Contamination Levels Research Articles

Comparison between the Baltic Sea and Irish Sea level of Cs-137 contamination on benthic, demersal and pelagic fish species

The Irish Sea and the Baltic Sea are nowadays still the two most Cs-137 contaminated Seas worldwide. However, the origins of this contaminations are completely different. While the Baltic Sea was unintentionally contaminated due to global fallout after the accident in the Chernobyl nuclear powerplant in 1986, the Irish sea was intentionally used for low level liquid radioactive waste discharges from the Sellafield nuclear reprocessing facility (called Windscale until 1981) between the 1950s and 1990s. Nowadays, more than 30 years later, it is still possible to detect these contaminations in fish, water and sediments of both seas. Since fish are an important part of the human diet, monitoring Cs-137 levels in fish is essential for assessing the potential radiation exposure to humans. In 2019 and 2020 two surveys were dedicated to study the current levels of radioactive contamination in fish species from both Seas. During both surveys, fish samples were collected and analysed by gamma spectrometry later on. The results show that the average Cs-137 activity in benthic, demersal and pelagic fish species from the Baltic Sea are 2.7, 4.6 and 4.2, respectively, times higher than the corresponding values of the Irish Sea. Based on this and two other comparisons, it is concluded that the Baltic Sea is the most contaminated with Cs-137.

OIL DUST INDICATOR

An oil dust indicator is a crucial component in maintaining the efficiency and longevity of machinery and engines. It serves the dual purpose of monitoring both oil level and contamination levels, particularly from dust and particulate matter. The indicator typically consists of a sensor, a processor unit, and a display or alert mechanism. The sensor, often a combination of optical and pressure sensors, continuously monitors the oil. clarity and level. When dust or other contaminants accumulate in the oil, the sensor detects changes in clarity and triggers an alert. The processor unit interprets these signals and activates the display or alert mechanism, informing operators of the need for maintenance. In addition to indicating the need for oil replacement or cleaning, advanced oil dust indicators can also provide data on the severity of contamination, allowing for proactive maintenance planning. This capability can significantly reduce downtime and maintenance costs while optimizing the performance and lifespan of machinery and engines. Oil dust indicators find applications in various industries, including automotive, manufacturing, and power generation. They play a vital role in ensuring the smooth operation of critical machinery and equipment, making them indispensable tools for maintenance professionals and operators alike. This study proposes an advanced oil dust indicator that incorporates sensors for total dissolved solids (TDS), color, and pH levels to provide comprehensive monitoring of oil quality. Keywords: oil dust detector can sense dust in oil.

Evaluation of parenteral diluent contamination by caprolactam.

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. A leachable cyclic amide (caprolactam) can be found in normal saline (NS) and 5% dextrose in water (D5W) plastic bags widely used in clinical practice if they contain polyamide in a multilayer sheeting. This contamination and the parameters that could influence its content have never been studied in a public work such as a scientific publication. Two independent laboratories validated a caprolactam dosing method and studied contamination levels in several containers. Caprolactam content in multilayer polypropylene/polyamide/polypropylene plastic bags ranged from a mean (SD) of 5.43 (0.21) mg/L (D5W 1,000mL) to 22.83 (1.26) mg/L (NS 50mL). NS and D5W can be intravenously administered with a total daily dose of 3L, corresponding to a minimal daily dose of 16.3mg of caprolactam. The high levels of contamination we have reported and the possibility of administering caprolactam to high-risk patients (eg, neonates, the elderly) should make it imperative for pharmaceutical companies to communicate publicly on the safety of caprolactam.

Properties of ceramic membranes obtained from kaolinitic clay mixed with palm and mango wastes from Cameroon: Application to wastewater treatment from breweries

