim Compensation Fund. The Zadroga Act was passed by Congress in December 2010. However, cancers were left off the list of covered illneses due to a purported lack of scientific evidence that the disease was linked to toxic dust exposure.

In a recent decision handed down from Dr. John Howard, director of the National Institute for Occupational Safety and Health, cancers will be added to the list of covered illnesses after a period of public comment lasting several months.

Cancers among the participants in the WTC Health Program were identified through tumor registries in New York, New Jersey, Connecticut, and Pennsylvania. Then, standardized incidence ratios were calculated in order to compare diagnosis in responders with predicted numbers for the general population. Researchers noted the limitations of the study because the WTC Health Program is a voluntary program, which raises the possibility of self-selection bias.

According to the study, responders were primarily male (85 percent), white non-Hispanic (59 percent), never smokers (58 percent), and had a median age of 38 years on 9/11. The most common occupations were protective services and construction. Forty three percent of responders were exposed to the dust cloud on September 11. The median duration of service on site was 57 days.

Mount Sinai Hospital's World Trade Center Health Program reports that between 10 to 30 percent of the more than 27,000 rescue and recovery workers followed still have serious medical challenges ranging from respiratory and gastrointestinal disease to mental health issues.