dr. prezant's study may change our understanding.ebuona a study doesn't address his most urgent concern. is his cancer back? >> if it's more bad news i'm going to faint. >> hello. >> hi. >> how are you? >> okay, very good. >> i've got good news for you. >> what's that? >> looks good. >> oh, great. >> i might actually have to spring you. can you stand it? will you miss me? i'll miss you. i will. >> that's five points on a star. for one year every year cancer free. >> nice. >> wear that with pride, all right? >> thank you. >> i've gotten my life back. i feel like a feather floating in the wind right now. i just feel great. >> emma. >> yeah? >> i love you, hon. >> i love you too, daddy. >> give me a kiss. >> how many more of those you got? >> marty fullum is also trying to get his life back. >> how are you feeling today? >> doing well today. >> keeping fit. taking a regimen of pills. >> it's about 40 pills a day, yeah. >> and undergoing painful treatments. all in the hopes of qualifying for another transplant. and yet despite all that e

dr. prezant watched the tragedy evolve. >> their lung capacity decreased 30%. in the first six months after 9/11, on average, they dropped 370 milliliters. 12 times what they, themselves, were decreasing just due to aging. that is unheard of. >> marty? >> marty was over 1,200 milliliters. >> 40 times. >> prezant knew the dust was affecting marty's lungs. his immune system was attacking his muscles. 65-pound weight loss in three weeks? >> i couldn't walk. i wouldn't breathe. >> if there is any good news out of all of this, it is everything we tested for, which includes asbestos and lead and vocs have been below the concern for the public health. obviously for those who are down here, this is very important. >> in september of 2001, there were reassurances, but the testing required to make any statement about air quality had not been completed. so could anyone really say the air was truly safe? >> september 18th, the epa commissioner waved the all clear sign. was that appropriate? >> no, it was not. it definitely was not. she did not have enough information to ma

dr. prezant's study was released, the study of health found no link between cancer and dust. his study may change that standing. >> does this change anything for the first responders or rescue workers? >> whether we can say that cancer is increased in other responders or other residents, we have no idea. this is a study about firefighters. their exposure is unique. 85% of the exposed were present in the first 48 hours of the collapse when the exposure was massive. that is a very unique exposure. >> as for ernie valabona, this study doesn't confirm this cancer was caused by the dust. for him? there is no doubt. >> i firmly believe that. >> it is a tough thing to prove? >> maybe there is no stud toy prove that, but the common man, common sense answer would be yeah. there are too many people getting these blood disorders and cancers and respiratory problems. >> there is more to ernie's story as well. you can see it all and what other police and firefighters have gone through and rare never before seen footage from that day. my full investigation of the health fallout from 9/11 i

dr. prezant and others believe may have been the genesis of the cancers. respiratory problems, yes.ade sense to everybody. the cancers they're starting to develop some ideas as to the mechanism, looking at that dust. >> and these are folks who rushed down there and worked there for weeks and weeks and months and months. regardless of their own concerns at the time about not having the proper equipment or anything. they were there every single day and around the clock. based on the results of the new study, will these people be able to get coverage? >> you know, anderson, i can tell you, i think this is going to be one of the more controversial things with regard to health, and certainly with with regard to health and the pile that you're looking at there. it's already been a big source of controversy. what i will say is we reached out to niash, the national institute of occupational safety. they say they're going to take this into account. they haven't changed their recommendations since july, but at their next review meeting which is next year, the study is going to be one of the s

dr. prezant and others believe may have been the genesis of the cancers. respiratory problems, yes.o everybody. the cancers they're starting to develop some ideas as to the mechanism, looking at that dust. >> and these are folks who rushed down there and worked there for weeks and weeks and months and months. regardless of their own concerns at the time about not having the proper equipment or anything. they were there every single day and around the clock. based on the results of the new study, will these people be able to get coverage? >> you know, anderson, i can tell you, i think this is going to be one of the more controversial things with regard to health, and certainly with with regard to health and the pile that you're looking at there. it's already been a big source of controversy. what i will say is we reached out to niash, the national institute of occupational safety. they say they're going to take this into account. they haven't changed their recommendations since july, but at their next review meeting which is next year, the study is going to be one of the studies they

dr. david prezant is chief medical officer of new york city's fire department and lead study author. would you say that the strength of this association with cancer is mild, moderate or strong? >> i would say it's a moderately strong association. the biggest surprise was that cancer was increased. but that increase is real and now we need to address it. >> reporter: an increase in several different cancers was found, and some cancer experts insist that 38 extra cases could have been by chance. and it's too early to know for sure if 9/11 exposure is the cause. >> i would draw no definitive conclusion from it at this point. >> reporter: dr. al nougat studies the link between environment and cancer. >> one wouldn't expect to see an elevation in solid tumors so early. seven years is very short, usually it takes decades. normally we want to see elevations in specific cancers. you don't expect something to elevate multiple or all cancers. >> reporter: still, many families of first responders are convinced their loved ones' exposure after 9/11 caused their cancer. >> we found this kid. he w

dr. david prezant, called this pretty significant to me. i interviewed him about this specifically.isten to what he had to say. >> as we start seeing cancers we want to answer their question, is cancer increased. and i have to tell you that my initial bias was that for the first 10 or 15 years we would not see an increase. that's another reason why i think our findings are so strong. because i actually thought we would find the opposite. >> you were surprised. >> very much so. whether we can say that cancer is increased in other responders or area residents, we have no idea. this is a study about firefighters. their exposure is so unique. 85% of the exposed were present in the first 48 hours of the collapse when the exposure was massive. that is a very unique exposure. >> firefighters watching, they have the lingering question, why did i get this cancer and was it related to the dust. and you would say what? >> for most instances, it was world trade center-related. >> pretty remarkable to hear that, anderson. i mean, again what he's saying is something that a lot of people haven't b