AbstractThis work focuses on the development of new ceramic membranes based on mixtures of low‐cost and locally available raw materials such as kaolinitic clay and additives such as palm kernel shells and mango seed shells, which are used as pore‐forming agents to increase pore size, and on their efficiencies in rejecting organic and inorganic pollutants from brewery wastewater. The physical and chemical properties of raw materials were characterized via X‐ray diffraction, scanning electron microscopy, differential thermal analysis/thermogravimetry, energy dispersive X‐ray, and Fourier transform infrared spectrophotometry. Sintering was performed at 1100°C, and the permeability and mechanical properties of circular membranes were determined. The membrane filtration operation was used to assess the physicochemical parameters of the wastewater. The membrane composed of 85% kaolinite and 15% mango seed shells showed the best performance. The effective treatment of the breweries wastewater reduced the level of contamination by organic pollutants in the discharge water, with a reduction in concentration from 700 to 14 mg O2 L‒1 of chemical oxygen demand and 250 to 06 mg O2 L‒1 of biological oxygen demand for 5 days, representing elimination rates of 98% and 97.6%, respectively. The treated water is alkaline, with a reduction in pH from 10.79 to 7.77. Suspended matter, turbidity, and electrical conductivity had removal rates of 88%, 90.6%, and 99.8%, respectively. A significant reduction in the salinity of this wastewater contributed to sodium and chloride ion rejection rates of 93% and 79%, respectively, which is an important result for good reuse of the treated water in agriculture and domestic work.

The largest estuary on the planet is not spared from plastic pollution: Case of the St. Lawrence River Estuary

The St. Lawrence River, one of the world's largest estuaries, drains >25 % of the world's freshwater reserves and is affected by various anthropogenic effluents. Although previous studies reported micro- and nanoplastics contamination in the Estuary and Gulf of St. Lawrence (EGSL), this study provides a first evaluation of macroplastic pollution along the north and south shores of the EGSL. Plastic debris categorization was performed according to the OSPAR protocol completed by polymer identification using Fourier-transform infrared spectroscopy. The EGSL appeared ubiquitously contaminated by plastic debris, dominated by single-use plastics primarily made of polypropylene (28 %), polyethylene (25 %) and polystyrene (17 %). The EGSL shores exhibited a mean contamination level of 0.17 ± 0.11 items/m2 and distance to Montreal significantly influenced the distribution of plastic debris. This study provides an essential baseline for implementing local waste reduction and management actions in the St. Lawrence watershed to reduce plastic pollution.

Spatial distribution of PAHs and microbial communities in intertidal sediments of the Pearl River Estuary, South China

The exploration of sediment pollution caused by PAHs and its impact on microbial communities can provide valuable insights for the remediation of sediments. The spatial distribution of PAHs and their impact on the microbial community within the Pearl River Estuary were investigated in this study. The findings revealed that the total concentration ranges of 16 PAHs were between 24.26 and 3075.93 ng/g, with naphthalene, fluorene, and phenanthrene potentially exerting adverse biological effects. More PAHs were found to accumulate in subsurface sediments, and their average accumulation rates gradually decreased as the number of rings in PAHs increased, ranging from 180 % for 2-ring to 36 % for 6-ring. The phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Chloroflexi were found to dominate both surface and subsurface sediments The correlation between microbial genera and PAHs contents was weak in sediments with low levels of PAHs contamination, while a more significant positive relationship was observed in sediments with high levels of PAHs contamination. The physicochemical properties of sediments, such as pH, soil structure and Cu significantly influence bacterial community composition in highly contaminated sediments. Additionally, the network analysis revealed that certain bacterial genera, including Novosphingobium, Robiginitalea and Synechococcus_CC9902, played a pivotal role in the degradation of PAHs. These findings are significant in comprehending the correlation between bacterial communities and environmental factors in intertidal ecosystems, and establish a scientific foundation for bioremediation of intertidal zones.

Light Rare Earth Elements in Freshly Deposited River Sediments of Ganga Alluvial Plain, Northern India: Geogenic Variability and Anthropogenic Influences

