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1.
Environ Pollut ; 351: 123962, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38614424

ABSTRACT

Polycyclic aromatic compounds (PACs) - a large group of organic chemicals naturally present in petroleum deposits (i.e., petrogenic) or released into the environment by incomplete combustion of organic materials (i.e., pyrogenic) - represent a potential risk to the health of aquatic ecosystems. In high latitude freshwater ecosystems, concentrations of PACs may be increasing, yet there are limited studies in such systems to assess change and to understand threats. Using 10 years of contemporary data from passive samplers deployed across five regions (n = 43 sites) in the Mackenzie River Basin, we (i) describe baseline levels of PACs, (ii) assess spatiotemporal patterns, and (iii) evaluate the extent to which environmental factors (fire, snowmelt, and proximity to oil infrastructure) influence concentrations in this system. Measured concentrations were low, relative to those in more southern systems, with mixtures primarily being dominated by non-alkylated, low molecular weight compounds. Concentrations were spatially consistent, except for two sites near Norman Wells (an area of active oil extraction) with increased levels. Similarly, observed annual variation was minimal, with 2014 having generally higher levels of PACs. We did not detect effects of fire, snowmelt, or oil infrastructure on concentrations. Taken together, our findings suggest that PACs in the Mackenzie River are currently at low levels and are primarily petrogenic in origin. They further indicate that ongoing monitoring and testing of environmental drivers (especially at finer spatial scales) are needed to better predict how ecosystem change will influence PAC levels in the basin and in other northern systems.


Subject(s)
Ecosystem , Environmental Monitoring , Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Rivers/chemistry , Fresh Water/chemistry
2.
Environ Toxicol Chem ; 43(5): 988-998, 2024 May.
Article in English | MEDLINE | ID: mdl-38415966

ABSTRACT

Anticoagulant rodenticides (ARs) have caused widespread contamination and poisoning of predators and scavengers. The diagnosis of toxicity proceeds from evidence of hemorrhage, and subsequent detection of residues in liver. Many factors confound the assessment of AR poisoning, particularly exposure dose, timing and frequency of exposure, and individual and taxon-specific variables. There is a need, therefore, for better AR toxicity criteria. To respond, we compiled a database of second-generation anticoagulant rodenticide (SGAR) residues in liver and postmortem evaluations of 951 terrestrial raptor carcasses from Canada and the United States, 1989 to 2021. We developed mixed-effects logistic regression models to produce specific probability curves of the toxicity of ∑SGARs at the taxonomic level of the family, and separately for three SGARs registered in North America, brodifacoum, bromadiolone, and difethialone. The ∑SGAR threshold concentrations for diagnosis of coagulopathy at 0.20 probability of risk were highest for strigid owls (15 ng g-1) lower and relatively similar for accipitrid hawks and eagles (8.2 ng g-1) and falcons (7.9 ng g-1), and much lower for tytonid barn owls (0.32 ng g-1). These values are lower than those we found previously, due to compilation and use of a larger database with a mix of species and source locations, and also to refinements in the statistical methods. Our presentation of results on the family taxonomic level should aid in the global applicability of the numbers. We also collated a subset of 440 single-compound exposure events and determined the probability of SGAR-poisoning symptoms as a function of SGAR concentration, which we then used to estimate relative SGAR toxicity and toxic equivalence factors: difethialone, 1, brodifacoum, 0.8, and bromadiolone, 0.5. Environ Toxicol Chem 2024;43:988-998. © 2024 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC Reproduced with the permission of the Minister of Environment and Climate Change Canada.


Subject(s)
Anticoagulants , Raptors , Rodenticides , Rodenticides/toxicity , Animals , Anticoagulants/toxicity , Anticoagulants/poisoning , 4-Hydroxycoumarins/poisoning , 4-Hydroxycoumarins/toxicity , Canada , Environmental Monitoring
3.
J Chromatogr A ; 1718: 464723, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38341899

