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Environmental Pollution (Barking, Essex... Oct 2022Forest management can alter the mobilization of mercury (Hg) into headwater streams and its conversion to methylmercury (MeHg), the form that bioaccumulates in aquatic...
Forest management can alter the mobilization of mercury (Hg) into headwater streams and its conversion to methylmercury (MeHg), the form that bioaccumulates in aquatic biota and biomagnifies through food webs. As headwater streams are important sources of organic materials and nutrients to larger systems, this connectivity may also increase MeHg in downstream biota through direct or indirect effects of forestry on water quality or food web structure. In this study, we collected water, seston, food sources (biofilm, leaves, organic matter), five macroinvertebrate taxa and fish (slimy sculpin; Cottus cognata) at 6 sites representing different stream orders (1-5) within three river basins with different total disturbances from forestry (both harvesting and silviculture). Methylmercury levels were highest in water and some food sources from the basin with moderate disturbance (greater clearcutting but less silviculture). Water, leaves, stoneflies and fish increased in MeHg or total Hg along the river continuum in the least disturbed basin, and there were some dissipative effects of forest management on these spatial patterns. Trophic level (δN) was a significant predictor of MeHg (and total Hg in fish) within food webs across all 18 sites, and biomagnification slopes were significantly lower in the basin with moderate total disturbance but not different in the other two basins. The elevated MeHg in lower trophic levels but its reduced trophic transfer in the basin with moderate disturbance was likely due to greater inputs of sediments and of dissolved organic carbon that is more humic, as these factors are known to both increase transport of Hg to streams and its uptake in primary producers but to also decrease MeHg bioaccumulation in consumers. Overall, these results suggest that the type of disturbance from forestry affects MeHg bioaccumulation and trophic transfer in stream food webs and some longitudinal patterns along a river continuum.
Topics: Animals; Bioaccumulation; Environmental Monitoring; Fishes; Food Chain; Forests; Insecta; Mercury; Methylmercury Compounds; Water Pollutants, Chemical
PubMed: 35940481
DOI: 10.1016/j.envpol.2022.119810 -
Environmental Sciences Europe 2015Bioaccumulation plays a vital role in understanding the fate of a substance in the environment and is key to the regulation of chemicals in several jurisdictions. The... (Review)
Review
Bioaccumulation plays a vital role in understanding the fate of a substance in the environment and is key to the regulation of chemicals in several jurisdictions. The current assessment approaches commonly use the octanol-water partition coefficient (log ) as an indicator for bioaccumulation and the bioconcentration factor (BCF) as a standard criterion to identify bioaccumulative substances show limitations. The log does not take into account active transport phenomena or special structural properties (e.g., amphiphilic substances or dissociating substances) and therefore additional screening criteria are required. Regulatory BCF studies are so far restricted to fish and uptake through the gills. Studies on (terrestrial) air-breathing organisms are missing. Though there are alternative tests such as the dietary exposure bioaccumulation fish test described in the recently revised OECD test guideline 305, it still remains unclear how to deal with results of alternative tests in regulatory decision-making processes. A substantial number of bioaccumulation fish tests are required in regulation. The development of improved test systems following the 3R principles, namely to replace, reduce and refine animal testing, is thus required. All these aspects stress the importance to further develop the assessment of bioaccumulation. The Dessau Workshop on Bioaccumulation which was held from June 26th to 27th 2014, in Dessau, Germany, provided a comprehensive overview of the state of the art of bioaccumulation assessment, provided insights into the problems and challenges addressed by the regulatory authorities and described new research concepts and their regulatory implications. The event was organised by UBA (Dessau, Germany) and Fraunhofer IME (Schmallenberg, Germany). About 50 participants from industry, regulatory bodies and academia listened to 14 lectures on selected topics and joined the plenary discussions.
PubMed: 27752435
DOI: 10.1186/s12302-015-0067-0 -
Marine Environmental Research Nov 2023Bisphenol A is recognized as an endocrine disruptor that can affect several biological processes in marine species. Consequently, its use has been restricted and it has...
Bisphenol A is recognized as an endocrine disruptor that can affect several biological processes in marine species. Consequently, its use has been restricted and it has been replaced with other similar compounds named bisphenol A analogues (BPA analogues). BPA analogues are speculatively considered safer compounds than BPA and their usage is increasing with a consequent higher environmental release. In this study, specimens of the clam Ruditapes philippinarum were exposed to three main BPA analogues, namely BPAF, BPF, BPS and their mixture at an environmentally relevant concentration of 300 ng/L for 7 and 14 days. Effects on biomarkers indicative of cytotoxicity, oxidative stress and damage and neurotoxicity were evaluated. In addition, bioaccumulation of the compound tested was analysed in clam soft tissues. Results showed that BPA analogues at an environment concentration affected cellular parameters and antioxidant system causing also oxidative damage, suggesting that BPA analogues can be harmful compounds for clams.
