LOEC
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OBJECTIVES: The aim of this study was to determine the effects of 96 hour exposure to selected solvents on the embryonic stages of zebrafish (Danio rerio). We investigated mortality and various types of changes which appeared (oedema, tail and eye defects, weak pigmentation, and deformation of the body). Based on the results, values of NOEC and LOEC for embryos of D. rerio were determined. METHODS: Embryonal toxicity tests were conducted according to OECD guideline 212. Ethanol and methanol were tested at concentrations of 0.1, 0.5, 1, 1.5, 2%; acetone at concentrations of 0.1, 0.5, 1, 1.25, 1.5%; and dimethylsulfoxide at concentrations of 1, 1.5, 2, 2.5, 3%. RESULTS: The LOEC values of ethanol and methanol were detected in the 1% concentration. Statistically significant changes (oedema) were reported in 1% ethanol, and oedema, weak pigmentation and deformation of the body were observed in 1% methanol. After exposure to acetone, the most common occurrence of oedema was in the 0.5% concentration (LOEC = 0.5%). The solvent dimethylsulfoxide caused oedema and body deformation at the 2% concentration (LOEC = 2%). CONCLUSIONS: The NOEC concentrations of the individual solvents were as follows: ethanol and methanol, 0.5%; acetone, 0.1%; and dimethylsulfoxide, 1.5%. These concentrations of individual solvents were higher than the maximum recommended concentration for toxicity tests on fish. For this reason, it can be assumed that the concentration of solvent allowed by the norm does not affect the procedure or results of such tests.
- MeSH
- abnormality očí chemicky indukované MeSH
- aceton toxicita MeSH
- dánio pruhované embryologie MeSH
- dimethylsulfoxid toxicita MeSH
- edém chemicky indukované MeSH
- embryo nesavčí účinky léků MeSH
- ethanol toxicita MeSH
- methanol toxicita MeSH
- mnohočetné abnormality chemicky indukované MeSH
- pigmentace kůže účinky léků MeSH
- rozpouštědla toxicita MeSH
- testy toxicity MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
OBJECTIVES: The aim of this study was to investigate effects of subchronic exposure to sublethal levels of terbutryn on growth and on histopathological changes in Danio rerio. DESIGN: The acute toxicity tests were performed on the juvenile stage of Danio rerio according to OECD No. 203 Fish, Acute Toxicity Test. The juvenile growth tests were performed on D. rerio according to the OECD method No. 215. Fish at the age of 20 days were exposed to the terbutryn environmental concentration commonly detected in the Czech rivers (0.02 microg L-1) and the range of sublethal concentrations of terbutryn (0.06, 0.2, 0.6 and 2 mg L-1) for 28 days. RESULTS: The 96hLC50 terbutryn mean value for the juvenile stage of D. rerio was 5.71 +/- 0.46 mg L-1. A significant decrease (p < 0.01) in the fish growth caused by terbutryn was observed in the concentration of 0.6 mg L-1. The value of NOEC was 0.2 mg L-1 and LOEC was 0.6 mg L-1 of terbutryn. We found the damage to tubular system of kidneys in the concentration of 0.6 mg L-1 of terbutryn. CONCLUSION: The environmental concentration of terbutryn in the Czech rivers did not have any effects on growth and on histopathological changes in D. rerio and this concentration is lower than determined LOEC and NOEC values of terbutryn.
