Geochemistry of the Jurassic and Upper Cretaceous shales from the Molango Region, Hidalgo, eastern Mexico: Implications for source-area weathering, provenance, and tectonic setting

This study focuses on the Jurassic (Huayacocotla and Pimienta Formations) and Upper Cretaceous (Mendez Formation) shales from the Molango Region, Hidalgo, Mexico. In this article, we discuss the mineralogy, major, and trace element geochemistry of the Mesozoic shales of Mexico. The goal of this study is to constrain the provenance of the shales, which belong to two different periods of the Mesozoic Era and to understand the weathering conditions and tectonic environments of the source region

Geochemistry of the Madawara Igneous Complex, BundelkhandCraton, Central India: Implications for PGE Metallogeny

The southern part of the Bundelkhand cratoncontains a series of a E-W trending mafic and ultramaficrocks, about 40 km in length and 2–4 km wide, that occuras intrusions within the Bundelkhand Gneissic Complex(BnGC). They are confined between the Madawara-Karitoran and Sonrai-Girar shear zones. Dunite, harzburgite,lherzolite and websterite are the commonly occurringultramafic rocks that have high MgO, Ni, Cr, PGE andlow Al2O3, CaO, K2O, TiO2 and V contents, and showsperidotitic affinity. A distinct trend of crystallization fromperidotite to komatiitic basalt has been inferred from geochemicalplots, which also indicates the occurrence ofat least two varieties among the ultramafic suite of theMadawara ultramafic complex, namely, Group I comprisingdunite, spinel peridotite, harzburgite and lherzolite,and Group II consisting of pyroxenite, websterite andolivine websterite. In several places, the rocks of Group IIhave an intrusive relationship with Group I, and are relativelyenriched in total platinum group elements (PGE ~300 ppb). The discrimination diagrams suggest that thePGE are enriched in low sulphur-fugacity source magma atmoderate to deeper depths by high degree of partial meltingof the mantle

New REE and trace element data on two kimberlitic reference materials by ICP-MS

Data on thirty-four minor and trace elements including all rare earth elements (REE) are reported for two kimberlitic international reference materials (SARM-39, MINTEK, RSA and MY-4, IGEM, Russia) by inductively coupled plasma-mass spectrometry (ICP-MS), some of them for the first time. Four digestion techniques (open acid, closed vessel acid, microwave and lithium metaborate fusion digestion) were used for the decomposition of samples for analysis by ICP-MS. Three other reference materials (USGS BHVO-1, CRPG BR-1 and ANRT UB-N) were analysed simultaneously using the same analytical methodology to assess the precision and accuracy of the determinations. The data obtained in this study compare well with working values wherever such values are available for comparison. Though open acid digestion was found to be very rapid, effective and convenient for the determination of several trace elements in kimberlitic samples, recoveries for heavy rare earth elements (HREE) were lower than the respective recoveries obtained by the other decomposition techniques used. The precision obtained was better than ± 6% RSD in the majority of cases with comparable accuracy. Chondrite-normalised plots of each RM for all the digestion techniques were smooth. The new data reported on the two kimberlitic reference materials make these samples useful for future geochemical studies of kimberlitic rocks

Determination of Boron, Phosphorus, and Molybdenum Content in Biosludge Samples by Microwave Plasma Atomic Emission Spectrometry (MP-AES)

A novel analytical method for accurate determination of boron (B), phosphorous (P), and molybdenum (Mo) content in biosludge samples based on a relatively recent analytical technique, microwave plasma atomic emission spectrometry (MP-AES), is developed in the present work. Microwave assisted acid digestion method is utilized to extract B, P, and Mo from biosludge. To demonstrate the reliability and accuracy of the present MP-AES method, its results are compared with those obtained using two well-established techniques, i.e., flame atomic absorption spectrometry (FAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES). Matrix variation in the MP-AES technique is found to result in minimal changes. Precision and accuracy of the developed method are demonstrated using replicate analyses of certified sewage sludge reference material, EnviroMAT (BE-1). The limit of quantification and detection of B, P, and Mo in the extracts are determined; the linear regression coefficient was greater than 0.998 for all the three techniques. Analytical wavelengths are selected according to the sensitivity and interference effects. The results obtained in this work demonstrate the potential of MP-AES technique for the determination of B, P, and Mo content in biosludge, which achieved lower detection limits, higher accuracy, and better reproducibility as compared to other techniques