ABSTRACT

The scientific literature is replete with analytical methods for the analysis of homocyclic aromatic compounds especially polycyclic aromatic hydrocarbons and their alkylated analogs. However, there is a paucity of methods for the analysis of nitrogen-, sulfur- and oxygen-containing polycyclic aromatic compounds (PACs). The lack of commercially available analytical standards, the presence of many structural derivatives and isomers and lack of certified reference materials all contribute to the inherent challenges in measuring these compounds. Gas chromatography coupled with a tandem mass spectrometer was used to develop two multiple reaction monitoring methods to detect and quantify fifty-three non-halogenated and halogenated hetero-polycyclic aromatic compounds (HPACs). Because of their greater polarity, strongly non-polar solvents typically employed to extract homocyclic PACs from sediment samples did not yield acceptable recoveries of our target analytes. By adding ethyl acetate to dichloromethane (50:50), recoveries of our target analytes using accelerated solvent extraction increased markedly. The performance characteristics of the validated method including accuracy [> than 67% for 46 (out of 53) analytes], inter- and intra-day precision [<30% for all analytes, (expressed as relative standard deviation)], limits of detection (0.1 to 2.3 ng/g) and quantitation (1.5 to 7.6 ng/g) imply that the method is fit for its intended purpose. A sediment sample from a known contaminated site in Canada was analyzed for both homo- and hetero-PACs. Measured concentrations of Σ27HPAC (7.3 µg/g, dry weight) were significantly smaller (p<0.05) than Σ16PAHs (80.9 µg/g, dry weight) and Σ30Alkylated-PAHs (14.2 µg/g, dry weight). These results suggest that the developed method is an effective and efficient approach for the targeted analysis of HPACs and their halogenated derivatives in sediment samples.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Polycyclic Compounds , Gas Chromatography-Mass Spectrometry/methods , Mass Spectrometry , Polycyclic Aromatic Hydrocarbons/analysis , Chromatography, Gas
4.
Front Oncol ; 13: 1224347, 2023.
Article in English | MEDLINE | ID: mdl-37860189

ABSTRACT

Background: For therapy planning in cancer patients multidisciplinary team meetings (MDM) are mandatory. Due to the high number of cases being discussed and significant workload of clinicians, Clinical Decision Support System (CDSS) may improve the clinical workflow. Methods: This review and meta-analysis aims to provide an overview of the systems utilized and evaluate the correlation between a CDSS and MDM. Results: A total of 31 studies were identified for final analysis. Analysis of different cancers shows a concordance rate (CR) of 72.7% for stage I-II and 73.4% for III-IV. For breast carcinoma, CR for stage I-II was 72.8% and for III-IV 84.1%, P≤ 0.00001. CR for colorectal carcinoma is 63% for stage I-II and 67% for III-IV, for gastric carcinoma 55% and 45%, and for lung carcinoma 85% and 83% respectively, all P>0.05. Analysis of SCLC and NSCLC yields a CR of 94,3% and 82,7%, P=0.004 and for adenocarcinoma and squamous cell carcinoma in lung cancer a CR of 90% and 86%, P=0.02. Conclusion: CDSS has already been implemented in clinical practice, and while the findings suggest that its use is feasible for some cancers, further research is needed to fully evaluate its effectiveness.

5.
Soins Gerontol ; 28(163): 27-29, 2023.
Article in French | MEDLINE | ID: mdl-37716778

ABSTRACT

The use of psychotropic drugs in the elderly is frequent, and can be problematic due to the risks associated with their inappropriate use and adverse effects. It is essential to adopt a cautious, individualized approach to prescribing psychotropic drugs, regularly assessing their efficacy and considering other non-drug approaches where possible. Collaboration between healthcare professionals and patients can contribute to more appropriate use of these drugs in the elderly.


Subject(s)
Drug Prescriptions , Psychotropic Drugs , Humans , Aged , Psychotropic Drugs/adverse effects , Health Personnel , Inappropriate Prescribing
6.
Trials ; 24(1): 577, 2023 Sep 09.
Article in English | MEDLINE | ID: mdl-37684688

ABSTRACT

INTRODUCTION: Multidisciplinary team meetings (MDMs), also known as tumor conferences, are a cornerstone of cancer treatments. However, barriers such as incomplete patient information or logistical challenges can postpone tumor board decisions and delay patient treatment, potentially affecting clinical outcomes. Therapeutic Assistance and Decision algorithms for hepatobiliary tumor Boards (ADBoard) aims to reduce this delay by providing automated data extraction and high-quality, evidence-based treatment recommendations. METHODS AND ANALYSIS: With the help of natural language processing, relevant patient information will be automatically extracted from electronic medical records and used to complete a classic tumor conference protocol. A machine learning model is trained on retrospective MDM data and clinical guidelines to recommend treatment options for patients in our inclusion criteria. Study participants will be randomized to either MDM with ADBoard (Arm A: MDM-AB) or conventional MDM (Arm B: MDM-C). The concordance of recommendations of both groups will be compared using interrater reliability. We hypothesize that the therapy recommendations of ADBoard would be in high agreement with those of the MDM-C, with a Cohen's kappa value of ≥ 0.75. Furthermore, our secondary hypotheses state that the completeness of patient information presented in MDM is higher when using ADBoard than without, and the explainability of tumor board protocols in MDM-AB is higher compared to MDM-C as measured by the System Causability Scale. DISCUSSION: The implementation of ADBoard aims to improve the quality and completeness of the data required for MDM decision-making and to propose therapeutic recommendations that consider current medical evidence and guidelines in a transparent and reproducible manner. ETHICS AND DISSEMINATION: The project was approved by the Ethics Committee of the Charité - Universitätsmedizin Berlin. REGISTRATION DETAILS: The study was registered on ClinicalTrials.gov (trial identifying number: NCT05681949; https://clinicaltrials.gov/study/NCT05681949 ) on 12 January 2023.


