Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 4

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  ecotoxicological test
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
As part of eco-toxicological tests on Artemia salina, the impact of the most commonly used fertilizers in Morocco was assessed (Ammonium Sulfate, Ammonium Nitrate, and a mixture of Nitrogen 10%, Phosphorus 30% and Potassium 10%), with Potassium Bichromate (K2Cr2O7) as reference substance at different concentrations (10, 20, 40, 80, 160, 320 mg/l), for 24 hours. The results of the statistical study revealed that the lethal effects caused by the three agrochemicals increase with the concentration and vary from one substance to another in a significant way. There is a higher sensitivity to ammonium sulphate (the concentration that kills 50% of the animals: 37.32 mg/l ± 6.09) followed by ammonium nitrate the concentration that kills 50% of the animals: 110.7 mg/l ± 7.11), and a mixture of Nitrogen 10%, Phosphorus 30% and Potassium 10% (the concentration that kills 50% of the animals: 143.13 mg/l ± 23.12). Therefore, Artemia salina exhibits sensitivity to agrochemicals and can be considered as a good biomonitoring tool for future toxicological analysis of agrochemicals.
EN
Cigarette butts (CBs) have only recently begun to be considered environmentally harmful waste. CBs are common waste in the environment, that can cause air, soil, and water pollution and pose a threat to the living. CBs should be treated as toxic and hazardous waste due to its slow decomposition and accumulation of many toxic substances. There is a lack of research on the adaptation of CBs to the environment and what impact they have on vegetation. Therefore, the present work aimed to understand the toxicity of smoked CBs. Leachates of various concentrations were assessed with ecotoxicological tests. The effect of CBs on germination and development of plants at their early stage of growth was determined. Seeds of Sinapis alba L. and Hordeum vulgare L. were used in the CBs toxicity test. Two-way ANOVA was conducted to compare the main effects on plants. From the results, it is evident that low concentrations of toxic substances contained in CBs have a positive effect on plants; however, Hordeum vulgare L. expresses higher toxic resistance than Sinapis alba L. It has been proven that high concentrations of CBs in a water solution have negative effects on seed germination and radical growth. This research shows that varied plant species can cope with different levels of contamination by hazardous elements. CBs are an important source of contamination for the environment and the hazardous elements that are released from them when inappropriately disposed of can impair the development of plants and accumulate in them.
EN
As part of the ecotoxicological tests on anuran tadpoles, the authors propose to study the sensitivity of different stages towards a nitrogenous compound frequently used in Morocco (Ammonium sulphate). For this purpose, the acute toxicity tests on tadpoles of two species (Bufo mauritanicus and Rana ridibunda) belonging to different stages of development were carried out. The lethal effects after 96 hours caused by the pollutant used as a reference (potassium dichromate) as well as ammonium sulfate increase with concentration and vary according to the stage of development. Significant differences were observed in the sensitivity of the tadpoles to pollutants according to the stage of development. The tadpoles belonging to the early stages of development (stage 24 according to Gosner, 1960) show greater acute effects on pollutants than the tadpoles belonging to the advanced stages of development (Stage 36 according to Gosner, 1960). After 96 hours, the lowest effective concentration (LOEC) is observed in the tadpoles belonging to the early stages of development (Stage 24 according to Gosner, 1960) in Rana ridibunda exposed just to the lowest concentration used (20 mg/l of ammonium sulphate). Therefore, ammonium sulfate may play a role in the local decline of amphibians.
EN
The aim of study was to optimize alternative acute toxicity tests involving toxic compounds of Cr(VI) and Zn(II) and two representatives of the Lemnaceae species (Lemna gibba and Spirodela polyrhiza) as testing organisms and to compare their relative sensitivity with Lemna minor and Daphnia magna. The most sensitive organism to both metals was D. magna. The highest duckweed sensitivity to Cr(VI) and Zn(II) was determined for S. polyrhiza and L. gibba, respectively. The compound of Cr(VI) provided significantly higher toxicity effect towards the testing organisms than Zn(II). L. gibba proved the most suitability for assessment of environmental quality due to the highest duckweed sensitivity. In contrast, L. minor and S. polyrhiza showed the lowest sensitivity to Cr(VI) and Zn(II), respectively. It was probably caused by their antioxidant ability, and thus they may be the most effective for removal of metals from water environment.
PL
Celem pracy była optymalizacja alternatywnych testów ostrej toksyczności z udziałem toksycznych związków Cr(VI) i Zn(II) i dwóch przedstawicieli gatunku Lemnaceae (Lemna gibba i Spirodela polyrhiza) jako organizmów testowych i porównanie ich względnej czułości w stosunku do Lemna minor i Daphnia magna. Organizmem najbardziej wrażliwym na oba metale była D. magna. Największą wrażliwość na Cr(VI) i Zn(II) stwierdzono odpowiednio dla L. gibba i S. polyrhiza. Związek chromu(VI) powodował silniejszy efekt toksyczny w organizmach testowych niż Zn(II). Ze względu na najwyższą czułość L. gibba jest najlepszym biomonitorem do oceny jakości środowiska naturalnego. Najmniejszą wrażliwość na Cr(VI) i Zn(II) wykazały odpowiednio L. minor i S. polyrhiza. Jest to prawdopodobnie spowodowane ich zdolnościami antyoksydacyjnymi i dlatego mogą być one najbardziej skuteczne w usuwaniu metali ze środowiska wodnego.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.