<prompt> Diffuse mesothelioma is seen with: PGI Nov 2009AsbestosArsenicTobacco useT.B  <response>: Ans: A Asbestos Ref Harrison 17thl 613-14: Park 23rd307, 20th712Mesotheliomas both pleural and peritoneal, are associated with qsbestos exposure. In contrast to lung cancers, these tumors do not appear to be associated with smoking. Relatively short-term asbestos exposures of 1-2 years or less, occurring up to 40years in the past, have been associated with the development of mesotheliomas- Harrison 17th1613Mesothelioma has been shown to have a strong association with crocidolite varietyof asbestos -Park 20th712Table Harrison: Categories of Occupational Exposure and Associated Respiratory ConditionsOccupationalExposuresNature of Respiratory ResponsesCommentInorganic Dusts Asbestos: mining, processing, construction, ship repairFibrosis asbes- tosis, pleural disease, cancer, mesothelioma0Virtually all new mining and construction with asbestos done in developing countriesSilica: mining, stone cutting, sandblasting, quarryingFibrosis silicosis, PMF, cancer, silicotubereulo- sisP; CO PDImproved protection in United States, persistent risk in developing countriesCoal dust: miningFibrosis coal workers pneumoconiosisQ, PMF. COPDRisk dropping in United States, increasing where new mines openBeryllium: processing alloys for high- tech industriesAcute pneumonitis, chronic granulomatous diseaseQ, lung cancer highly suspectRisk in high-tech industries persistsOther metals: aluminum, chromium, cobalt, nickel, titanium, tungsten carbide, or hand metal contains cobaltWide variety of conditions from acute pneumonitis to lung cancer and asthmaNew diseases appear with new process developmentOrganic Dusts Cotton dust: milling, processingByssinosisP an asthma-like syndromeQ, chronic bronchitis, COPDIncreasing risk in developing countries with drop in United States as jobs shift overseasGrain dust: elevator agents, dock workers, milling, bakersAsthma, chronic bronchitis, COPDRisk shifting more to migrant labor poolOther agricultural dusts: fungal spores, vegetable products, insect fragments, animal dander, bird and rodent feces, endotoxins, microorganisms, pollensHypersensitivity pneumonitis farmers lung Q, asthma, chronic bronchitisImportant in migrant tabor pool but also resulting from in-home exposures 