Subject(s)
Liver Neoplasms , Humans , Reproducibility of Results , Retrospective Studies , Liver Neoplasms/diagnosis , Liver Neoplasms/therapy , Algorithms , Patient Care Team , Randomized Controlled Trials as Topic
7.
Molecules ; 28(13)2023 Jun 24.
Article in English | MEDLINE | ID: mdl-37446635

ABSTRACT

Caffeic acid (CA) exhibits a myriad of biological activities including cardioprotective action, antioxidant, antitumor, anti-inflammatory, and antimicrobial properties. On the other hand, CA presents low water solubility and poor bioavailability, which have limited its use for therapeutic applications. The objective of this study was to develop a nanohybrid of zinc basic salts (ZBS) and chitosan (Ch) containing CA (ZBS-CA/Ch) and evaluate its anti-edematogenic and antioxidant activity in dextran and carrageenan-induced paw edema model. The samples were obtained by coprecipitation method and characterized by X-ray diffraction, Fourier transform infrared (FT-IR), scanning electron microscope (SEM) and UV-visible spectroscopy. The release of caffeate anions from ZBS-CA and ZBS-CA/Ch is pH-dependent and is explained by a pseudo-second order kinetics model, with a linear correlation coefficient of R2 ≥ 0.99 at pH 4.8 and 7.4. The in vivo pharmacological assays showed excellent anti-edematogenic and antioxidant action of the ZBS-CA/Ch nanoparticle with slowly releases of caffeate anions in the tissue, leading to a prolongation of CA-induced anti-edematogenic and anti-inflammatory activities, as well as improving its inhibition or sequestration antioxidant action toward reactive species. Overall, this study highlighted the importance of ZBS-CA/Ch as an optimal drug carrier.


Subject(s)
Chitosan , Humans , Chitosan/chemistry , Delayed-Action Preparations/chemistry , Spectroscopy, Fourier Transform Infrared , Antioxidants/pharmacology , Anti-Inflammatory Agents/pharmacology , Edema/pathology , Zinc/chemistry
8.
Chemosphere ; 335: 139059, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37268236

ABSTRACT

Due to their relatively high trophic position and importance as a food source for many communities in the circumpolar north, seabird eggs are an important matrix for monitoring contaminant levels. In fact, many countries, including Canada, have established long-term seabird egg contaminant monitoring programs, with oil related compounds a contaminant of emerging concern for seabirds in several regions. Current approaches to measuring many contaminant burdens in seabird eggs are time-consuming and often require large volumes of solvent. Here we propose an alternative approach, based on the principle of microbead beating tissue extraction using custom designed stainless-steel extraction tubes and lids, to measure a suite of 75 polycyclic aromatic compounds (polycyclic aromatic hydrocarbons (PAHs), alkyl-PAHs, halogenated-PAHs and some heterocyclic compounds) comprising a wide-range of chemical properties. Our method was conducted in strict accordance with ISO/IEC 17025 guidelines for method validation. Accuracies for our analytes generally ranged from 70 - 120%, and intra and inter-day repeatability for most analytes were < 30%. Limits of detection/quantitation for the 75 target analytes were < 0.2/0.6 ng g-1. The level of contamination in our method blanks was significantly smaller in our stainless-steel tubes/lids relative to commercially available high-density plastic alternatives. Overall, our method meets our data quality objectives and results in a notable reduction in sample processing times relative to current approaches.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Polycyclic Compounds , Microspheres , Polycyclic Aromatic Hydrocarbons/chemistry , Solvents , Steel
9.
Opt Express ; 31(10): 15316-15325, 2023 May 08.
Article in English | MEDLINE | ID: mdl-37157635

