The Effect of TiO2 Nanoparticles on the Aquatic Ecosystem: A Comparative Ecotoxicity Study with Test Organisms of Different Trophic Levels

A comprehensive ecotoxicological assessment was carried out with Degussa VP nano TiO2 suspension applying a bioluminescent bacterium (Aliivibrio fischeri), algae (Pseudokirchneriella subcapitata, Scenedesmus subspicatus and Chlorella vulgaris), a protozoon (Tetrahymena pyriformis), the water flea (Daphnia magna) and an aquatic macrophyte, Lemna minor. TiO2 nanoparticles were toxic in the set of the conducted tests, but the toxicity level varied with the organisms and endpoints. According to our results the concentrations, the duration and the mechanisms of exposure are contributing factors to the toxicity of nanoparticles. The Tetrahymena phagocytic activity, the Daphnia heartbeat rate and the Lemna total chlorophyll content as ecotoxicity endpoints showed outstanding sensitivity. These organisms showed significant behavioural and physiological changes when exposed to low TiO2 nanoparticle concentrations (0.1 and 0.05 µg/L) considered to be lower than the predicted environmental concentration in surface waters. These results reveal the importance of behavioural and physiological assays in assessing the impact of nanoparticles and indicate that nanosized TiO2 may pose risks to the aquatic ecosystem

Tetrahymena pyriformis Phagocytic Activity Test for Rapid Toxicity Assessment of Aquatic Micropollutants

The increasing worldwide contamination of freshwater ecosystems with micropollutants such as pharmaceuticals, personal care products, hormones, industrial chemicals and pesticides is a key environmental problem facing humanity nowadays. In order to assess the adverse effect of six organic micropollutants (atrazine, bisphenol A, dibutyl phthalate, 17β-estradiol, 3,4-dichlorophenol and Na-diclofenac) a short term phagocytic activity test was applied with Tetrahymena pyriformis representing an important trophic level of aquatic ecosystems.Significant concentration-dependent response in phagocytic activity was experienced to 17β-estradiol and other endocrine disrupting compounds such as 3,4-dichlorophenol, atrazine and dibutyl phthalate with lowest observed effect concentration of 0.01; 0.005; 0.05; 0.05 µg/L, respectively. Although bisphenol A and Na-diclofenac did not result in a concentration-dependent response, significant changes in phagocytic activity were observed.Our results suggest that the phagocytic activity assay relying on a basic cell response can be a valuable method for the early and sensitive indication of adverse effects of micropollutants

Tiered Approach for the Evaluation of Environmental Impacts of Triclosan on Aquatic Ecosystems

The synthetic broad-spectrum antibacterial agent triclosan is one of the most commonly encountered emerging micro-pollutant in the aquatic environment due to the extensive use since 1968 mainly in cosmetics and household cleaning products and the partial elimination from wastewater. Its low water solubility, high sorption coefficient to organic matter, accumulation potential in fatty tissues and its low acute toxicity determined by conventional ecotoxicological tests suggest that its risk is more related to chronic effects requiring risk assessment based on more sensitive ecotoxicological methods. In this paper the short- and midterm ecotoxicological effects of triclosan were investigated using various test systems taking into account ecological complexity and environmental relevance. Acute single-species, simplified microcosm experiments and complex multi-species microcosm experiments were conducted with the determination of sublethal physiological and behavioral endpoints including the Daphnia magna heartbeat rate and feeding activity, the Heterocypris incongruens movement parameters and the Lemna minor chlorophyll content and root length. All physiological and behavioral endpoints indicated sensitively the adverse effect of triclosan in the concentration range of 4–25.6 µg/L. In some cases, responses of selected organisms in single-species laboratory tests did not correspond to those of the higher levels of test systems. Daphnia sensitivity increased with the level of the test system for all chosen endpoints except the heartbeat rate. Considering the varying ecological complexity of the assembled test systems, according to our results the exposure time and the different combinations of exposure routes were the most decisive parameters in terms of triclosan ecotoxicity and endpoint sensitivity

Hydrogen peroxide oxidation for in situ remediation of trichloroethylene – from the laboratory to the field

In this paper we present the remediation possibilities of a trichloroethylene contaminated site of a former metalworking plant in Hungary, where high TCE concentration (150 μg/L to 35.000 μg/L) was detected in the groundwater. Lab-scale experiments were performed to compare the potential bioremediation technology-alternatives eg.: enhanced biodegradation; pump & treat by UV irradiation (photodegradation); in situ chemical oxidation (ISCO) applying different oxidants (KMnO4, Na2S2O8 and H2O2). The lab-scale experiments showed in all cases reduction of the TCE-concentration of the water. Comparing the removal efficacy and concerning the time requirement ISCO was the most effective in laboratory studies

Assessing Toxicity of Organic Aquatic Micropollutants Based on the Total Chlorophyll Content of Lemna minor as a Sensitive Endpoint

