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Chronic exposure to copper and zinc induces DNA damage in the polychaete Alitta virens and the implications for future toxicity of coastal sites Full text
2018
Watson, G. J. | Pini, J. M. | Richir, Jonathan | Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth
peer reviewed | Copper and zinc are metals that have been traditionally thought of as past contamination legacies. However, their industrial use is still extensive and current applications (e.g. nanoparticles and antifouling paints) have become additional marine environment delivery routes. Determining a pollutant's genotoxicity is an ecotoxicological priority, but in marine benthic systems putative substances responsible for sediment genotoxicity have rarely been identified. Studies that use sediment as the delivery matrix combined with exposures over life-history relevant timescales are also missing for metals. Here we assess copper and zinc's genotoxicity by exposing the ecologically important polychaete Alitta virens to sediment spiked with environmentally relevant concentrations for 9 months. Target bioavailable sediment and subsequent porewater concentrations reflect the global contamination range for coasts, whilst tissue concentrations, although elevated, were comparable with other polychaetes. Survival generally reduced as concentrations increased, but monthly analyses show that growth was not significantly different between treatments. The differential treatment mortality may have enabled the surviving worms in the high concentration treatments to capture more food thus removing any concentration treatment effects for biomass. Using the alkaline comet assay we confirm that both metals via the sediment are genotoxic at concentrations routinely found in coastal regions and this is supported by elevated DNA damage in worms from field sites. However, combined with the growth data it also highlights the tolerance of A. virens to DNA damage. Finally, using long term (decadal) monitoring data we show stable or increasing sediment concentrations of these metals for many areas. This will potentially mean coastal sediment is a significant mutagenic hazard to the benthic community for decades to come. An urgent reappraisal of the current input sources for these ‘old pollutants’ is, therefore, required. Chronic exposure of zinc and copper via sediment at environmentally relevant concentrations induces DNA damage in a marine polychaete. © 2018 Elsevier Ltd
Show more [+] Less [-]Organic fertilizer activates soil beneficial microorganisms to promote strawberry growth and soil health after fumigation Full text
2022
Li, Q. | Zhang, D. | Song, Zhaoxin | Ren, L. | Jin, X. | Fang, W. | Yan, D. | Li, Yuan | Wang, Q. | Cao, A.
peer reviewed | Soil fumigants aim to control soil-borne diseases below levels that affect economic crop production, but their use also reduces the abundance of beneficial microorganisms. Previous studies have shown that adding various types of fertilizers to soil after fumigation can reshape the soil microbial community and regulate crop growth. We fumigated soil with dazomet (DZ) that had been cropped continuously for more than 20 years. After fumigation we applied silicon fertilizer, potassium humate organic fertilizer, Bacillus microbial fertilizer or a mixture of the last two. We studied the effects of different fertilizers treatments on the soil's physicochemical properties, enzyme activities, key soil pathogens and beneficial microbes. We found that fertilizers applied after fumigation promoted soil beneficial microorganisms (such as Fimicutes, Chloroflexi, Bacillus and Actinomadura) restoration; increased Fusarium and Phytophthora pathogen mortality, the content of ammonium nitrogen, sucrase enzyme activity; and increased strawberry fruit yield. A significant increase in strawberry yield was positively correlated with increases in beneficial microorganisms such as Gemmatimonadota, Firmicutes, Bacillus and Flavisolibacter. We concluded that organic fertilizer applied after fumigation significantly increased the number of beneficial microorganisms, improved the physicochemical properties of the soil, increased soil enzyme activities, inhibited the growth of soil pathogens to increase strawberry fruit yield. In summary, organic fertilizer activated soil beneficial microorganisms after soil fumigation, promoted soil health, and increased strawberry fruit yield. © 2021
Show more [+] Less [-]Targeting the right parameters in PAH remediation studies Full text
2021
Davin, Marie | Colinet, Gilles | Fauconnier, Marie-Laure
peer reviewed | Contaminated land burdens the economy of many countries and must be dealt with. Researchers have published thousands of documents studying and developing soil and sediment remediation treatments. Amongst the targeted pollutants are the polycyclic aromatic hydrocarbons (PAHs), described as a class of persistent organic compounds, potentially harmful to ecosystems and living organisms. The present paper reviews and discusses three scientific trends that are leading current PAH-contaminated soil/sediment remediation studies and management. First, the choice of compounds that are being studied and targeted in the scientific literature is discussed, and we suggest that the classical 16 US-EPA PAH compounds might no longer be sufficient to meet current environmental challenges. Second, we discuss the choice of experimental material in remediation studies. Using bibliometric measures, we show the lack of PAH remediation trials based on co-contaminated or aged-contaminated material. Finally, the systematic use of the recently validated bioavailability measurement protocol (ISO/TS 16751) in remediation trials is discussed, and we suggest it should be implemented as a tool to improve remediation processes and management strategies.