ABSTRACT

We report on the development of all-fiber stand-alone iodine-filled photonic microcells demonstrating record absorption contrast at room temperature. The microcell's fiber is made of inhibited coupling guiding hollow-core photonic crystal fibers. The fiber-core loading with iodine was undertaken at 10-1-10-2mbar vapor pressure using what, to the best of our knowledge, is a novel gas-manifold based on metallic vacuum parts with ceramic coated inner surfaces for corrosion resistance. The fiber is then sealed on the tips and mounted on FC/APC connectors for better integration with standard fiber components. The stand-alone microcells display Doppler lines with contrasts up to 73% in the 633 nm wavelength range, and an off-resonance insertion loss between 3 to 4 dB. Sub-Doppler spectroscopy based on saturable absorption has been carried out to resolve the hyperfine structure of the P(33)6-3 lines at room temperature with a full-width at half maximum of 24 MHz on the b4 component with the help of lock-in amplification. Also, we demonstrate distinguishable hyperfine components on the R(39)6-3 line at room temperature without any recourse to signal-to-noise ratio amplification techniques.

10.
Chemosphere ; 333: 138802, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37146778

ABSTRACT

The present study was aimed at identifying geospatial patterns of pollutants including concentrations and toxicity as complex environmental mixtures, in topsoil samples close to petrochemical facilities in the heavily industrialized area of Augusta and Priolo in south-eastern Sicily (Italy). Elemental analysis of soil was conducted by ICP-MS for 23 metals and 16 rare earth elements (REEs). Organic analyses were primarily focused on polycyclic aromatic hydrocarbons (PAHs) (16 parent homologs) and total aliphatic hydrocarbons (C10 - C40). Topsoil samples were tested for toxicity in multiple bioassay models including: 1) developmental defects and cytogenetic anomalies in sea urchin Sphaerechinus granularis early life stages; 2) growth inhibition of diatom Phaeodactylum tricornutum; 3) mortality in nematode Caenorhabditis elegans; and 4) induction of mitotic abnormalities in onion Allium cepa. Samples collected at sites closest to defined petrochemical facilities were highest in select pollutants and correlated with biological effects in different toxicity endpoints. A noteworthy finding was the increased level of total REEs in sites closest to petrochemical facilities, suggesting their contributions to identifying petrochemical sources of pollutants to the environment. The combined data obtained in the different bioassays allowed exploration of geospatial patterns of effect in biota as a function of contaminant levels. In conclusion, this study provides consistent data of soil toxicity, metal and REE contamination at Augusta-Priolo sampling sites, and may provide an appropriate baseline for epidemiological studies on high incidences of congenital birth defects in the area and identification of at-risk localities.


Subject(s)
Environmental Pollutants , Metals, Rare Earth , Polycyclic Aromatic Hydrocarbons , Soil Pollutants , Animals , Sicily , Environmental Pollution/analysis , Sea Urchins , Metals/analysis , Environmental Pollutants/analysis , Metals, Rare Earth/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Soil , Environmental Monitoring , Soil Pollutants/analysis
11.
Bull Environ Contam Toxicol ; 110(3): 65, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36922429

ABSTRACT

Rare earth elements (REEs) cerium (Ce) and lanthanum (La) and their combination were tested across a concentration range, from toxic (10-4 to 10-5 M) to lower concentrations (10-6 to 10-8 M) for their effects on sea urchin (Sphaerechinus granularis) sperm. A significantly decreased fertilization rate (FR) was found for sperm exposed to 10-5 M Ce, La and their combination, opposed to a significant increase of FR following 10-7 and 10-8 M REE sperm exposure. The offspring of REE-exposed sperm showed significantly increased developmental defects following sperm exposure to 10-5 M REEs vs. untreated controls, while exposure to 10-7 and 10-8 M REEs resulted in significantly decreased rates of developmental defects. Both of observed effects-on sperm fertilization success and on offspring quality-were closely exerted by Ce or La or their combination.


