Geochemical barriers as a form of self-organization of geochemical systems (case of study Kerch Peninsula, Russia)

According to the author's concept, discharge of groundwater to the surface is considered as a sharp change of geochemical conditions, leading to the formation of geochemical barriers (GCB). In the article presented results of geochemical study of groundwater-soil-organic matter-gas interaction as example of Kerch Peninsula self-organizing system The geochemical barriers give rise to the formation of a kind of non-equilibrium geoecosystems with an individual structure of direct and inverse connections between the components, size and borders of geochemical systems (GCS) are determined by many factors: frequency and scale of discharge, chemical composition, temperature of the source and of the environment, phase transitions within the system with interacting heterogeneous media: "water – rocks", "water – atmosphere", "water – ice", "water – soil", "water – plants (including algae and other living organisms)", and etc. Polycyclic aromatic hydrocarbons (PAHs) are used as tracers of this interaction.

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Quantitative Assessment of Organic And Inorganic Contaminants In Charcoal Applied for Food Processing

10.21203/rs.3.rs-369239/v1 ◽

2021 ◽

Author(s):

Zbigniew Jelonek ◽

Monika Fabiańska ◽

Iwona Jelonek

Keyword(s):

Toxic Elements ◽

Prolonged Exposure ◽

Gas Chromatography Mass Spectrometry ◽

Moderate Degree ◽

Inorganic Contaminants ◽

Low Degree ◽

Wide Range ◽

Polycyclic Aromatic ◽

Living Organisms ◽

High Degree

Abstract Thirty-one batches of commercial charcoal from various regions of Poland and Germany were tested for the presence of twenty toxic elements and polycyclic aromatic hydrocarbons (PAHs) using gas chromatography - mass spectrometry (GC-MS). Elements that are toxic to living organisms were determined using atomic absorption spectroscopy (AAS). They were classified as elements representing a very high degree of hazard (As, Cd, Cu, Hg, and Pb), high degree of hazard (Zn, Ba, Cr, Mn, and Mo), moderate degree of hazard (Co, Ni, Sn, and Te), and a low degree of hazard for living organisms and the environment (Ag, Bi, Ce, Se, Sr, and Zr). When it comes to the most toxic elements, the highest concentration in the whole tested material was recorded for Cu. In addition, considerable amounts of Ba, Mn, and Sr, i.e., elements representing high or moderate degree of hazard, were found in the tested charcoals. Moreover, all charcoals contained a wide range of PAHs, from naphthalene to benzo(ghi)perylene, with concentrations in the range between 12.55 and 3554.11 ng/g of charcoal. In total, 25 unsubstituted PAHs were identified in the charcoal extracts. PAHs distributions were dominated by 5-ring PAHs. The results indicate the high carcinogenicity with ∑PAHcarc/∑PAHtot close to 1, as well as high TEQ and MEQ values. Thus, prolonged exposure to charcoal and charcoal dust might cause serious health problems. This applies to employees actively involved in the production and transport of charcoal, and, to a lesser extent, also to users of this fuel.

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Towards a nudging of stratospheric overshoots in the 3D mesoscale BRAMS model

10.5194/egusphere-egu21-1323 ◽

2021 ◽

Author(s):

Justine Pichon ◽

Emmanuel Riviere ◽

Abhinna Behera ◽

Jeremie Burgalat

Keyword(s):

