Kingdom of Saudi Arabia and the Gulf region are frequently exposed to major dust storms and anthropogenic emissions from rapidly growing industrial activities that affect aerosols optical and physical characteristics. This paper integrates observations from space-borne sensors namely MODIS and CALIPSO, together with AERONET ground observations to examine eight years aerosols characteristics during the (March–May) season of 2003 to 2010 over Saudi Arabia. Aerosol analysis from the interdependent data assessment show comparable aerosols characteristics over the eight year period with higher aerosols mean optical depths over enhanced dust load region, (46–50°E, 25–29°N), during March–May of 2009 and 2010. The mean angstrom exponent during March–May 2003 to 2008 was found 17

Basin analysis (the reconstruction of the dynamics and history of sedimentary basins) has entered a quantitative stage that requires analytical lithologic data. These data must include geologic parameters that describe the characteristics of sediments and the diagenetic changes that they undergo through time. Diagenesis is controlled by eight geologic parameters: sediment composition, temperature history, rate of accommodation (subsidence + sea-level changes + sediment compaction), rate of sediment accumulation, age (time that sediments have been exposed to other variables), internal sediment-body architecture (sedimentary texture and structure), sediment-body external geometry, and fluid chemistry and flow history. Tectonic and paleogeographic settings determine the primary compositions of both chemical and siliciclastic sediments. Siliciclastic provenances are reflected by the mineralogy of sandstones. The source or sources of sediment in sandstone units within genetic sequences and the contribution of each source need to be evaluated in terms of quantitative effects on the various diagenetic styles observed. With the use of modern settings as partial analogues, stratigraphic, sedimentologic, and petrographic data can be used to reconstruct sandstone architecture and to draw inferences about original pore fluid chemistry. Subsidence histories, isotopic signatures, trace element compositions, and fluid inclusion studies combined with petrographic observations can be used to set constraints on the geologic parameters for sandstone bodies within a time-temperature-basin setting framework. As more insight is gained into the reaction kinetics within specific paleotectonic and depositional settings, diagenetic modeling will become increasingly more quantitative and precise.

Asbestos causes malignant transformation of primary human mesothelial cells (HM), leading to mesothelioma. The mechanisms of asbestos carcinogenesis remain enigmatic, as exposure to asbestos induces HM death. However, some asbestos-exposed HM escape cell death, accumulate DNA damage, and may become transformed. We previously demonstrated that, upon asbestos exposure, HM and reactive macrophages releases the high mobility group box 1 (HMGB1) protein that becomes detectable in the tissues near asbestos deposits where HMGB1 triggers chronic inflammation. HMGB1 is also detectable in the sera of asbestos-exposed individuals and mice. Searching for additional biomarkers, we found higher levels of the autophagy marker ATG5 in sera from asbestos-exposed individuals compared to unexposed controls. As we investigated the mechanisms underlying this finding, we discovered that the release of HMGB1 upon asbestos exposure promoted autophagy, allowing a higher fraction of HM to survive asbestos exposure. HMGB1 silencing inhibited autophagy and increased asbestos-induced HM death, thereby decreasing asbestos-induced HM transformation. We demonstrate that autophagy was induced by the cytoplasmic and extracellular fractions of HMGB1 via the engagement of the RAGE receptor and Beclin 1 pathway, while nuclear HMGB1 did not participate in this process. We validated our findings in a novel unique mesothelial conditional HMGB1-knockout (HMGB1-cKO) mouse model. Compared to HMGB1 wild-type mice, mesothelial cells from HMGB1-cKO mice showed significantly reduced autophagy and increased cell death. Autophagy inhibitors chloroquine and desmethylclomipramine increased cell death and reduced asbestos-driven foci formation. In summary, HMGB1 released upon asbestos exposure induces autophagy, promoting HM survival and malignant transformation.