Topics: Animals; Bioaccumulation; Oxidative Stress; Antioxidants; Bivalvia
PubMed: 37866198
DOI: 10.1016/j.marenvres.2023.106228 -
Integrated Environmental Assessment and... Sep 2021Bioaccumulation (B) assessment is challenging because there are various B-metrics from laboratory and field studies, multiple criteria and thresholds for classifying... (Review)
Review
Bioaccumulation (B) assessment is challenging because there are various B-metrics from laboratory and field studies, multiple criteria and thresholds for classifying bioaccumulative (B), very bioaccumulative (vB), and not bioaccumulative (nB) chemicals, as well as inherent variability and uncertainty in the data. These challenges can be met using a weight of evidence (WoE) approach. The Bioaccumulation Assessment Tool (BAT) provides a transparent WoE assessment framework that follows Organisation for Economic Co-operation and Development (OECD) principles for performing a WoE analysis. The BAT guides an evaluator through the process of data collection, generation, evaluation, and integration of various lines of evidence (LoE) (i.e., B-metrics) to inform decision-making. Phenanthrene (PHE) is a naturally occurring chemical for which extensive B and toxicokinetics data are available. A B assessment for PHE using the BAT is described that includes a critical evaluation of 74 measured in vivo LoE for fish and invertebrate species from laboratory and field studies. The number of LoE are reasonably well balanced across taxa (i.e., fish and invertebrates) and the different B-metrics. Additionally, in silico and in vitro biotransformation rate estimates and corresponding model-predicted B-metrics are included as corroborating evidence. Application of the BAT provides a consistent, coherent, and scientifically defensible WoE evaluation to conclude that PHE is not bioaccumulative (nB) because the overwhelming majority of the bioconcentration, bioaccumulation, and biomagnification metrics for both fish and invertebrates are below regulatory thresholds. An analysis of the relevant data using fugacity ratios is also provided, showing that PHE does not biomagnify in aquatic food webs. The critical review identifies recommendations to increase the consistency of B assessments, such as improved standardization of B testing guidelines, data reporting requirements for invertebrate studies, and consideration of temperature and salinity effects on certain B-metrics. Integr Environ Assess Manag 2021;17:911-925. © 2021 Concawe. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
Topics: Animals; Bioaccumulation; Ecotoxicology; Fishes; Food Chain; Phenanthrenes; Risk Assessment
PubMed: 33620129
DOI: 10.1002/ieam.4401 -
Scientific Reports Sep 2017Chlorinated paraffins (CPs) are highly complex technical mixtures, and the short chain chlorinated paraffins (SCCPs) are classed as persistent and have been included in...
Chlorinated paraffins (CPs) are highly complex technical mixtures, and the short chain chlorinated paraffins (SCCPs) are classed as persistent and have been included in the Stockholm Convention. However, there have been few studies of SCCPs and medium chain chlorinated paraffins (MCCPs) and their bioaccumulation and biomagnification in different species of fish. The present study investigated the levels, congener group profiles, bioaccumulation, and biomagnification of SCCPs and MCCPs in different species of fish from Liaodong Bay, North China. The ranges for the ΣSCCP and ΣMCCP concentrations were 376.3-8596 ng/g lipid weight (lw) and 22.37-5097 ng/g lw, respectively. The logarithms of bioaccumulation factors of ΣSCCPs ranged from 4.69 to 6.05, implying that SCCPs bioaccumulated in the fish. The trophic magnification factor of ΣSCCPs was 2.57, indicating that SCCPs could biomagnify in fish. Carbon chain length, the numbers of chlorine atoms, and octanol/water partition coefficients of the SCCPs and MCCPs might be important factors affecting the bioaccumulation of these chemicals in fish. The risk posed to human health by consumption of fish containing SCCPs was low. New SCCPs with nine carbons (C) were detected in fish in this study.
