Environmental Geochemical Studies Research Articles

The records of 239+240Pu and 137Cs of global fallout in Lake East Dongting Sediments and Responses to watershed environmental changes

Plutonium-239 + 240 and 137Cs in the environment can usually be used to track the impact of nuclear activities on the environment, and have become important tools in environmental geochemical studies. In this study, nine sediment cores (E1-E9) in Lake East Dongting were collected and measured for the activity concentration of 239+240Pu, 137Cs and the atomic ratio of 240Pu/239Pu, and then their vertical distribution characteristics were analyzed. The results show that: the activity concentrations of 137Cs and 239+240Pu in Lake East Dongting ranged from 5.26 ± 0.43 to 28.6 ± 2.23 Bq kg−1 and 0.29 ± 0.02 to 1.37 ± 0.09 Bq kg−1, with an average of 7.48 ± 0.68 Bq kg−1 and 0.39 ± 0.03 Bq kg−1, respectively. The atomic ratios of 240Pu/239Pu are 0.168 ± 0.012–0.211 ± 0.015, which are basically consistent with the global atmospheric deposition. The vertical profiles of 137Cs and 239+240Pu in sediment cores show obvious single-peak distribution in E1-E6 and bimodal distribution in E7-E9. The results of sedimentation rates calculated by 137Cs and 239+240Pu method ranged from 0.59 cm y−1 to 1.99 cm y−1 with a mean of 1.18 cm y−1 and 0.61 cm y−1 to 2.18 cm y−1 with a mean of 1.26 cm y−1. The inventories of 137Cs and 239+240Pu in nine sediment cores are 5.87–10.8 kBq m−2 and 307–545 Bq m−2, which are about 8–14 and 9–15 times the inventory in the global average atmospheric deposition at the same latitude respectively. Comparing the results of the sedimentation rates and the inventories from different sampling points indicates that extreme climatic events and human activities have a significant impact on sediment environment of Lake East Dongting.

Simultaneous Determination of Fluorine and Chlorine in Marine and Stream Sediment by Ion Chromatography Combined with Alkaline Digestion in a Bomb

Fluorine and chlorine are important tracers for geochemical and environmental studies. In this study, a rapid alkaline digestion (NaOH) method for the simultaneous determination of fluorine and chlorine in marine and stream sediment reference samples using ion chromatography is developed. The proposed method suppresses the volatilization loss of fluorine and chlorine and decreases the matrix effects. The results are in good agreement with fluorine ~100%, chlorine ranging from 90 to 95% of the expected concentrations. The detection limits of this method were 0.05 μg/g for fluorine and 0.10 μg/g for chlorine. This method is simple, economical, precise and accurate, which shows great potential for the rapid simultaneous determination of fluorine and chlorine in large batches of geological and environmental samples commonly analyzed for environmental geochemistry studies.

Environmental Geochemistry Studies To Assess The Ecological Risks Of Gold Mining Activities In Egypt

Environmental Geochemistry Studies To Assess The Ecological Risks Of Gold Mining Activities In Egypt

Investigation of the relationship between rare earth elements, trace elements, and major oxides in soil geochemistry.

Investigation on the behavior of elements in the soil is important both in exploration and environmental geochemistry studies. Rare earth elements (REEs) are the most useful among all trace elements. REE studies have shown that they have important applications in igneous, sedimentary, and metamorphic petrology. This work aims to investigate the relationship of these elements with one another and the behavior of the major oxides and trace elements with REEs. Soil samples were obtained from the alteration site possibly related to mineralization and were analyzed for major oxides, trace elements, and REEs. The relationships between the major oxide-trace element/heavy metal and REE were investigated by statistical methods, such as descriptive statistics, correlation coefficient, and principle component analysis. According to the correlation coefficient matrix, light REEs (LREEs) showed weak to moderate negative correlation with MgO and MnO and moderately positive correlation with SiO2 and K2O. No association was detected between the heavy REEs (HREEs) and the main oxides, but a strong positive correlation with LREEs was observed. For the trace elements, LREE showed a weak positive correlation with Ba and Sn and moderate to strong positive correlation with As, Hf, Nb, Rb, Ta, Th, U, W, and Zr. They also displayed weak to moderate correlation with Sc, Co, Zn, Ni, and V. HREE showed weak to moderate positive correlation with Ni, Cs, Ga, Hf, Th, Zr, As, and LREE. Although REEs exhibited no direct correlation with Au and Ag, they showed a good correlation with some trace elements that are related to hydrothermally altered products. This study showed that REEs can also be used in exploration and environmental geochemistry studies by exploiting the relationship between REEs and other trace/heavy metal elements.

