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This study aimed to investigate the bioaccumulation of cadmium from natural feed substrate and substrate enriched with CdCl 2 and CdO by the common green bottle fly, Lucilia sericata (Diptera: Calliphoridae). Cadmium was determined in all developmental stages (larvae, adults, and puparial cases) of L. sericata, and its accumulation was positively correlated with concentrations in insect diets. Higher bioaccumulation factors of Cd were found in larvae and adults fed with naturally contaminated liver tissues (1.3-3.9) than those fed with liver enriched with cadmium in the form of inorganic compounds (0.4-0.9). The effect of cadmium dose on insect development was also studied. Cadmium exposure caused disorders in the metabolism of Zn, Cu, and Mn, and the effect depended on its form present in the diet. Insects must be tested for the presence of heavy metals to demonstrate their safety and quality as novel feed and food products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Seabirds are particularly susceptible to potentially toxic elements (PTEs) due to the tendency of biomagnification of some elements, thus serving as potential bioindicators for assessing environmental health. In this study, we analyzed As, Cd, Cu and Zn concentrations in liver samples from nine seabird species (51 specimens) collected along the Southwestern Atlantic Ocean. Results revealed substantial variations in PTE concentrations among species, with taxonomic orders influencing accumulation patterns. The observed PTE concentrations in seabirds suggest potential trends in bioaccumulation, influenced by species-specific behaviors and diets. For instance, As ranged from 0.47 mg kg -1 in Nannopterum brasilianus to 70.25 mg kg -1 in Thalassarche melanophris, while Cd ranged from 0.01 mg kg -1 in N. brasilianus to 232.73 mg kg -1 in Spheniscus magellanicus. Generalized Linear Model (GLM) results identified body length and species as the main factors influencing PTE concentrations for most elements. Spearman correlation analysis revealed a strong positive correlation between Cd and Cu (ρ = 0.68), Cd and Zn (ρ = 0.67) and between Zn and Cu (ρ = 0.56), suggesting that seabirds with higher Cd levels also tend to have higher Cu and Zn concentrations. Multivariate statistical analysis demonstrated distinct PTE compositions among bird groups. Although significant variations in total concentrations of elements like Zn and Cu were observed among species, the relative contributions of each element to the overall load in the organism showed a convergence in proportions. This underscores the need for further research on homeostatic processes and the potential impacts of environmental PTEs on seabird health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Potentially toxic metal contamination in marine environments poses significant risks to both ecosystems and human health. Mussels, as filter feeders, are particularly susceptible to accumulating these contaminants, making their safety a critical concern. This study aims to investigate the correlation between potentially toxic metal concentrations in attachment ropes and mussel soft tissues in an aquaculture setting. We analyzed the levels of Hg, Cu, Zn, As, Cd, Pb, and Cr in both substrates and assessed the health risks using the Target Hazard Quotient (THQ) method. Results show that while most potentially toxic metals (Hg, Cu, Zn, Pb, Cr) in mussels present low health risks with THQ values below 1, As and Cd pose significant risks, with As showing a THQ value significantly above 1. No significant correlations were found between the potentially toxic metal concentrations in ropes and mussel tissues, indicating other environmental factors influence metal bioaccumulation in mussels. These findings underscore the necessity for comprehensive monitoring and targeted mitigation strategies to reduce potentially toxic metal contamination in aquaculture environments, ensuring the safety and sustainability of mussel production., Competing Interests: Declarations. Conflict of interest: The authors declare that they have no conflict of interest., (© 2025. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Selenium (Se) occurs in natural surface waters as a variety of inorganic and organic chemical species, typically dominated by the oxyanions selenate and selenite. Organoselenium species, although hypothesized to be more bioavailable than oxyanions, have rarely been identified or quantified in natural waters and little is known about their fate or bioaccumulative potential. We studied spatial patterns of bioaccumulation in relation to aqueous Se speciation over 5 years at more than 100 locations near coal mine operations in southeast British Columbia, Canada. We used a sequential approach to fitting bioaccumulation model coefficients, first using sites with no detectable organic Se species (< 0.01 µg L-1) to describe the bioaccumulation of selenate and selenite, then applying those relationships to the remaining sites to infer the bioavailability of detectable organoselenium species. Our analysis indicated that the methylated species methylseleninic acid was the most bioaccumulative form, followed by dimethylselenoxide. Organoselenium species were associated primarily with mine sedimentation ponds and are presumed to be products of Se metabolism by algae and bacteria. Highly bioavailable organoselenium species exported from the ponds appear to be responsible for enhanced Se bioaccumulation in biota in downstream lotic reaches, with this influence diminishing with distance from ponds as concentrations decline. Our findings indicate that managing biological productivity in mine sedimentation ponds could help manage Se risk in the receiving environment., (© The Author(s) 2025. Published by Oxford University Press on behalf of the Society of Environmental Toxicology and Chemistry. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

This study examines the kinetics of absorption, distribution and accumulation of arsenite (As III) in the freshwater gastropod Pomacea canaliculata using a short-lived tracer ( 76 As III). The toxicokinetic model indicate that the gills play a crucial role in the As III uptake, with uptake rates significantly exceeding those of release back into the aquatic environment. The movement of As III from the gills to the hemolymph has low exchange rate. The hemolymph acts as a convective transport medium, facilitating the distribution of As III to various organs of accumulation and elimination within the snail. The majority of As III detected in the hemolymph is directed toward the kidney, stomach, coiled gut and digestive gland. Following feeding, the maximum As inventory (90 %) was reached at 24 h, after which an elimination phase with approximately 4 % between 24 and 96 h According to our toxicokinetic model, feces is the primary route of elimination would be. By 96 h, As III is localized in the digestive gland (70 %) and visceral mass (6 %). Furthermore, tissue accumulation shows a linear correlation with increasing As III concentrations in the surrounding water. By integrating 76 As radiotracer assays with physiological information, we gain valuable insights in the toxicokinetic of both As III and As V. We hypothesize that biotransformation may occur between these two inorganics As forms at the tissue level., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Israel A. Vega reports financial support was provided by Fund for Scientific and Technological Research. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2025. Published by Elsevier B.V. All rights reserved.)

Per- and polyfluoroalkyl substances (PFAS), often termed "forever chemicals," are a diverse group of persistent fluorinated compounds, including the well-known perfluorooctanesulfonic acid (PFOS), which has been identified as lethal to bee larvae. However, the risk of PFAS exposure through pollen, a bee's primary food source, has not been thoroughly investigated. In controlled greenhouse experiments, Cannabis sativa L. (hemp) plants were cultivated in soil contaminated with eight PFAS compounds. Phytoremediation potential was assessed by measuring bioconcentration factors (BCF) in both the total above-ground biomass and pollen. The study found that BCF for total PFAS in hemp pollen was significant (>20.8), with over 45% of the total PFAS uptake of around 3248 μg/kg concentrated in the pollen. Based on these figures, the estimated daily intake (EDI) of PFOS for western honeybees (Apis mellifera) was found to be about 124.5 μg/kg body weight per day. These findings underscore a critical global threat to pollinator health, with significant implications for agriculture and biodiversity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier Ltd. All rights reserved.)