ABSTRACT Rare Earth Elements (REE) are the industrial “Vitamins” because of the high-technology based modern uses and their anthropogenic inputs in natural environment, this study mainly focused on Geogenic variability and anthropogenic imprints of Light Rare Earth Elements (LREE), in the recently deposited sediments of the Ganga Alluvial Plain. All the Sediment samples were analyzed by using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). LREE comprises about ~91% of total REE in the Gomati River Sediments and Cerium (300 µg/g) was the most abundant LREE in the bedload sediments. Average LREE concentrations in bedload (170 µg/g) and suspended load (184 µg/g) sediments of the Gomati River were observed higher than the Average Sediments and the World Major Rivers Suspended Sediments and therefore, characterizing the LREE contamination in sediments. This contamination level assessed on the basis of Potential Ecological Risk Assessment (PERI), Contamination Factors (CF), Degree of Contamination (CD) and Geo-accumulation Index (Igeo), the trend of element contamination showed that Sm>La>Pr>Ce>Nd and PERI shows that LREE pose moderate to strong ecological risk, mostly by Pr and Sm in the study area. The spatial and temporal enrichment of LREE in sediments were observed in the Basin since last two decades. This paper mainly highlights the effects of socio-economic development linked modern high-tech processes on LREE contamination in the river sediments and cycling by the sub-tropical fluvial environment of southern Asia; where rivers supply ~30% of the global sediment input to the world’s ocean.

Degradation of pyrene at high concentrations in sediment and the implications for the microbiome in microbial electrochemical systems

The polycyclic aromatic hydrocarbons (PAHs) frequently accumulate in sediments, particularly those near industrial sites. The efficacy of microbial electrochemical systems (MESs) in electricity generation and PAHs degradation is intricately linked to the microbiome’s response to high contaminant levels. Metabolomics and metagenomics were applied to elucidate the impact of a high pyrene concentration on the functional structure and metabolic dynamics of sediment microbiomes within MES. In sediment with a high pyrene concentration, both the electrical output of MES and efficiency of their microbiomes in degrading organic substrates and pyrene were markedly reduced. These conditions were associated with the enrichment of PAH-degrading microorganisms, such as Hydrogenophaga and Flavobacterium. Analyses of metabolites and genetic profiles revealed that metabolic pathways were primarily influenced in MES exposed to low pyrene concentrations whereas fewer metabolic pathways were activated in MES exposed to high concentrations; instead, pathways representing functions critical for microbial survival and communication were activated as well. According to enzymatic analyses, low pyrene levels promoted carbohydrate metabolism by sediment microorganisms, whereas high levels had an inhibitory effect. An examination of electron transport enzymes revealed that intracellular electron transfer was facilitated by both low and high concentrations. However, high levels impeded enzymes associated with outer membrane electron transfer, hindering electron movement from intracellular to extracellular electron acceptors and thus negatively affecting the electrical output of MES. Our study provides crucial theoretical insight and mechanistic understanding for addressing the challenges that may be encountered when MES are used to treat pyrene-contaminated sediment near industrial sites.

Characterization and Source Analysis of Heavy Metal(loid)s Pollution in Soil of an Industrial Park in Kunming, China

This study investigated the characteristics and sources of heavy metal(loid) pollution in the soil of a key industrial park in Kunming, China. In total, 60 soil samples (40 from agricultural land and 20 from construction land) were collected from and around the park. The soil pH and contents of Arsenic (As), lead (Pb), copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg), nickel (Ni), and chromium (Cr) were measured. The contents of the eight heavy metal(loid)s were analyzed using the background values of heavy metal(loid)s in the Kunming soil. The pollution load, geoaccumulation, and Nemero Comprehensive Pollution Indices were used for environmental risk evaluation. Cluster and principal component analyses were used to resolve heavy metal(loid) sources. Cd was enriched in construction and agricultural soils. As, Hg, Cd, Pb, Cu, and Zn exhibited large spatial differentiation and were significantly affected by the external environment. A regional pollution load index of 3.02 indicated overall heavy pollution. The pollution load index for each heavy metal(loid) indicated light pollution. The geoaccumulation index indicated relatively severe As, Cd, Cu, Pb, and Zn pollution. The Nemero Composite Pollution Index value showed that the study area was heavily polluted, with construction land being mildly polluted by Cd, and agricultural land being moderately polluted. The results of the spatial distribution show that there were high levels of contamination in the center. Correlation and principal component analyses showed that the pollution sources of the eight heavy metal(loid)s varied. Hg, Cd, and Pb originate primarily from industrial and agricultural pollution. Traffic sources significantly impacted Cu, Pb, Cd, and Cr. Natural sources are the main sources of Cr, Ni, and Cd. Ni is also affected by industrial sources, whereas Zn and Cu are affected by agricultural pollution. The influences of As, Cd, and Pb on the surface soil in the study area were more serious. Cd is more widely polluted and should be a priority in controlling soil heavy metal(loid)s.

