Search

Purpose: To determine and compare the frequency of contamination on different sites of healing abutments (HAs) a=er steriliza3on with Phloxine B dye on unused and used HAs a=er steriliza3on. Materials and Methods: A total of 60 HAs were divided into two test groups: (1) used and sterilized and (2) a control group (unused). The test group was evaluated for contamina3on a=er steriliza3on; the control group did not undergo any procedure. Data were analyzed using SPSS version 22 (IBM). Descrip3ve sta3s3cs were used to determine the frequency of contamina3on in the different groups and at the different HA sites. Chi-square test was used to evaluate the association of frequency of contamination with the HA site and design. The level of significance was kept at P ≤ .01. Results: The test group showed more contamination compared to the control group. The most contaminated sites were the screw thread and the screwdriver engagement location. Conclusions: HA reuse is cost-effective, but cleaning and sterilization was not effective for these components; thus, HAs need to be reused with caution because they were heavily contaminated when compared to new HAs. Among the different sites, the screw thread and screwdriver engagement sites were more prone to contamination. HA type did not influence the frequency of contamination. [ABSTRACT FROM AUTHOR]

The precise range of contamination determines the cost of treating heavy metals contamination of soils at industrial sites and was a key aspect of soil heavy metals contamination management. The pollution level and spatial correlation of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in one hundred and thirty topsoil samples from a typical contaminated site was analysed. Geochemical analysis showed that Hg pollution was the most serious in the site, followed by Cd, Pb, Zn, Cu and Cr. The contents of As and Ni in the soil did not exceed the background values. The interpolation accuracy, interpolation results and spatial distribution of inverse distance weight method (IDW), local polynomial method (LPI), radial basis function method (RBF) and ordinary kriging method (OK) were compared, respectively. The results show that the range, mean and coefficient of variation of the four interpolation methods were generally lower than that of the sampled data, which was mainly caused by smoothing effect. The smoothing effect of LPI and OK were the most serious, while the smoothing effect of IDW and RBF were not obvious. The optimal interpolation method of Cd, Cr, Hg, Pb and Zn in polluted sites was RBF and the optimal interpolation method for As, Cu and Ni was IDW. The evaluation of polluted area by IDW and RBF interpolation method was ranked as IDW > RBF, which was much larger than that calculated by sampling point. Both interpolation methods could increased the area of polluted area. The probability kriging (PK) method was similar to that based on sampling points, which can greatly improve the calculation accuracy of heavy metals polluted area in industrial contaminated sites. Geochemical data and spatial interpolation results show that phytoremediation techniques was the most suitable for remediation of heavy metal contaminated soils at this site. [ABSTRACT FROM AUTHOR]

Low remediation efficiency due to low bioavailability is a primary restrictive factor for phytoremediation applications. Specifically, this investigation examines whether Suaeda heteroptera Kitagawa (S. heteroptera) can be used in combination with β-cyclodextrin (β-CD) to remediate contaminated site. The study was conducted on the growth response of S. heteroptera, bioavailability and dissipation of petroleum hydrocarbons (PHs) in soil under the influence of β-CD Our preliminary studies confirmed that β-CD is effective in increasing the biomass and height of plants. The presence of β-CD could dramatically elevate polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in S. heteroptera. Moreover, a remarkable positive correlation between PHs levels in roots with the dosage of β-CD and a negative correlation between the PHs levels in roots with KOW of PHs have been observed. The dissipation of n-alkanes was estimated to be 38.73–62.27%, and the dissipation of PAHs was 36.59–60.10%. In addition, the dissipation behavior of n-alkanes and PAHs was well agreement with the first-order kinetic model. These results display that applying β-CD accelerated the desorption process of PHs from soil and promoted the absorption process of PHs onto the root epidermis. The enhancement of phytoremediation was achieved by increasing the bioavailability of PHs. NOVELTY STATEMENT: There has been an increasing concern regarding soil contamination by petroleum hydrocarbons (PHs) released by industrial activities. The study attempted to investigate how β-CD affects the phytoremediation of PHs-contaminated sites. The findings of this study offer an environmentally friendly and cost-effective method of phytoremediating industrially contaminated sites using β-CD enhanced-phytoremediation. [ABSTRACT FROM AUTHOR]

Pollution makes some leisure activities not only possible but pleasurable, an analysis known as "polluted leisure." In this paper, I extend this analysis with case examples of leisure participants adept use of polluted spaces. This adept use suggests that some leisure participants are "enskiled" at polluted leisure, possessing an embodied ecological familiarity with polluted spaces similar to a sailor who has a real knack for getting their sea legs. I present a case example of skateboarders building formal and informal skateparks on remediated Superfund sites and brownfields to further encourage this notion of polluted leisure enskilment. I then develop this notion of polluted leisure enskilment using Guattari's "ecosophy," a way of being most suitable for our Anthropocene age, claiming that skateboarding's esthetic enmeshed in polluted space offers a lived ecosophy. I conclude with potential extensions of this research in leisure studies, spatial justice, and skate studies. [ABSTRACT FROM AUTHOR]

Microbial remediation of organically combined contaminated sites is currently facing technical challenges. White rot fungi possess broad-spectrum degradation capabilities, but most of the studies are conducted on polluted water bodies, and few research focus on the degradation of combined organically contaminated soils. This study aimed to investigate the physiological changes in Trametes versicolor to enhance its simultaneous degradation ability towards benzo(a)pyrene (BaP) and TPH. The results demonstrated that Trametes versicolor, when subjected to liquid fermentation, achieved an 88.08% degradation of individual BaP within 7 days. However, under the combined contamination conditions of BaP and TPH, the BaP degradation rate decreased to 69.25%, while the TPH degradation rate was only 16.95%. Furthermore, the degradation rate of BaP exhibited a significant correlation with the extracellular protein concentration and laccase activities. Conversely, the TPH degradation rate exhibited a significant and positive correlation with the intracellular protein concentration. Solid-state fermentation utilizing fungal agents proved to be the most effective method for removing BaP and TPH, yielding degradation rates of 56.16% and 15.73% respectively within 60 days. Overall, Trametes versicolor demonstrated a commendable capability for degrading combined PAHs-TPH pollutants, thereby providing theoretical insights and technical support for the remediation of organically combined contaminated sites. [ABSTRACT FROM AUTHOR]

Identification of preferential flow‐paths, such as fractures, is required for various issues in geosciences. When chemicals are injected into the subsurface, monitoring the resulting structural and chemical changes remains a challenge. The ability of geophysical tomography to tackle this problem is not fully explored due to the lack of numerical methods suitable for modeling narrow structures. We explore how discrete representation of preferential flow‐paths provides innovative ways to invert electrical resistivity data collected during reagent injection at a contaminated site. The data set is inverted with a scheme where a new fracture is added at every iteration. This allows identifying newly created narrow conductive structures from the field data collected before and after injection. Fracture location remains overall consistent despite using different starting points for the fracture search. A prior constraint on fracture length improves convergence. These results show the potential of discrete inversion for identifying narrow structures from electrical resistivity monitoring. Plain Language Summary: In some geoscience activities, such as water extraction, geological storage, and contaminant fate, chemical solutions are injected into wells, which potentially leads to modify the system properties. Identifying preferential flow‐paths is therefore necessary even though monitoring structural and chemical changes in the subsurface remains a challenge. Electrical geophysical imaging techniques may be adapted to provide information for this purpose. However, their potential is not fully explored due to the limitations of numerical models to represent small‐scale structures. In this work, we explore the representation of preferential flow‐paths by discrete elements for the inversion of electrical resistivity data collected during a reagent injection at a contaminated site. The inversion scheme based on discrete forward simulations successively identifies small‐scale structures and focuses on evaluating their localization and length. The results show the need for further efforts to use discrete electrical resistivity inversion in the presence of narrow structures. Key Points: Standard modeling strategies are not well suited to identify narrow geological structures from cross‐borehole electrical data inversionInversion scheme based on discrete‐dual‐porosity forward simulations enable to image narrow preferential flow‐paths from electrical dataPrior assumptions are needed to invert the position and length of narrow preferential flow‐paths [ABSTRACT FROM AUTHOR]

