Epidemiology in Asbestos Cases Yes, there remain epidemiology questions even after all these years . Pharyngeal Cancer . Laryngeal Cancer . Esophageal Cancer . Stomach Cancer . Colorectal Cancer A Valuable Resource re Other Cancers Asbestos: Selected Cancers (NAS) • Pre-Trial Hearings . Articles read and relied upon . Dr. Schwartz and Colon Cancer Laryngeal Cancer . Largely related to drinking and smoking, like esophageal cancer. NAS Study does see a link between asbestos exposure and laryngeal cancer --- BUT . Related to asbestos --- 1 < RR <2 --- disease causation is more ambiguous Laryngeal Cancer Laryngeal Cancer Risk 1< RR <2 Present Absent Assuming RR=1.5 Exposure 6 4 Control 4 6 No disease Disease w/ Asbestos Disease w/ OR w/o Asbestos Exposure Control Among the 6 cases in exposure group, 4 cases will occur even without asbestos exposure Laryngeal Cancer 4/6 in Asbestos group will have Laryngeal cancer with or without Asbestos No disease Due to Asbestos Disease w/ Asbestos w/ or w/o Asbestos Disease w/ OR w/o Asbestos Exposure Control Attributable Risk = (6-4)/6 = 33.3% --- <50% CONCLUSION Chances of developing Laryngeal Cancer due to Asbestos v. Other Causes = (6-4)/6 = 33.3% <50% Lung Cancer . Many questions, many studies: . Smoking . Synergy between smoking and asbestos . Absence of asbestosis . Presence of plaques Smoking . Lung cancer without smoking? . Only Selikoff & Hammond/Selikoff. Many dangers from smoking including second hand smoke. RR lung cancer from smoking: . CPS I = 11.35 . CPS II = 22.36 Need for Asbestosis . Heuper (1955) . Kipen, Pulmonary Fibrosis in Asbestos Insulation Workers with Lung Cancer…, (1987) . Asbestosis found in 100% of cases. Helsinki -- Many opinions Mesothelioma Epidemiology Is there anything left to learn about mesothelioma causation? Can Chrysotile Asbestos Cause Mesothelioma at < 300 f-ml/yrs? . Liddell (1996) said “NO”. Auto mechanic studies . Plaintiff claims: . Vianna (case report) . Studies from China . The Balangero Mines studies . Piolatto (1990) . Mirabelli (2008) . Balangeroite Mesothelioma Epi Questions . What levels of chrysotile have been shown epidemiologically to cause mesothelioma? . What about peritoneal meso? . What low levels of asbestos generally have been epidemiologically shown to cause mesothelioma? . Is there any epidemiology to support synergy between amphiboles and chrysotile? (Hammar idea) A Tale of Two Mines Thetford Mines - Quebec Balangero Mine - Italy Thorough cohort study over • Small cohort study many years supplemented by some case reports The Balangero Mine Piolatto study Mirabelli report Can Any Asbestos Cause Mesothelioma at < 1 f/cc-yr? . No Epidemiology has shown that . Case reports - Vianna . Hillerdal (1999) – anecdotes. Synergy Between Chrysotile and Amphiboles? . Dr. Hammar contention . Hessel, Mesothelioma Among Brake Mechanics…., (2004) – refutes the contention. .