Microbiological risk assessment of Bacillus cereus in popular hot dishes eaten by plant-based diet consumers in France

There is a current trend towards plant-based diets in Western countries. Since changes in the diet imply possible changes in exposure to foodborne pathogens, there is an increasing need to assess the microbiological risks associated with these diets. This study aims to assess microbiological risks for French adults associated with Bacillus cereus group III and group IV in hot, homemade cereal- and lentil-based dishes. A probabilistic retail-to-fork risk assessment model was developed considering cooking, cooling at ambient temperature, and storage under chilled conditions. Data came from a representative national survey, public database and literature. The model was developed in R, and uncertainty and variability were separated using second-order Monte Carlo simulations. Not all consumers have the same storage and cooling practices, so the results were expressed by probabilistic distributions built by specific storage time. The mean concentration of Bacillus cereus in portions at the time of consumption after 72 h of storage was 1.2 log CFU.g−1 for cereal-based dishes and 3.4 log CFU.g−1 for lentil-based dishes. After 72 h of storage under chilled conditions, the risk per portion, defined as the probability of contamination over 5 log CFU.g−1, was 0 (95 % CI: 0 - 0) for cereal-based dishes and 7.95 × 10−4 (95 % CI: 5.55 × 10−4 - 1.12 × 10−3) for lentils-based dishes. However, if cooling time at room temperature reached 24 h, the risk for cereal- and lentil-based dishes increased to 2.39 × 10−3 (95 % CI: 1.15 × 10−3 - 4.90 × 10−3) and 4.66 × 10−1 (95 % CI: 3.16 × 10−1 - 6.07 × 10−1), respectively. The sensitivity analysis indicated that the initial prevalence and level of contamination were key factors in limiting the risk, ranking before cooling time or refrigeration conditions. Besides, the scenario analysis revealed an influence of consumer behaviour regarding cooling and storage time on the risk per portion. The environmental trend towards plant-forward diets, combined with the emerging no-food waste and batch cooking practices in France, will likely favour new consumption patterns and increase the risk associated with Bacillus cereus. Our model will help quantify this extra burden.

Multi-Biomarkers' Responses in Gills of Oreochromis niloticus Exposed to Glyphosate and Polyethylene Microplastic, Isolated and in Mixture.

Microplastics (MPs) and glyphosate-based herbicides (GBH) are among the most common contaminants in aquatic environments. In Brazilian rivers, both contaminants were found in elevated levels, leading to a high probability of their association, which can alter their individual effects and potentially intensify their toxicity. This study evaluated the isolated and combined effects of polyethylene microplastics (PE-MPs) and GBH on Oreochromis niloticus using multi-biomarkers of toxicity. The fish were subjected to a 96-h exposure period, with concentrations set based either isolated, PE-MPs group (5 mg L-1), GBH group (5 mg L-1), or in a group of associated contaminants (GAC), PE-MP + GBH (5 mg L-1 + 5 mg L-1). Toxicity effects were evaluated using biochemical, cytogenetic, hematological, and histopathological biomarkers. We observed change in erythrocyte parameters leading to macrocytic normochromic anemia in GAC. Leukocyte parameters indicate a nonspecific immunosuppression caused by the exposure of associated contaminants, besides the attempts to repair damage caused by PE-MPs. Histopathological markers indicate damage to tissues exposed to contaminants. Besides, there were morphophysiological adjustments on gills, with proliferation and hypertrophy of mitochondria-rich cells on GBH and GAC, besides epithelium ruptures, which were mostly present in the exposed groups. Therefore, this study indicates that PE-MPs and GBHs present toxic effects in O. niloticus with the used concentrations, intensified by the association of contaminants. Thus, multi-biomarkers were useful key to verify toxicity, providing data to the investigation of high levels of contaminant's mixture toxicity present in aquatic environments.

Use of lichens as bioindicators of contamination by agrochemicals and metals.