A quantitative understanding of the migration of munitions and canonical objects in the nearshore is needed for the effective management of contaminated sites. Migrations of munitions with a density range of 2000 kg/m3 to 5720 kg/m3 were quantified in a large-scale wave flume. The forcing consisted of six cases of varying wave heights, periods, still water depths, and durations. The cross-shore profile, typical of natural sandy beaches, was sub-divided into swash, surf, and offshore zones. Overall, 2228 migration measurements were recorded with 16% and 84% of the migration observations classified as "motion" (net distance > 0.5 m) and "no motion" (net distance ≤ 0.5 m), respectively. The probability of munitions migration increased with proximity to the shoreline. There was a nearly equal probability of onshore or offshore migration in the swash zone. Migration in the surf zone tended to be offshore-directed (65%), while migration was onshore-dominant (65%) in the offshore zone. Migration in the offshore zone was preferentially onshore due to skewed waves over flat bathymetry. Less dense munitions in the offshore zone may have migrated offshore likely still related to the skewed nature of the wave profile causing transport in both directions through the majority of the wave phase. The largest migration distances occurred in the surf zone likely due to downslope gravity. Migration in the surf and swash zones is a balance between skewed/asymmetric forcing and downslope gravity, with downslope gravity tending to be pronounced provided the forcing is sufficient to initiate motion. An exception was sometimes observed in the swash zone where onshore forcing was sufficient to transport munitions to the seaward side of the berm where they became trapped in a bathymetric depression between the dune and berm. Relating overall migration (Lagrangian) to fixed hydrodynamic measurements (Eulerian) was ineffective. Parameters such as the Shields number, wave skewness, and wave asymmetry estimated from the closest measurement location were insufficient to predict migration. Large scatter in the migration data resulting from competing hydrodynamic, morphodynamic, and munitions response processes makes robust deterministic predictions with flow statistics and dimensionless numbers difficult. [ABSTRACT FROM AUTHOR]

The Little St. Francis River and its tributaries drain metals-contaminated areas of the Madison County Mines National Priority List Superfund site (MCM) which was designated in 2003 to facilitate remediation of metals contamination within the MCM. One concern for natural resource trustees in the MCM is the potential effects of elevated metals concentrations on the federally threatened St. Francis River crayfish, Faxonius quadruncus, which has a geographic range that is limited to the St. Francis River watershed. A survey of riffle-dwelling crayfish, in-situ cage study, and laboratory toxicity tests were conducted to assess the effects of mining-derived metals on F. quadruncus and other crayfish species in the MCM. Crayfish densities were significantly greater at sites upstream of metals releases from historical mining (henceforth mining releases) compared to densities at sites downstream of mining releases, and metals concentrations in whole-body crayfish, surface water, sediments, macroinvertebrates, fish, and plant material were greater at sites downstream of mining releases compared to sites upstream of mining releases. Crayfish densities were also negatively correlated with consensus-based adverse effects indices, expressed as surface-water toxic units and sediment probable effects quotients. Decreased growth and increased mortality during cage and laboratory studies were likely due to exposure to, and subsequently uptake of, elevated concentrations of metals. Crayfish in all studies were found to bioaccumulate metals, which supports their utility as bioindicators of metals contamination. Study results show that elevated metals concentrations associated with mining releases in the MCM continue to adversely affect biota, including the federally threatened F. quadruncus. [ABSTRACT FROM AUTHOR]

Accidental fuel spills associated with the storage, transfer, and use of diesel fuel for power generation have occurred on sub‐Antarctic Macquarie Island since the establishment of the island's research station in 1948. An extensive in situ remediation program was implemented by the Australian government from 2009 to 2016 that used nutrient addition and air sparging to enhance the microbial degradation of petroleum products. During this period, a range of ecotoxicological assessments were conducted to better understand the impacts of fuel in soils on native biota and their sensitivity. This study compiles this ecotoxicological data into a species sensitivity distribution (SSD) to establish environmental quality guideline values (EQGVs) for fuels in soils on Macquarie Island. The SSD model includes 13 critical effect concentrations (CECs) selected using an expert judgment approach. These include data from functional and community‐based tests as well as traditional single‐species toxicity tests using microbes, plants, and invertebrates and representing the range of carbon content (~3%–48%) and fuel composition at various stages of degradation (from fresh to 18 months aged) in soils as occurs at contaminated sites on the island. A protective concentration (PC80) of 97 mg/kg TPH C9–C40 (95% CI 24–283) was derived for special Antarctic blend diesel from the SSD and is recommended as an appropriate site‐specific EQGV and potential remediation target for the immediate station area in the vicinity of infrastructure. More conservative PC values are also provided for areas with higher conservation values outside the station footprint. These EQGVs are the first to be produced for fuels in the sub‐Antarctic and Antarctic regions. They will be used to inform ongoing environmental management on Macquarie Island and are likely suitable and recommended for use more broadly across the sub‐Antarctic. Integr Environ Assess Manag 2024;20:2334–2346. © 2024 Commonwealth of Australia. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: This study has produced the first environmental quality guideline value (EQGV) for fuel for the sub‐Antarctic and Antarctic region; a site‐specific PC80 of 97 (24–283) mg/kg total petroleum hydrocarbons for diesel fuels in soils.We use adapted criteria and an expert judgment approach to select 13 toxicity estimates from functional, community, and traditional single‐species toxicity tests using microbes, plants, and invertebrates from Macquarie Island for inclusion in a species sensitivity distribution model.Toxicity data included represent the response of biota to a range of carbon content (3%–48%) and to the composition of fuel at various stages of degradation (from fresh to 18 months aged) in soils as occurs at contaminated sites on Macquarie Island.The methodology for guideline derivation and the EQGVs provided will be integral to the implementation of future cleanup activities across Australia's contaminated sites in the sub‐Antarctic and Antarctic and are recommended for use more broadly across this polar region. [ABSTRACT FROM AUTHOR]

The study of the variability of soil gas concentrations is crucial for defining effective monitoring and remediation strategies and for the risk assessment related to the emission of vapors from the subsurface. The traditional soil gas monitoring strategy consists of seasonal surveys based on short‐time‐averaged sampling. Soil gas monitoring results are often used to assess the risk associated with the emission of volatile contaminants from the subsurface, using models mainly based on molecular diffusion and therefore assuming continuous emission from the soil. At two contaminated sites located in the Veneto region (Italy), continuous monitoring using a photoionization detector, pressure gauges, and an ultrasonic anemometer was used to relate soil gas variability to surface and subsurface physical parameters. At both sites a cyclic diurnal variation of volatile organic compounds concentration in soil gas was observed, correlated with the variation of several meteorological parameters and in particular with the variation of the differential pressure between soil and atmosphere and the buoyancy vertical flux. These findings question the reliability of the conventional methodology employed in the collection and assessment of soil gas data. Integr Environ Assess Manag 2024;20:2023–2032. © 2024 SETAC Key Points: Continuous monitoring at the two study sites showed that the cyclic variation of VOC concentration in soil gas correlated with the variation of differential pressure and buoyancy vertical flux.As evidenced by the differential pressure measurements conducted in this study, there is an alternation of nonemission phases, and phases in which the soil gas emission from soil to atmosphere may be enhanced due to pressure‐driven advective fluxes.The findings raise questions about the reliability of the conventional methodology employed in the collection and assessment of soil gas data. [ABSTRACT FROM AUTHOR]

