11January 25, 2006: IAP 2006: 12.091 January 25, 2006: IAP 2006: 12.091 Session 5: P. ILASession 5: P. ILAMEDICAL MEDICAL GEOLOGY/GEOCHEMISTRY:GEOLOGY/GEOCHEMISTRY:An ExposureAn ExposurePILLALAMARRI ILAPILLALAMARRI ILAEarth Atmospheric & Planetary SciencesEarth Atmospheric & Planetary SciencesNeutron Activation Analysis LaboratoryNeutron Activation Analysis LaboratoryMassachusetts Institute of TechnologyMassachusetts Institute of TechnologyCambridge, MA 02139Cambridge, MA 02139IAP 2006: 12.091 Credit Course: January 9 IAP 2006: 12.091 Credit Course: January 9 --25, 200625, 2006Session 5 Session 5 --January 25, 2006January 25, 2006January25,2006:IAP2006:12.091Session5:P.ILA2Session5January25,2006ObjectiveDustStorms– HealthEffectsReview&ConclusionsStudentsPresentationsonSelectedElementsStudentsReportsReviewQuizdue– January30,2006.January 25, 2006: IAP 2006: 12.091 3Sources:Natural processes:• Volcanic eruptions• Wind erosion/deflation of arid and semi-arid lands• Trans-oceanic dust transportAnthropogenic:• Mining• Detonations• Incinerations• Industrial activities• AccidentsCosmogenicDusts and AerosolsJanuary 25, 2006: IAP 2006: 12.091 4Natural Processes• Volcanic eruptions• Wind erosion/deflation of arid and semi-arid lands with sparse vegetation cover create and propagate mineral dust aerosols.Trans-oceanic dust transport.January 25, 2006: IAP 2006: 12.091 5Volcanic EruptionsTephra - volcanic rock and glass fragments.Volcano eruption may sometimes eject rock fragments into the atmosphere. This material is known as tephra. Blocks and bombs are the largest pieces of tephra(greater than 64 mm).January 25, 2006: IAP 2006: 12.091 6Health effects of tephra dispersal• Mucous membrane irritation• Silicosis (Due to Calcium FluoroSilicate CaSiF6).• Effects of absorbed toxins • Silicotic nodules lodging in the lung tissue damaging the surrounding alveoli of the lung.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA7January 25, 2006: IAP 2006: 12.091 8Health effects of volcanic gas emissions• CO2Asphyxiation – possible death of humans and animals.• HF2and HCl Irritant gases –Mucous membrane irritation.Skin burns.Respiratory problems.• SO2Environmental effect by acid rainAsthmatic effects• H2S Noxious asphyxiant7 μg/m3- rotten egg smell15,000 μg/m3– eye irritation480,000 μg/m3– risk of pulmonary oedema1,500,000 μg/m3- lethalJanuary 25, 2006: IAP 2006: 12.091 Session 5: P. ILA9Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 10Dusts - Wind erosion• Mineral aerosols: 1-2 b metric tons/year (comprise half of total aerosols in troposhere from natural and anthropogenic sources)• Play role in current climatic variabilities.• Play role in ecosystem dynamics.Examples:Sahara desert-(Northern Africa) Sahel Africa is a stretch of land that includes countries like Ethiopia, Eritrea, Djibouti, and Somalia. This stretch is a transition zone between the arid Sahara to the north and wet tropical area to the south. Example: some affected areas are, such as, Chad, Senegal, Mauritania, Mali, Niger, etc. Gobi desert - (Mongolia-Central Asia)Example: affected area Taklamakan – (China).January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA11Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA12Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA13BeneficialCourtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA14Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA15Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA16Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA17Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA18Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA19Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA20Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 21Anthropogenic• Mining• Detonations• Incinerations• Industrial activities• AccidentsJanuary 25, 2006: IAP 2006: 12.091 22The Health Effects of Dusts• Health hazards of mining are well known for a long time: General effects of industrial/commercial asbestos Asbestosis (mining) Silicosis (hard rock mining) Black lung (coal mining)• New issues and problems are arising: Effects of trace asbestos in other rocks and industrial products Valley Fever Trans-oceanic dust transport Global Climatic ChangeJanuary 25, 2006: IAP 2006: 12.091 23Occupational Hazards• Asbestos mining and processing• Coal mining• Hard rock mining• Ore processing• Farming• Power plant operationJanuary 25, 2006: IAP 2006: 12.091 24New Problems…• Trace Element Exposure – As, F, Hg, Zn, …• Organics: VOCs (Volatile aromatic Compounds – paints etc)MTBEs (Methyl tert butyl ether)PAHs (Polycyclic aromatic hydrocarbons – coal tar)• Radionuclides: Radon, radium and Uranium, …• Microbes and Pathogens:West Nile encephalitis, Hantavirus, Plague, Lyme, …January 25, 2006: IAP 2006: 12.091 25New Problems …• VOC - Volatile Organic Compounds -Trichloroethylene, methyl tert butylether(MTBE - paints• PAH - Polycyclic Aromatic Hydrocarbons These PAHs are benzo(a)pyrene, benz(a)anathracene, benzo(k)flouranthene, indeno(1,2,3-c,d)pyrene and chrysene. In application, this proposed procedure would regard any given air level obtained for a "PAH of concern" to originate from a standard mixture of coal tar pitch (CTP).January 25, 2006: IAP 2006: 12.091 26New Problems…Delayed/chronic health effects:• Respiration• Skin• Cancerous effectsJanuary 25, 2006: IAP 2006: 12.091 Session 5: P. ILA27January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA28Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA29January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA30Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA31Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA32Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA33Courtesy of USGS.January 25, 2006: IAP 2006: 12.091 Session 5: P. ILA34Mining /SmeltingOccupational hazards: Toxic gas inhalations Pressure effects Thermal injury Physical