Three outcrops of the Silurian Sharawra Formation at its type locality in Old Qusaiba Village in Central Saudi Arabia were studied for lithofacies distribution, petrographical, and geochemical characteristics. The outcrops were logged and nine different lithofacies were identified in the field. Petrographic analysis shows the Sharawra Formation to be mainly subarkosic associated with increasing mica content near to its contact with the underlying Qusaiba Shale Formation. Major and trace element geochemistry indicates that the sediments of the formation were deposited in a passive continental margin. The source area discriminating plots reveal acidic or felsic rocks such as granites as the probable provenance of the Sharawra sediments. The Chemical Index of Alteration (CIA) and Chemical Index of Weathering (CIW) indicate a moderate degree of weathering in the source area of these Silurian sediments. This study provides a baseline for future characterization studies of Paleozoic siliciclastic formations in Saudi Arabia and neighbouring countries.

This chapter deals with the crystal structure of regulated and unregulated mineral fibres. The aim is to provide readers, both specialists and researchers broadly interested in environmental problems, with up-to-date information on a topic that is expanding daily. The chapter describes specifically the structure of the fibrous modification whenever available and outlines possible differences from the corresponding prismatic variety. Details of the experimental techniques used for structure determination/refinement are reported also, if appropriate, to outline the experimental difficulties faced due to the small dimensions, sensitivity and chemical complexity of mineral fibres.

Erionite belonging to the zeolite family is a human health-hazard, since it was demonstrated to be carcinogenic. Conversely, offretite family zeolites were suspected carcinogenic. Mineralogical, morphological, chemical, and surface characterizations were performed on two erionites (GF1, MD8) and one offretite (BV12) fibrous samples and, for comparison, one scolecite (SCI) sample. The specific surface area analysis indicated a larger availability of surface sites for the adsorption onto GFI, while SCI shows the lowest one and the presence of large pores in the poorly fibrous zeolite aggregates. Selected spin probes revealed a high adsorption capacity of GFI compared to the other zeolites, but the polar/charged interacting sites were well distributed, intercalated by less polar sites (Si-O-Si). MD8 surface is less homogeneous and the polar/charged sites are more interacting and closer to each other compared to GFI. The interacting ability of BV12 surface is much lower than that found for GF1 and MD8 and the probes are trapped in small pores into the fibrous aggregates. In comparison with the other zeolites, the non-carcinogenic SCI shows a poor interacting ability and a lower surface polarity. These results helped to clarify the chemical properties and the surface interacting ability of these zeolite fibers which may be related to their carcinogenicity. (C) 2015 Elsevier B.V. All rights reserved.

Exposure of humans to erionite fibers of suitable morphology and dimension has been unambiguously linked to the occurrence of malignant mesothelioma. For this reason, a morphological, morphometrical, mineralogical, and chemical investigation was performed on two representative samples of potential carcinogenic, fibrous erionite from Lessini Mounts, northeastern (NE) Italy, which has not apparently been examined previously. The first sample is erionite-Ca with an extremely fibrous, hair-like and flexible appearance, and growth in intimate association with levyne. The second sample is erionite-Ca with prismatic to acicular crystals and rigid behavior, enriched in K+ and Ca2+ extra-framework cations. Although erionite is a nominally Fe-free phase, iron (Fe) was detected in low amounts in all the analyzed crystals. In both the investigated samples, erionite is present as individual fibers of respirable size. Considering that the toxicity and carcinogenic potential of erionite is associated with its size parameters, together with its in vivo durability and high surface area, most of the investigated fibers may also be potentially carcinogenic. The presence of erionite in extensively quarried and largely employed volcanic rocks, suggesting the need for detailed health-based studies in the region.