In situ chemical oxidation (ISCO) is commonly used for the remediation of contaminated sites, and molecular oxygen (O2) after activation by aquifer constituents and artificial remediation agents has displayed potential for efficient and selective removal of soil and groundwater contaminants via ISCO. In particular, Fe-based materials are actively investigated for O2 activation due to their prominent catalytic performance, wide availability, and environmental compatibility. This review provides a timely overview on O2 activation by Fe-based materials (including zero-valent iron-based materials, iron sulfides, iron (oxyhydr)oxides, and Fe-containing clay minerals) for degradation of organic pollutants. The mechanisms of O2 activation are systematically summarized, including the electron transfer pathways, reactive oxygen species formation, and the transformation of the materials during O2 activation, highlighting the effects of the coordination state of Fe atoms on the capability of the materials to activate O2. In addition, the key factors influencing the O2 activation process are analyzed, particularly the effects of organic ligands. This review deepens our understanding of the mechanisms of O2 activation by Fe-based materials and provides further insights into the application of this process for in situ remediation of organic-contaminated sites. [ABSTRACT FROM AUTHOR]

Tilapia is a model fish species used as a pollution biomonitor due to its tolerance and availability in many contaminated sites. Blue tilapia Oreochromis aureus specimens (n = 320) were collected in eleven dams influenced by mining in the SE Gulf of California region (dams 1, 2 and, 3 comprise 55 mining sites; dam 4 comprises 8; dams 6, 8, 10, and 11, ≤ 6; and dams 5, 7, and 9 include 19, 20, and 16 mining sites, respectively). Cadmium, Cu, Pb, and Zn concentrations were analyzed in the muscle, liver, gills, and guts to identify metal pollution and evaluate risks and seasonal changes. The distinct tissues exhibited different metal accumulation capacities, therefore allowed develop a diagnosis comparative between the eleven dams. In general, metal concentrations were higher in dams 1, 2, 5, and 9, which are associated with more mining sites in their sub-basins. The four metals exhibited the highest levels in the tilapia liver in dams 1 and 2, which can be related to the present and past mining activity in the lower watershed (55 sites) and the geothermal activity in these dams. In general, Zn exhibited the highest level in the tilapia livers from dams 1, 2, 3, 4, 5, and 10 compared to the maximum mean (220 µg/g) concentrations previously recorded. The non-carcinogenic risks indicated that the Pb risk was enhanced when the intake was ≥ 231.5 g week−1 of tilapia muscle, indicating a potential risk of adverse health effects for the entire population. [ABSTRACT FROM AUTHOR]

Multilayer composite soil chamber was proposed to extract the Cr of contaminated site soil and insight into transformation of Cr fractionation associated with valence states. The variations of current, soil pH and moisture content were explored, as well as the migration of Cr fractionation and redistribution of Cr. Results indicated that duration of half peak current could be used to adjust treatment time and it varied among different composite ways. Moreover, extraction efficiency of Cr in soil near cathode was relatively higher and reached 60% when citric acid was used. Citric acid could promote the transformation between different Cr fractionations or different valence states. It could also improve the desorption of Cr, and could prevent excessive fluctuations of moisture content at the same time. Cr redistributed acrossed the soil chamber after extraction. When deionized water was used, Cr(VI) significantly migrated toward anode mainly in the form of exchangeable fractionation (EXC) while Fe–Mn oxides fractionation (Fe–Mn) which may be in the form of cationic Cr(III) hydroxides migrated toward cathode. When using citric acid, fractionations that were difficult to migrate of Cr, especially for Fe–Mn in site soils could be activated and became EXC and carbonate fractionation (CAR), then migrated to the anode or cathode. The migration of exchangeable Cr(III) was dramatically enhanced. But the use of citric acid could cause Cr(VI) transformation to Cr(III) near anode. In addition, during the migration process, EXC could go back to Fe–Mn again or transform to residue fractionation (RES). [ABSTRACT FROM AUTHOR]

The risk of arsenic contamination is rising globally, and it has negative impacts on the physiological processes and growth of plants. Metal removal from contaminated soils can be accomplished affordably and effectively with plant growth promoting rhizobacteria (PGPR)-based microbial management. From this angle, this research evaluated the mitigation of arsenic toxicity using the bacteria isolated from contaminated site, Mettur, Salem district, South India. The newly isolated bacterial strain was screened for plant growth promotion potential and arsenic tolerance such as (100 ppm, 250 ppm, 500 ppm, 800 ppm and 1200 ppm). The metal tolerant rhizobacteria was identified using 16S rRNA gene sequence analysis as Pseudomonas alcaliphila strain PAS1 (GenBank accession number: OQ804624). Pigeon pea (Cajanus cajan) plants were used in pot culture experiments with varying concentrations of arsenic, (5 ppm, 10 ppm and 25 ppm) both with and without bacterial culture, for a period of 45 days. At the concentration of 25 ppm after the application of PAS1 enhanced the plant growth, protein and carbohydrate by 35.69%, 18.31% respectively. Interestingly, P. alcaliphila strain PAS1 significantly reduced the stress-induced elevated levels of proline, flavonoid, phenol and antioxidant enzyme in pigeon pea plants was 40%, 31.11%, 27.80% and 20.12%, respectively. Consequently, PAS1 may significantly reduce the adverse effects that arsenic causes to plant development in acidic soils, improve plant uptake of nutrients, and increase plant production. The findings of this study reveal that P. alcaliphila PAS1 is intrinsic for phytoremediation by reducing arsenic accumulation in the root and shoot. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) play an essential role in plant growth and have great potential to enhance plant tolerance under polluted and toxic conditions. This study deals with a survey of five contaminated sites of the Baddi Barotiwala Nalagarh (BBN) industrial corridor/hub to investigate the morpho-diversity of endotrophic AM fungi associated with native plants. The high contamination factor of Cd and Fe in different study sites revealed a high intensity of contamination, indicating that the sites were significantly polluted with Cd and Fe. Results showed that AM symbioses were successfully established in the roots of native plants, highlighting their role in mitigating the harmful effects of potentially toxic elements (PTEs) through bioremediation. A total of 50 AMF morphotypes across 9 genera (Acaulospora, Entrophospora, Ambispora, Diversispora, Gigaspora, Scutellospora, Glomus, Rhizophagus, and Sclerocystis) were identified, with Glomeraceae being the most abundant (46%), followed by Acaulosporaceae (39%) and others contributing less (15%). The study also indicated that the hyphal and vesicular infections were prominent than arbuscular infections in roots. This is the first report on the diversity of native and putative AMF species associated with plants in the BBN industrial corridor, suggesting that these fungi could be cultured for further use as a sustainable organic approach in agriculture and rehabilitation practices in polluted areas. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the distribution of organochlorine pesticides in the Loktak Lake and its draining rivers over a spatial and seasonal scale. Organochlorine pesticides including α- HCH, β- HCH, γ- HCH, δ- HCH, Aldrin, 4,4-DDE, Endrin, Endosulfan II, 4,4-DDD, Endrin Aldehyde, Endosulfan sulphate and 4,4-DDT were analysed in the water and sediments adopting gas chromatography and mass spectrometric techniques. The concentration of pesticides recorded the highest concentration of 2271 ng/l in the water samples and 5319 ng/g in sediment samples. In water samples, Endosulfan II, Endrin and γ- HCH were present at the higher concentrations, whereas α-BHC was recorded at the lowest at 0.78 ng/l. In sediment samples, 4, 4-DDT recorded the highest concentration, followed by 4,4-DDD and Endosulfan II. Human health risk assessment based on water consumption shows higher risk potential from five pesticides. Pesticides in the region may pose a threat to the wetland comprising vital flora and fauna of the biodiversity hotspot. The bacterial population was more or less related to the pesticide concentration, with a lower population at less contaminated sites. [ABSTRACT FROM AUTHOR]