The presence or absence of lichens serves as an indicator of the condition of an ecosystem and the degree to which it is contaminated by various agents, such as agrochemicals and metals. Evaluating the use of lichens as bioindicators of agrochemical contamination could provide a more comprehensive perspective of current contamination levels. Monitoring was conducted over a 4-month period in two study areas: one was a well-conserved area contaminated by metals, and the other was an area surrounded by agricultural crops contaminated by agrochemicals. Data on the presence and abundance of lichens in each study area were recorded at 10 monitoring points, a procedure that was repeated 16 times (every 15days), and concentrations of heavy metals and "organophosphate" agrochemicals in the lichens collected were measured by means of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-OES) and Gas Chromatography (GC), respectively. Generalized linear mixed models were used to assess abundance and richness, while general linear mixed models were used to attain Shannon diversity and Simpson dominance indices. Moreover, a multivariate analysis was performed in order to compare the lichen communities in both areas. The results indicated differences between the area contaminated by metals and that contaminated by agrochemicals in terms of abundance and Simpson's dominance index, while no differences were found in the case of the richness and diversity models. The PERMANOVA analysis additionally showed differences between the lichen communities in the two areas. The results also demonstrated that Canoparmelia caroliniana bioaccumulated metals in both areas. The levels of barium, cadmium, and sodium were higher in the area contaminated by metals, while concentrations of chromium and copper were higher in the area contaminated by agrochemicals. Finally, the concentrations of agrochemicals were higher in the area contaminated by agrochemicals and included toxic substances such as Methylparathion and Parathion, which are prohibited in Ecuador. In conclusion, this research underscores the importance of lichens as precise indicators of environmental health and contamination by agrochemicals and metals.

Times series record of water quality analysis during flood time in Cauvery River basin, Tamil Nadu, India

We determine the spatial and temporal changes in the physicochemical and nutritional parameters of water quality in the Cauvery River basin. We also analyze the effects of anthropogenic and natural factors on the physicochemical and nutritional parameters. The river water samples were collected over a time series record of 6-h intervals for 6 days during and after flooding time. The combination of physicochemical and nutritional parameters generated a large dataset, which was processed using statistical analysis. In addition, statistical analysis was used to calculate the correlation coefficients and plot the regression equations relating various parameters to electrical conductivity (EC). The resulting average values of pH, EC, and total dissolved solids (TDS) showed significant differences in the time series record of the study period (i.e., pH = 8.24, EC = 220 S/m, and TDS = 157.1 mg/L). The values of the following nutritional parameters in floodwater were also determined: orthophosphate = 0.13 mg/L, phosphate = 0.1 mg/L, nitrite = 2.11 mg/L, nitrate = 0.79 mg/L, and ammonia = 4.47 mg/L. Our findings indicates that flooding can deteriorate the groundwater quality, resulting in a decrease in water quality and an increase in contamination levels, which can have detrimental effects on both the environment and human health. This information is crucial to decision making in flood risk management, water resource planning, and conservation efforts to protect both human and ecological systems.

Geospatial insights into groundwater contamination from urban and industrial effluents in Faisalabad

Groundwater remains the most dependable resource for various essential uses such as drinking, cleansing, agricultural irrigation, and industrial applications. In urban areas, the dependency on groundwater to meet water demands is significant. However, this resource faces threats from overuse and poor management, leading to a degradation in quality primarily due to the unchecked release of industrial and household wastes. The escalation of industrial activities and rapid urban growth have amplified the volume of wastewater, adversely affecting the purity of freshwater sources within aquifers. This investigation focuses on evaluating the impact of industrial and urban effluents on groundwater quality in the city of Faisalabad. The main contributors to groundwater pollution include the indiscriminate disposal of industrial and urban effluents through unlined drains and the extensive application of chemical agents in agriculture, such as fertilizers, and pesticides. To understand the physiochemical properties of both, drain and groundwater, samples were collected at various distances 50 m, 100 m, and 150 m from drain outlets. This study utilized Geographic Information Systems (GIS) to accurately map and analyze the distribution and impact of contaminants. Parameters such as pH, electrical conductivity (EC), total dissolved solids (TDS), total hardness, bicarbonates, calcium and magnesium hardness, and chloride levels were examined. The findings indicated that contaminant levels were highest in drain water and increased in concentration the closer they were to the drainage sources, with the exception of pH levels. All samples exceeded the World Health Organization's (WHO) safe limits, deeming them unfit for use. This finding indicates widespread contamination, posing significant public health risks and highlighting the urgent need for improved waste management and water treatment practices in Faisalabad. It underscores the critical importance of implementing effective pollution control measures to safeguard public health and ensure water security in the region. However, a notable correlation was observed between the concentration of pollutants in drain water and key indicators such as EC, TDS, total hardness, and magnesium hardness, highlighting their role in deteriorating aquifer water quality. Moreover, groundwater samples collected 50 m from drains exhibited the highest pollutant concentrations compared to those taken further away, at 100 m and 150 m distances.