Show more [+] Less [-]Trace metal and stable isotope measurements (delta C-13 and delta N-15) in the harbour porpoise Phocoena phocoena relicta from the Black Sea Full text
2004
Das, Krishna | Holsbeek, Ludo | Browning, Julie | Siebert, Ursula | Birkun, Alexei | Bouquegneau, Jean-Marie | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Stable carbon and nitrogen isotopes (delta(13)C and delta(15)N) and trace metals (Cd, Zn, Cu, Fe, Se, and Hg) were analysed in the tissues of 46 harbour porpoises (Phocoena phocoena relicta) caught in fishing nets along the Ukrainian coasts between 1997 and 1998. Mean delta(13)C values differed significantly between male and female harbour porpoises suggesting a trophic segregation between sexes with a more coastal distribution for females at least during their gestation and nursing periods. Hepatic Hg was correlated to delta(13)C measurements, reflecting a different exposure linked to coastal vs offshore feeding habitats. A geographical comparison with existing data from other regions showed general low levels of Hg, Cd, Cu and Zn in the tissues of harbour porpoises from the Black Sea compared to other Atlantic and North Sea areas. (C) 2004 Elsevier Ltd. All rights reserved.
Show more [+] Less [-]Effects of grassed buffer strip management on potential denitrification in a belgian agricultural watershed Full text
2003
Cors, Marie | Tychon, Bernard
Riparian buffer strips are managed for the enhancement of water quality through control of non point source pollution. Denitrification in riparian buffer strips is thought to be the major process -with nitrate uptake by plant growth- that reduces nitrate input in surface water. We investigated the Denitrifier Enzyme Activity (DEA) to test how the buffer strip management modifies the denitrification process. The experimental site is composed of a crop field and a 11 m wide grassed buffer strip at the border between the crop field and a tributary to the Attert river, South-East Belgium. Soil samples from the crop field and the buffer strip have been submitted to different imposed conditions combining glucose, nitrate and water saturation to investigate how antecedent water regime, nitrate and carbon content affect denitrification. The work included DEA measurements on undisturbed soil cores freshly sampled. Experiments on undisturbed soil cores identify the buffer strip as more effective in denitrification (p < 0.001) than the cropped field. However, experiments on samples conditioned under imposed carbon and/or nitrate contents emphasised the importance of micro-topography.
Show more [+] Less [-]In vitro differential responses of rat and human aryl hydrocarbon receptor to two distinct ligands and to different polyphenols Full text
2020
Doan, Thi-Que | Connolly, L. | Igout, Ahmed | Muller, Marc | Scippo, Marie-Louise | FARAH - Fundamental and Applied Research for Animals and Health - ULiège | GIGA‐R - Giga‐Research - ULiège
In vitro differential responses of rat and human aryl hydrocarbon receptor to two distinct ligands and to different polyphenols Full text
2020
Doan, Thi-Que | Connolly, L. | Igout, Ahmed | Muller, Marc | Scippo, Marie-Louise | FARAH - Fundamental and Applied Research for Animals and Health - ULiège | GIGA‐R - Giga‐Research - ULiège
peer reviewed | Protected
Show more [+] Less [-]In vitro differential responses of rat and human aryl hydrocarbon receptor to two distinct ligands and to different polyphenols Full text
2020
Doan, T.Q. | Connolly, L. | Igout, A. | Müller, M. | Scippo, M.L.
TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) and several other environment/food-borne toxic compounds induce their toxicity via the aryl hydrocarbon receptor (AhR). AhR is also modulated by various endogenous ligands e.g. highly potent tryptophan (Trp)-derivative FICZ (6-formylindolo[3,2-b]carbazole) and natural ligands abundant in the human diet e.g. polyphenols. Therefore, evaluating AhR species-specific responses is crucial for understanding AhR physiological functions, establishing risk assessments, and exploring the applicability of AhR mediators in drug and food industry towards human-based usages. We studied AhR transactivation of FICZ/TCDD in vitro in a time-dependent and species-specific manner using dioxin responsive luciferase reporter gene assays derived from rat (DR-H4IIE) and human (DR-HepG2) hepatoma cells. We observed for the first time that FICZ potency was similar in both cell lines and was 40 times higher than TCDD in DR-HepG2 cells. Depleting Trp-derivative endogenously produced ligands by using culture medium without Trp, resulted in 3-fold higher AhR activation upon adding FICZ in DR-H4IIE cells, in contrast to DR-HepG2 cells which revealed a fast degradation of FICZ induction from 10 h post-exposure to complete disappearance after 24 h. Seven polyphenols and a mixture thereof, chosen based on commercially recommended doses and adjusted to human realistic exposure, caused rat and human species-specific AhR responses. Two isoflavones (daidzein and genistein) induced rat AhR synergistic effects with FICZ and/or TCDD, while quercetin, chrysin, curcumin, resveratrol, and the mixture exerted a strong inhibitory effect on the human AhR. Strikingly, resveratrol and quercetin at their realistic nanomolar concentrations acted additively in the mixture to abolish human AhR activation induced by various TCDD concentrations. Taken together, these results illustrate the species-specific complexity of AhR transcriptional activities modulated by various ligands and highlight the need for studies of human-based approaches.
Show more [+] Less [-]Metallothioneins pattern during ontogeny of coastal dolphin, Pontoporia blainvillei, from Argentina Full text
2014
Polizzi, P.S. | Romero, M.B. | Chiodi Boudet, L.N. | Das, Krishna | Denuncio, P.E. | Rodriguez, D.H. | Gerpe, M.S.
peer reviewed | Metallothioneins are signals of metal exposure and widely used in biomonitoring. Franciscana dolphin is an endemic cetacean from the Southwestern Atlantic Ocean, classified as Vulnerable A3d by the IUCN. Metallothionein, copper and zinc in Franciscana were assessed in two geographic groups; one inhabits La Plata River estuary, anthropogenically impacted, and the other inhabits marine coastal ecosystems, with negligible pollution. Despite the environment, hepatic and renal MT concentrations were similar, but there was a declining trend from early to later developmental stages. Metallothionein K/L, Cu and Zn levels corresponded to normal reported ranges. MT was not related with Cd. Fetal concentrations were higher than its mother. These results and the health status of dolphins are suggesting that MT correspond to physiological ranges for the species, and they are closely to homeostasis of Zn and Cu, according to its ontogenetic changes. The information constitutes the first MT information on Franciscana dolphin and can be considered as baseline for the species conservation.