Survival and reproduction tests were conducted using two native springtail (subclass: Collembola) species to determine the toxicity of a fine-grained (< 0.005 – 0.425 mm) soil from an industrial site located in the Canadian boreal ecozone. Accidental petroleum hydrocarbon (PHC) release continuously occurred at this site until 1998, resulting in a total hydrocarbon concentration of 12,800 mg/kg (soil dry weight). Subfractions of the PHC-contaminated soil were characterized using Canadian Council of Ministers of the Environment Fractions, which are based on effective carbon numbers (nC). Fraction 2 (> nC10 to nC16) was measured at 8400 mg/kg and Fraction 3 (> nC16 to nC34) at 4250 mg/kg in the contaminated soil. Age-synchronized colonies of Folsomia candida and Proisotoma minuta were subject to 0%, 25%, 50%, 75%, and 100% relative contamination mixtures of the PHC-contaminated and background site soil (< 100 mg/kg total PHCs) for 28 and 21 days, respectively. Survival and reproduction decreased significantly (Kruskal–Wallis Tests: p < 0.05, df = 4.0) in treatments of the contaminated site soil compared to the background soil. In both species, the most significant decline in survival and reproduction occurred between the 0% and 25% contaminated soil. Toxicity responses in the two springtails were ascribed to the standardized test design, short lifespans, and high fecundity in both species. This study showed that 25 + years of soil weathering has not eliminated the toxicity of fine-grained PHC-contaminated soil on two native terrestrial springtail species. Adverse effects to springtail health were attributed to exposure to soils dominated by genotoxic PHC Fraction 2 compounds and slow weathering processes due to the cold climate at the site. [ABSTRACT FROM AUTHOR]

Phytoremediation technology utilises the ability of plants to remove metal toxicity in the soil. Bamboo is one of the fast-growing woody plants that may potentially facilitate the immediate removal of toxic metals from the soil. This study was conducted to identify the potential of Dendrocalamus asper in phytofiltering metal elements from the mining sites such as the Chini watershed in Pahang. Dendrocalamus asper was grown in a greenhouse with several applications of bamboo biochar (BB) and EDTA in addition to the efficiency test in reducing soil contaminants for 100 days. The present study found Dendrocalamus asper with the addition of BB+EDTA had reduced 37.44% Fe, 43.72% As, 79.27% Pb, 22.67% Cd, and 48.60% Al concentration in the soil. The same treatment also showed a higher plant accumulation of metal concentrations Pb (31-fold) followed by Al (1.3-fold), Cr (1.3-fold), As (1.05-fold), Fe (82%) and Cd (81%) compared to the control. Growing bamboo with the combination of BB+EDTA was found to be useful for Pb phytoextraction and suitable as a phytostabiliser for Al, Fe, As, Cr and Cd. The understanding in the potential of Dendrocalamus asper in reducing soil contaminants may benefit stakeholders in managing and r estoring contaminated sites in the fut ure. [ABSTRACT FROM AUTHOR]

Simple Summary: Mercury is one of the most common pollutants in agricultural and industrial areas; therefore, its study has become increasingly important. This element is often quantified using biomonitors, whose gradual response is representative of the entire community. This is especially important in areas where pollution is known or suspected, like the Mezquital Valley in central Mexico. Here, we aimed to determine the total mercury concentration in three species of small wild mammals that differ in diet to identify possible exposure threats in their habitat. We took hair and liver samples from two bat species and one wild mouse species over the course of a year. We found no difference in mercury concentration among species, but liver mercury was significantly lower during the dry season. This supports previous studies that pointed to wastewater as the main source of mercury exposure in this location. This is the first study to use small wild mammals as biomonitors in the Mezquital Valley, which is a critically contaminated site, as well as the first record of toxic metals in the protected bat species Leptonycteris yerbabuenae. Mercury (Hg) has been extensively studied due to its impact on the environment and health, but its effects on wild mammal populations are still poorly known. Therefore, the use of biomonitors has gained importance. Our objective was to report and compare, for the first time, the amount of mercury in small mammals belonging to three trophic guilds and to provide an initial toxicology perspective in the Mezquital Valley, a critically polluted area of Central Mexico. We quantified total Hg from the hair and liver of a nectarivorous bat (Leptonycteris yerbabuenae), an insectivorous bat (Corynorhinus townsendii) and a granivorous mouse (Peromyscus melanophrys) using atomic absorption spectrometry during the dry and rainy seasons. We compared the mercury concentrations between seasons, species and matrices. In all species, the average mercury content was higher in hair than liver, and there was no correlation between matrices. There was no difference in mercury content among species. Hg concentrations in the livers of P. melanophrys and C. townsendii were lower during the dry season than the rainy season, suggesting a seasonal decline in mercury availability. All of the values detected were below the neurotoxicity threshold reported in small mammals (10 ppm); however, we propose constant monitoring of Hg in their environment and confirm the utility of these species as biomonitors. [ABSTRACT FROM AUTHOR]

Environmental contamination of aquatic systems by per‐ and polyfluoroalkyl substances (PFAS) has generated significant health concerns. Remediation of contaminated sites such as the fire‐fighting emergency training grounds that use aqueous film‐forming foams is a high priority. Phytoremediation may help play a part in removing PFAS from such contaminated waters. We investigated the potential of the water fern Azolla filiculoides, which is used for phytoremediation of a wide range of contaminants, to uptake seven common PFAS (perfluorobutanoic acid [PFBA], perfluorobutane sulfonic acid [PFBS], perfluoroheptanoic acid [PFHpA], perfluorohexanoic acid [PFHxA], perfluorohexane sulfonic acid [PFHxS], perfluorooctanoic acid [PFOA], and perfluoropentanoic acid [PFPeA]), during a 12‐day exposure to environmentally relevant concentrations delivered as equimolar mixtures: low (∑PFAS = 0.0123 ± 1.89 μmol L−1), medium (∑PFAS = 0.123 ± 2.88 μmol L−1), and high (∑PFAS = 1.39 μmol L−1) treatments, equivalent to approximately 5, 50, and 500 µg L−1 total PFAS, respectively. The possible phytotoxic effects of PFAS were measured at 3‐day intervals using chlorophyll a content, photosystem II efficiency (Fv/Fm), performance index, and specific growth rate. The PFAS concentrations in plant tissue and water were also measured every 3 days using ultra‐high‐performance liquid chromatography—tandem mass spectrometry. Treatments with PFAS did not lead to any detectable phytotoxic effects. All seven PFAS were detected in plant tissue, with the greatest uptake occurring during the first 6 days of exposure. After 12 days of exposure, a maximum bioconcentration factor was recorded for PFBA of 1.30 and a minimum of 0.192 for PFBS. Consequently, the application of Azolla spp. as a stand‐alone system for phytoremediation of PFAS in aquatic environments is not sufficient to substantially reduce PFAS concentrations. Environ Toxicol Chem 2024;43:2157–2168. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Hazardous waste treatment facilities are modified and specialized facilities constructed to safely deal with hazardous waste resources, which pose important risks to human health and the situation due to their physical, chemical, and biological properties. In this manuscript, we compute the novel technique of propositional picture fuzzy 2-tuple linguistic (PPF2-TL) set, where the grades in PPF2-TL sets are linked with each other with the help of parameters. Further, some algebraic operational laws and Aczel-Alsina operational laws for PPF2-TL values are presented. Moreover, we describe the technique of PPF2-TL Aczel-Alsina power averaging (PPF2-TLAAPA) operator, PPF2-TL Aczel-Alsina power weighted averaging (PPF2-TLAAPWA) operator, PPF2-TL Aczel-Alsina power geometric (PPF2-TLAAPG) operator, PPF2-TL Aczel-Alsina power weighted geometric (PPF2-TLAAPWG) operator, and their basic properties. Additionally, we evaluate the model of technique for order of preference by similarity to the ideal solution (TOPSIS) method and weighted aggregates sum product assessment (WASPAS) method by using the initiated operators and measures. Further, we resolve the problem of hazardous waste treatment facilities by using the technique of multi-attribute decision-making (MADM) method to enhance the worth of the proposed theory. Finally, we illustrate some examples for comparing the initiated ranking values with some existing ranking techniques to show the supremacy and flexibility of the proposed ranking techniques. [ABSTRACT FROM AUTHOR]

