Search results for "Ecotoxicology"

Carbamazepine exposure in the sea anemones Anemonia sulcata and Actinia equina: Metabolite identification and physiological responses

2020

Trabajo presentado en el 11º Congreso Ibérico, 8º Iberoamericano de Contaminación y Toxicología (CICTA 2018) celebrado en la Escuela Técnica Superior de Ingeniería de Montes, Forestal y del Medio Natural, Madrid del 11 al 13 de julio de 2018

Recommendations for ecotoxicity testing with stygobiotic species in the framework of groundwater environmental risk assessment.

2019

As a consequence of the growing global dependence on groundwater resources, environmental risk assessments (ERA) for groundwater are increasingly required and, with that, ecotoxicological studies with groundwater fauna (stygofauna). However, the literature on the ecotoxicological studies with stygobiotic species (i.e. species that complete their life cycle exclusively in groundwater) has not expanded significantly since the first paper published in this field. The limitations regarding the use of stygobiotic species for ecotoxicological testing are clear and consistent across the globe; stygobiotic species are often 1) naturally present in low numbers, 2) difficult to collect, and 3) diffic…

The toxicity and concentrations of PAHs in creosote-contaminated lake sediment

1999

Sediment samplers, divided into three layers (0 – 10, 10 – 20 and 20 – 30 cm), were collected from 16 sites in Lake Jamsanvesi, Central Finland. The acute toxicity of pore waters and elutriates (sediment + water 1:4 v/v) were studied by bioluminescence inhibition test and by immobilisation of water fleas (Daphnia magna Straus). Concentrations of polycyclic aromatic hydrocarbons (PAHs) in sediments and elutriates were measured by gas chromatography using flame ionization detection (GC/FID). The highest total PAH concentration was 3.3 mg/g dry weight in the sediment and up to 1.7 mg/l in the elutriate of the uppermost (0 – 10 cm) layer, also being the most toxic to photoluminencent bacteria, …

Evaluation of biodegradation of nonylphenol ethoxylate and lignin by combining toxicity assessment and chemical characterization.

2009

Abstract The aerobic biodegradation of commercial nonylphenol ethoxylate (NPE) mixture and alkali lignin was studied using the OECD headspace test accompanied by the simultaneous measurement of ecotoxicity directly from the biodegradation liquors and by the follow-up of the chemical composition of the studied chemicals. NPE degradation was dependent on the inoculum source: approximately 40% of NPE was mineralized into CO2 during the 4-week experiment when inoculum from Helsinki City wastewater treatment plant (WWTP) was used, and only 12% was mineralized when inoculum from Jyvaskyla City WWTP was used. Chemical analyses revealed a shift in the ethoxylate chain length from longer to shorter …

Chromatographic retention–activity relationships for prediction of the toxicity pH-dependence of phenols

2007

Abstract An investigation of the use of the chromatographic retention (log  k ) as an in vitro approach for modeling the pH-dependence of the toxicity to Guppy of phenols is developed. A data set of 19 phenols with available experimental toxicity–pH data was used. The importance of the mechanism of toxic action (MOA) of phenols was studied. log  k data at three pH values were used for the phenols classification and two groups or ‘MODEs’ were identified. For one ‘MODE’ a quantitative retention–activity relationship (QRAR) model was calculated. Finally, the model was used to assess the toxicity to Guppy of phenols at different pH values. The results of this investigation suggest that chromato…

Long-term effect of temperature on bioaccumulation of dietary metals and metallothionein induction in Sparus aurata

2012

Previous studies have demonstrated that the commercial feed of aquacultured fish contains trace amounts of toxic and essential metals which can accumulate in tissues and finally be ingested by consumers. Recently rising temperatures, associated to the global warming phenomenon, have been reported as a factor to be taken into consideration in ecotoxicology, since temperature-dependent alterations in bioavailability, toxicokinetics and biotransformation rates can be expected. Sparus aurata were kept at 22. °C, 27. °C and 30. °C for 3. months in order to determine the temperature effect on metallothionein induction and metal bioaccumulation from a non-experimentally contaminated commercial fee…

Effect of the insecticide methylparathion on filtration and ingestion rates of Brachionus calyciflorus and Daphnia magna

1993

The freshwater rotifer Brachionus calyciflorus and the cladocera Daphnia magna were exposed to sublethal levels of methylparathion to determine the effect on filtration and ingestion rates. The experiments were performed using the unicellular algae, Nannochloris oculata in a density of 5 × 105 cell/ml. Prior to feeding experiments, preliminary acute toxicity tests were carried out to determine 24-h LC50 values for both species, these values indicated that Daphnia magna was more sensitive to methylparathion acute exposure than Brachionus calyciflorus was. Rates of filtration and ingestion declined with increasing methylparathion concentrations after an exposure of 5 h to this toxicant. The e…

Humusvielas, to mijiedarbība ar augsni veidojošiem komponentiem un humusvielu imobilizācija

2007

Linda Eglīte Humusvielas, to mijiedarbība ar augsni veidojošiem komponentiem un humusvielu imobilizācija Viens no ap mums esošās dabas vides izpētes uzdevumiem ir izprast, kas vidē notiek ar dzīvos organismus veidojošajām vielām. Dabiskas izcelsmes organiskās vielas ir ne tikai dzīvos organismus veidojošās vielas, to metabolīti, bet arī dzīvo organismu sadalīšanās procesu noturīgie produkti. Tie līdz ar to uzskatāmi par nozīmīgu dabas vides sastāvdaļu, kas ietekmē dabā noritošos procesus, kā arī piesārņojošo vielu pārvērtības, tām nonākot apkārtējā vidē. Pēc masas nozīmīgāko daļu no dabiskas izcelsmes organiskajām vielām veido humusvielas. Tās var uzskatīt par visvairāk izplatīto organisko …

Vides apstākļu ietekme uz mikro- un makroelementu saturu pārtikas produktos Latvijā

2014

Bez vitāli svarīgo mikro- un makroelementu ieneses pārtikā no vides (augsnes, ūdens un gaisa) ir iespējams arī barības ķēdes, t. sk., pārtikas piesārņojums ar toksiskiem vai potenciāli toksiskiem elementiem, piemēram, As, Cd, Hg, Pb. Promocijas darba mērķa ietvaros tika veikta Latvijā iegūtu pārtikas produktu paraugu mikro- un makroelementu sastāva kvantitatīvā analīze, lai noskaidrotu vides apstākļu ietekmi uz elementu koncentrāciju un ieneses ceļiem pārtikā. Papildus, lai vērtētu elementu biopieejamību barības ķēdē, tika veikta eksperimentāla pārtikas kultūraugu audzēšana mākslīgi piesārņotā augsnē. Iegūtie dati liecina par vairāku dabiskas un antropogēnas izcelsmes vides apstākļu, piemēr…

Chemistry and environment (CE) in Spain.

2008