On November 9 and 10, 2015, the International Conference on Mesothelioma in Populations Exposed to Naturally Occurring Asbestiform Fibers was held at the University of Hawaii Cancer Center in Honolulu, Hawaii. The meeting was cosponsored by the International Association for the Study of Lung Cancer, and the agenda was designed with significant input from staff at the U.S. National Cancer Institute and National Institute of Environmental Health Sciences. A multidisciplinary group of participants presented updates reflecting a range of disciplinary perspectives, including mineralogy, geology, epidemiology, toxicology, biochemistry, molecular biology, genetics, public health, and clinical oncology. The group identified knowledge gaps that are barriers to preventing and treating malignant mesothelioma (MM) and the required next steps to address barriers. This manuscript reports the group's efforts and focus on strategies to limit risk to the population and reduce the incidence of MM. Four main topics were explored: genetic risk, environmental exposure, biomarkers, and clinical interventions. Genetics plays a critical role in MM when the disease occurs in carriers of germline BRCA1 associated protein 1 mutations. Moreover, it appears likely that, in addition to BRCA1 associated protein 1, other yet unknown genetic variants may also influence the individual risk for development of MM, especially after exposure to asbestos and related mineral fibers. MM is an almost entirely preventable malignancy as it is most often caused by exposure to commercial asbestos or mineral fibers with asbestos-like health effects, such as erionite. In the past in North America and in Europe, the most prominent source of exposure was related to occupation. Present regulations have reduced occupational exposure in these countries; however, some people continue to be exposed to previously installed asbestos in older construction and other settings. Moreover, an increasing number of people are being exposed in rural areas that contain noncommercial asbestos, erionite, and other mineral fibers in soil or rock (termed naturally occurring asbestos [NOA]) and are being developed. Public health authorities, scientists, residents, and other affected groups must work together in the areas where exposure to asbestos, including NOA, has been documented in the environment to mitigate or reduce this exposure. Although a blood biomarker validated to be effective for use in screening and identifying MM at an early stage in asbestos/NOA-exposed populations is not currently available, novel biomarkers presented at the meeting, such as high mobility group box 1 and fibulin-3, are promising. There was general agreement that current treatment for MM, which is based on surgery and standard chemotherapy, has a modest effect on the overall survival (OS), which remains dismal. Additionally, although much needed novel therapeutic approaches for MM are being developed and explored in clinical trials, there is a critical need to invest in prevention research, in which there is a great opportunity to reduce the incidence and mortality from MM.

Similar to asbestos fibers, nonregulated mineral fibers can cause malignant mesothelioma (MM). Recently, increased proportions of women and young individuals with MM were identified in southern Nevada, suggesting that environmental exposure to carcinogenic fibers was causing the development of MM. Palygorskite, a fibrous silicate mineral with a history of possible carcinogenicity, is abundant in southern Nevada. In this study, our aim was to determine whether palygorskite was contributing to the development of MM in southern Nevada. While palygorskite, in vitro, displayed some cytotoxicity toward primary human mesothelial (HM) cells and reduced their viability, the effects were roughly half of those observed when using similar amounts of crocidolite asbestos. No Balb/c (0/19) or MexTAg (0/18) mice injected with palygorskite developed MM, while 3/16 Balb/c and 13/14 MexTAg mice injected with crocidolite did. Lack of MM development was associated with a decreased acute inflammatory response, as injection of palygorskite resulted in lower percentages of macrophages (p = .006) and neutrophils (p = .02) in the peritoneal cavity 3 d after exposure compared to injection of crocidolite. Additionally, compared to mice injected with crocidolite, palygorskite-injected mice had lower percentages of M2 (tumor-promoting) macrophages (p = .008) in their peritoneal cavities when exposed to fiber for several weeks. Our study indicates that palygorskite found in the environment in southern Nevada does not cause MM in mice, seemingly because palygorskite, in vivo, fails to elicit inflammation that is associated with MM development. Therefore, palygorskite is not a likely contributor to the MM cases observed in southern Nevada.

In the fluoropolymers family, one of the newest members is the terpolymer of tetrafluoroethylene, hexafluoropropylene, and vinylidene fluoride (THV). There are scarce data on THV, and therefore it is necessary to study different properties of THV. In the current research, the detailed surface morphology and water wettability of electrospun microfibers prepared from THV/ethyl acetate solutions in the pure state and with the addition of Wyoming-type low-magnesium montmorillonite are discussed. The morphology of the terpolymer microfibers changes as a function of the polymer solution concentration. For the same polymer concentration, changing the applied voltage in microfiber formation does not alter the morphology. The addition of hydrophilic montmorillonite into the THV solution does not modify the rougher hydrophobic nature and morphology of the final electrospun fiber surfaces. Water contact angle measurements show that both in the pure state and in the mixture of montmorillonite, THV electrospun microfibers exhibit “near superhydrophobic” characteristics with contact angles as high as 145°.