Level of Contamination and Alteration of Cuttlefish Fished and Processed in Companies in Côte d’Ivoire

This study was carried out from 2019 to 2021. Its aim was to assess the quality of cuttlefish intended for local and international markets in a company processing fishery products in Côte d'Ivoire. The biochemical analyses (Total Volatile Basic Nitrogen (TVBN)) were based on the distillation method of an extract deproteinised by perchloric acid (HClO<sub>4</sub>). Microbiological analyses (total aerobic mesophilic flora (TAMF), staphylococci (SPP), anaerobic sulphite-reducing bacteria (RAS), faecal coliforms (FC) and salmonella) involved isolation and identification techniques. The various analyses carried out by the National Laboratory for Support to Agricultural Development (LANADA) made it possible to assess the median contamination values and satisfaction percentages (TAMF, FC, SPP), which are respectively 2.2.10<sup>4</sup> CFU/g with 94%; less than 10 CFU/g with 94%; less than 100 CFU/g with 100%. RSA and salmonella were absent in all the products analysed. The temperature of the cuttlefish was high just after processing. The maximum temperature value (26.4°C) was obtained after processing, while the minimum temperature value (1.6°C) was recorded during storage in a positive cold room. However, it is essential to improve manufacturing practices and preservation methods in order to avoid poisoning the population. These data should also encourage fishermen to practise good preservation methods.

Ecotoxicity of Tar from Coffee Grounds and Pine Pellet Gasification Process

This study determined the toxicity of the condensates produced during the gasification of two waste types. Coffee grounds, pine pellets, and a mixture of both substrates at a ratio of 1:1 were used in the study. Two microbiotests were applied for soil plants and aquatic macrophytes, and quantitative analysis of the soil microbiome for primary taxonomic groups of microorganisms was conducted. Three contamination rates were used in the Phytotoxkit test and the microbiological tests, 100, 1000, and 10,000 mg·kg−1 d.m. of soil, while in the aquatic organism studies, successive two-fold serial dilutions of condensates were used. The presence of liquid waste from the gasification process adversely affected the germination and development of terrestrial plants and the vegetative growth of aquatic plants. The condensate components modified the composition of the soil microbiome, adversely affecting soil fertility. The negative impact increased with increasing levels of contamination and primarily depended on the type of substrate from which the gasification process produced the liquid waste.

Open dumping site as a point source of microplastics and plastic additives: A case study in Thailand

Microplastics (MPs) and plastic additive chemicals are emerging pollutants of great concerns around the world. Open dumping sites can be important sources of those pollutants in emerging countries, but little is known about their occurrence, distribution, transport pathway, and remediation approach. This study aimed to obtain the comprehensive dataset on plastic pollution in an open dumping site in Thailand, including (1) the polymer types and organic/inorganic plastic additives in plastic garbage, (2) horizontal distribution of MPs and plastic additives in the surface soil, (3) the effects of soil-capping treatment, and (4) the vertical transport. First, thirty-two plastic garbage collected from the dumping site were analyzed, and a total of 40 organic chemicals (mean: 1400,000 ng/g dw) and 7 heavy metals (mean: 2,030,000 ng/g dw) were identified. The burdens stored in the dumping site were estimated to reach to 3.3–18 tons for organic additives and 4.9–26 tons for heavy metals. In the surface soil analysis, 13 types of polymers in MPs, 20 elements, and 37 organic plastic additives were detected. The pollution levels were significantly higher near the dumping site than at control sites, indicating that the open dumping site is a point source of MPs and plastic additives. Interestingly, a significantly positive correlation was found between the concentrations of MPs and organic additives in soil. This suggests that MPs act as carriers of plastic-derived chemicals. Soil-capping treatment (including removal of some trash) drastically mitigated the contaminant levels in the surface soil, indicating this treatment is one of the effective approaches to control the horizontal distribution of MPs and plastic additives. However, soil core analyzes implied that the vertical transport is still continued even after soil-capping treatment. Our findings provided the comprehensive dataset to support for understanding plastic pollution in the open dumping site.