Feasibility of using “Off-The-Shelf” clinical linac for soil multi-elemental instrumental photon activation analysis

“Off-the-shelf” clinical linear electron accelerators (LINAC) have been suggested as alternative to research accelerators once they are no longer suitable for the medical applications. We investigated feasibility of utilising a modified LINAC for instrumental photon activation analysis (IPAA) as a tool in environmental geochemistry studies. The IPAA results were compared with those obtained using a MT-25 research accelerator at Joint Institute for Nuclear Research in Dubna, Russia. To investigate soil pollution in Antalya, Turkey, 90 surface soil samples were analysed and significant enrichments of Ni, Cr and As were found.

Sampling Density in Regional Exploration and Environmental Geochemical Studies: A Review

A variety of factors contribute to the proper and efficient evaluation of geochemical programs including sampling medium, sample size and sample fraction, sampling density, digestion procedure, and analytical techniques. Among the aforementioned factors, sampling density is of great importance, affecting project ability to detect anomalous sites, which are either economically viable or environmentally hazardous. It is quite critical to have a sufficient number of samples to delineate geochemical anomalies or baselines and to reveal the relative variations in elemental concentrations in a study area. The resolution of the subsequent maps obtained by sampling greatly depends on sampling density. While a large number of samples may generate redundant data, a small number of samples smooth out the patterns and may completely miss anomalies. This review provides a platform for applied geochemists who desire to design a sampling scheme for a regional geochemical program and do not have the financial resources to perform an orientation survey, which will give them the necessary information for designing, according to project objectives, a cost-effective regional geochemical survey for their study area. It is advisable to integrate during the desktop study all available information, such as geological, structural, geophysical, remote sensing data and topographical data by using different data fusion algorithms to arrive at a sampling density fit-for-purpose of the target area. This in turn facilitates an effective spatial positioning of sample locations. Quantitative analyses of the efficiency of different sampling densities for delineating geochemical patterns have not been well documented, warranting more attention and research.

Geogenic versus anthropogenic behaviour and geochemical footprint of Al, Na, K and P in the Campania region (Southern Italy) soils through compositional data analysis and enrichment factor

Geochemical studies that focus on environmental applications tend to approach the chemical elements as individual entities and may therefore offer only partial and sometimes biased interpretations of their distributions and behaviour. A potential alternative approach is to consider a compositional data analysis, where every element is part of a whole. In this study, an integrated methodology, which included compositional data analysis, multifractal data transformations and interpolation, as well as enrichment factor analysis, was applied to a geochemical dataset for the Campania region, in the south of Italy, focusing in particular on the behaviour, footprints and sources of a smaller pool of elements: Al, Na, K and P. The initial dataset included 3669 topsoil samples, collected at an average sampling density of 1 site per 2.3 km2, and analyzed (after an aqua regia extraction) by a combination of ICP-AES and ICP-MS for 53 elements. Frequency based methods (Clr biplot, Enrichment Factor computation) and frequency spatial-method (fractal and multifractal plots) allowed identifying the relationships between the elements and their possible source patterns in Campania soils in relation to a natural occurring concentrations in geogenic material (rocks, soils and sediments) or human input. Results showed how the interpretation of concentration and behaviour of Al, Na, K and P was enhanced thanks to the application of data log-ratio transformation in univariate and multivariate analysis compared to the use of raw or log-normal data. Multivariate analyses with compositional biplot allowed the identification of four element associations and their potential association with the underling geology and/or human activities. When focusing on the smaller pool of elements (Al, P, K and Na), these relationships with the unique geology of the region, were largely confirmed by multifractal interpolated maps. However, when the local background was used for the calculation of the enrichment factor, the resulting interpolated maps allowed to identify smaller areas where the greater concentrations of P could not be possibly associated to a mineralisation (e.g., ultrapotassic rocks) but were more likely to be associated to anthropogenic input such as agriculture activities with potentially extensive use of phosphate fertilizers. The integrated approach of this study allowed a more robust qualitative and quantitative evaluation of elemental concentration, providing in particular new and vital information on the distribution and patterns of P in soils of the Campania region, but also a viable, more robust, methodological approach to regional environmental geochemistry studies.