The present study examined the chlorophyll content in a 7-day contact time experiment series. Lemna minor was exposed to caffeine, benzophenone, bisphenol A, 3,4-dichlorophenol, metamizole-Na, Na-diclofenac, acetochlor, atrazine, diuron, metazachlor and metolachlor to find a convenient sensitive response to the tested chemicals including some emerging micropollutants. The results demonstrated the differences in sensitivity to the tested micropollutants. As anticipated the industrial chemicals and the pesticides were the most toxic. The lowest observed effect concentration (LOEC) values determined for 3,4-dichlorophenol, acetochlor, diuron, metazachlor and metolachlor were 2.5 µg/L, 0.05 µg/L, 0.5 µg/L, 5 µg/L and 0.5 µg/L, respectively. These values were comparable with the environmental concentrations reported in literature. Our study provides valuable information on the feasibility of Lemna minor total chlorophyll method as a sensitive and reliable bioassay for testing toxicity at µg/L range and it may support risk assessment of organic micropollutants in freshwater ecosystems

How Does Experimental Design Modify the Result of Daphnia magna Heartbeat Rate Test? ─ Analyses of Factors Affecting the Sensitivity of the Test System

Development of an unconventional test method involves usually the comparison of biological responses under a variety of test conditions. The quality of these biological methods relies on an appropriate experimental design. The Daphnia magna heartbeat rate as a physiological endpoint for assessing aquatic pollution has been of minor interest so far; nonetheless, this could be an early and sensitive indicator of the harmful effect of micropollutants. Our aim was to set up the optimal experimental design of the heartbeat rate test. The studied factors were the composition of the test medium, the age of the test organism, and the exposure time, at triclosan concentrations between 0.2–2000 μg/L. According to the evaluation of test results the optimal test condition for the heartbeat rate test assumes tap water as test medium, 10-day-old test organisms and 48 h exposure time

Fabry-betegség - Diagnosztikai útmutató

A Fabry-kór a lizoszomális tárolási betegségek csoportjába tartozó, X-kromoszómához kötötten, recesszív módon öröklődő betegség, amely a globotriaosylceramid felhalmozódásához vezet a szervezet legkülönbözőbb szöveteiben. A betegség első tünetei többnyire gyermekkorban jelentkeznek, a progresszió során a betegek súlyos szervi károsodásokkal és korai halálozással számolhatnak. Elsősorban fiúk és férfiak érintettek, azonban a betegség tüneteit heterozigóta nők esetében is megfigyelhetjük, de náluk a kórkép súlyossága változó, általában enyhébb lefolyású. Az enzimpótló kezelések megjelenése szükségessé tette, hogy részletes diagnosztikus és terápiás protokollt dolgozzunk ki. A jelen dolgozatban megjelenő ajánlásokat egy, a magyarországi Fabry-betegek kezelésében aktívan részt vevő orvosokból, a diagnosztika területén dolgozó biológosukból és egyéb szakemberekből álló multidiszciplináris munkacsoport foglalta össze. A munkacsoport áttekintette a korábbi klinikai tanulmányokat, a publikált vizsgálatokat és a közelmúltban megjelent nemzetközi és nemzeti útmutatókat. | Fabry disease is a rare, X-linked lysosomal storage disorder that leads to accumulation of globotriaosylceramide in different tissues of the body. The disease is progressive, first symptoms usually present in childhood. Consequencies of the diseases are disability and premature death. The disease in females could be as severe as in males although women may also be asymptomatic. The possibility of enzyme replacement therapy has made it necessary to elaborate a comprehensive guideline for the diagnosis and treatment follow-up. The guideline was established by a Hungarian multi-disciplinary working group, consisting of physicians who are involved in health care of Fabry patients. Previous clinical studies, published materials, and recently established international treatment guidelines were reviewed by the group

Fabry-betegség – terápiás útmutató

A Fabry-kór a lizoszomális tárolási betegségek csoportjába tartozó, X-kromoszómához kötötten, recesszív módon öröklődő betegség, amely a globotriaozilceramid felhalmozódásához vezet a szervezet legkülönbözőbb szöveteiben. A betegség első tünetei többnyire gyermekkorban jelentkeznek, a progresszió során a betegek súlyos szervi károsodásokkal és korai halálozással számolhatnak. Elsősorban férfiak érintettek, azonban a betegség tüneteit heterozigóta nők esetében is megfigyelhetjük, de náluk a kórkép súlyossága változó, általában enyhébb lefolyású. Az enzimpótló kezelések megjelenése szükségessé tette, hogy részletes diagnosztikus és terápiás protokollt dolgozzunk ki. A jelen dolgozatban megjelenő ajánlásokat egy, a magyarországi Fabry-kóros betegek kezelésében részt vevő orvosokból, a diagnosztika területén dolgozó biológosukból és egyéb szakemberekből álló multidiszciplináris munkacsoport foglalta össze. A munkacsoport áttekintette a korábbi klinikai tanulmányokat, a publikált vizsgálatokat és a közelmúltban megjelent nemzetközi és nemzeti útmutatókat. | Fabry disease is a rare, X-linked lysosomal storage disorder that leads to accumulation of globotriaosylceramide in different tissues of the body. The disease is progressive and the first symptoms usually present in childhood. Consequences of the disease are disability and premature death. The disease in females could be as severe as in males although women may be asymptomatic. The possibility of enzyme replacement therapy has made it necessary to elaborate a comprehensive guideline for the diagnosis and treatment follow-up. The guideline has been summarized by a Hungarian multi-disciplinary working group consisting of physicians who are involved in diagnosis and care of Fabry patients. Previous clinical studies, published articles, and recently established international treatment guidelines were reviewed by the group