Copyright of Firat University Journal of Experimental & Computational Engineering (FUJECE) is the property of Firat University Journal of Experimental & Computational Engineering (FUJECE) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At the Gowanus Canal Superfund site in Brooklyn, New York, a multilayer reactive capping system is required as part of the approved remedy. The base reactive layer is an organoclay (OC)–sand layer containing a minimum of 25% by dry weight OC that is intended to block any upwelling mobile nonaqueous phase liquids (NAPLs). The construction quality assurance (CQA) method for verifying the OC content of the OC–sand stockpiles prior to placement in the canal consists of Loss on Ignition (LOI) testing performed at an offsite laboratory with a turnaround time of 3 days. To mitigate construction delays, rapid field testing methods to verify the OC content of the OC–sand blends were sought. Interestingly, electrical conductivity (EC) measurements on the as-is (not sieved or pulverized) OC, sand, and their blends provided several correlations with goodness of fit (R2) values >0.95 for a variety of sand-sized materials including: a commercial playground sand, beach sand, a limestone quarry sourced sand, and the sediment capping sand from the first Remedial Target Area (RTA-1) at the Gowanus Canal. The correlation curves and R2 values were relatively insensitive to change in the sand borrow source (silicate or karst geology or salinity). EC measurements were available in as little as 30 min and up to approximately 24 h using a tabletop pH/EC probe, distilled water, beaker, and magnetic stirrer. The EC approach and preliminary correlations presented here can greatly reduce CQA testing turnaround times to within hours (not days) in field settings. Lastly, similar findings were made when another commercially modified bentonite clay known as Fluorosorb-400™ was blended with playground sand. [ABSTRACT FROM AUTHOR]

Environmental contamination with Bacillus anthracis spores poses clear threats to livestock that play key roles in the economies of pastoral communities. Regular monitoring of contaminated sites is particularly important in anthrax-endemic parts of the world, such as Kars province in eastern Türkiye, where the Veterinary Microbiology Department of Kafkas University has conducted an anthrax surveillance programme for over 30 years. We reviewed the microbiological results of 232 soil samples collected during 2009–2023, from sites known to be contaminated with B. anthracis spores following burial or butchering of infected animal carcasses. Twenty-five contaminated sites in 16 villages were studied. Samples were taken from a total of 61 different positions within these sites and viable spores were detected in 136 (58.6%) of the samples examined. Of the 96 samples from which spores were not recovered, subsequent samples from the same positions proved positive on 21 occasions. Using a standardised sampling plan, it was discovered that samples taken 1–2 m on a downward slope from the centre-point of contamination had higher (p < 0.001) spore concentrations than those taken from other positions. Although spore concentrations at some sampling positions varied over time, the overall values remained stable. This finding contrasts with observations in other parts of the world where spore concentrations tend to decline with time and may reflect regional differences in soil composition that permit more prolonged spore persistence. Concentrations of >100 spores/g soil were found in 10 (66.7%) of the 15 samples taken 10–13 years following a contamination event. These results demonstrate the longevity of viable anthrax spores in the soil of agricultural environments following decomposition of infected animal carcasses, and therefore the need for prolonged bacteriological monitoring of contaminated sites. Furthermore, they underline the importance of appropriate decontamination, as burial on its own does not eliminate all spores. [ABSTRACT FROM AUTHOR]

This paper addresses the transformation of the region around the twin-town Bitterfeld-Wolfen in Eastern Germany from a highly polluted industrial hub into a lakeland idyll and destination for recreation and nature-based tourism. From the perspective of local residents of age, the significance of this transformation was fundamentally shaped by German reunification, in particular by the experience of stigmatisation related to high levels of pollution in Bitterfeld-Wolfen in the context of general bias that devalued East German subjectivities in the course of German reunification. As I detail through both historical and ethnographic research, I show how mine restoration and the clean-up of contaminated sites have subsequently acquired meaning beyond ecological recovery and the improvement of public health. Tied up with the uncertainties and ambivalences of the transformation of East Germany and its integration into a West German entity, I demonstrate how the (im)possibility of restoring a destroyed landscape became inseparable from the postulated need of fundamental recovery of an East German region and its inhabitants from, so-perceived, socialist ruination. Consequently, I argue, the clean-up of contaminated sites and the remediation of a large open-cast mine in (former) East Germany produced not only an idyllic post-mining landscape, but a post-socialist one. Furthermore, as an archive of local history, the restored landscape became a way for elderly people to re-appropriate their past through its transformation into a remarkable present. In tracing this contested history, this paper contributes to landscape-centred analyses of post-socialist transformations in Europe. [ABSTRACT FROM AUTHOR]

Much attention is placed on organohalide-respiring bacteria (OHRB), such as Dehalococcoides, during the design and performance monitoring of chlorinated solvent bioremediation systems. However, many OHRB cannot function effectively without the support of a diverse group of other microbial community members (MCMs), who play key roles fermenting organic matter into more readily useable electron donors, producing corrinoids such as vitamin B12, or facilitating other important metabolic processes or biochemical reactions. While it is known that certain MCMs support dechlorination, a metric considering their contribution to bioremediation performance has yet to be proposed. Advances in molecular biology tools offer an opportunity to better understand the presence and activity of specific microbes, and their relation to bioremediation performance. In this paper, we test the hypothesis that a specific microbial consortium identified within 16S ribosomal ribonucleic acid (rRNA) gene next generation sequencing (NGS) data can be predictive of contaminant degradation rates. Field-based data from multiple contaminated sites indicate that increasing relative abundance of specific MCMs correlates with increasing first-order degradation rates. Based on these results, we present a framework for computing a simplified metric using NGS data, the Microbial Community Structure Index, to evaluate the adequacy of the microbial ecosystem during assessment of bioremediation performance. [ABSTRACT FROM AUTHOR]