Subject(s)
Cerium , Metals, Rare Earth , Animals , Male , Lanthanum/toxicity , Cerium/toxicity , Semen , Sea Urchins , Metals, Rare Earth/toxicity , Spermatozoa
12.
Biol Trace Elem Res ; 201(5): 2573-2581, 2023 May.
Article in English | MEDLINE | ID: mdl-35715718

ABSTRACT

Rare earth elements (REEs) are recognized as emerging contaminants with implications in human and environmental health. Apart from their adverse effects, REEs have been reported as having positive effects when amended to fertilizers and livestock feed additives, thus suggesting a hormetic trend, implying a concentration-related shift from stimulation to inhibition and toxicity, with analogous trends that have been assessed for a number of xenobiotics. In view of optimizing the success of REE mixtures in stimulating crop yield and/or livestock growth or egg production, one should foresee the comparative concentration-related effects of individual REEs (e.g., Ce and La) vs. their mixtures, which may display distinct trends. The results might prompt further explorations on the use of REE mixtures vs. single REEs aimed at optimizing the preparation of fertilizers and feed additives, in view of the potential recognition of their use in agronomy and zootechny.


Subject(s)
Fertilizers , Metals, Rare Earth , Animals , Humans , Livestock , Metals, Rare Earth/toxicity , Agriculture , Animal Feed
13.
Soins Gerontol ; 27(158): 30-32, 2022.
Article in French | MEDLINE | ID: mdl-36503662

ABSTRACT

In recent years, a number of actions have been carried out to develop assistance for caregivers in France. This assistance can be coordinated with the help of social services, which can be difficult for both the elderly person and their caregiver, for psychological reasons. If an adapted and rehabilitated care pathway is not put in place, the caregiver may be exposed to psychosocial risks.


Subject(s)
Caregivers , Critical Pathways , Humans , Aged , Caregivers/psychology , France
14.
Soins Gerontol ; 27(158): 27-29, 2022.
Article in French | MEDLINE | ID: mdl-36503661

ABSTRACT

Depression in the elderly is difficult to identify because it is often masked by other pathological features. It is therefore important for everyone involved to be vigilant and to be able to ask for help from a qualified professional. The individual interacts with his or her human and material environment. The environment can be depressogenic. The quality of life of the person intervenes in the course of the depression.


Subject(s)
Quality of Life , Male , Female , Humans , Aged
15.
Soins Gerontol ; 27(158): 9-33, 2022.
Article in French | MEDLINE | ID: mdl-36503667
16.
Environ Monit Assess ; 194(10): 670, 2022 Aug 16.
Article in English | MEDLINE | ID: mdl-35970905

ABSTRACT

River otters (Lontra canadensis) are apex predators that bioaccumulate contaminants via their diet, potentially serving as biomonitors of watershed health. They reside throughout the Green-Duwamish River, WA (USA), a watershed encompassing an extreme urbanization gradient, including a US Superfund site slated for a 17-year remediation. The objectives of this study were to document baseline contaminant levels in river otters, assess otters' utility as top trophic-level biomonitors of contaminant exposure, and evaluate the potential for health impacts on this species. We measured a suite of contaminants of concern, lipid content, nitrogen stable isotopes (δ15N), and microsatellite DNA markers in 69 otter scat samples collected from twelve sites. Landcover characteristics were used to group sampling sites into industrial (Superfund site), suburban, and rural development zones. Concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ether flame-retardants (PBDEs), dichlorodiphenyl-trichloroethane and its metabolites (DDTs), and polycyclic aromatic hydrocarbons (PAHs) increased significantly with increasing urbanization, and were best predicted by models that included development zone, suggesting that river otters are effective biomonitors, as defined in this study. Diet also played an important role, with lipid content, δ15N or both included in all best models. We recommend river otter scat be included in evaluating restoration efforts in this Superfund site, and as a potentially useful monitoring tool wherever otters are found. We also report ΣPCB and ΣPAH exposures among the highest published for wild river otters, with almost 70% of samples in the Superfund site exceeding established levels of concern.


Subject(s)
Environmental Pollutants , Otters , Water Pollutants, Chemical , Animals , Environmental Monitoring , Environmental Pollutants/metabolism , Halogenated Diphenyl Ethers/analysis , Lipids , Water Pollutants, Chemical/analysis
17.
Soins Gerontol ; 27(156): 13-22, 2022.
Article in French | MEDLINE | ID: mdl-35926968

ABSTRACT

The sexual life of elderly people living in residential institutions for the dependent elderly (Ehpad) is a sensitive subject that is rarely discussed. Particular difficulties sometimes arise when they have cognitive problems. Affectivity and sexuality in old people's homes must be approached with tact and maturity by the carers. Sexuality belongs to private life, but its excesses are difficult to reconcile with collective life. Some proposals can be made on ethical issues and on the relationship with residents and their families.