The Importance of Analytical Chemistry in Environmental Geochemistry Studies in Mexico

<p>This review presents environmental geochemistry studies developed in Mexico involving analytical chemistry applied to marine, lake, lagoon, dam, and fluvial sediments, soils, and groundwater over the past 15 years. The paper summarizes the objectives of the research, the analytical methods that were used, the methodologies applied for the interpretation of the results, and the primary findings for the areas and specific substrates that were studied. Although diverse analytical techniques were applied, atomic absorption spectrometry was the primary method of analysis, followed by inductively coupled plasma atomic emission spectroscopy. Studies are widespread in the Mexican territory although some areas are still lacking in information; in addition, most of the country’s contamination problems have yet to be remediated.</p>

A Rapid Acid Digestion Technique for the Simultaneous Determination of Bromine and Iodine in Fifty‐Three Chinese Soils and Sediments by ICP‐MS

Bromine and iodine are important tracers for geochemical and environmental studies. In this study, a rapid acid digestion (HNO3 + HF) with ammonia dilution for the simultaneous determination of bromine and iodine in soils and sediments using ICP‐MS was developed. The recoveries of Br and I were controlled by the synergic effect of temperature and time. It took only 15 min at 140 °C for the complete recovery of Br and I in sediment (GSD‐2) and soil (GSS‐24) reference materials, which is a process that needs 2–6 h at 90 °C. A serious loss of Br and I was found at a higher digestion temperature of 190 °C. A 5% v/v NH4OH dilution effectively eliminated the memory effects and stabilised the signals of Br and I. Moreover, ammonia dilution also avoided the corrosiveness of HF on the sample introduction system and torch of ICP‐MS. Tellurium is a more suitable internal standard element than In in the ammonia medium. To avoid the adsorption of residues of dissolution on Te, addition of Te should be carried out after centrifuging the solution. The developed method was successfully applied to determine Br and I in fifty‐three Chinese soil and sediment reference materials. This simple method shows great potential for the rapid determination of Br and I in large batches of geological and environmental samples commonly analysed for mineral exploration and environmental geochemistry studies.

On-line in situ determination of deuterium content in water via FTIR spectroscopy.

Hydrogen stable isotope ratios are critical indicators in environmental geochemical studies for characterizing runoff, determination of groundwater groups and water uptake by plants etc. (generally used in combination with 18O analysis). While the common technique for this hydrogen isotope measurement is Mass Spectrometry, FTIR (Fourier transform infra-red) spectroscopy may be an alternative method, with the advantage of direct and simple operating measurements. The FTIR spectrometer has the advantage of performing in situ measurements, which can delineate continuous geochemical processes. In situ measurements decrease errors that may be a consequence of sample delivery to the laboratory and off-site analysis procedures. In this study, we have developed a new simple procedure for in situ hydrogen stable isotope ratio measurements. We discovered that the HDO (hydrogen, deuterium, and oxygen) absorbance peak at 2504 cm−1 is the most suitable for water sample direct analysis, with the FTIR device, using a circular sample cell for liquid samples. A case study analyzing water samples from a karstic cave (Sif cave, Israel) verified the following: (a) on-line determination of water D/H ratio can be carried out with the portable FTIR spectrometer (and thus can be used for field measurements such as in the Sif cave) and (b) the D concentration sensitivity achieved was at a 0.01‰ level, with a standard deviation of 0.006‰.