A Baseline Assessment of Contamination in the Sacramento Deep Water Ship Channel

The Sacramento Deep Water Ship Channel (SDWSC) in the San Francisco Estuary, which is an active commercial port, is critical habitat for pelagic fish species including delta smelt (Hypomesus transpacificus), longfin smelt (Spirinchus thaleichthys), and Sacramento perch (Archoplites interruptus). Pelagic organism decline has been attributed to covarying factors such as manipulation of habitat, introduction of invasive species, decrease in food production, and contaminant exposure. Quantification of bioavailable toxicant loads in the SDWSC is limited despite previous surveys that have detected elevated contaminant concentrations in the sediments. Therefore, the focus of the present study was to characterize the bioavailability of the contaminants in the SDWSC from six sites along the channel. At each site, organochlorine pesticides (OCP), pyrethroid insecticides, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were quantified in sediment, zooplankton, and suspended solids. In addition, Tenax extraction was used to measure the bioaccessible fraction of sediment-associated contaminants freely dissolved in the water. Bioaccessible contaminants in the sediment provided an uptake route for these stressors into invertebrates and fish with bioaccessible OCPs being found at all sites, particularly 4,4’-dichlorodiphenyldichloroethylene (DDE). Bifenthrin was the only pyrethroid to be detected in the chosen matrices and it was found at concentrations below levels of concern. Bioaccessible PAHs were found at all sites, with highest detections for phenanthrene and pyrene. No PCBs were detected in sediments, but were detected in both suspended solids and zooplankton. Contaminant concentrations overall were significantly higher in suspended solids, followed by zooplankton and sediments. The highest sediment concentrations of DDE, fluoranthene, pyrene, and dibenzo[a,h]anthracene exceeded sediment quality benchmarks which suggested potential risk to sediment-dwelling species. Finally, elevated contaminant levels were found in both suspended solids and zooplankton, suggesting additional risk to pelagic species in the SDWSC.

Proposal of database of radiological characterization for decommissioning nuclear power plants

AbstractIn Korea, Kori Unit 1 was permanently closed in 2017 and scheduled for decommissioning. Kori Unit 1 is currently scheduled to undergo system decontamination and to be decommissioned by December 2038. Measures to properly control and remove radiological hazards must be established to go through decommissioning a nuclear power plant (NPP). Radiological characterization must precede NPP decommissioning. Radiological characterization generates a lot of data during this process. The consistency of radiological characterization data is important for systematically decommissioning NPPs. However, the data generated from radiological characterization may not be systematically managed because a database of radiological characterizations for Kori Unit 1 has not been properly established. Therefore, this study has proposed a database to be filled during radiological characterization in terms of occupational radiation exposure of personnel and decommissioning waste safety using key performance indicators presented by the International Atomic Energy Agency. From the perspective of occupational exposure, databases have been proposed for operational history investigations, decommissioning source term calculations, and investigation of the level of radiological contamination. From the perspective of the safety of decommissioning waste, databases were proposed for operational history investigation, decommissioning source term calculation, investigation of the level of radiological contamination, and investigation of radiological characteristics of decommissioning waste.

WATER QUALITY PREDICTION USING MACHINE LEARNING TECHNIQUE

The quality of water is a critical parameter that affects human health, aquatic ecosystems, and environmental sustainability. The prediction of water quality using machine learning techniques has emerged as a promising solution for early detection and management of water pollution. This project focuses on developing a predictive model that leverages historical water quality data to forecast future water quality indices. Various machine learning algorithms, including regression and classification techniques, will be employed to analyze parameters such as pH, turbidity, dissolved oxygen, and contaminant levels. By training the model on a comprehensive dataset, the system aims to provide accurate and timely predictions, enabling proactive measures to be taken to ensure safe water supplies. The implementation of this model can significantly aid regulatory bodies and water management authorities in monitoring and maintaining water quality standards, ultimately contributing to public health and environmental conservation.