Developing efficient and sustainable pollution control technologies has become a research priority in the context of escalating global environmental pollution. Nano zero-valent iron (nZVI), with its high specific surface area and strong reducing power, demonstrates remarkable performance in pollutant removal. Still, its application is limited by issues such as oxidation, passivation, and particle aggregation. White rot fungi (WRF) possess a unique enzyme system that enables them to degrade a wide range of pollutants effectively, yet they face challenges such as long degradation cycles and low degradation efficiency. Despite the significant role of nZVI in pollutant remediation, most contaminated sites still rely on microbial remediation as a concurrent or ultimate treatment method to achieve remediation goals. The synergistic combination of nZVI and WRF can leverage their respective advantages, thereby enhancing pollution control efficiency. This paper reviews the mechanisms, advantages, and disadvantages of nZVI and WRF in pollution control, lists application examples, and discusses their synergistic application in pollution control, highlighting their potential in pollutant remediation and providing new insights for combined pollutant treatment. However, research on the combined use of nZVI and WRF for pollutant remediation is still relatively scarce, necessitating a deeper understanding of their synergistic potential and further exploration of their cooperative interactions. [ABSTRACT FROM AUTHOR]

Exposures to pollutants and contaminants can occur through water or soil, which can be contaminated naturally or through human activities. The toxicity and adverse health effects of these substances depend on exposure route, quantity, and duration. Mechanisms of water contamination include runoff, flooding, infrastructure failures, and contamination from air and surface water pollution. Pesticides and organophosphates commonly are used in agricultural and residential applications, frequently cause water contamination, and commonly cause poisoning in agricultural workers and gardeners. Soil contamination disproportionately affects minority and low-income populations because they are more likely to live in proximity to a pollution source. Fetuses, children, and individuals with preexisting medical conditions are more vulnerable to adverse health effects of soil contamination compared with healthy adults. Some of the most common soil pollutants are heavy metals, pesticides, and polychlorinated biphenyls. Preventing exposure to contaminated soil involves avoidance of historically contaminated sites and ingestion of soil. Approaches to cleanup depend on the extent of contamination, location, and planned future use of the land. Remediation strategies include containment, bioremediation, chemical oxidation, soil washing, and thermal treatment. [ABSTRACT FROM AUTHOR]

[Objective] Concerning interdisciplinary research, the use of chemicals in colleges and universities is expanding, presenting considerable challenges for standardized management. National laws and regulations require stringent verification and registration systems for importing and exporting hazardous chemicals, ensuring control throughout their use cycle. This includes maintaining records from purchase requests to receipt, use, recovery, and destruction, which ensures consistency between inventory materials and usage records. However, managing chemicals in colleges and universities is complicated by practical factors such as multiple usage types, small stock of single products, wide professional coverage, and dispersed storage areas. These factors make real-time accounting, scientific classification, and storage in the actual management process difficult. Therefore, to address the challenge of building a chemical cloud platform based on data fusion, aligning with national requirements and the specific needs of schools is essential. The goal is to achieve comprehensive real-time supervision of chemicals throughout their lifecycle. [Methods] A real-time chemical management system is developed using data fusion technology. This system organizes the three-party, four-dimensional, and multilevel data matrix involved in chemical management. It integrates multisource, multiform, and multilevel data flows from procurement, process management, storage cabinet monitoring, hazardous waste disposal, and regulatory management. Through series, splicing, and aggregation, multisource data are shared and integrated, thereby creating a unified dataset via feature extraction. This approach provides access to comprehensive chemical management data and supports fast calculations, real-time supervision, and intelligent notifications. [Results] By integrating data fusion technology into the chemical management system, focusing on source control, inventory limitation, intelligent supervision, and quality improvement as the path, a comprehensive framework has been established. This includes the development of software and hardware for a single body, two wings, and multiple fulcrum chemical management models. Key achievements include the creation of a cloud mall for chemical purchases and a cloud platform for the entire process management. Additionally, university-level reagent and hazardous waste storage facilities have been built, and smart chemical storage cabinets have been purchased in batches. [Conclusions] Leveraging data characteristics and full data integration, the chemical real-time management system now centers around a two-dimensional code approach as the core. This system enables real-time management system construction of scanning code opening, scanning code storage, timely weighing, and automatic accounting. Enhanced safety measures, improved management team, rigorous supervision and inspection, and upgraded facility configurations ensure comprehensive data management of chemicals from purchase to disposal. This setup allows for real-time supervision of chemical usage. [ABSTRACT FROM AUTHOR]

The global concern for risk control of organic contaminated sites is becoming more and more prominent. Traditional ex situ remediation techniques are costly and damage the site, seriously destroying the soil structure and ecological functions. Therefore, in situ means of combining material injection and microbial remediation have become a potential pathway for the green, economical, and efficient remediation of contaminated sites. In this work, a 200 m2 test block was selected for the coupled injection of slow-release oxygen materials and microbial agents, and long-term monitoring of groundwater was carried out. The results showed that the slow-release materials could release oxygen for a period of 90 days, which provided an oxidizing environment for microorganisms to rapidly degrade BTEX. For the pre-adapted indigenous degradation bacterial agent test group, the degradation degree of BTEX was up to 98% after 40 days of injection. The results of the application on the field scale proved the feasibility of reinforcing biostimulation for remediation of underground organic contamination through the coupled injection of slow-release oxygen materials and microbial agents. The results provided theoretical and technical support for the in situ remediation of petroleum hydrocarbon-contaminated sites. [ABSTRACT FROM AUTHOR]

There have been reports of potential health risks for people from hydrophobic organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated hydrocarbons (PCHs), and organophosphate flame retardants (OPFRs). When a contaminated site is used for residential housing or public utility and recreation areas, the soil-bound organic pollutants might pose a threat to human health. In this study, we investigated the contamination profiles and potential risks to human health of 15 PAHs, 6 PCHs, and 12 OPFRs in soils from four contaminated sites in China. We used an in vitro method to determine the oral bioaccessibility of soil pollutants. Total PAHs were found at concentrations ranging from 26.4 ng/g to 987 ng/g. PCHs (0.27‒14.3 ng/g) and OPFRs (6.30‒310 ng/g) were detected, but at low levels compared to earlier reports. The levels of PAHs, PCHs, and OPFRs released from contaminated soils into simulated gastrointestinal fluids ranged from 1.74% to 91.0%, 2.51% to 39.6%, and 1.37% to 96.9%, respectively. Based on both spiked and unspiked samples, we found that the oral bioaccessibility of pollutants was correlated with their log K ow and molecular weight, and the total organic carbon content and pH of soils. PAHs in 13 out of 38 contaminated soil samples posed potential high risks to children. When considering oral bioaccessibility, nine soils still posed potential risks, while the risks in the remaining soils became negligible. The contribution of this paper is that it corrects the health risk of soil-bound organic pollutants by detecting bioaccessibility in actual soils from different contaminated sites. [Display omitted] [ABSTRACT FROM AUTHOR]

A large number of publications have been devoted to the study of aerosol atmospheric transport, but the low-temperature transfer of metals and metalloids as a part of gas flow remains poorly understood. The present work is devoted to the study of gas stream composition using an approach based on the collection of nascent condensate upon cooling of the air flow formed over the surface of contaminated sites. A special laboratory unit was designed to collect the condensate followed by the study of its composition using atomic emission and mass spectrometry. The main novelty of this work consists of the application of the single-particle ICP‒MS technique to obtain qualitative information concerning the state of the elements in the condensates. Gold and silver are most likely present in the samples as nanoparticles; arsenic, selenium, tin and lead are present both as nanoparticles and as soluble forms; and barium and mercury are present only in soluble forms. The condensed phase contains As, Hg, Au, Ag, Pb and Sn at the ppb level, while the main elements of the tailings material (Fe, Ba, Cu, Zn and others) are present at the ppm level, which exceeds the background concentration. [ABSTRACT FROM AUTHOR]