MEDICAL GEOCHEMISTRY A KEY IN THE PRECAUTIONARY MEASURES AGAINST THE DEVELOPMENT OF CANCER AND OTHER DISEASES

A considerable number of diseases are directly related to environmental impact. Toxic metals such as Hg, Pb, Cd, and As may damage significantly the human health when they exceed certain levels in the body. For example specific precautions should be taken for the diet of pregnant women and the children. Lead concentrations exceeding the safe values can cause severe damage to the development of central nervous system, as well as a general developmental delay of fetuses and young children, interfering with the functioning of almost every brain neurotransmitter. In particular for the pregnant women, it has been found that the exposure of the fetus on high lead values may cause, apart from neurological and behavioral problems, low birth weight, pre-term delivery, spontaneous abortion and stillbirth. Organic mercury (methyl mercury) is the most dangerous form of mercury, because it is the most easily absorbed orally and crosses into the brain and fetus so readily. Populations exposed to chemical compounds containing As, Ni, Cr, Cd, etc. are considered of high-risk in developing cancer. Environmental geochemical studies can help in assessing the quality of the environment as well as the determination of the sources of pollutants, their behaviour and other characteristics. This knowledge is necessary in any application of remediation methodologies and waste management for the prevention of pollutants in getting into the food chain. It is also used in determining safe criteria regarding the quality of soils, drinking water, construction of schools, playgrounds etc. In this work the importance of environmental geochemical research and its applications towards the protection of human health is demonstrated.

Biogeochemical Surveys Using Poultry Components from Mangampeta Barite Area, Andhra Pradesh, India

The present work deals with the trace element interactions in excreta, feathers, and eggs of hens of backyard poultry of Mangampeta barite area, Kadapa District, Andhra Pradesh to determine its significance in biogeochemical surveys. For purpose of comparison, excreta, feathers and eggs from the birds of caged system of poultry in Tirupati, Andhra Pradesh are also collected. The excreta and eggs of hens of backyard poultry reflect the composition of their immediate geochemical environment while those of hens of caged system of poultry show their feed composition. Variations in trace element content are observed in poultry components on ash weight and dry weight basis. Organic matter plays an important role in the behavior and distribution of trace elements. The excreta of hens of backyard poultry can be utilized as a tool in biogeochemical orientation surveys as they reflect their surrounding geochemical environment. The biogeochemical investigations of all these biological samples are helpful in the preparation of multi-element atlases for the effective study of environmental geochemistry.

Element enrichment factor calculation using grain-size distribution and functional data regression

In environmental geochemistry studies it is common practice to normalize element concentrations in order to remove the effect of grain size. Linear regression with respect to a particular grain size or conservative element is a widely used method of normalization. In this paper, the utility of functional linear regression, in which the grain-size curve is the independent variable and the concentration of pollutant the dependent variable, is analyzed and applied to detrital sediment. After implementing functional linear regression and classical linear regression models to normalize and calculate enrichment factors, we concluded that the former regression technique has some advantages over the latter. First, functional linear regression directly considers the grain-size distribution of the samples as the explanatory variable. Second, as the regression coefficients are not constant values but functions depending on the grain size, it is easier to comprehend the relationship between grain size and pollutant concentration. Third, regularization can be introduced into the model in order to establish equilibrium between reliability of the data and smoothness of the solutions.

Heavy Metals in the Water, Plants, and Bottom Sediments of the Volga River Mouth Area

ABSTRACT Lychagin, M.Yu.; Tkachenko, A.N.; Kasimov, N.S., and Kroonenberg, S.B., 2015. Heavy metals in the water, plants, and bottom sediments of the Volga River mouth area. Deltaic landscapes occupy a special place in environmental geochemical studies of water bodies. Their ecotone position at the land–sea boundary determines the biological richness of the deltaic ecosystems and creates a unique variety of landscape–geochemical conditions. The Volga River delta is one of the largest in the world. It serves as a geochemical “focus” that reflects the character of fluxes of substances of natural and anthropogenic origin in the entire system of the Volga basin. This paper presents the results of long-term environmental geochemical research of aquatic landscapes in the mouth area of the Volga River. The study has shown the high spatial and temporal variability of the chemical element migration in the area due to the influence of hydrodynamic conditions, variations in water and sediment discharge, and local fe...