Micronutrient mineral content of the fruiting bodies of Australian cultivated Agaricus bisporus white button mushrooms

Agaricus bisporus white button mushrooms (WBM) obtained from two farms were analyzed using inductively coupled plasma-mass spectrometer (ICP-MS) for minerals (Na, K, Mg, Ca, Mn, Fe, Cu, Zn, Se, Mo, Co, Cr, Pb, Cd, Si, B and V), and for the capacity to provide a dietary source of selected minerals (Na, K, Mg, Ca, Mn, Fe, Cu, Zn, Se, Mo and B). WBM contained Cu at levels of >30%, Se at levels >13% and Mo at levels of 6.4-10% of daily Required Dietary Intake (RDI) based on average values for adults as defined by Australian National Health and Medical Research Council (NHMRC). Boron (B) was found in the range of 72.4-1298.7. μg per 100 g serving. While the RDI for B has not been defined by National Health and Medical Research Council (NH&MRC), WBM contained on average >20% of RDI as defined by National Academy of Sciences (NAS). WBM contained on average 6.1% for Na, 3.4% for K, 4.1% for Mg and 0.7% for Ca daily RDI, all of which were nutritionally insignificant. Mn was found at relatively high concentrations ranging from 76.3 to 210.7. μg/100 g serving. When defined as % of daily RDI (NAS), it was considered nutritionally insignificant with values ranging from 1.9% to 3.9%. Accumulation of toxic heavy metals such as Pb and Cd was found in WBM (14.4-61.6. μg/100 g for Pb, and 0.2-2.6. μg/100 g for Cd, respectively) but the levels were below the safety limits defined by FAO/WHO for weekly intake. Both compost and casing contained high levels of minerals, and are the likely sources of mineral elements in WBM. While there were variations in mineral contents of WBM harvested from 1st, 2nd and 3rd flushes in the two farms, the differences were not statistically significant. Taken together, the results showed that A. bisporus white button mushroom can provide significant contribution to the daily requirements of several minerals from the point of view of human nutrition, and in particular, Cu, Se, Mo and B

Emerging contaminants: analysis, aquatic compartments and water pollution

International audienceOver the past two decades, the presence of so-called emerging contaminants in various environmental compartments around the world, such as water, sediments, soils and atmosphere, and in a wide variety of consumer products has become a major concern for society, public health authorities, industry (namely food industry and water sector) and the agricultural sector. Some of these substances are endocrine disruptors and others are proven carcinogens and mutagens. In particular, there is a growing concern about the presence of emerging contaminants in water resources.The list of substances and products is particularly long: pesticides, pharmaceuti-cals, drugs of abuse (including licit and illicit drugs), cosmetics, personal care prod-ucts, surfactants, cleaning products, industrial formulations and chemicals, food additives, food packaging, metalloids, rare earth elements, nanomaterials, micro-plastics and pathogens. Most of these substances are found not only in domestic wastewater and industrial discharges, but also in surface and ground water, and consequently in drinking water and food sources. Therefore, emerging contami-nants entering the aquatic compartment may cause known, unknown or suspected adverse effects on the ecosystems and/or human health. Many molecules have been classified in recent years as priority or priority hazardous substances, and thus, the industrial world and the municipal wastewater treatment plants are particularly con-cerned by the release of these substances by virtue of increasingly strict regulations. However, existing conventional municipal wastewater treatment plants and drinking water treatment plants were not designed for eliminating these new contaminants. In addition, most emerging contaminants are not yet routinely monitored either in industrial discharges or in the environment. From an academic point of view, emerging substances are also of great interest to the scientific community and receive special attention. The areas of research concern not only their effects on human health and their impact on environment, but also their sources, analysis and fate in the environment, as well as their remediation. Indeed, their behavior in the environ-ment and their effects on all living organisms remain largely unknown. Many sub-stances are difficult to remove by conventional water treatment processes. Thus, there is an intense research activity on all these topics.The objective of this chapter is to present a recent state of knowledge on emerging substances and their presence in the aquatic environment. After general considerations on emerging contaminants, the first part is focused on chromatographic methods coupled to mass spectrometry for their analysis and detection, and on detection of microplastics in water and sediment. The presence of alkylphenols, rare earth elements and nanoparticles in the aquatic environment is then discussed. Finally, examples of contamination described from around the world, from China to Portugal, Mexico, Colombia and Brazil, are presented