Subject(s)
Sexual Behavior , Sexuality , Aged , Emotions , Humans , Sexuality/psychology
18.
Soins Gerontol ; 27(156): 27-32, 2022.
Article in French | MEDLINE | ID: mdl-35926970

ABSTRACT

Taking into account the needs and expectations of families in residential care facilities for the dependent elderly (Ehpad) leads to their satisfaction with the care given to their institutionalized relative. A relational charter participate to prevent conflicts and misunderstandings between the various formal (caregivers) and informal (families) care providers at the bedside of residents. Families must feel invited to the Ehpad and recognized in their place in their role of care, at least relational. Some families, however, remain firmly anchored in an irrefragable hostility. Solidarity in the teams and the robustness of the care project are essential here.


Subject(s)
Caregivers , Family , Motivation , Aged , Humans , Residential Facilities
19.
J Appl Toxicol ; 42(12): 2005-2015, 2022 12.
Article in English | MEDLINE | ID: mdl-35894097

ABSTRACT

The extraction of bitumen from surface mining in the Athabasca Oil Sands Region (AOSR) produces large quantities of oil sands process-affected water (OSPW) that needs to be stored in settling basins near extraction sites. Chemical constituents of OSPW are known to impair bone health in some organisms, which can lead to increased fracture risk and lower reproductive fitness. Naphthenic acid fraction components (NAFCs) are thought to be among the most toxic class of compounds in OSPW; however, the effect of NAFCs on osteoblast development is largely unknown. In this study, we demonstrate that NAFCs from OSPW inhibit osteoblast differentiation and deposition of extracellular matrix, which is required for bone formation. Extracellular matrix deposition was inhibited in osteoblasts exposed to 12.5-125 mg/L of NAFC for 21 days. We also show that components within NAFCs inhibit the expression of gene markers of osteoblast differentiation and function, namely, alkaline phosphatase (Alp), osteocalcin, and collagen type 1 alpha 1 (Col1a1). These effects were partially mediated by the induction of glucocorticoid receptor (GR) activity; NAFC induces the expression of the GR activity marker genes Sgk1 (12.5 mg/L) and p85a (125 mg/L) and inhibits GR protein (125 mg/L) and Opg RNA (12.5 mg/L) expression. This study provides evidence that NAFC concentrations of 12.5 mg/L and above can directly act on osteoblasts to inhibit bone formation and suggests that NAFCs contain components that can act as GR agonists, which may have further endocrine disrupting effects on exposed wildlife.


Subject(s)
Oil and Gas Fields , Water Pollutants, Chemical , Animals , Mice , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Osteogenesis , Carboxylic Acids/chemistry , Water/chemistry , Osteoblasts
20.
Aquat Toxicol ; 250: 106248, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35905632

ABSTRACT

The contamination of lakes by industrial emissions is an issue of international concern. Traditional paleolimnology examines sedimentary micro-fossils to infer the biological response to natural and anthropogenic stressors over time. Here, we calculate a theoretical biological effect for historic sediment sections using Probable Effect Concentration Quotient (PEC-Q) and arsenic specific quotient methods and develop novel time-constrained sediment toxicity test methods using a cultured Daphnia sp. combined with a whole cell microbial biosensor to assess the toxicity of past industrial contamination with modern testing methods. These methods were developed using sediments collected from Pocket Lake (Northwest Territories, Canada), a lake known to have exhibited a significant ecological shift following input from nearby gold smelter emissions during the mid 20th century. We then applied these methods to near-, mid-, and far-field sites to assess the response of Daphnia sp. to varying contaminant load. Daphnia sp. mortality exposed to dated sediments indicated a strong concordance with the timing of mining activities, and a strong concordance with PEC-Q and arsenic specific toxicity quotients. In contrast, a decrease in Daphnia mortality was observed during pre-, and post-mining periods when the contaminant burden was lower. Initial assessments of bioavailability using a microbial biosensor indicated that arsenic in porewater is 72-96% bioavailable, and limited evidence that oxidative stress may contribute to the Daphnia sp. toxic response. These results indicate that lake sediment archives can be used to infer missing biomonitoring data in sites of legacy anthropogenic influence, which will be useful for those seeking to conduct cost-effective and efficient preliminary environmental risk assessments.


Subject(s)
Arsenic , Geologic Sediments , Mining , Water Pollutants, Chemical , Animals , Arsenic/toxicity , Daphnia , Environmental Monitoring/methods , Geologic Sediments/chemistry , Gold , Lakes , Water Pollutants, Chemical/toxicity
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