Medical geochemical investigations in taking precautionary measures against diseases. Protection and human health

A considerable number of diseases are directly related to environmental impact. Toxic metals such as Hg, Pb, Cd, and As may damage significantly the human health when they exceed certain levels in the body. For example specific precautions should be taken for the diet of pregnant women and the children. Lead concentrations exceeding the safe values can cause severe damage to the development of central nervous system, as well as a general developmental delay of fetuses and young children, interfering with the functioning of almost every brain neurotransmitter. In particular for the pregnant women, it has been found that the exposure of the fetus on high lead values may cause, apart from neurological and behavioral problems, low birth weight, pre-term delivery, spontaneous abortion and stillbirth. Organic mercury (methyl mercury) is the most dangerous form of mercury, because it is the most easily absorbed orally and crosses into the brain and fetus so readily. Populations exposed to chemical compounds containing As, Ni, Cr, Cd, etc. are considered of high-risk in developing cancer. Environmental geochemical studies can help in assessing the quality of the environment as well as the determination of the sources of pollutants, their behaviour and other characteristics. This knowledge is necessary in any application of remediation methodologies and waste management for the prevention of pollutants in getting into the food chain. It is also used in determining safe criteria regarding the quality of soils, drinking water, construction of schools, playgrounds etc. In this work the importance of environmental geochemical research and its applications towards the protection of human health is demonstrated.

The pollution of groundwater and unsaturated zone rocks by oil products and PAH in urban areas

An approach to assessing the hazard of unsaturated zone rocks as a source of subsoil-water secondary pollution by oil products and PAH is considered based on environmental-geochemical studies of soils and rocks of the unsaturated zone, groundwater, and snow, which were carried out during the rehabilitation of the water environment of Lefortovskii Park (Moscow). The impact of the primary pollution sources is analyzed, and the formation of groundwater and rock pollution by oil products and PAH is considered. To assess the role of the unsaturated zone as a secondary source of pollution of surface and subsurface waters under the conditions of possible elimination of the primary sources, the transport of oil products (benzol and toluene) and PAH (pyrene) in unsaturated zone was simulated using WHI UnSat Suite Plus software package.

Heavy metal contamination in sediments of Balanagar industrial area, Hyderabad, Andra Pradesh, India

Environmental geochemical studies were carried out to find out the extent of contamination in sediments due to heavy metals in Balanagar industrial area, Hyderabad, Andhra Pradesh, India. The industrial area consisting of 350 small and large industries manufacturing battery, steel planting, pharmaceutical chemicals, metal plating, etc. The present study was undertaken on sediment contamination in Balanagar industrial area, to determine extent and distribution of heavy metals (Cu, Cr, Ni, Pb, Zn, As) and to delineate the source. There is no treatment plant in the industrial area, and many industries release the effluents into nearby nalas and lakes. Solid waste from the industries is also being dumped along the roads and near the open grounds due to which heavy metals migrate from solid waste to the groundwater. The sediments samples were collected from the study area in clean polythene covers and were analyzed for their heavy metals by X-ray fluorescence spectrometry. The concentration ranges of different heavy metals were Cr, 96.2–439.6 mg/kg; Cu, 95.7–810 mg/kg; Ni, 32.3–13,068.2 mg/kg; Pb, 59.2–512 mg/kg; Zn, 157.1–4,630.5 mg/kg; Co, 1.8–48.3 mg/kg; and V, 35.2–308.5 mg/kg. High concentration of heavy metals in sediments can be attributed to some pharmaceutical and metal industries in the study area. Based on the results obtained, suitable remedial measures can be adopted such as phytoremediation and bio-remediation for reduction of heavy metals in sediments.