Mesoscale Model ◽

Water Concentration ◽

Global Scale ◽

Satellite Measurement ◽

Model Categories ◽

Tropical Regions ◽

Water Ice ◽

Convective Clouds ◽

Starting Point ◽

Ice Water

Water repartition in the stratosphere is a key compound in the atmospheric chemical and radiative equilibrium. Since the 80&#8217;s, an increase of the water concentration in the stratosphere has been observed.This presence in the stratosphere can be explained by the slow ascent of air mass above convective clouds in tropical regions. The amount of water vapor entering in the stratosphere depends on the coldest temperature and countered during this slow ascent because it can lead to ice cristal formation that sediment and dehydrate the air masses. But some other processes may contribute to the stratospheric water budget, especially to explain the increase of water vapor. Stratospheric overshoots phenomenon can take part in the stratospheric hydratation, by injecting directly water ice in the stratosphere. Injected ice water, by sublimation, will hydrate stratosphere locally. The local role of overshoots is better known but their contributions at the global scale steal need to be quantified. In order to estimate this contribution, previous studies have used the 3D simulation mesoscale model BRAMS to show overshoot impact in the upper Tropical Tropopause Layer (TTL). These studies are the starting point of our study.The aim of this paper is to present the new development inside BRAMS to nudge stratospheric ice injection by overshoots. It uses an overshoot occurrence climatology from MHS (Microwave Humidity Sounder) satellite measurement. Ice injection in the model is made according to ice model categories previously shown to be present in the overshoot plumes with ratios already diagnosed in previous studies. Ice injection is made between two layers of TTL&#8217;s stratospheric part: between 380 and 385K and between 385 et 400K. Nudging is triggered only if, in the grid mesh (20 x 20 km) where MHS has detected an overshoot, BRAMS computes a cumulonimbus with a top above 13.5km. For the layer above 385 K isentrope, a subgrid box of 2 km x 2 km is considered for the computation of ice injection. Sensibility test of this nudging scheme will be presented in this presentation.&#160;

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THE ROLE OF GEOCHEMICAL BARRIERS IN THE DISTRIBUTION OF FLOWS OF POLYCYCLIC AROMATIC HYDROCARBONS IN THE MOUTH AREAS OF SEAS

18th SGEM International Multidisciplinary Scientific GeoConference SGEM2018, Science and Technologies in Geology, Exploration And Mining ◽

10.5593//sgem2018v/1.5/s02.063 ◽

2018 ◽

Author(s):

Aleksandr Khaustov

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Geochemical Barriers ◽

Polycyclic Aromatic

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Phytoremediation of PAHs in Contaminated Soils: A Review

Bioremediation Science and Technology Research ◽

10.54987/bstr.v9i2.609 ◽

2021 ◽

Vol 9 (2) ◽

pp. 1-6

Author(s):

Ibrahim Alkali Allamin ◽

Mohd Yunus Shukor

Keyword(s):

Contaminated Soils ◽

Environmental Concern ◽

Low Cost ◽

Large Area ◽

Carcinogenic Activity ◽

Secondary Pollution ◽

Polycyclic Aromatic ◽

Transport Loss ◽

Land Disposal ◽

Living Organisms

Polycyclic aromatic hydrocarbons (PAHs), which are also part of persistent organic pollutants (POPs), are considered to be especially toxic to humans (carcinogenic), likewise to plants, microorganisms and other living organisms. PAHs soil contamination occurs by storage leaking, transport loss, the land disposal of petroleum waste, and accidental or intentional spills. Due to their ubiquitous occurrence, recalcitrance, bioaccumulation potential and carcinogenic activity, PAHs are a significant environmental concern. The methods of controlling and repairing PAH-contaminated soils mainly include physical remediation, chemical remediation and phytoremediation. However, there was an increasing focus on phytoremediation technologies as a result of their unique advantages, including low cost, lack of secondary pollution and large-area application. Phytoremediation is therefore one of the soil remediation technologies with the greatest potential.

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Fractionation of polycyclic aromatic hydrocarbons at geochemical barriers

Vestnik of Saint Petersburg University Earth Sciences ◽

10.21638/spbu07.2021.108 ◽

2021 ◽

Vol 66 (1) ◽

Author(s):

Aleksandr P. Khaustov ◽

◽

Margarita M. Redina ◽

Keyword(s):

Mass Transfer ◽

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Environmental Protection Agency ◽