Introduction: Naturally occurring asbestos (NOA) and other fibrous mineral exposures have been associated with disease throughout the world. This is especially true of erionite which has caused unprecedented rates of malignant mesothelioma (MM) mortality in several Turkish villages. Erionite deposits are also present in at least 12 U.S. states, and gravel from these deposits has been widely used for roads around Dunn County, North Dakota (ND). An understanding of the environmental exposures, toxicology, and health risks from fibrous minerals is vital to identifying these hazards and protecting public health in the face of rapid urbanization of previously undisturbed geologies. Methods: We evaluated airborne exposures and the physical and chemical properties of erionite exposures in Turkish villages with high MM rates compared to erionite exposures along roads and in vehicles and buildings in ND. Outdoor asbestos exposures collected during extensive air sampling in Libby, Montana (MT), were also compared for additional reference. Results: Airborne erionite concentrations measured in ND along roadsides, indoors, and inside vehicles, including school buses, equaled or exceeded concentrations measured in Boyali, Turkey, where 6.25% of all deaths are caused by MM. With the exception of outdoor samples along roadsides, ND concentrations were lower than those measured in Turkish villages with MM mortality ranging from 20 to 50%. The physical and chemical properties of erionite from Turkey and ND were very similar. Exposures in ND also overlapped with those observed in Libby, MT, during sampling designed to mimic activities such as raking and digging, etc. Discussion: Management of these hazardous exposures varies widely. Our findings indicate that cogent population surveillance and preventive measures to control exposures associated with erionite and NOA rich geologies should be undertaken in the U.S. and elsewhere to protect public health.

We propose a methodology as a possible standard approach for micropaleontological studies addressed to detect test microstructure and the chemical/mineralogical composition of grains used by agglutinated foraminifera. Themethodology was tested on over 200 specimens of fossil agglutinated foraminifera, mostly belonging to the textulariid group, collected from Cenozoic successions of theMediterranean region. The approach assesses the internal morphological and compositional features of agglutinated foraminifera by Scanning ElectronMicroscopy (SEM) and Energy Dispersive Spectroscopy (EDS) analyses, performed on representative specimens that were embedded in epoxy resin and subsequently sectioned and polished.With respect to similar techniques that perform SEM and EDS analyses mostly on the agglutinated wall surface of free specimens or broken tests, this methodology provides the preparation of cross sections of isolated individuals. The use of cross sections has the advantages of: (i) documenting the internal chamber arrangement and other morphological elements (such as alcoves or canaliculi), even considering if the recognized features remain constant or change during ontogeny; (ii) measuring the testwall thickness and the grain distributionwithin the testwalls; (iii) detecting the chemical composition of the agglutinated grains and the cement in order to highlight mineralogical grain selectivity and arrangement; (iv) studying the agglutinated grains in their original position within the test wall and during test growth; and (v) the elemental compositional data collected from polished sections are more accurate than those collected on the rough surface of specimens.

Exposure to asbestos or erionite is associated with malignant mesothelioma (MM) and other diseases. Micro‐Raman spectroscopy and Variable Pressure Scanning Electron Microscopy/Energy Dispersive Spectroscopy were used to identify mineral fibers in histological sections of various tissues taken from mice injected with crocidolite asbestos and erionite fibers. Routine diagnostic histopathological slides of biopsies from erionite‐exposed MM patients from Turkey were also analyzed. We show here that micro‐Raman spectroscopy easily permits the recording of distinct Raman patterns of both crocidolite and erionite fibers, in both murine tissues and in human biopsies. The described findings provide a new powerful and non‐destructive tool to determine the type of fiber exposure in patients with MM and other mineral fiber‐associated diseases. Copyright © 2013 John Wiley & Sons, Ltd.