Environmental geochemistry studies in the area of Idrija mercury mine, Slovenia

Five centuries of mining and processing of mercury ore in the Idrija area have resulted in widespread contamination of different environmental compartments. Environmental impacts on a regional and local scale, caused by atmospheric emissions from the Idrija ore roasting plant, were established in the investigations of mercury spatial distribution in soil and attic dust in 160 km(2) area. Very high values were determined in the Idrijca River valley, and they decrease exponentially with the distance from Idrija. Mercury concentrations in attic dust are higher than in surrounding soils and the attic dust/soil ratio changes with distance. Measurements of mercury in the air confirmed widespread dispersion of mercury and showed highly elevated mercury concentrations around roasting plant and mine ventilation shaft. Beside, systematic monitoring of mercury contents in the stream sediments has demonstrated that huge amounts of mercury are stored in areas where ancient overbank sediments were deposited, and there was no decrease in mercury concentration in active sediments during the last 15 years. Recently, interesting and extremely polluted locations of historical small-scale roasting sites in the Idrija surroundings were discovered. Ongoing geochemical study aims to determine the extreme pollution and significance of these sites for wider contamination of soils and aquatic systems. Presented studies have shown that Hg mining in Idrija caused intense pollution of local and regional environment including the aquatic systems in the Gulf of Trieste, which is seen as the final sink of a major part of the Hg stored in soils and river sediments in the Idrija area.

Determination of geochemical background for environmental studies of soils via the use of HNO3 extraction and Q–Q plots

The procedure proposed in this study is based on the extraction of elements in soils by analytical grade HNO3, the distribution of the elemental data displayed on probability graphs (Q–Q plots) and the visualization of the results spatially by GIS software. The applicability of the procedure is demonstrated in an urban area and its surroundings (Kavala, northern Greece). A major (Ca) and a trace (Ag) element are used as examples in order to demonstrate the applicability of the proposed procedure. Normal probability and lognormal probability plots of Ca and Ag show that their concentrations are lognormally distributed and that their geochemical baseline and anomaly threshold values can be calculated with the aid of their geometric mean and geometric deviation. The advantages of the proposed procedure are simplicity, comprehensiveness, and low cost. It can be applied to environmental geochemical studies of soils in a variety of areas.

Assessment of heavy metal contamination in soils at Jajmau (Kanpur) and Unnao industrial areas of the Ganga Plain, Uttar Pradesh, India

Environmental geochemical studies were carried out in and around Jajmau (Kanpur) and Unnao industrial areas (80°15′–80°34′E longitude and 26°24′–26°35′N latitude), of Uttar Pradesh to find out the extent of chemical pollution in soil due to industrial waste. Jajmau and Unnao are prominent centers for leather processing clusters of tannery industries (about 450) along the banks of river Ganga, besides other industries. Geologically the study area is beset with alluvium of Quaternary age consisting of older alluvium of middle to upper Pleistocene and newer alluvium of Holocene. The climate of the study area is semi-arid type. Fifty-three soil samples were collected from Jajmau and Unnao industrial areas from top 15 cm layer of the soil and were analyzed for heavy metals by using Philips MagiX PRO-PW 2440 X-ray fluorescence spectrometer. The data reveals that the soil in the area is significantly contaminated with heavy metals such as chromium varies from 161.8 to 6227.8 mg/kg (average of 2652.3 mg/kg), Ba varies from 44.1 to 780.9 mg/kg (average of 295.7 mg/kg), Cu varies from 1.7 to 126.1 mg/kg (average of 42.9 mg/kg), Pb varies from 10.1 to 67.8 mg/kg (average of 38.3 mg/kg), Sr varies from 46.6 to 150.6 mg/kg (average of 105.3 mg/kg), V varies from 1.3 to 208.6 mg/kg (average of 54.4 mg/kg) and Zn varies from 43.5 to 687.6 mg/kg (average of 159.9 mg/kg). Soil contamination was assessed on the basis of geoaccumulation index, enrichment factor (EF), contamination factor and degree of contamination. Indiscriminate dumping of hazardous waste in the study area could be the main cause of the soil contamination, spreading by rainwater and wind. Distribution and correlation of heavy metals in soil along with possible remedial measures are discussed.