Topics: Animals; China; Environmental Monitoring; Fishes; Food Chain; Hydrocarbons, Chlorinated; Paraffin; Water Pollutants, Chemical
PubMed: 28883426
DOI: 10.1038/s41598-017-06148-5 -
Integrated Environmental Assessment and... May 2022Multimedia fate and transport models (MFTMs) describe how chemicals behave in the environment based on their inherent properties and the characteristics of receiving... (Review)
Review
Multimedia fate and transport models (MFTMs) describe how chemicals behave in the environment based on their inherent properties and the characteristics of receiving systems. We critically review the use of MFTMs for understanding the behavior of volatile methylsiloxanes (VMS). MFTMs have been used to predict the fate of VMS in wastewater treatment, rivers, lakes, marine systems, and the atmosphere, and to assess bioaccumulation and trophic transfers. More widely, they have been used to assess the overall persistence, long-range transport potential (LRTP), and the propensity for atmosphere-surface exchange. The application of MFTMs for VMS requires particularly careful selection of model inputs because the properties of VMS differ from those of most organic compounds. For example, although n-octanol/water partition coefficient (K ) values are high, air:water partition coefficient (K ) values are also high and n-octanol/air partition coefficient (K ) values are relatively low. In addition, organic carbon/water partition coefficient (K ) values are substantially lower than expectations based on K . This means that most empirical relationships between K and K are not appropriate. Good agreement between modeled and measured concentrations in air, sediment, and biota indicates that our understanding of environmental fate is reasonable. VMS compounds are "fliers" that principally partition to the atmosphere, implying high LRTP, although they have low redeposition potential. They are degraded in air (half-lives 3-10 days) and, thus, have low overall persistence. In water, exposure can be limited by hydrolysis, volatilization, and partitioning to sediments (where degradation half-lives are likely to be high). In food webs, they are influenced by metabolism in biota, which tends to drive trophic dilution (i.e., trophic magnification factors are often but not always <1). Key remaining uncertainties include the following: (i) the strength and direction of the temperature dependence for K ; (ii) the fate of atmospheric reaction products; and (iii) the magnitude of emissions to wastewater. Integr Environ Assess Manag 2022;18:599-621. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
Topics: 1-Octanol; Bioaccumulation; Environmental Monitoring; Multimedia; Rivers; Water
PubMed: 34375022
DOI: 10.1002/ieam.4507 -
Ecotoxicology and Environmental Safety Jul 2021Selenium (Se) is an essential microelement for human or animal health. At high concentrations, it can cause Se poisoning. Human activities (such as coal burning and...
Selenium (Se) is an essential microelement for human or animal health. At high concentrations, it can cause Se poisoning. Human activities (such as coal burning and mining) threaten soil biota by mobilizing high levels of Se. We used the earthworm Eisenia fetida as a bio-indicator of environmental pollutants to investigate Se acute toxicity, enrichment, and distribution through exposure tests using filter paper, artificial soil and cow manure. The 24 h- and 48 h-LC for the filter paper contact test were 2.7 and 1.52 μg/cm. In artificial soil test, the 14 d-LC and 14 d-biomass inhibition concentration (IC) were 63.86 and 59.81 mg/kg, respectively. The cow manure resulted in a 2.2- and 2.6-fold higher LC and IC than artificial soil results, respectively. Earthworms accumulated the largest Se load (89.47 mg/kg) in artificial soil containing 80 mg Se/kg and only accumulated 90.3 mg/kg in cow manure containing 160 mg Se/kg; 46.6-60.59% of the total Se was distributed in the tail of E. fetida. The Se enrichment rate (SER) and bioaccumulation factor (BAF) scored higher in artificial soil than in cow manure with the same Se concentration exposure, and the highest SER was 6.21 and 6.31 mg Se/kg earthworm/d, respectively. The highest BAF was 1.49 in artificial soil and 0.75 in cow manure. Our results demonstrate that selenite is more toxic to earthworms living in artificial soil than in cow manure. E. fetida possesses certain Se detoxification mechanisms by distributing Se in the tail.
Topics: Animals; Bioaccumulation; Cattle; Female; Humans; Lethal Dose 50; Manure; Oligochaeta; Selenium; Soil; Soil Pollutants
PubMed: 33915450
DOI: 10.1016/j.ecoenv.2021.112250 -
Tissue distribution and bioaccumulation of a novel polyfluoroalkyl benzenesulfonate in crucian carp.Environment International Feb 2020The emergence of novel per- and polyfluoroalkyl substances (PFASs) has enabled researchers to determine their bioaccumulation, which is important for understanding their...