Arsenic (As) concentrations were measured in the muscle and liver of the speckled guitarfish Pseudobatos glaucostigmus and its main prey Penaeus californiensis, in Santa Rosalia, western Gulf of California, to determine bioaccumulation and biomagnification. Higher mean wet weight (w.w.) values were found in muscle tissue (9.87 μg g -1 ) compared to liver tissue (5.32 μg g -1 ); however, the highest concentrations were found in the liver (48.05 μg g -1 ). All samples showed As concentrations above the maximum permissible limit for human consumption. The highest concentrations in mature females (muscle: 6.93 μg g -1 ; liver: 14.5 μg g -1 ) concerning pregnant females (muscle: 5.01 μg g -1 ; liver: 8.46 μg g -1 ) may indicate a maternal transfer of As from mothers to their embryos. Arsenic bioaccumulates in the liver, which was evident from the positive correlation between total length and As concentration. Arsenic levels in Penaeus californiensis showed biomagnification from prey to predator for both tissues., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The rapid melting of the Arctic cryosphere due to climate change will result in significant freshwater input into Arctic marine ecosystems. This might also cause the release of legacy mercury (Hg) stored in the cryosphere, increasing Hg concentration and its subsequent effects on the marine biota. However, there is scarce knowledge on the concentration of Hg in the lower trophic level organisms at the base of the Arctic pelagic food web. This is particularly important since these organisms modulate the transfer of Hg to higher trophic levels, including fish and marine mammals. We quantified the total Hg (THg) concentration in two plankton size classes (>200 and 50-200 μm) in coastal waters along the east Greenland coast and investigated the potential assimilation efficiency of both inorganic Hg (IHg) and methyl Hg (MeHg) in mesozooplankton and their faecal pellets in experimental incubations. The concentration of THg in plankton ranged from 12 to 109 ng (g dw) -1 without clear trends between geographic locations or between fjords and coastal areas. Also, the concentrations did not vary between the different plankton size fractions. MeHg concentrations were lower in the mesozooplankton faecal pellets than IHg, which may be due to the higher assimilation of MeHg than IHg in mesozooplankton tissue. Our results confirm that Arctic zooplankton assimilates MeHg more efficiently than IHg and may contribute significantly to the partitioning and cycling of different Hg types in Arctic marine ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Soil is an important sink for microplastics (MPs) and pesticides. MPs can act as carriers for pesticides, thus induce direct and indirect effects on soil organisms. Fluindapyr (FIP), a novel succinate dehydrogenase inhibitors fungicides (SDHIs), may pose a serious threat to earthworms. However, few studies have evaluated the effects of joint exposure to MPs and FIP. Here, earthworms (Eisenia fetida) were jointly exposed to PMMA (polymethylmethacrylate) and PS (polystyrene) MPs of different sizes (0.1, 1 and 10 μm) along with FIP for 28-day to investigate the toxic effects of single and joint exposure of FIP and MPs on earthworms. The results showed that joint exposure to 0.1 and 1 μm MP promoted the accumulation of FIP in earthworms at the beginning of the experiment compared to the sole group, but the elimination of FIP from earthworms accelerated after 14 d. In addition, the joint exposure caused more serious damages to the epidermis and intestine of earthworms and increased the severity of oxidative stress. The effects of joint exposure to FIP and MPs depended on the size of the MPs, and the strongest effects were observed in the treatment with the smallest size. The 16S rRNA sequencing results showed that the joint exposure to MPs and FIP didn't cause gut microbiota dysbiosis. However, the sole 0.1 μm PS significantly altered the community diversity and richness of earthworm gut bacteria, and the relative abundance of Proteobacteria, Actinobacteria and Firmicutes was significantly changed. The obtained results inferred that MPs could influence environmental and toxicological behaviors of FIP and may provide data support for the risk assessments of MPs and FIP on soil ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Iron oxide nanoparticles (IONPs) are prominent in nanomedicine, cosmetics, and environmental applications. However, their increasing production, use, and release into the environment raises concerns about their potential risks to aquatic life and human health. This study aimed to evaluate the bioaccumulation, as concentration of small, medium and large iron aggregates in the digestive tubules, histopathological changes, and inflammatory responses in the freshwater snail Biomphalaria glabrata following chronic exposure to gluconic-acid functionalized IONPs (GLA-IONPs) compared to their dissolved counterpart (FeCl 3 ). The snails were exposed to both iron forms (1.0, 2.5, 6.25, and 15.62 mg L⁻ 1 ) for 28 days. The qualitative and quantitative histopathological assessment of digestive glands was conducted, followed by an analysis of histopathological indices. Both forms of iron accumulated in the digestive gland and induced inflammatory responses, vacuolization, necrosis of secretory cells, and atrophy of the digestive tubules. While FeCl 3 showed greater accumulation in the digestive tubules compared to GLA-IONPs (small: 1.92-6.55-fold; medium: 5.84 to 4.6-fold; large aggregates: 26.5 to 8.3-fold), the IONPs caused more severe histopathological changes, including increased atrophy of digestive tubules (1.0 mg L⁻ 1 : 1.94 -fold) and hemocyte infiltration (1.0 mg L⁻ 1 : 1.41-fold; 15.62 mg L⁻ 1 : 1.33-fold). Thus, this study indicates differential bioaccumulation between GLA-IONPs and dissolved Fe, with GLA-IONPs inducing more pronounced toxicity and histopathological damage in the digestive gland of B. glabrata, leading to a loss of digestive functions and confirming their potential risk to aquatic biodiversity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Ltd. All rights reserved.)

Significant variation in mercury (Hg) bioaccumulation is observed across the diversity of freshwater ecosystems in North America. While there is support for the major drivers of Hg bioaccumulation, the relative influence of different external factors can vary widely among waterbodies, which makes predicting Hg risk across large spatial scales particularly challenging. We modeled Hg bioaccumulation by coupling Hg concentrations in more than 21,000 dragonflies collected across the United States from 2008 to 2021 with a suite of chemical (e.g., dissolved organic carbon (DOC), pH, sulfate) and landscape (e.g., soil characteristics, land cover) variables representing external drivers of Hg methylation, transport, and uptake. Model predictions explained 85% of the variation in dragonfly Hg concentrations across the United States. Certain predictor variables were more important than others (e.g., DOC, pH, and percent wetland), and they varied among waterbodies. Variation in Hg bioaccumulation was explained by including habitat and ecosystem type in a hierarchical modeling framework, which confirms the context-dependency of external factors in explaining Hg bioaccumulation across disparate freshwater ecosystems. This continent-scale model provides valuable insights into the processes underlying landscape-scale patterns in Hg exposure risk and demonstrates that drivers of Hg methylation and bioaccumulation are habitat- and ecosystem-dependent.

Aquatic toxicology, as a result of industrial and agrieqcultural effluences, has become a global concern impacting not only the well-being of aquatic organisms but human health as well. The current study evaluated the impact of four toxic trace elements (TTEs) Cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) in three organs (liver, gills, and muscles) of five fish species viz, Rita rita, Sperata sarwari, Wallago attu, Mastacembelus armatus, and Cirrhinus mrigala collected from right and left banks of Punjnad headworks during winter, spring, and summer. We investigated the accumulation (mg/kg) of these TTEs in fish in addition to the human health risk assessment. The obtained results showed that W. attu accumulated significantly more TTEs (p < 0.00) as compared to other fish. Among seasons, summer had significantly more (p < 0.00) accumulation of TTEs than other seasons. Lead (Pb) accumulation was highest across TTEs in fish liver as compared to gills and muscles. The right bank showed higher accumulation (p < 0.00) of all TTEs in all fish species compared to the left bank. The human health risk assessment showed that Cd and Pb had higher exposure levels than Cu and Ni. Furthermore, the THQ was in the order of Cd > Pb > Ni > Cu. All fish species had THQ 1 for Cd and Pb and TTHQ > 1 for all fish. MPI index showed moderate to high levels of TTE contamination in all fish species. The study concluded that the right bank has higher metal accumulation than the left bank. However, fish consumption from both study sites was unsafe for human consumption. Further studies are required to evaluate the contamination of other trace elements in the aquatic ecosystem of the current site. This study will be useful for policymakers and the water department to take necessary counteractions to reduce the impact of TTEs at the study site., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2025 Naz et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Nano(micro)plastics (NMPs) and agrochemicals are ubiquitous pollutants. The small size and physicochemical properties of NMPs make them potential carriers for pollutants, affecting their bioavailability and impact on living organisms. However, little is known about their interactions in terrestrial ecosystems. This study investigates the adsorption of Fenpropathrin (FPP) onto two different sizes of polystyrene NMPs and examines their impacts on an insect model, silkworm Bombyx mori. We analyzed the systemic effects of acute exposure to NMPs and FPP, individually and combined, at organismal, tissue, cellular, and gut microbiome levels., Results: Our results showed that NMPs can adsorb FPP, with smaller particles having higher adsorption capacity, leading to size-dependent increases in the bioaccumulation and toxicity of FPP. These effects led to higher mortality, reduced body weight, delayed development, and decreased cocoon production in silkworms. Additionally, the pollutants caused physical and oxidative damage to the midgut and altered gene expression related to juvenile hormone (JH) and silk protein synthesis. The gut microbiome analysis revealed significant changes and reduced abundance of potentially beneficial bacteria. Thus, the aggravated toxicity induced by NMPs was size-dependent, with smaller particles (NPs) having a greater impact., Conclusions: This study demonstrates the role of NMPs as carriers for contaminants, increasing their bioavailability and toxicity in terrestrial ecosystems. These findings have significant implications for ecosystem health and biodiversity., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Paddy soil is recognized as a hotspot for mercury (Hg) transformation. Soil acid-base property (expressed as pH) plays a crucial role in Hg methylation and accumulation in paddy systems. However, it is challenging to study this process in soils with varying pH values due to the rarity of a single soil type spanning a wide pH range. Purple paddy soil, vital for rice cultivation in southwestern China, occurs naturally in three types based on pH: acidic, neutral, and calcareous. This variation makes purple paddy soil an ideal subject for these studies. Thus, this study investigated Hg transformation and bioaccumulation across these three purple soil types. The results showed that during the rice growing seasons, both methylmercury (MeHg) concentration and methylation potential were higher in acidic purple paddy soil than in neutral and calcareous types. In addition, total mercury (THg) and MeHg concentrations in plant tissues grown in acidic purple paddy soil were significantly higher than in other two purple soil types. These results suggest that acidic purple paddy soil was conducive to Hg methylation and accumulation in rice plants. Given that soil acidification is becoming a serious global issue, the findings could offer fundamental data on the potential risk of Hg exposure due to soil acidification., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Accurate prediction of bioaccumulation parameters is essential for assessing exposure, hazards, and risks of chemicals. However, the majority of prediction models on bioaccumulation parameters are individual models based on a single algorithm and lack model interpretation, resulting in unsatisfactory prediction accuracy due to inherent constraints of the