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The toxicity of intact sediments and sediment extracts, from both an uncontaminated site and a site contaminated by pulp-mill effluents, was tested in a five months study. The deposit-feeding amphipod Monoporeia affinis was exposed in soft-bottom flow-through water microcosms. To examine potential toxicity a set of reproduction endpoints was used including fecundity and different embryo aberrations such as malformed eggs. Among extracts, the aliphatic/monoaromatic and diaromatic fractions along with the total extract were shown to cause the highest toxicity measured as malformed eggs, while the polyaromatic fraction caused toxicity at background levels. A comparison between sediment extracts and pulp mill contaminated intact sediment, however, showed no toxicity of the intact sediment. Thus, the extraction procedure seems to increase bioavailability and subsequently toxicity as compared to the intact sediments in situ. In toxicity testing using fractionated extracts of sediments in a toxicity identification evaluation (TIE) procedures, caution should therefore be taken when assessing bioavailable contaminants in contaminated areas. This should be taken in account both in determining remediation priorities as well as in ecological risk assessments.
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http://dx.doi.org/10.1016/j.marpolbul.2005.02.030 | DOI Listing |
Biology (Basel)
August 2025
State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China.
Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are promising molecular biomarkers widely applied in paleoenvironmental reconstructions, including temperature and pH. However, knowledge of the microorganisms responsible for brGDGT production in marine environments remains limited, which constrains the further development and application of brGDGT-based proxies for reconstructing past marine conditions. In this study, both 'living' intact polar lipid-derived brGDGTs (IPL-brGDGTs) and 'fossil' core brGDGTs (CL-brGDGTs), together with bacterial community compositions, were analysed in multiple sediment cores collected along a nearshore-to-offshore transect in the East China Sea (ECS).
View Article and Find Full Text PDFTop Companion Anim Med
September 2025
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, 300 West Drake Road, Fort Collins CO 80523. Electronic address:
A 4-year-old, 0.81 kg, female intact, American guinea pig (Cavia porcellus) was presented for a one-day history of perianal swelling. Physical examination revealed a body condition score of 2 out of 9, a distended abdomen that was painful on palpation, an abnormal vulvar conformation that was enlarged, edematous, ulcerated, and erythematous with adhered foreign material, and a 1 × 1 cm firm mass of the right mammary gland.
View Article and Find Full Text PDFRapid Commun Mass Spectrom
November 2025
MARUM - Center for Marine Environmental Sciences, and Faculty of Geosciences, University of Bremen, Bremen, Germany.
Rationale: The stable carbon isotopic composition (δC) of individual lipids is of great value in studying carbon cycling. Among those, microbial lipids in sediments impacted by high methane turnover stand out due to their uniquely depleted isotopic fingerprint. However, gas chromatography/isotope ratio mass spectrometry (GC/irMS) is limited to volatile compounds, whereas intact polar lipids require extensive preprocessing, which results in the loss of chemotaxonomic information.
View Article and Find Full Text PDFToxicol Res (Camb)
August 2025
Center of Experimental Teaching for Public Health, Experimental Teaching and Management Center, Chongqing Medical University, No. 1, Yixueyuan Road, Yuzhong District, Chongqing 400016, People's Republic of China.
Cadmium (Cd), a well-known environmental pollutant, widely exists in water, soils, sediments, and air, and produces various system dysfunctions including those affecting the nervous system. L-carnitine (L-CAR) is an antioxidant that plays neuroprotective roles by improving enzyme functions. The purpose of our study was to evaluate whether L-CAR could efficiently protest against neurotoxicity induced by Cd.
View Article and Find Full Text PDFBull Environ Contam Toxicol
July 2025
Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, N9B 3P4, Canada.
The sediment equilibrium phosphorus concentration (EPC) is used to estimate phosphorus (P) flux at the sediment-water interface. This parameter is most commonly measured by the batch method which potentially disrupts natural sediment structure at sampling. This manuscript describes the use of a dynamic mesocosm system consisting of sediment cores modified to recirculate overlying waters from the cores through an external reservoir that is subject to experimental manipulation.
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