Show more [+] Less [-]Microsporidia parasites disrupt the responses to cadmium exposure in a gammarid Full text
2012
Gismondi, Eric | Rigaud, Thierry | Beisel, Jean-Nicolas | Cossu-Leguille, Carole
peer reviewed
Show more [+] Less [-]Inter-Island Variability in Trace Elements and Trophic Ecology of Brown Booby (Sula leucogaster) in the South Atlantic Full text
2025
Padilha, J A G | Almeida, A P | Souza-Kasprzyk, J | Silva, M | Cunha, L S T | Soares, T A | Paiva, T C | Bighetti, G P | Torres, J P M | Lepoint, Gilles | Michel, Loïc | Das, Krishna | Dorneles, Paulo Renato | FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | This study investigates essential (Mg, Ca, Fe, Mn, Cu, Zn, Se, Ni) and non-essential (Li, Be, Cr, Rb, Sr, Cs, Cd, Sn, Ba, and Pb) element concentrations and stable isotope (δ13C, δ15N, δ34S) compositions in feathers of Brown Boobies (Sula leucogaster) from three distinct Atlantic islands: the Archipelagos of Saint Peter and Saint Paul (SPSP), Abrolhos, and Cagarras. We aimed to investigate the ecological and environmental factors influencing these seabird populations and assess potential variations in contaminant exposure and dietary habits based on location, sex, and maturity stages. Our finding revealed significant geographical differences in trace element concentrations. The Brown Boobies from Cagarras had higher concentrations (mean ± SD, μg g-1) of Fe (29 ± 20) and Mn (0.82 ± 0.82) than those from Abrolhos (Fe: 21 ± 20; Mn: 0.24 ± 0.09) and SPSP (Fe: 15 ± 16; Mn: 0.21 ± 0.06). Tin concentrations were also higher in Cagarras (Sn: 0.02 ± 0.01) than in SPSP (Sn: 0.01 ± 0.01). Our analyses revealed significant differences in Li, Mg, Rb, and Zn concentrations between adults and juveniles. However, there were no sex-related differences in element concentrations within each locality. SIBER analyses revealed distinct dietary differences among the three Brown Boobies populations, with the Cagarras seabirds occupying a higher trophic position compared to the SPSP population. This study highlights the importance of considering different populations to understand contaminant exposure and ecological dynamics in Brown Boobies along the South Atlantic. The Cagarras population shows significantly higher contaminant levels, likely due to proximity to anthropogenic activities. These results highlight the necessity for ongoing monitoring to evaluate long-term effects on the more impacted population and to ensure seabird health and sustainability in the Atlantic Ocean.
Show more [+] Less [-]Dynamics of mercury stable isotope compounds in Arctic seals: new insights from a controlled feeding trial on hooded seals Cystophora cristata. Full text
2024
Pinzone, Marianna | Amouroux, David | Tessier, Emmanuel | Acquarone, Mario | Siebert, Ursula | Das, Krishna | FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
peer reviewed | Accurate interpretation of mercury (Hg) isotopic data requires the consideration of several biotic factors such as age, diet, geographical range, and tissue metabolic turnover. A priori knowledge of prey-predator isotopic incorporation rates and Hg biomagnification is essential. This study aims to assess Hg stable isotopes incorporation in an Arctic species of Phocidae, the hooded seal Cystophora cristata, kept in human care for 24 months (2012 - 2014) and fed on a constant diet of Norwegian Spring Spawning herring Clupea harengus. We measured THg, MMHg and iHg levels, as well as Hg stable isotope composition with both mass dependent (MDF) and mass independent (MIF) fractionation (e.g. δ202Hg and Δ199,200,201,204Hg) in hooded seal kidney, liver, hair and muscle, in addition to herring muscle. We then calculated Hg MDF and MIF isotopic fractionation between hooded seals and their prey. We found a significant shift in δ202Hg between hooded seal hair (+0.80‰) and kidney (-0.78‰), and herring muscle. In hooded seals tissues δ202Hg correlated positively with MMHg percentage. These findings suggest that tissue-specific Hg speciation is the major driver of changes in Hg isotopic fractionation rates in this Arctic predator. Δ199Hg, Δ200Hg, Δ201Hg and Δ204Hg values did not vary between herring and hooded seal tissues, confirming their utility as tracers of Hg marine and atmospheric sources in top predators. To our knowledge, this represents the first attempt to assess complex Hg isotope dynamics in the internal system of Arctic Phocidae, controlling the effects of age, diet, and distribution. Our results confirm the validity of Hg stable isotopes as tracers of environmental Hg sources even in top predators, but emphasize the importance of animal age and tissue selection for inter-study and inter-species comparisons. | 14. Life below water
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