Stable State ◽

Geochemical Barriers ◽

The Us ◽

Polycyclic Aromatic ◽

Geochemical Markers ◽

Marker Compounds

The purpose of the study was to identify patterns of fractionation at geochemical barriers (GCB) of associations of marker compounds - polycyclic aromatic hydrocarbons (PAHs). Based on thermodynamic parameters, the throughput of GCB in geochemical systems (GCS) in relation to organic substances at the molecular level is analyzed. PAHs are very informative indicators of the properties of GCB (up to singular surfaces). The processes of migration and selective penetration through GCB of 15 PAHs from the list of priority pollutants recommended by the US Environmental Protection Agency (widely used in the world EPA list): Naphthalene (Naph), acenaphthene (Ace), Fluorene (Flourene), Phenanthrene (Phen), Anthracene (An), Fluoranthene (Flu), Pyrene (Py), Benzo(a)Anthracene (BaA), Chrysene (Chr), Benzo(b)Fluoranthene (BbFlu), Benzo(k)fluoranthhene (BkFlu), Benzo(a)pyrene (BaP), benzo(ghi)perylene (Bghi), Dibenzo(a, h) anthracene (DbA), Indeno(1,2-cd)pyrene (Ip). Being geochemical markers, these compounds can accumulate on barriers and selectively penetrate through them, making them especially important objects of study. Despite numerous studies, these mechanisms of mass transfer have not been sufficiently studied. The types of GCB have been identified in terms of their permeability to PAHs. It is shown that the functions of GCB in systems are much more significant and consist not only in the separation of systems from the external environment and the regulation of mass transfer. The above models of migration and accumulation are based on quantitative estimates, which makes the results more reasonable in comparison with the “conceptual” representations of the behavior of substances on GCB in most studies. The most important point - the influence of the medium contact time for establishing a stable state (stability by the migration of compounds) on GCB has been demonstrated.

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Assessment of Polycyclic Aromatic Hydrocarbons in Agricultural Soils of Teskelewu Community and Environs Impacted By Gas Flaring in Delta State, Nigeria

Journal of Applied Sciences and Environmental Management ◽

10.4314/jasem.v23i10.15 ◽

2019 ◽

Vol 23 (10) ◽

pp. 1861-1866

Author(s):

A.A. Enuneku ◽

B. Kubeyinje

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Agricultural Soils ◽

Environmental Pollutants ◽

Gas Chromatograph ◽

Ionization Detector ◽

Gas Flaring ◽

Flame Ionization ◽

Polycyclic Aromatic ◽

Living Organisms

Polycyclic aromatic hydrocarbons (PAHs) are emerging ubiquitous environmental pollutants with reported carcinogenic, mutagenic and teratogenic potentials on living organisms and humans. The objective of this study was to assess the concentrations of PAHs in agricultural soils of Tsekelewu Community and environs (Egbema Kingdom) in Warri North Local Government Area of Delta State, Nigeria impacted by gas flaring using gas chromatograph system Agilent 5890 Series 11 gas chromatograph equipped with Flame ionization detector (GC-FID). The results revealed that station 1 and 2 were fairly contaminated; with mean total PAH concentration of 236.40 μg/kg and 279.75 μg/kg respectively. Stations 3, 4, 6, 7 and 9 having mean total PAH concentration of 692.45μg/kg, 726.22 μg/kg, 739.82 μg/kg, 609.38 μg/kg, and 772.99 μg/kg were moderately contaminated. Heavy contamination was recorded in station 5 and station 8 with mean PAH concentrations of 1231.08μg/kg and 1224.33 μg/kg. The dominant PAHs in soil samples were benzo(a)anthracene, phananthrene and chrysene with benzo(a)anthracene having the highest concentration across all sample stations. The PAH concentration observed in this study is thus a serious cause for concern since soil contamination from gas flaring will likely continue. Measures that will attenuate PAHs concentrations in soil should be adopted as farmers are likely exposed by largely inhalation.Keywords: Hydrocarbons; Contamination; Agricultural soils; Gas flaring

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Impact flash evolution of CO 2 ice, water ice, and frozen Martian and lunar regolith simulant targets

Meteoritics and Planetary Science ◽

10.1111/maps.13581 ◽

2020 ◽

Vol 55 (10) ◽

pp. 2301-2319

Author(s):

Jon D. Tandy ◽

Mark C. Price ◽

Penny J. Wozniakiewicz ◽

Mike J. Cole ◽

Luke S. Alesbrook ◽

...