New compositional data are presented for a suite of basaltic andesite to rhyolite flows from the flanks of the Pliocene-Quaternary Mt. Erciyes stratovolcano in Central Anatolia, Turkey. The samples are all part of the most recent (<0.9 Ma) New Erciyes eruptive phase. Temperatures estimated from FeTi-oxides vary from similar to 1000 degrees C in the andesites to similar to 820 degrees C in the rhyolites, while the dacites preserve a very broad temperature range (similar to 620 degrees C-1020 degrees C), consistent with textural and mineral chemistry evidence for their hybrid nature. Oxygen fugacity is about NNO + 1 for most samples. The whole rock compositional data, in conjunction with published data, reveal two distinct trends, one formed by the mafic samples (basalts to basaltic andesites) and one by the silicic samples (andesites-dacites-rhyolites). All Erciyes samples plot above the MORB-OIB array on a Nb/Yb-Th/Yb plot, consistent with involvement of subduction-modified mantle, and their low MREE/HREE ratios imply melting of garnet-free mantle. Ratios of incompatible trace elements demonstrate that the basaltic andesite flows are not related to the basalt flows by closed-system fractional crystallization, but instead are derived from a more enriched mantle source, given their higher La/Sm and lower Zr/Nb. The silicic lavas all have higher Th/Nb than the mafic samples, indicating more extensive crustal assimilation. The silicic lavas show linear compositional trends for major elements and most trace elements for SiO2 contents between 56 wt.% and 72 wt.% that are attributed to mixing processes, consistent with textural observations and mineral data particularly in the intermediate dacite flows (two distinct plagioclase phenocryst populations - clear An(33-53) cores vs. sieve-textured cores of An(59-80); wide compositional range for orthopyroxene phenocrysts - Mg# from 63 to 90). We infer that basaltic melts of a heterogeneous, shallow mantle source ponded in the mid- to lower-crust and underwent variable differentiation accompanied by crustal assimilation to form more evolved melt compositions with SiO2>similar to 55 wt.%. These melts ascended to shallower crustal levels (4-10 km based on amphibole geobarometry) where mixing of diverse melts and entrained crystals gives rise to the linear mixing trends shown by the erupted andesite-dacite-rhyolite lavas. (C) 2013 Elsevier B.V. All rights reserved.

Malignant mesothelioma (MM) is a neoplasm arising from mesothelial cells lining the pleural, peritoneal, and pericardial cavities. Over 20 million people in the US are at risk of developing MM due to asbestos exposure. MM mortality rates are estimated to increase by 5–10% per year in most industrialized countries until about 2020. The incidence of MM in men has continued to rise during the past 50 years, while the incidence in women appears largely unchanged. It is estimated that about 50–80% of pleural MM in men and 20–30% in women developed in individuals whose history indicates asbestos exposure(s) above that expected from most background settings. While rare for women, about 30% of peritoneal mesothelioma in men has been associated with exposure to asbestos. Erionite is a potent carcinogenic mineral fiber capable of causing both pleural and peritoneal MM. Since erionite is considerably less widespread than asbestos, the number of MM cases associated with erionite exposure is smaller. Asbestos induces DNA alterations mostly by inducing mesothelial cells and reactive macrophages to secrete mutagenic oxygen and nitrogen species. In addition, asbestos carcinogenesis is linked to the chronic inflammatory process caused by the deposition of a sufficient number of asbestos fibers and the consequent release of pro‐inflammatory molecules, especially HMGB‐1, the master switch that starts the inflammatory process, and TNF‐alpha by macrophages and mesothelial cells. Genetic predisposition, radiation exposure and viral infection are co‐factors that can alone or together with asbestos and erionite cause MM. J. Cell. Physiol. 227: 44–58, 2012. © 2011 Wiley Periodicals, Inc.

The physical and chemical characteristics of kaolinite (kaolin) may be variable, and minor amounts of other clay minerals, nonclay minerals, and other impurities may affect the properties of kaolinites. Thus specific technical properties of pharmaceutical grade kaolinites become very important because these clays are used in medical applications, e.g., as pharmaceutical excipients, and will be consumed by humans. Seven pharmaceutical grade kaolinite specimens were used in this study: K1004, KA105, 2242-01, K2-500, Acros, Acros-mono, and KX0007-1. In addition, two kaolinites from the Clay Minerals Society Source Clays, KGa-1b and KGa-2, were used for comparison purposes. The Acros-mono and 2242-01 kaolinites contained minor amounts of illite, which was demonstrated both compositionally and structurally by using inductively coupled plasma spectroscopy and powder X-ray diffraction. The KX0007-1 kaolinite powder was found to be heavily contaminated with quartz, cristobalite, and alunite. Crystal structure computations also showed excess Si in its tetrahedral site, and the mineral no longer has the typical kaolinite crystal structure. These widely-used industrial standards should be quantitatively characterized morphologically, compositionally, and structurally. Results of the mineralogical characteristics should be clearly labeled on the pharmaceutical grade kaolinites and reported to the relevant regulatory agencies.