Kandovan the next ‘Capadoccia’? – A potential public health issue for erionite related mesothelioma risk

Background:The Kandovan region in Iran is physically and geologically similar to the Cappadocian region in Turkey where fibrous zeolites, including erionite, have been found in volcanic tuffs. In some Cappodocian villages there is strong evidence that erionite, and possibly related minerals, are responsible for the high level of mesothelioma found there. So, although mesothelioma clusters have not been reported in Kandovan, it is a plausible hypothesis that many cases of mesothelioma in Iran may be due to naturally occurring fibrous zeolites.Methods: A detailed study of Iranian geology was made to determine similarities between the Kandovan region and Cappadocia, ‘inter-mountain zones’ in the Western US and Mexico. Areas where mesothelioma cases probably attributable to erionite exposure have been found. Results:Although there is a long history of asbestos use in Iran many cases of mesothelioma do not present with positive asbestos exposure histories. Since fibrous zeolites are so widespread, why have not more mesotheliomas attributable to them been found throughout Iran? Various possible reasons were explored including misdiagnosis, poor surveillance, a general lack of awareness that this tumor may be linked to mineral fibre exposure. There is also the analytical problem of identifying fibrous erionite in lung tissue.Conclusions:There is every reason to believe mesotheliomas due to fibrous zeolite including erionite will be found in Iran. The most likely places to find them are the villages that look very similar to those found in Cappadocia since these are based upon similar geological formations

Performance evaluation of a brackish water reverse osmosis pilot-plant desalination process under different operating conditions: Experimental study

YesThe Reverse Osmosis (RO) input parameters have key roles in mass transport and performance indicators. Several studies can be found in open literature. However, an experimental research on evaluating the brackish water RO input parameters influence on the performance metrics with justifying the interference between them via a robust model has not been addressed yet. This paper aims to design, construct, and experimentally evaluate the performance of a 50 m3/d RO pilot-plant to desalinate brackish water in Shahid Chamran University of Ahvaz, Iran. Water samples with various salinity ranging from 1000 to 5000 ppm were fed to a semi-permeable membrane under variable operating pressures from 5 to 13 bar. By evaluating permeate flux and brine flowrate, permeate and brine salinities, membrane water recovery, and salt rejection, some logical relations were derived. The results indicated that the performance of an RO unit is largely dependent on feed pressure and feed salinity. At a fixed feed concentration, an almost linear relationship was found to relate feed pressure and both permeate and brine flowrates. Statistically, it was found that 13 bar feed pressure results in a maximum salt rejection of 98.8% at a minimum permeate concentration of 12 ppm. Moreover, 73.3% reduction in permeate salinity and 30.8% increase in brine salinity are reported when feed pressure increases from 5 to 13 bar. Finally, it is concluded that the water transport coefficient is a function of feed pressure, salinity, and temperature, which is experimentally estimated to be 2.8552 L/(m2 h bar)