algorithm and weak interpretability. Ensemble learning (EL) that combine multiple algorithms, coupled with SHapley Additive exPlanation (SHAP) method, may overcome the limitations. Herein, EL models were constructed for three bioaccumulation parameters using datasets covering 2496 chemicals. The EL models demonstrated superior prediction accuracy compared to both individual models developed in this study and those from previous research, achieving a coefficient of determination of up to 0.861 on the validation sets. Applicability domains were characterized using a structure-activity landscape-based (abbreviated as AD SAL ) methodology. The optimal EL models, together with the AD SAL , were successfully used to predict bioaccumulation parameters for 4374 chemicals included in the Inventory of Existing Chemical Substances of China. Model interpretation using the SHAP method offered insight into key features influencing bioaccumulation potential, including hydrophobicity, water solubility, polarizability, ionization potential, weight, and volume of molecules. Overall, the study provides data and models to support the sound management and risk assessment of chemicals., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microcystins-common hepatotoxins produced by cyanobacteria-have been detected in a wide range of organisms, though research examining the trophic transfer of microcystins and whether microcystins bioaccumulate or biomagnify in food webs has generated contradictory results. Here, we explored the trophic transfer of microcystins from the herbivorous water flea, Daphnia pulex, to the predatory larvae of a damselfly, Enallagma sp. We tested the hypotheses that microcystins transfer from the tissue of herbivorus zooplankton to that of predatory invertebrates and that these toxins biomagnify across trophic levels. We also assessed the relative contribution of toxin transfer from the gut and tissue of Daphnia pulex to Enallagma sp. We found that microcystins are effectively sequestered in the tissue of Daphnia pulex, and that these sequestered toxins are then transferred to the tissue of Enallagma sp. The contribution of gut contents to toxin transfer was negligible. Contrary to the pattern predicted by biomagnification, we found that the concentration of microcystins decreased with increasing trophic levels. Our results support the hypothesis that microcystins can be transferred trophically, but do not support the hypothesis that microcystins biomagnify from lower to higher trophic levels. Conversly, we observe biodilution in this system. These results have consequences for the impact of microcystins across trophic levels in a changing world with increasing intensity and duration of harmful algal blooms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

In this work, bioaccessibility tests for rare earth elements (REEs), Th, and U in marine sediment were carried out, in addition to complementary tests for cytotoxicity and bioaccumulation for the elements La, Ce, Eu, and Gd. The evaluation of human health risk through dermal absorption and oral ingestion was performed using the hazard quotient (HQ). According to the gastric digestion simulation (SBET), it was observed that the elements Ce and Nd exhibited higher absorption capacities in the human body (> 2 µg g -1 ). La and Sc presented intermediate concentrations (close to 1 µg g -1 ), while the remaining elements displayed concentrations below 0.5 µg g -1 . In the gastrointestinal digestion extraction stage (PBET), all the elements maintained a similar absorption capacity to that observed in SBET, except for the absorption of Y which increased. The results of the bioaccumulation test conducted with fibroblast cells (L929) indicated that La and Eu had a 25% probability of intracellular accumulation. The cell viability test, with exposure to a standard REEs, Th, and U solution in 2% v v -1 HNO 3 medium (until 100 μg mL -1 ) and an aqueous solution of La 2 O 3 , Gd(NO 3 ) 3 , Ce(NO 3 ) 3 , and Eu 2 O 3 (until 1000 μg mL -1 ), did not demonstrate cytotoxic effects on fibroblast cells. Considering the ingestion hazard quotient (HQ ing ) and dermal hazard quotient (HQ derm ) obtained, it was suggested that there is no significant risk of non-carcinogenic effects (< 1). However, they had higher HQ ing values compared to HQ derm , indicating that REEs pose more significant risk to human health through oral ingestion absorption than dermal absorption., Competing Interests: Declarations. Ethical Approval: This article does not contain any studies with human participants or animals performed by any of the authors. Consent to Participate: Not applicable. Consent for Publication: Not applicable. Competing Interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Currently for engineered nanomaterials (ENMs), there are no alternatives to bioaccumulation testing in fish as prescribed by OECD TG 305. New approaches are being sought, in order to reduce the numbers of animals used and address the ethical concerns associated with the use of vertebrates in such testing. This study aimed to demonstrate the value of an alternative method - the in chemico digestibility assay - as a tool to assess the bioaccumulation potential of ENMs. Titanium dioxide ENMs, or their equivalent bulk form, were incorporated onto a commercial fish diet and the fish digestion process was simulated in vitro at pH 2 (simulated stomach phase) and pH 7.8 (simulated intestinal phase). Only the 1000 mg/kg dry weight feed treatment showed measurable Ti release in the stomach phase, with the results being similar for the TiO 2 ENM and the bulk form. More Ti from TiO 2 was released from the feed during the intestinal phase of digestion compared to the stomach phase, but there were no statistically significant differences between either the ENM or bulk form. There was higher incidental Ti release from untreated control feed in the intestinal phase compared to the stomach phase. On a percentage basis, the stomach generally showed a statistically significant digestibility of around 3% of the total Ti in the feed, compared to around 7% in the intestine. The in chemico digestibility assay shows potential for use in the determination of the bioaccessible fraction of ENMs, and could be a useful screening tool to identify ENMs of concern for bioaccumulation., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Environmental problems persist due to mercury from artisanal and small-scale gold mining (ASGM) as well as ecological problems associated with the macrophyte Eichhornia crassipes Martius (EC). Environmental problems persist due to mercury contamination from artisanal and small-scale gold mining (ASGM) and ecological issues related to the macrophyte Eichhornia crassipes Martius (EC). A bioaccumulation study was conducted on mercury-laden wastewater (WWm) from ASGM using a pilot treatment plant, specifically a constructed wetland system (CW) with the macrophyte species EC. The study monitored the CW for 50 days, with the initial mercury concentration in the wastewater being 62.4 µgTHg L -1 , a hydraulic retention time (HRT) of 1 h, a flow rate (Q) of 0.3 L s -1 , and 7.3 kg of EC. After bioaccumulation, the EC tissues containing mercury were treated using a recovery system (RT) through thermal separation at 400 °C for 10 min. A mathematical model (AcMod) was developed to simulate bioaccumulation under continuous flow and non-stationary conditions, with a kinetic constant (k) of 0.01148 h -1 , to compare simulated data with real data from the CW. The CW showed an 89% reduction in mercury. However, the AcMod simulation indicated low bioaccumulation yields due to the low biomass of EC used. The thermal separation system reduced the total mercury (THg) in EC tissues by an average of 87.43%. The combination of CW and RT offers a nature-based solution (NBS) and promotes the circularity of resources and waste, demonstrating how this system can be integrated into the production process of ASGM., Competing Interests: Declarations. Consent to participate: This article does not contain any study with human and animals performed by any of the author. Consent for publication: The authors have consented to the submission of the study to the journal. Competing interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Hydroelectric plants impact the dynamics of mercury accumulation and transfer to aquatic ecosystems and organisms. This study aimed to determine total mercury (THg) concentration in filtered water, aquatic macrophytes, and fish and assess the influence of fluvial regime (low-water, rising-water, and high-water) and the feeding habits of fish species caught upstream and downstream of the Curuá-Una hydroelectric dam in the Brazilian Amazon. THg levels were determined by cold-vapor atomic fluorescence spectrometry. THg concentration in filtered water was higher (5.3-11.2 ng L -1 ) during the low-water period. THg concentration in fish ranged from 0.075 to 1.160 µg g -1 in specimens caught downstream and from 0.014 to 1.036 µg g -1 in specimens caught upstream of the dam. The highest THg concentrations were detected in specimens of the piscivorous species Acestrorhynchus falcirostris (1.161 µg g -1 ) caught at downstream sites. There were significant correlations of THg concentration with the trophic level (Analysis of Variance; p ≤ 0.001) of fish species and fluvial regime (Analysis of Variance; p ≤ 0.001). The macrophyte Utricularia foliosa contained the highest THg levels in leaf tissues in the low-water period (71.4 µg g -1 ). It is concluded that THg concentration varies between fish trophic levels and fluvial regimes. Macrophytes contribute to enhancing mercury transfer and availability along the aquatic trophic chain., Competing Interests: Compliance with ethical standards. Conflict of interest: The authors declare no competing interests. Informed consent: All authors consent their participation., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The Wanshan mercury mining area (WMMA) in Guizhou Province, China, has been identified as a region at high ecological risk owing to heavy metal contamination. This study employed non-lethal sampling methods, using the phalanges of Pelophylax nigromaculatus in the WMMA as analytical material. Ten heavy metal (metalloid) elements were selected for analysis, including Hg, Cr, Mn, Ni, Cu, Zn, Cd, Pb, As, and Se. These elements were measured using inductively coupled plasma mass spectrometry (ICP-MS), while Hg was determined using atomic fluorescence spectrometry (AFS). The bioaccumulation characteristics of heavy metals in P. nigromaculatus were analyzed through the bioaccumulation factor (BAF), and the extent of heavy metal pollution along with potential ecological risk was assessed using the potential ecological risk index (RI). The scaled mass index (SMI) was utilized to evaluate the body condition of P. nigromaculatus. Additionally, a combination of Spearman correlation analysis and non-negative matrix factorization (NMF) was employed to identify the sources and contributions of heavy metal elements. The results indicated that the distribution characteristics of heavy metal elements in the phalanges of P. nigromaculatus varied. Except for Pb, the concentrations of essential trace elements were significantly higher than those of non-essential elements. The bioaccumulation potential of P. nigromaculatus for heavy metal elements in the soil was found to be low, whereas the exposure risk from heavy metals in the water was high. The presence of heavy metal elements poses a significant potential ecological risk to P. nigromaculatus, with Hg, Cd, and As identified as the primary contributors to this risk. The environmental sources of heavy metals were identified as follows: Hg, Pb, Zn, and Se mainly originated from mining pollution sources; As and Cd primarily came from atmospheric pollution sources; Cr and Cu were mainly from natural activities sources; and Mn and Ni had multiple composite sources. Although heavy metal pollution negatively impacted the physical condition of P. nigromaculatus, no significant differences in SMI were observed across different regions. We believe that this is primarily attributable to the high levels of Se, which effectively mitigate the toxicity of heavy metals. The study demonstrated that using frog phalanges for heavy metal bioaccumulation analysis and SMI for physical condition assessment are simple, safe, and non-lethal methods, which can serve as useful indicators of environmental pollution and help trace the sources of environmental pollutants., Competing Interests: Competing interests: The authors declare no competing interests. Ethics approval: The manuscript did not contain any reporting studies involving human data. Consent to participate: The authors are unanimously agreed to participate in study. Consent for publication: The authors are agreed for publication of this work., (© 2024. The Author(s).)