The emergence of novel per- and polyfluoroalkyl substances (PFASs) has enabled researchers to determine their bioaccumulation, which is important for understanding their internal doses and environmental risks. Here, for the first time, we report on the occurrence of a novel PFAS, p-perfluorous nonenoxybenzenesulfonate (OBS) in wild crucian carp and explore its tissue distribution and bioaccumulation. The highest levels of OBS were observed in blood (mean/median: 144/133 ng/ml) with the mean tissue/blood ratios (TBRs) consistently below 1, ranging from 0.090 (muscle) to 0.644 (liver). This followed the pattern of perfluorooctane sulfonate (PFOS), implying that their distributions were similar. The calculated tissue-specific LogBAF values, except for muscle, 3.78 (gill)-4.14 (blood) over the regulatory bioaccumulation criterion (Log value: 3.70) indicated its obvious bioaccumulative potency in crucian carp. Molecular docking with estimated binding energies at -8.5 and -9.0 kcal/mol corroborated the strong interactions of OBS with human serum albumin and liver fatty acid binding protein, even though the binding energies were lower than those of PFOS. This, to some extent, explained the lower bioaccumulation of OBS than PFOS. Considering its bioaccumulative potential, large production volume, and wide use, further investigation into the environmental risk and in vivo toxicology of OBS is required.
Topics: Alkanesulfonic Acids; Animals; Benzenesulfonates; Bioaccumulation; Carps; Fluorocarbons; Humans; Molecular Docking Simulation; Tissue Distribution; Water Pollutants, Chemical
PubMed: 31881427
DOI: 10.1016/j.envint.2019.105418 -
Mycosynthesis of Metal-Containing Nanoparticles-Fungal Metal Resistance and Mechanisms of Synthesis.International Journal of Molecular... Nov 2022In the 21st century, nanomaterials play an increasingly important role in our lives with applications in many sectors, including agriculture, biomedicine, and... (Review)
Review
In the 21st century, nanomaterials play an increasingly important role in our lives with applications in many sectors, including agriculture, biomedicine, and biosensors. Over the last two decades, extensive research has been conducted to find ways to synthesise nanoparticles (NPs) via mediation with fungi or fungal extracts. Mycosynthesis can potentially be an energy-efficient, highly adjustable, environmentally benign alternative to conventional physico-chemical procedures. This review investigates the role of metal toxicity in fungi on cell growth and biochemical levels, and how their strategies of resistance, i.e., metal chelation, biomineral formation, biosorption, bioaccumulation, compartmentalisation, and efflux of metals from cells, contribute to the synthesis of metal-containing NPs used in different applications, e.g., biomedical, antimicrobial, catalytic, biosensing, and precision agriculture. The role of different synthesis conditions, including that of fungal biomolecules serving as nucleation centres or templates for NP synthesis, reducing agents, or capping agents in the synthesis process, is also discussed. The authors believe that future studies need to focus on the mechanism of NP synthesis, as well as on the influence of such conditions as pH, temperature, biomass, the concentration of the precursors, and volume of the fungal extracts on the efficiency of the mycosynthesis of NPs.
Topics: Metal Nanoparticles; Reducing Agents; Bioaccumulation; Catalysis; Biological Transport
PubMed: 36430561
DOI: 10.3390/ijms232214084 -
Ecotoxicology and Environmental Safety Sep 2022The R-package rbioacc allows to analyse experimental data from bioaccumulation tests where organisms are exposed to a chemical (exposure) then put into clean media...
The R-package rbioacc allows to analyse experimental data from bioaccumulation tests where organisms are exposed to a chemical (exposure) then put into clean media (depuration). Internal concentrations are measured over time during the experiment. rbioacc provides turnkey functions to visualise and analyse such data. Under a Bayesian framework, rbioacc fits a generic one-compartment toxicokinetic model built from the data. It provides TK parameter estimates (uptake and elimination rates) and standard bioaccumulation metrics. All parameter estimates, bioaccumulation metrics and predictions of internal concentrations are delivered with their uncertainty. Bioaccumulation metrics are provided in support of environmental risk assessment, in full compliance with regulatory requirements required to approve market release of chemical substances. This paper provides worked examples of the use of rbioacc from data collected through standard bioaccumulation tests, publicly available within the scientific literature. These examples constitute step-by-step user-guides to analyse any new data set, uploaded in the right format.
Topics: Bayes Theorem; Bioaccumulation; Toxicokinetics; Water Pollutants, Chemical
PubMed: 35843108
DOI: 10.1016/j.ecoenv.2022.113875