Primary peritoneal mesothelioma is a rare disease withan annual incidence of only one case per million inthe US. In 1960, the clear relationship betweenoccupational and environmental crocidolide exposureand diffuse pleural mesothelioma was demonstrated.A recent study from Norway has also shown a highincidence of mesothelioma and a high ratio ofmesothelioma to lung cancer among asbestos andcement workers. No peritoneal mesothelioma wasfound. The ratio of mesothelioma to lung cancercases was 1: 2 for the total cohort. Rare cases ofmesothelioma have been associated with radiationexposure, with studies in rats supporting the notionthat radiation exposure can cause mesothelioma. Itseems safe to state that intensive radiation exposurecan cause mesothelioma; however, the overallnumber of mesotheliomas caused by radiation isprobably small. There is some evidence that SimianVirus (SV 40) and asbestos might be carcinogens inhuman mesothelial cells in tissue culture. Genetic anderionite may co-operate in causing mesothelioma inthe Cappadocian region of Turkey. Mesotheliomamay be a cancer in which genetics, radiation, virusesand erionite interact to cause malignancy.