A field study on the occurrence and distribution of forty-three pharmaceutically active compounds (PhACs) in water and fish samples from anthropogenically impacted section of the Sava River (Croatia) was performed to estimate the importance of bioaccumulation for the environmental risk assessment of PhACs. The study was performed using a highly specific LC-MS/MS method, tailored to include the most prominent PhACs from different therapeutic categories as well as their major metabolites and/or transformation products (TPs). The results revealed a widespread occurrence of PhAC residues both in water and fish samples with a large spatial variability reflecting the distance from the dominant wastewater discharges. The most prominent PhAC categories in less polluted upstream part of the river were common psychostimulants caffeine and cotinine, therapeutic opioids and cardiovascular drugs, while in the river section affected by the local municipal and industrial wastewater inputs, antibiotic drugs became clearly predominant, especially in fish tissue samples. The apparent bioconcentration factors (BCFs) of investigated PhACs varied over several orders of magnitude, from 0.02 ± 0.01 L kg -1 for O-desmethyl tramadol in fish muscle to 784 ± 260 L kg -1 for terbinafine in fish liver, indicating rather large differences in their bioconcentration potential and affinity to different tissues, with the tissue-specific BCFs increasing in the following order: muscle < gills < gonads < heart < liver < kidneys. The bioconcentration potential of most of the PhACs included in this study was only low to moderate however moderately high BCFs of certain PhACs (e.g. sertraline, terbinafine, loratadine, diazepam and azithromycin) in some tissues should be taken into consideration when assessing their potential environmental risks. Moreover, it was shown that BCFs could be strongly affected by biotransformation in fish. Risk prioritization based on risk quotient (RQ) and ToxPi index, revealed antibiotics, in particular azithromycin, and therapeutic psychoactive substances as the most hazardous pharmaceutical contaminants in the Sava River., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Understanding the sediment release and plant bioaccumulation of per- and polyfluoroalkyl substances (PFASs) under submerge-emerge alternation (SE) is crucial to predicting their transport and fate in the riparian zones. In the present study, a simulational device was firstly constructed to explore the effects of SE on the transport of PFASs in riparian sediment-plant systems and the underlying mechanisms. The submerge (CS) and emerge (CE) situations were compared. The results showed that SE significantly enhanced the transport and bioaccumulation of PFASs in sediments. Compared with the initial concentration, PFASs in sediments decreased by 81.84 %, 50.48 %, and 21.68 % in the SE, CS, and CE groups, respectively. The bioaccumulation of PFASs in plant roots in the SE group was 1.26 and 4.16 times higher than that in the CS and CE groups, respectively, and the bioaccumulation of PFASs in leaves in the SE group was 2.05 and 1.71 times higher than that in the other two groups. Dissolved organic matter (DOM) composition and molecular properties under SE were recognized as the dominant factors regulating the release of PFASs from sediments. Root morphology and low-molecular-weight organic acids (LMWOAs) in root exudates were closely associated with the bioaccumulation of PFASs in plants. Among the substitutes, hexafluoropropylene oxide trimer acid (HFPO-TA) demonstrated greater hydrophobicity, hexafluoropropylene oxide dimer acid (Gen-X) had greater mobility, and 6:2 fluorotelomer sulfonate (6:2 FTS) accumulated more in plants. This study has expanded the understanding of the geochemical cycling of PFASs in riparian sediment-plant systems under submerge-emerge alternation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Per- and Polyfluoroalkyl Substances (PFAS) are a group of water-soluble chemicals used for decades with important industrial and commercial applications. Due to their chemical and thermal stability, persistence in the environment, and widespread human exposure, PFAS become an important concern for public health. In this study, eleven highly prevalent PFAS and a reference mixture were selected according to various drinking water sources. The nematode, Caenorhabditis elegans, were exposed to PFAS at 0.1, 1, 10, 100, and 200 μM, and the toxic effects on learning & memory along with the bioaccumulation were investigated using a high-throughput screening (HTS) platform. Our results showed that perfluorooctanesulfonic acid (PFOS) and perfluorobutanesulfonic acid (PFBS) exhibited significant inhibitory effects (p < 0.05) on learning and memory in both time points at concentrations between 100 and 200 μmol/L. After 48 h of exposure, every PFAS resulted in an inhibition of learning and memory with a concentration of 200 μmol/L. Furthermore, the PFOS and PFBS had the highest bioaccumulation levels after 48 h of exposure. These findings provide valuable insight into the developmental adverse effects associated with exposure and the bioaccumulation of both individual and mixtures of PFAS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Potentially toxic elements such as arsenic (As), cadmium (Cd), and chromium (Cr) are severely regulated in fertilizers and deserve continuous investigation. Phosphate-derived Cd has been a stepping-stone toward achieving sustainable and safe worldwide food production, especially after a new regulation aiming for reduced limits of Cd in P fertilizers (EU, 2019/1009). Three pot experiments were conducted to assess the variability of As, Cd, and Cr concentrations - with a particular focus on Cd - from monoammonium phosphates (MAP 1, MAP 2, and MAP 3 from different geographic origins) and their accumulation in limed and unlimed soils, and contrasting crops, representing staple food and significant sources of these elements for humans (i.e., potato, tobacco, and rice). A diverse array of sensitive techniques for trace elements determination were used to reveal the highest level of Cd of MAP 3 (20.71 mg kg -1 MAP), which loaded the highest amounts of this element to the soil matrix and solution, plant shoots, and xylem sap, contrasting with results for MAP 1 (0.87 mg kg -1 MAP), which has almost ten times less Cd than that required for low-Cd labeling of P fertilizers (≤20 mg Cd kg -1 P 2 O 5 ). MAP 3 also had the highest Cr concentration (139.3 mg kg -1 MAP). Among crops, rice accumulated 16-fold less Cd than potato plants. Liming decreased Cd in tobacco and potato shoots up to 35%. Moreover, reductions of about 20% were also observed for Cd accumulation in tubers and sap. Conversely, Cd from MAP 3 was always much more accumulated in soil solution, achieving up to 20 μg L -1 , while values < 5 μg L -1 (i.e., a groundwater limit) were obtained from MAP 1. Our findings may be used as a reference in developing green labels for fertilizers in scenarios where Cd accumulation represents a potential risk for soil and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Ingestive uptake is critical for understanding the accumulation and trophic transfer of chemicals and synthesized particles in general. This study explored the contribution of ingestion in the bioaccumulation of chemicals focusing on worms. Novel theory and equations were developed to derive fractional ingestive contribution, f s , from a broad range of dietary uptake and accumulation studies, and to build a small dataset of f s (n = 43) from relevant toxicokinetic and bioaccumulation measurements. Worm f s could be fitted to log K OW -based sigmoidal models with small errors (RSE < 0.15, RMSE<0.15). The basis and limitations of the applied f s equations were elaborated. These included the assumption that aqueous-based and dietary-based elimination rate constants (k T w ) may be statistically equivalent, as demonstrated using fish and worm data. Bioaccumulation and toxicokinetic parameters obtained at under-exposed conditions can also result in non-sensical, negative f T S theory suggested a novel way to model bioaccumulation in the presence of aqueous and solid sources, and the potential to consolidate bioaccumulation data in their variant forms and definitions for assessment, modeling, and benchmarking purposes. While the presented f s . The developed f s theory suggested a novel way to model bioaccumulation in the presence of aqueous and solid sources, and the potential to consolidate bioaccumulation data in their variant forms and definitions for assessment, modeling, and benchmarking purposes. While the presented f s chemicals questioned the validity of characterizing and regulating bioaccumulation potential of hydrophobic organics - for which dietary uptake matters - using aqueous-only bioconcentration factor (BCF). This question, along with other less important ones, is yet to be explored in future works.OW dependence remained to be explored in other species, the importance of ingestive uptake for high-log K OW chemicals questioned the validity of characterizing and regulating bioaccumulation potential of hydrophobic organics - for which dietary uptake matters - using aqueous-only bioconcentration factor (BCF). This question, along with other less important ones, is yet to be explored in future works., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dave Ta Fu KUO reports financial support was provided by National Science and Technology Council. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Settleable atmospheric particulate matter (SePM), from steelmaking processes, contains a complex mixture of metals, metalloids, and metallic nanoparticles. The SePM is released airborne and disperses in water, representing a significant threat to aquatic life, particularly fish. This study investigated the effects of a sublethal and environmentally relevant concentration of SePM (1 g·L -1 ) for 96 h in the gill, liver, kidney, and white muscle of Nile tilapia (Oreochromis niloticus), employing exposure and effect biomarkers to test causality between metal accumulation and biochemical responses. The gills and liver showed the highest bioaccumulation of metals and integrated response index value, indicating susceptibility to metal accumulation. However, the gills produce a protective mucus layer that may mitigate metal toxicity. The kidneys and muscle tissue also showed bioaccumulation of metals, although to a lesser extent. The liver and kidneys experienced oxidative stress, characterized by reduced metallothionein and glutathione levels, as well as damage to lipids, proteins, and DNA. The accumulation of less-studied metals, particularly Rare Earth Elements (REEs), compromised the integrity of biomolecules in these tissues. In conclusion, the complex dynamics of metal bioaccumulation in Nile tilapia exposed to SePM reveal varied tissue responses and primary effects like oxidative damage. They also highlight the need for further research and regulation of other metals and their potential impacts on aquatic ecosystems and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The bioaccumulation and trophic transfer of pollutants in marine ecosystem members determine their ultimate ecological risks. Food web bioaccumulation models are widely used in scientific and regulatory programs to assess the bioaccumulation and ecological risks of pollutants at the ecosystem scale. The food web models are mainly established through concentration- and fugacity-based modeling approaches and include some chemical, food web-related, physiological and environmental factors. The models applied in the "forward approach" predict bioaccumulation and conduct internal exposure level-based ecological risk assessment (IEL-ERA), whereas those in the "reverse approach" are used to back-calculate the IEL-based predicted no-effect concentrations (PNECs) or environmental criteria. However, some challenges still exist in the application of food web model integrated risk assessment, including the lack of standardized/generalized frameworks, the lack of chemical- and species-specific toxicokinetic data and internal exposure (or tissue residue)-based toxicity data, and the lack of uncertainty-control methods in model estimation and parameterization. There are urgent requirements to improve models, integrate methods and update study designs in the assessment and prediction of "system-scale risks" of marine emerging organic pollutants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The bioaccumulation potential of contaminants in marine environments was investigated in biofilms and compared with caged mussels for a wide range of both organic and metallic contaminants across a large geographic area. Marine biofilms were sampled after three months of sub-surface immersion at 49 locations along the 1800 km of the French Mediterranean coast. Ten chemical elements (i.e. As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) and 57 organic compounds (i.e., 18 polycyclic aromatic hydrocarbons (PAHs), 8 dioxin-like and 6 non-dioxin-like polychlorinated biphenyls (PCBs) and 25 organochlorine pesticides (OCPs)) were quantified in triplicates, revealing different multi-contaminated profiles depending on sites. Most of contaminants exhibited higher concentrations in biofilms than in mussels. Moreover, a remarkable significant and positive correlation between the concentrations in both biological matrices was observed for PAHs and PCBs, and more contaminant-dependent for OCPs and metals. These results highlighted the potential of biofilms as relevant bioindicators of the marine chemical contamination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Repeated addition of activated carbon (AC) via the water column was applied to rejuvenate sorption capacity of thin AC-amended sand caps placed over polychlorinated biphenyl- (PCB) contaminated marine bed sediment receiving ongoing input of sediment (contaminated or clean) in mesocosms. Bioaccumulation of PCBs in sheepshead minnows (Cyprinodon variegatus) from bed sediment was reduced by repeated application of rejuvenating AC when the ongoing input was contaminated. However, when the input sediment was clean, the novel AC addition increased fish uptake of bedded PCBs in the first 60-days of the 90-day experiments. The 79 % increase of bedded PCB bioaccumulation in fish, for clean versus contaminated inputs, was statistically significant (p < 0.05) in experiments where the rejuvenating AC was applied. Equilibrium concentrations in low-density polyethylene (LDPE) passive samplers did not fully explain bioaccumulation. Field implications of this research include setting appropriate temporal expectations of this novel remediation strategy regarding the primary desired effect (i.e., PCB bioavailability reductions)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Citation of trade names utilized in this study does not constitute an official endorsement or approval of the use of such commercial products. Any opinions, findings, conclusions, or recommendations expressed in this article are those of the authors and not necessarily the views of the US Army Corps of Engineers, or the US Environmental Protection Agency., (Published by Elsevier B.V.)

Despite a good knowledge of cadmium accumulation in Gammarus fossarum, studies to date have focused on Cd accumulated via the dissolved pathway, leaving aside the trophic pathway. The aim of this study was to assess cadmium organotropism and bioaccumulation processes following a trophic exposure of the species Gammarus fossarum. Adult male gammarids were fed with 109 Cd contaminated alder leaves discs for 6 days and then with clean alder leaves for 12 days. During both phases, some gammarids were collected and dissected, and intestines, hepatopancreas, cephalons, gills and remaining tissues were separated to measure their Cd concentrations. Their relative proportions of Cd and their respective BMFs were estimated. The ingestion rate (IR) measured during the exposure phase was divided by 3 between days 2 and 6, indicating that gammarids reduced their feeding activity and therefore the exposure pressure. A multi-compartments TK model was developed, and an iterative inference process was run to select the most parsimonious model that best fits all organ datasets simultaneously. The results showed that: i) intestine and hepatopancreas bioconcentrate Cd the most; ii) no cadmium was quantified in gills, meaning that they do not appear to play a role in Cd storage or elimination with a trophic exposure; iii) Cd elimination occurs only through the intestine; and iv) the general pattern of Cd fate in gammarids, obtained here after dietary highlights once again the importance of the intestine and hepatopancreas, as for the dissolved pathway., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

An eight-compartment physiologically based pharmacokinetic (PBPK) model was used to simulate the bioaccumulation and distribution of arsenic (As) within the apple snail (Pomacea canaliculata) following the ingestion of As-contaminated lettuce. The bioaccumulation results revealed that the shell contained the majority (67.21 %) of the total As content, with the liver and the head-foot containing approximately 11.14 % and 10.45 % of the total As content in the snail, respectively. Modeling quantified the process of intestine-stomach absorption of dietborne As and revealed its crucial role in the subsequent distribution of As within the body. The liver is the primary metabolic site, whereas the shell is the primary storage site. Exposure to dietborne As leads to pronounced physiological and biochemical alterations in apple snails. Total protein levels decreased by 24.06 %, superoxide dismutase (SOD) activity decreased by 24.43 %, malondialdehyde (MDA) content increased by 47.51 %, glutathione (GSH) content decreased by 46.99 %, and glutathione S-transferase (GST) activity decreased by 42.22 %. Furthermore, the subcellular-level results indicated that dietborne As exposure altered subcellular distribution in the liver. Additionally, dietborne As exposure significantly reduced the abundance of gut microbiota in apple snails., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Sediments act as important sinks for metals and their radionuclides in aquatic environments and play a crucial role in their transfer and uptake to aquatic organisms. Traditional radioecological models use radionuclide concentrations in water to predict concentrations in aquatic organisms. In this study, we investigated the distribution of radioecologically important metals (Ba, Co, Ni, Sr, U) among sediment, porewater and hypolimnion over seasons. We also studied the uptake of these metals to benthic organisms and importance of sediment as an uptake source by conducting a 28-day in situ bioaccumulation experiment with oligochaete worms (Lumbriculus variegatus). The studied metals were chosen based on common occurrence of their radioactive isotopes in nuclear fuel cycle. Measurements of total elemental concentration were used as proxies to study the behavior of specific radionuclides. Sediment and water samples were collected from two small lakes connected to a former uranium mine in Eastern Finland, and from a nearby reference lake connected to a different drainage area. Environmental characteristics and concentrations measured from sediment, porewater and overlying water indicated only minor changes between seasons. Measured metals were highly associated with sediment particles, rather than porewater or hypolimnion. Both the distribution of metals and in situ experiment indicated the importance of sediment as the main source of bioaccumulation. Significant differences in Ba, Ni and U concentrations between treatments containing contaminated sediment and reference sediment were noted, regardless of water concentrations. Additionally, as U contaminated lakes lacked seasonal overturn during our monitoring period, metal distribution and environmental conditions remained unchanged in deeper parts of those lakes. Lastly, the results of this in situ bioaccumulation experiment are in line with the findings of our previous laboratory study using sediments from these same lakes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Determining the extent of pollution in the marine environment remains challenging. Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and metals can, during dredging operations, be transported from a port or harbour into the open sea, where they may exert a harmful effect on the marine ecosystem. To fully understand the impact of these chemicals, monitoring programs should not only focus on sediment concentrations, but should also take into account the bioaccumulated concentration in the tissue of multiple target organisms. In this study, the concentration of primary contaminants is determined in common starfish (Asterias rubens), flying crab (Liocarcinus holsatus), and brown shrimp (Crangon crangon) and the difference in the concentration of contamination between different dredge disposal sites at open sea is investigated. Different factors such as lipid weight, dry weight, grain size, and total organic carbon were measured and used to understand the difference between the observed bioaccumulation and the measured sediment concentrations. KEY MESSAGE: Different contaminants are detected in biota such as common starfish, flying crab and brown shrimp. These contaminants can be linked to dredging activities, with disposal sites associated with industrial ports showing higher contamination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The demand of lithium (Li) has increased rapidly in recent decades under carbon neutrality strategies, but the environmental fate and potential risks of Li in aquatic ecosystem are barely known. This study conducted a comprehensive field survey in the Yangtze River Estuary (YRE) and the adjacent East China Sea (ECS), to investigate the spatial distribution of dissolved Li and bioaccumulation of Li in the coastal food web. The dissolved Li increased with salinity (from 7.39 to 189 μg L -1 ), controlled by the conservative mixing of Li-enriched seawater and Li-poor riverine water. Negative correlation was observed between Li content and stable nitrogen isotope in the coastal biota, indicating bio-diminish of Li in the food web. Furthermore, the Li contents in muscle tissues were significantly higher in bivalves (as filter-feeders; mean: 0.75 ± 0.41 μg g -1 ) than in fish (as predator; mean: 0.10 ± 0.05 μg g -1 ) and other biota species, indicating that dissolved uptake might be the major exposure pathway for Li. Importantly, it was noticed that the bioaccumulation factors (BAFs) in fish muscle varied greatly (from 0.17 to 5.82), showing lower BAFs for fish inhabiting in marine and benthic regions (with higher salinity and higher dissolved Li concentration). Such inhibition effects of salinity on Li bioaccumulation could not be explained by the modulation of salinity on Li speciation, but highly attributed to the inhibition of high salinity on the dissolved uptake of Li, which was associated with the co-transportation of Li and Na. Our results illuminate the importance of salinity on regulation the spatial variations of dissolved Li and Li bioaccumulation in the YRE and the adjacent ECS, which could help the understanding of Li biogeochemical cycling and potential risks in estuarine and coastal regions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microplastics are a novel pollutant that adversely affect freshwater benthic organisms. However, few studies have investigated the mechanism underlying the bioaccumulation and the toxicity of microplastics. In this study, microplastics bioaccumulation of wild Cipangopaludina chinensis in the Songhua River were utilized, and a 28-day aquatic toxicity test was performed to determine the effects of exposure to polyethylene terephthalate (PET), the bioaccumulation of PET, and changes in multiple biomarkers in the muscle, gill, and kidney tissues. The concentration pattern of microplastics was as follows: kidney tissue > muscle tissue > gill tissue. Microplastic ingestion caused AChE inhibition led to significant increases in redox and energy metabolism indicators. Furthermore, the IBR analysis presented a "response-resistance-breakdown" process, indicating that Cipangopaludina chinensis possessed resistance with time (D14 and D21) and concentration (0.10 mg/L and 1.00 mg/L) thresholds. Tissue sensitivity to microplastics was ranked as gill > muscle > kidney, which was the opposite order of microplastic accumulation. These findings implied that less sensitive tissues stored a larger amount of pollutants, suggesting a reduction in tissue sensitivity to microplastics with higher microplastic occurrence rates. This study provides new insights into biological resistance to pollutant stress, warranting further investigation into the underlying mechanisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Numerous antibiotics have been detected in aquatic ecosystems and induced severe toxic effects on aquatic organisms. However, mechanisms of bioaccumulation and trophic transfer of antibiotics are not adequately discussed, to the best of our knowledge. In this context, the bidirectional selective effect values (BSEV) and trophic transfer efficiency ratio (TTER) of 24 antibiotics in a simulated food chain (Chlorella sorokiniana-Daphnia magna-Danio rerio) were first calculated to mirror the bioaccumulation and biomagnification. Based on estimates above, the multi-output machine learning (ML) models, including K nearest neighbor (KNN), Support vector machine (SVM), Extremely randomized trees (ERT) and Extreme gradient boosting (XGBoost), were constructed, followed by molecular dynamics (MD) simulation and density functional theory (DFT) calculation to explore the bioaccumulation and biomagnification mechanism. According to our results, sulfonamide antibiotics had greater capacity biomagnification, while β-lactam and tetracycline antibiotics showed opposite results. Meanwhile Cytochromes P450 (CYP450) in Danio rerio played a key role in the food chain. The ERT model exhibited reliable prediction with indicators of R 2 = 0.816, MAE = 0.039, MSE = 0.003, RMSE = 0.053 and MAPE = 8.923. The AATS5s was identified as the most contributing descriptor. The differences in the atomic composition, structure and binding ability to enzymes of antibiotics lead to the differences in their bioaccumulation. Van der Waals interactions (ΔE vdw ) and non-polar interactions (ΔG nonpolar ) were the main driving energy for the biometabolism capability of antibiotics. Tetracyclines are the most readily biometabolized, whereas sulfonamides are more difficult to biometabolize due to their low binding capacity and low reactivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Polycyclic aromatic hydrocarbons (PAHs) are persistent pollutants in aquatic environments that can accumulate in marine organisms and pose potential health risks to humans through trophic transfer in the food webs. However, the accumulation and health risks of PAHs in organisms at different trophic levels remain unclear. This study investigated the accumulation and trophic transfer of PAHs in 40 marine organisms from Beibu Gulf (China), and assessed their health risks. Utilizing the trophic level spectrum constructed with stable isotope methods, the organisms were categorized into three trophic levels: Omnivorous (15.00 %), low-level carnivorous (67.50 %), and mid-level carnivorous (17.50 %). The contamination levels of total PAHs in these organisms ranged from "mild pollution" to "moderate pollution", with all organisms exhibiting significant PAH accumulation (Bioconcentration factor value > 2000). Total PAH concentrations increased with higher trophic levels, following the trend of mid-level carnivores > low-level carnivores > omnivores. Notably, only three PAH compounds (Nap, Fla and Phe) showed biomagnification effects, while the others exhibited trophic dilution. Carcinogenic risk assessment indicated an "Unacceptable risk" level for all populations, with the highest risk due to consumption of mid-level carnivorous. These findings offer new insights into the accumulation and health risks of PAHs from a trophic transfer perspective., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

One challenging task to produce rice that comply with the increasing demanding regulations, is to reduce, simultaneously, grain bioaccumulation of As, Cd, and Pb. A 3-year field experiment was conducted in a Mediterranean environment, to evaluate the effects on As, Cd, and Pb bioaccumulation in rice grain, of the adoption of two levels of alternate wetting and drying (AWD) irrigation conditions: moderate and intensive (reflooding at -20 kPa and -70 kPa soil matric water potential, respectively), relative to the traditional permanent flood irrigation. Plots were prepared with or without a one-time holm oak biochar application (35 Mg ha -1 ), in the first year of the study. Arsenic bioaccumulation decreased in rice grain in the AWD systems, both total and inorganic (As Inorg ), with the lower values reached in the intensive AWD irrigation (0.131-0.151 mg kg -1 dry weight), when the drying conditions were more intense. For As, biochar contributed to a further reduction in the bioaccumulation in the first two years but lost its efficacy with the field aging after three years of its application. However, the transition to AWD irrigation led to a significant increase in Cd bioaccumulation in rice grain (21-fold increase in the more intensive system, whose values reached up to 0.127 mg kg -1 ), which can be counteracted by biochar application, to values statistically similar to those of permanent flooding. Contrariwise, the effects on Pb bioaccumulation were not so significant, but decreased with the transition to ADW irrigation, and with biochar application, relatively to the non-amended counterparts. Therefore, the implementation of intensive AWD with biochar represents a potentially fruitful strategy to enhance food safety of rice production, controlling, simultaneously, As, Cd, and Pb bioaccumulation. Nevertheless, new approaches need to be developed to attend the limits established for As Inorg to produce food for infants, even in uncontaminated soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The antiepileptic drug carbamazepine (CBZ) has been widely detected in freshwater, yet its toxic actions in fish at multiple endpoints and the subsequent recovery patterns of the impacted are less discussed. This study investigated the bioaccumulation, physiological