Keyword(s):

Lunar Regolith ◽

Water Ice ◽

Lunar Regolith Simulant ◽

Ice Water ◽

Impact Flash

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Imaging with Neutrons

Elements ◽

10.2138/gselements.17.3.189 ◽

2021 ◽

Vol 17 (3) ◽

pp. 189-194

Author(s):

Gilberto Artioli ◽

Daniel S. Hussey

Keyword(s):

Heterogeneous Media ◽

Imaging Techniques ◽

Dark Field ◽

Three Dimensions ◽

Dark Field Imaging ◽

Inorganic Composites ◽

Porous Matrices ◽

Living Organisms ◽

Cultural Heritage Objects ◽

Percolation Processes

By exploiting the penetration, attenuation, and scattering properties of neutrons, images of matter in two or three dimensions reveal information unobtainable using other probes. Despite the limitation in brilliance of neutron sources, several neutron-based imaging techniques are essential to different aspects of modern geoscience. Typical examples include the evaluation of porosity in rocks and sediments, mapping of light elements in solids, noninvasive probing of cultural heritage objects, investigations of thick engineering components, and the exploration of diffusion and percolation processes of fluids within porous matrices, organo-inorganic composites, and living organisms. Techniques under development include simultaneous neutron and X-ray tomography in heterogeneous media, Bragg-edge imaging, and the possibility of porosimetry from dark-field imaging.

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Phenanthrene Mitigates Cadmium Toxicity in Earthworms Eisenia fetida (Epigeic Specie) and Aporrectodea caliginosa (Endogeic Specie) in Soil

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15112384 ◽

2018 ◽

Vol 15 (11) ◽

pp. 2384 ◽

Cited By ~ 8

Author(s):

Ali Elyamine ◽

Javaria Afzal ◽

Muhammad Rana ◽

Muhammad Imran ◽

Miaomiao Cai ◽

...

Keyword(s):

Eisenia Fetida ◽

Cadmium Toxicity ◽

Interactive Effect ◽

Interactive Effects ◽

Toxicity Tests ◽

Aporrectodea Caliginosa ◽

Mixture Treatment ◽

Polycyclic Aromatic ◽

Single Compound ◽

Living Organisms

In classical toxicology studies, the interaction of combined doses of chemicals with dissimilar modes of toxic action in soil is complex and depending on the end point investigated and the experimental protocol employed. This study was used to examine the interactive effect of phenanthrene and Cadmium on two ecologically different species of earthworms; Eisenia. fetida and Aporrectodea. caliginosa. This interactive effect was scrutinized by using the acute toxicity test with the concentrations of 2.51 mg kg−1 and 3.74 mg kg−1, respectively, being lethal for 50% of E. fetida and A. caliginosa. The results showed that in the mixture treatment, phenanthrene at 5, 10, 15 and 20 mg kg−1 significantly mitigated both earthworms species mortality and body-mass loss. Moreover, the factor of Cd accumulated in E. fetida and A. caliginosa tissues was significantly decreased by about 12% and 16%, respectively. Linear regression correlation coefficient revealed that the reduction of both earthworm species mortality was negatively and significantly correlated (r2 = 0.98 ± 0.40 and 1 ± 3.9 p < 0.001) with phenanthrene concentration in soil. However, over 20 mg kg−1 of phenanthrene, both organisms mortality rate increased again, as was the Bioaccumulation factor of phenanthrene. Thus, this study proposes that the antagonistical effect of phenanthrene on Cd at a degree of concentration can be used to mitigate Cd effect on soil living organisms. However, as an implication of these results, the interpretation of standardized toxicity bioassays, including whole effluent toxicity tests and single-compound toxicity tests, should be performed with caution. In addition, risk assessment protocols for environment pollution by a mixture of metals and polycyclic aromatic hydrocarbons should include robust methods that can detect possible interactive effects between contaminants to optimize environmental protection.

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