The fate of light non-aqueous phase liquids (LNAPLs) is significantly influenced by complex characteristics of actual soils in unsaturated zone. To systematically analyze the multiphase migration process of LNAPLs in such soils, a two-dimensional laboratory device was designed to conduct benzene injection and water leaching experiments in three soil types of silty loam, loam and sandy loam that collected from a chemical industrial park in China. In the unsaturated zone, the jagged and asymmetric edges of pollution halo were observed attributed to heterogeneity in the small pores of the sampled soils. Additionally, low permeability also resulted in a high horizontal-to-vertical ratio of above 2.2. Based on laboratory experiments, a numerical model was established to simulate multiphase fluid migration, volatilization, dissolution and adsorption processes. The measured values closely matched the simulated values. The simulation results indicated that that over 99% of benzene was entrapped, with less than 1% volatilizing during the benzene injection stage in the unsaturated zone. During the leaching process, a portion of the benzene dissolved with the water flow, accounting for 1.557–4.786%. Compared to volatilization, dissolution played a more significant role in mass transfer processes. Combined with the laboratory experiments and numerical models, this conclusion elucidates the mechanism of multiphase distribution of LNAPLs in actual sampled soils. These findings provide a theoretical basis for developing reasonable and effective remediation methods for actual contaminated sites. [ABSTRACT FROM AUTHOR]

Emerging contaminants (ECs) present a significant risk to both the ecological environment and human health. Landfill leachate (LL) often contains elevated EC levels, posing a potential risk to localized groundwater. This study aimed to characterize ECs in municipal solid waste landfills (MSWLs) and hazardous waste landfills (HWLs) in northeast (NE) China. One and three HWLs and MSWLs in NE China with varying types, operational years, and impermeable layers were selected as case studies, respectively. Statistical analysis of 62 indicators of nine ECs in leachate and the groundwater environment indicated the presence of perfluorinated compounds (PFCs), antibiotics, alkylphenols (APs), and bisphenol A (BPA). The leachates of the four landfills exhibited elevated concentrations of ECs of 21.03 μg/L, 40.04 μg/L, 14.54 μg/L, and 43.05 μg/L for PFCs, antibiotics, Aps, and BPA, respectively. There was a positive correlation between the highest concentrations of ECs in groundwater and those in leachate as well as with operational duration of the landfill; in contrast, groundwater EC was negatively correlated with the degree of impermeability. This study can guide future management of ECs in landfills and hazardous waste sites in China, particularly in NE China. [ABSTRACT FROM AUTHOR]

African American (AA) women confront distinct disparities in breast cancer rates, and the impact of their living environment is unclear. This study aimed to examine the association between breast cancer incidence and environmental factors among a high-risk female population. The study recruited 355 AA women ages 20–88 in Memphis from 2016–2018. Their addresses were geocoded and linked to environmental and socioeconomic data. The final dataset contained 50 cases and 157 controls. Associations between breast cancer incidence and social and environmental factors were examined using logistic regression. Spatial analysis in ArcGIS showed that cases clustered in Southwest Memphis. Proximity to traffic and Superfund sites had odds ratios of 1.636 (95% CI: 25 1.046, 2.560) and 12.262 (95% CI: 1.814, 82.864), respectively. Mediating analyses further revealed that environmental inequities contributed significantly to breast cancer inequalities. In conclusion, the built environment plays a role in breast cancer onset among AA females. [ABSTRACT FROM AUTHOR]

Erosion and leaching of metal(loid)s from contaminated sites can spread pollution to adjacent ecosystems and be a source of toxicity for living organisms. Phytostabilization consists of selecting plant species accumulating little or no metal(loid)s in aerial parts to establish a vegetation cover and thus to stabilize the contaminants in the soil. Seeds of white lupin, common vetch, and buckwheat were sown in greenhouse on soils from former French mines (Pontgibaud and Vaulry) contaminated with metal(loid)s including high concentrations of As and Pb (772 to 1064 and 121 to 12,340 mg kg−1, respectively). After 3 weeks of exposure, the growth of white lupin was less affected than that of the 2 other species probably because metal(loid) concentrations in roots and aerial parts of lupins were lower (5–20 times less Pb in lupin leaves on Pontgibaud soil and 5–10 times less As in lupin leaves on Vaulry soil than in vetch and buckwheat). To limit oxidation and/or scavenge metal(loid)s, white lupin increased the content of proline and total phenolic compounds (TPC) in leaves and roots by a factor 2 whereas buckwheat stimulated the production of TPC by a factor 1.5–2, and non-protein thiols (NPT) by factors around 1.75 in leaves and 6–12 in roots. Vetch accumulated more proline than white lupin but less NPT than buckwheat and less TPC than the 2 other plant species. The level of oxidation was however higher than in control plants for the 3 species indicating that defense mechanisms were not completely effective. Overall, our results showed that white lupin was the best species for phytostabilization but amendments should be tested to improve its tolerance to metal(loid)s. [ABSTRACT FROM AUTHOR]

Crude oil contamination has been widely recognized as a major environmental issue due to its various adverse effects. The use of inhabitant microorganisms (native to the contaminated sites) to detoxify/remove pollutants owing to their diverse metabolic capabilities is an evolving method for the removal/degradation of petroleum industry contaminants. The present study deals with the exploitation of native resident bacteria from crude oil contaminated site (oil exploration field) for bioremediation procedures. Fifteen (out of forty-four) bioremediation-relevant aerobic bacterial strains, belonging to the genera of Bacillus, Stenotrophomonas, Pseudomonas, Paenibacillus, Rhizobium, Burkholderia, and Franconibacter, isolated from crude oil containing sludge, have been selected for the present bioremediation study. Crude oil bioremediation performance of the selected bacterial consortium was assessed using microcosm-based studies. Stimulation of the microbial consortium with nitrogen or phosphorous led to the degradation of 60–70% of total petroleum hydrocarbon (TPH) in 0.25% and 0.5% crude oil experimental sets. CO2 evolution, indicative of crude oil mineralization, was evident with the highest evolution being 28.6 mg mL−1. Ecotoxicity of treated crude oil-containing media was assessed using plant seed germination assay, in which most of the 0.25% and 0.5% treated crude oil sets gave positive results thereby suggesting a reduction in crude oil toxicity. [ABSTRACT FROM AUTHOR]

Since the 1980s, low-permeability slurry trench cutoff walls have been widely constructed as barriers to retard the migration of contaminants. The thickness of the cutoff walls is a key determinant of the wall service life. Through a series of theoretical derivations, simplified methods for determining the flux limit and concentration limit were proposed to determine the thickness of cutoff walls for contaminated sites with constant pollutant flux. The relative errors of both the flux-based and concentration-based methods increase as the breakthrough criterion of the ratio between the specified limit concentration of the contaminant to the source concentration (C*) and the ratio of the limited value of contaminant flux to the constant source flux (F*) increases, with a given Peclet number PL. The maximum relative error reaches 4% and 6% when C* and F* are both 0.1, which covers most practical situations in cutoff wall design. Good agreements of wall thickness were obtained between the proposed simplified methods and analytical solutions via a clear example. The proposed method can efficiently simplify the design process of cutoff walls with high accuracy, providing a basis for containing contaminated sites. [ABSTRACT FROM AUTHOR]