and behavioral changes of crucian carp (Carassius carassius) following CBZ exposure (G1 = 6.15 μg/L, G2 = 61.5 μg/L, G3 = 615 μg/L, G4 = 6150 μg/L) and subsequent recovery. Our results showed that CBZ was more likely to accumulate in the liver and brain than in the gills. A concentration-dependent phenomenon was observed; however, the residual CBZ decreased to similar levels after recovery. The behavioral indicators (i.e. feeding, social and spontaneous swimming) were significantly inhibited after 7-days of CBZ exposure, and only recovered at low concentration treatment (G1) after 7-days recovery in CBZ-free water. The acetylcholinesterase (AChE) activity in the brain and superoxide dismutase (SOD) activity in the liver and gills were induced after CBZ exposure and returned to normal levels after 7-days of recovery. In contrast, the inhibition of catalase (CAT) activity caused by CBZ exposure persisted in the high concentration treatment (G4) after recovery. Furthermore, correlation analysis indicated that changes in feeding behavior were closely related to the variation of CBZ concentrations in tissues, and the persistence of abnormal swimming and social behavior was closely related to gill CAT activity. These findings contribute to explore the toxic mechanisms of CBZ and highlight the recovery process and connections between various endpoints., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microplastics (MPs), a growing environmental concern with potential ecotoxicological risks, are ubiquitous in aquatic environment. This study investigated the organ-specific distribution and variation of MPs in commercially caught fishes (7 species, 140 individuals) collected from Dhaka's two main fish distribution hubs (Uttara and Jatrabari). Additionally, the impact of different-sized MPs on fish growth (Anabas testudineus) was examined in a control experiment. Results revealed that kidneys of market fish bioaccumulated the highest concentration of MPs (average, 59.1 MPs/g), followed by liver (24.6 MPs/g) and intestine (18.6 MPs/g). On average, fish from Uttara had a higher MPs concentration (36 MPs/g) compared to Jatrabari (25 MPs/g). Among fish species, Glossogobius giuris showed the highest MPs bioaccumulation due to its feeding habits and morphology. Fiber-shaped MPs were most prevalent in all fishes (79-93%) except Glossogobius giuris (fragments, 51%). Fourier-transform infrared spectroscopy (FTIR) analysis identified 19 different polymer types, with high density polyethylene (HDPE), ethylene vinyl acetate (EVA) and polyamide (PA) being commonly found in all organs. The experimental study confirmed that large-sized PVC MPs (1.18 mm-300 μm) had a greater negative impact on fish growth (length) and caused more physical deformities (particularly intestinal injuries) compared to small-sized PVC MPs (150 μm-75 μm). Moreover, fish exposed to larger diameter MPs experienced highest physical weight and depth loss among exposed groups. Large-sized PVC MPs bioaccumulated highest in fish compared to small-sized PVC MPs. Similar to market fish, kidney in the experimental fish had the highest MPs bioaccumulation (6.5 MPs/g), followed by liver (5.2 MPs/g) and intestine (4.8 MPs/g), with a dominance of fibers despite the presence of high concentration of fragments in the food source. Statistical analysis also supported a clear correlation between increasing MPs size and adverse effects on fish growth and health. Urgent action is needed to curb microplastic pollution and protect ecosystems and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Unpolluted freshwater is a crucial component for maintaining the health of humans. This study aimed to investigate the bioaccumulation and potential health hazards of heavy metal contaminants (Fe, Cd, Cr, Cu, Pb) in water, sediments, and tissues of the golden mahseer fish (Tor putitora) from Zhob River to assess their suitability for human consumption. Samples (soil, water, and fish) were collected from the Zhob River, and Flame Atomic Absorption Spectrometry (FAAS) was employed to measure the concentration of these metals found in soil, water, and various fish body tissues (muscles, skin, gills, and liver). The overall results revealed that water quality parameters, i.e., temperature and pH were found within tolerable ranges, while electrical conductivity and turbidity exceeded the permissible limits of FAO/WHO for fish. Furthermore, this study also identified elevated concentrations of Pb in water and soil, as well as Fe and Cd in soil beyond the standards set by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA). In contrast, the concentrations of other targeted metals examined in fish body tissues were found below the permissible limits set by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO), indicating the suitability of this fish species for human consumption. The estimated daily intake (EDI) of these targeted metals in various fish body tissues was found to be within the recommended dietary allowance (RDA), suggesting no associated health risks for the local population. Furthermore, both the Target Hazard Quotient (THQ) and Total Target Hazard Quotient (TTHQ) values measured in this study were less than one, indicating the absence of potential non-carcinogenic health risks related to the consumption of this riverine mahseer fish, but combined metal intake may pose potential health risks. Carcinogenic risk assessment for some metals like Cd, Cr, and Pb revealed no cancer risk for consumers. Moreover, our present research observed comparatively high bioaccumulation (BAF) of each targeted metal in the fish liver from both Zhob River water and soil as compared to other body tissues. Multivariate analysis, including the correlation matrix, revealed strong and significant correlations (P < 0.05) among heavy metal pairs (Fe/Cr, Fe/Pb, Cr/Fe, Cr/Pb, Pb/Fe, Pb/Cr). Hierarchical cluster analysis and Principal Component Analysis (PCA) were utilized to trace the origins of these metals, attributing their presence to nearby rock weathering, mining, as well as municipal and agricultural activities. These factors were recognized as potential sources of heavy metal bioaccumulation in riverine fish. Thus, our current study concluded that the Zhob River was contaminated with these heavy metals and emphasized the need to prevent domestic and industrial sewage inflow. The monitoring of these metals in the food chain was also underscored as crucial for reducing all kinds of associated health risks. This study provides the first report on heavy metal distribution in highly abundant and edible mahseer fishes of the Zhob River., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Zubia Masood reports administrative support, article publishing charges, equipment, drugs, or supplies, statistical analysis, travel, and writing assistance were not provided by Sardar Bahadur Khan Women's University. Zubia Masood reports a relationship with Sardar Bahadur Khan Women's University that includes: non-financial support. Zubia Masood has no patent. All authors have no relevant financial or non-financial interests to disclose that can influence this publication. Other authors have also declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Mercury, a toxic metal released by various human activities, exerts environmental stress through its bioaccumulation and biomagnification, particularly in marine habitats. South American fur seals (Arctocephalus australis) and sea lions (Otaria flavescens) reproduce on the Atlantic coast of Uruguay. As top predators, they can accumulate toxic levels of mercury and are often used as sentinel species for monitoring ecosystem health. Fur seals prey on pelagic species, such as fish and squid, while sea lions consume coastal-benthic prey. We analyzed the total mercury concentration (THg) in hair and the trophic habits (δ 13 C and δ 15 N) of females from both species. The average THg concentration in adult female sea lions (30.5 ± 9.3 μg/g dry weight) was significantly higher than in fur seals (6.3 ± 2.5 μg/g dry weight). Additionally, the mean δ 15 N and δ 13 C values were significantly higher in sea lion (δ 15 N: 19.2 ± 0.6‰, δ 13 C: -13.8 ± 0.2‰) compared to fur seals (δ 15 N: 16.5 ± 0.5‰, δ 13 C: -15.5 ± 0.6‰). Our results suggest that different trophic levels and feedings areas affect the THg concentration in Uruguayan Otariids. Notably, at the intraspecific level, the THg concentration in sea lions increased with δ 13 C values, suggesting a link to coastal feeding habits. This indicates that coastal feeding behaviors, compared to feeding in pelagic environments, enhance mercury bioaccumulation in Otariids along the Uruguayan coast, with the discharge of freshwater from the Río de la Plata (one of the largest estuaries in South America) basin identified as a potential mercury source. THg concentrations found in female sea lion hair are the highest reported in Otariids globally. Mercury levels exceeded toxic thresholds observed in other mammals and could pose significant health risks. Our findings may explain why sea lions were particularly affected by the avian influenza outbreak in Uruguay compared to fur seals. Monitoring the declining sea lion population is crucial, making our results significant for integrated conservation and management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Due to the wastewater irrigation or biosolid application, per- and polyfluoroalkyl substances (PFASs) have been widely detected in agriculture soil and hence crops or vegetables. Consumption of contaminated crops and vegetables is considered as an important route of human exposure to PFASs. Machine learning (ML) models have been developed to predict PFAS uptake by plants with majority focus on roots. However, ML models for predicting accumulation of PFASs in above ground edible tissues have yet to be investigated. In this study, 811 data points covering 22 PFASs represented by molecular fingerprints and 5 plant categories (namely the root class, leaf class, cereals, legumes, and fruits) were used for model development. The Extreme Gradient Boosting (XGB) model demonstrated the most favorable performance to predict the bioaccumulation factors (BAFs) in all the 4 plant tissues (namely root, leaf, stem, and fruit) achieving coefficients of determination R 2 as 0.82-0.93. Feature importance analysis showed that the top influential factors for BAFs varied among different plant tissues, indicating that model developed for root concentration prediction may not be feasible for above ground parts. The XGB model's performance was further demonstrated by comparing with data from pot experiments measuring BAFs of 12 PFASs in lettuce. The correlation between predicted and measured results was favorable for BAFs in both lettuce roots and leaves with R 2 values of 0.76 and 0.81. This study developed a robust approach to comprehensively understand the uptake of PFASs in both plant roots and above ground parts, offering key insights into PFAS risk assessment and food safety., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used pharmaceuticals. Their presence in natural waters is due to the low removal efficiency in conventional wastewater treatment plants (WWTPs). Interestingly, certain zooplankton species can survive the mixture of pollution and abnormal water conditions in WWTPs. In our study, for the first time, we tested the in-situ bioaccumulation of NSAIDs and their metabolites in Daphnia pulex, which were obtained in high numbers in one WWTP during the summer. It was found that diclofenac (DCF) and 4-hydroxy DCF were present in the studied clarifiers and ponds. Among these chemicals, only DCF was detected in daphnia. The bioaccumulation factor of DCF in daphnia was below 36 L kg -1 ww and was lower than those obtained under experimental conditions for Daphnia magna. The tested daphnia adapted to chronic exposure to mixtures of drugs in μg L -1 level and could be implemented in biobased WWTPs. According to our data, there is a need to supplement the risk assessment of anthropogenic pollutants with in-situ cases to demonstrate the adaptation possibilities of wild-living organisms., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Magda Caban reports financial support was provided by National Science Centre Poland. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Prolonged consumption of foods containing toxic metals can elevate the risk of noncommunicable diseases, including chronic kidney disease of uncertain etiology (CKDu). Despite the increasing number of CKDu cases in Maradankulama and Mahakanadrawa Grama Niladhari Divisions (GN) in Sri Lanka, no prior studies have examined the accumulation of heavy metal(loid)s and their potential association with CKDu prevalence. Furthermore, there is an absence of comprehensive analyses using chemometric techniques such as PCA and hierarchical studies regarding CKDu and heavy metal contamination in Sri Lanka. This study aims to provide initial insights into the accumulation and potential pathways of toxic metals in staple foods within local diets and their subsequent presence in the agricultural environment of examined GNs. Cr, Cd, As, and Ni concentrations in analyzed foods were within permissible limits (MPLs), whereas Pb levels exceeded MPLs in rice (Oryza sativa), gotukola (Centella asiatica), lime (Citrus crenatifolia), and inland fish (Etroplus suratensis). High target hazard quotient (THQt) values in polished rice suggest possible health risks with prolonged intake. Hierarchical analysis suggested a common source of Pb accumulation. PCA and hierarchical clustering revealed the intricate connection between As and Cd, with their concurrent clustering in samples suggesting a potential common origin. This indicates that while individual concentrations comply with acceptable standards, the potential synergistic effects of Cd and As accumulation might pose elevated health risks. Further, the gut tissues of inland fish exhibited pronounced metal concentrations and significant (p < 0.05) positive correlations with toxic metals in the tank sediments suggesting a diet-based bioaccumulation pathway through sediments., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Decabromodiphenyl ethane (DBDPE) and cadmium (Cd) are typical pollutants in e-waste, seriously threatening crop growth. This study investigated the bioaccumulation and toxicity mechanisms of DBDPE and Cd in a soil-rice system. The results showed that 50 mg/kg DBDPE could reduce the level of accumulation of Cd in rice roots. DBDPE and Cd induced the antioxidant system (SOD, POD, and MDA) in rice seedlings. The combined exposure reduced the contents of carbohydrates, lipids, amino acids, and organic acids. Phenylalanine and phenylpropanoid metabolisms were identified as the key detoxification metabolic pathways under combined exposure. DBDPE and Cd disrupted the functional cycling of carbon and nitrogen in rhizosphere soil, while Gemmatimonadetes, Actinobacteria, and Bacteroidetes were the key bacterial groups responding to DBDPE and Cd stress. This work provides data for the toxicity risk evaluation of DBDPE and Cd combined exposure to food crops.

Globally, ocean dumping of chemical waste is a common method of disposal and relies on the assumption that dilution, diffusion, and dispersion at ocean scales will mitigate human exposure and ecosystem impacts. In southern California, extensive dumping of agrochemical waste, particularly chlorinated hydrocarbon contaminants such as DDT, via sewage outfalls and permitted offshore barging occurred for most of the last century. This study compiled a database of existing sediment and fish DDT measurements to examine how this unique legacy of regional ocean disposal translates into the contemporary contamination of the coastal ocean. We used spatiotemporal modeling to derive continuous estimates of sediment DDT contamination and show that the spatial signature of disposal (i.e., high loadings near historic dumping sites) is highly conserved in sediments. Moreover, we demonstrate that the proximity of fish to areas of high sediment loadings explained over half of the variation in fish DDT concentrations. The relationship between sediment and fish contamination was mediated by ecological predictors (e.g., species, trophic ecology, habitat use), and the relative influence of each predictor was context-dependent, with habitat exhibiting greater importance in heavily contaminated areas. Thus, despite more than half a century since the cessation of industrial dumping in the region, local ecosystem contamination continues to mirror the spatial legacy of dumping, suggesting that sediment can serve as a robust predictor of fish contamination, and general ecological characteristics offer a predictive framework for unmeasured species or locations., Competing Interests: Competing interests statement:The authors declare no competing interest.

This paper aims to determine the content and bioaccumulation patterns of eight trace elements (Li, Cr, Co, As, Se, Cd, Pb and Hg) and one radioisotope (U) in kidney, liver and muscle tissues of two fish species (Squalius orpheus and Barbus strumicae) from Nestos River (northern Greece), and the potential human health risk due to the fish muscle consumption. Kidney and liver accumulate higher element concentrations, except Hg. The site closer to the river-mouth presents higher concentrations since it receives effluents from agricultural activities. The upstream station shows lower element concentrations, due to obstruction of the free transportation of sediments and suspended matter downstream the irrigation dam. The sediment inhabitant and feeder B. strumicae showed elevated concentrations compared to the water column resident S. orpheus. According to calculated hazard indices, the consumption of the fish edible tissue poses zero health risk in developing chronic undesired effects in humans., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Pollution of aquatic environments with heavy metals causes severe adverse effects on fish, invertebrates, and human. The importance of this study lies in the fact that long-term ingestion of heavy metal-contaminated fish can result in the accumulation of harmful metals in numerous organs and pose a major risk to human health., Aim: The current study was designed to investigate the concentrations of toxic arsenic (As), lead (Pb), and mercury (Hg) in the liver, gills, and muscles of highly consumed aqua cultured common carp ( Cyprinus carpio L.) in Baqubah city, to evaluate the toxicopathological bioaccumulation of As, Pb, and Hg in consumed fish and the potential human health risk after consumption and give clear indication for a status of heavy metal contamination for water used in aquaculture of common carp ( C. carpio L.)., Methods: A total of 10 Fresh fish of common carp ( C. carpio L.) were randomly selected from local Baqubah markets/Diyala province/Iraq in different interval from September 2022 to January 2023. The source of fish in Baqubah's local markets is fish aquacultured in earthen ponds as well as cages in the Tigris River in Diyala province. Flame atomic absorption spectrometer was used to estimate the level of As, Pb, and Hg in liver, gills, and muscles of collected fish. Histopathological sections were prepared for evaluation of toxic pathological effects of metals on C. carpio organs., Results: Bioaccumulation of arsenic and lead in liver, gill, and muscle samples was within and less than the permissible limit set by WHO while the bioaccumulation of mercury exceeds the permissible limits set by WHO. Histopathological findings of the gill section showed telangictatisis and epithelial lifting in secondary lamellae with hemorrhage and blood congestion and central venous dilation and epithelium hyperplasia with complete fusion of the secondary lamellae and edema in the filamentary epithelium in addition to mononuclear cells infiltration. Histopathological findings of liver revealed degenerative and necrotic changes in liver tissue distinguished by pyknosis with the existence of necrosis in cells and dilation of the sinusoids with cytoplasmic vacuolation., Conclusion: The bioaccumulation of mercury is higher than permitted levels in common carp ( C. carpio ) which indicates high contamination level of main sources for fresh waters in Diyala province mainly from Diyala and Tigris rivers., Competing Interests: The authors declare that there is no conflict of interest.