In this study, we utilized the larvae of Cheumatopsyche sp. (Insecta, Trichoptera, Hydropsychidae) as a key component to assess heavy metal contamination in the waters of the Bone River, Gorontalo, Indonesia. To measure the concentrations of heavy metals, specifically lead (Pb), cadmium (Cd), and mercury (Hg), an atomic absorption spectroscopy (AAS) was employed on both river sediments and the entire body of the Cheumatopsyche sp. larvae. Additionally, analysis was conducted using the SEM-EDX method to confirm the absorption of heavy metals in the larvae, particularly in the digestive tract. Sediment and larvae samples were collected from five sampling points along the main river, including reference sites in the upstream area. Our findings revealed that Hg and Cd levels were lower in the sediment compared to those in the larvae, while Pb levels were higher in the sediment. Examination of heavy metals in the digestive tract showed morphological abnormalities in larvae from the most contaminated sites. This research confirmed that Cheumatopsyche sp. larvae effectively absorb heavy metals, particularly Hg, validating their use as bioindicators in heavy metal bioassays. [ABSTRACT FROM AUTHOR]

This study investigated how adding stable manure affected the transport of atrazine within agricultural soils from Kahramanmaraş, Turkey. Based on the batch and miscible-displacement experiments, it was found that atrazine sorption was nonlinear, following a Freundlich isotherm, and was rate-limited and reversible for both the non-amended and amended soil. The addition of manure resulted in higher retardation of atrazine, with R values of 10.1 to 19.1, compared to values of 3.2 to 4.3 for the non-amended soil. The KF values for stable-manure amended soil calculated from batch experiment was three times higher than non-amended soil. The transportation of atrazine shows non-ideal behavior, characterized by significant elution tailing at low concentrations due to the organic carbon content of the soil. This effect was more prominent in soil with a 10% stable-manure amendment. By incorporating non-linear sorption, a two-site transport modeling approach provides a reasonably accurate representation of the atrazine breakthrough curves. The distinct sorption-desorption characteristics of atrazine have significant implications for risk assessment of atrazine-contaminated soil and should be considered in the regulation, management, and remediation of such contaminated sites. [ABSTRACT FROM AUTHOR]

The widespread use of petroleum-based fuels poses a significant environmental problem due to the risks associated with accidental spills. Among the treatments available, phytoremediation is increasingly accepted as an effective and low-cost solution. This study aimed to evaluate the degradation of the aromatic fraction of biodiesel B10 and the soil fertility analysis in artificially contaminated soils treated with phytoremediation. The experimental design consisted of a 3x3 factorial, with three types of soil treatment: control, autoclaved, and planted with C. ensiformis L, and three levels of B10 biodiesel contamination: 0, 1, and 2%, to simulate spills of 30,000 and 60,000 L ha−1. The soil was analyzed at three depths: 0–10, 10–20, and 20–30 cm. The results indicated that aromatic compound degradation after phytoremediation was superior to 92,76% and 88,65% for 1% and 2% B10 soil contamination, respectively. The fuel contamination affected soil fertility, reducing the availability of phosphorus and zinc while increasing the Total Organic Carbon (TOC), pH, and the availability of manganese and iron for plants. NOVELTY STATEMENT: Numerous studies have been carried out on the phytoremediation of soils contaminated with diesel. However, the potential impact of biodiesel-diesel blends on soil fertility has not been fully explored, leading to a critical knowledge gap. This work investigates the novel effects of biodiesel-diesel blends on phytoremediation and soil fertility, allowing us to expand our understanding of the effectiveness of this approach to remediate contaminated sites. [ABSTRACT FROM AUTHOR]

The biochemical response of plants exposed to pesticides and inoculated with microorganisms is of great importance to explore cleaning up strategies for contaminated sites with pyrethroid-based pesticides. We evaluated the effects of a Trichoderma consortium on the biochemical responses of Echinochloa polystachya plants during the removal of a pyrethroid-based pesticide. Plants were inoculated or not with the Trichoderma consortium and exposed to commercial pesticide H24®, based on pyrethroids. Pesticide application resulted in significant reduction in root protein content (58%), but enhanced content of malondialdehyde (MDA) in shoots, superoxide dismutase (SOD) activity in shoots and roots, and catalase (CAT) activity in roots. Inoculation of Trichoderma consortium in E. polystachya exposed to the pesticide resulted in increased protein content in roots and MDA content in shoots (2-fold). Trichoderma consortium improved protein content and SOD activity (140-fold) in plants. Fungal inoculation increased the removal (97.9%) of the pesticide in comparison to the sole effect of plants (33.9%). Results allow further understanding about the responses of the interaction between plants and root-associated fungi to improving the assisted-phytoremediation of solid matrices contaminated with organic pesticides. NOVELTY STATEMENT: This original paper describes the positive role of the Trichoderma sp. consortium on favoring the removal of a pyretrhoid-based pesticide. This is one of first reports on analyzing the influence of a Trichoderma consortium on the oxidative stress and antioxidant response of Echinochloa polystachya in presence of the pesticide. This experimental approach provides a new alternative for further fungal assisted-phytoremediation of a pyretrhoid-based pesticide. [ABSTRACT FROM AUTHOR]

The issues associated with long‐screened wells (LSWs) (and open boreholes) at contaminated sites are well documented in the groundwater literature but are still not fully appreciated in practice. As established in seminal and review papers going back over three decades, the interpretation of sampling results from LSWs is challenging in the presence of vertical hydraulic gradients and borehole flow; furthermore, LSWs allow for vertical redistribution of contamination between aquifer layers. Acknowledgment of these issues has led to the development of new technologies and well designs to enable discrete‐zone monitoring (DZM), yet LSWs remain common for many reasons, for example, as multipurpose wells, for geophysical logging, and (or) as legacy installations. Despite the literature on LSWs and despite the adoption of DZM at many sites, the use of LSWs persists and the challenges of interpreting sampling results from LSWs remain. In this issue paper, we provide a conceptual overview of the problems posed by LSWs and review existing literature and past work to improve the interpretation of sampling in LSWs. We draw on experience from previous studies at the Hanford Site in eastern WA, USA, and use synthetic examples to illustrate key concepts and challenges for interpretation. A recently published analytical modeling framework is used to develop illustrative synthetic examples and demonstrate a workflow for building scientific intuition to understand issues around interpreting samples from LSWs, which is critical to effective characterization and groundwater remediation at sites with LSWs. [ABSTRACT FROM AUTHOR]

High levels of heavy metal contamination in soil present substantial threats to human health and the environment, leading to severe health problems such as neurotoxicity, cancer, kidney issues, chronic obstructive pulmonary disease, and reduced life expectancy. This research aims to identify and analyze heavy metals in soil samples collected from Superfund sites in North Birmingham, Alabama, specifically in affected areas with zip codes 35207 and 35217 and control area 35214. These affected areas were previously used for mining, coal-fired power plants, coke furnaces, smelting, and other potential sources of heavy metal pollution. Laser-induced breakdown spectroscopy (LIBS) was employed to study 60 soil samples systematically collected from affected and control areas. We found that by using LIBS, we could detect arsenic (As), lead (Pb), and manganese (Mn) in all soil samples from the affected areas. The limit of detection (LoD) was 29.5 mg/kg for Pb, 95.5 mg/kg for As, and 327 mg/kg for Mn using specific parameters of the detection system and/or argon gas purging at atmospheric pressure. The results were compared with ICP-MS measurements to validate the accuracy of the LIBS findings. The data showed good linearity for all calibration data at relatively low concentrations and a good correlation with ICP-MS measurements. [ABSTRACT FROM AUTHOR]