- MeSH
- dánio pruhované růst a vývoj MeSH
- herbicidy aplikace a dávkování toxicita MeSH
- látky znečišťující vodu aplikace a dávkování toxicita MeSH
- ledviny účinky léků růst a vývoj patologie MeSH
- řeky MeSH
- tělesná hmotnost účinky léků MeSH
- testy toxicity MeSH
- triaziny aplikace a dávkování toxicita MeSH
- velikost těla účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
The goal of this study was to contribute to understanding of the mechanisms behind sensitivity differences between early and late instar larvae of Chironomus riparius and to address the influence of the differences in standard testing approaches on the toxicity evaluation. A 10-day contact sediment toxicity test was carried out to assess sensitivity to cadmium exposure in relation to different age and laboratory culture line origin of test organisms. Chironomid larvae of early (OECD 218 method) and late instar (US-EPA600/R-99/064 method) differed substantially in sensitivity of traditional endpoints (OECD: LOEC 50 and 10 μg Cd/g dry weight (dw); US-EPA: LOEC > 1000 and 100 μg Cd/g dw for survival and growth, respectively). Bioaccumulated cadmium and metallothioneins (MTs) concentrations were analyzed to investigate the role of MTs in reduced sensitivity to cadmium in late instar larvae. Metallothioneins were induced after treatment to greater Cd concentrations, but their levels in relation to cadmium body burdens did not fully explain low sensitivity of late instars to cadmium, which indicates some other effective way of detoxification in late instars. This study brings new information related to the role of MTs in age-dependent toxicant sensitivity and discusses the implications of divergence in data generated by chironomid sediment toxicity tests by standardized methods using different instars.
- MeSH
- Chironomidae účinky léků MeSH
- kadmium toxicita MeSH
- larva účinky léků MeSH
- metalothionein analýza metabolismus MeSH
- testy toxicity MeSH
- vystavení vlivu životního prostředí MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Teratogenic effects, which were remarkably similar to those induced by retinoic acids, have been seen in wild frogs indicating possible source of retinoids in the environment. Recent studies indicate that some cyanobacterial species can contain teratogenic retinoic acids (RAs) and their analogues. Retinoids are known to regulate important processes such as differentiation, development, and embryogenesis. The study investigated the effects of exudates (extracellular compounds) of two cyanobacteria species with retinoic-like activity and one algae species on embryonic development of amphibians. The retinoid-like activity determined by in vitro reporter gene assay reached 528ng retinoid equivalents (REQ)/L and 1000ng REQ/L in exudates of Cylindrospermopsis raciborskii and Microcystis aeruginosa, respectively, while algal exudates showed no detectable activity. Total mean of retinoid-like copounds into exudate was 35.6ng ATRA/mil.cells for M.aeruginosa and 6.71ng ATRA/mil.cells for C.raciborskii, respectively. Toxicity tests with amphibian embryos up to 96h of development were carried out according to the standard guide for the Frog Embryo Teratogenesis Assay Xenopus. Lowest observed effect concentrations (LOEC) of malformations (2.5-2.6µg/L REQ) were two times lower than LOEC for ATRA (5µg/L). The exudates of both cyanobacteria were indeed provoking diverse teratogenic effects (e.g. tail, gut and eyes deformation) and interference with growth in frogs embryos, while such effects were not observed for the algae. Xenopus embryos were also exposed to all-trans retinoic acid (ATRA) in concentration range (1-40µg/L) equivalent to the REQs detected in cyanobacterial exudates. ATRA (10µg/L) caused similar teratogenic phenotypes at corresponding REQs as cyanobacterial exudates. The study confirms the ability of some species of cyanobacteria to produce retinoids naturally and excrete them directly into the environment at concentrations which might have adverse influence on the development of amphibians.
- MeSH
- biotest MeSH
- chemické látky znečišťující vodu toxicita MeSH
- embryonální vývoj účinky léků MeSH
- fytoplankton metabolismus MeSH
- Microcystis účinky léků MeSH
- reportérové geny účinky léků MeSH
- sinice metabolismus MeSH
- teratogeny toxicita MeSH
- tretinoin metabolismus toxicita MeSH
- Xenopus laevis embryologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In this investigation thallium contents in soil and plants in the EuroRegion Neisse were analysed and the distribution determined. The median top-soil content is 0.5 mg/kg in the area investigated. In this low-contaminated area the moss Pleurozium schreberi contains 0.04-0.13 microg/g and the moss Polytrichumformosum between 0.01 and 0.05 microg/g Tl. The effects of thallium on man and the terrestrial environment were examined. In an epidemiological study a significant positive correlation was found between the thallium content of the two mosses and the incidence of diseases of the circulatory system. The LOEC for thallium in bioassays with terrestrial invertebrates and plants in artificial soil ranged from 1 to 500 mg/kg, which indicates an toxicity of thallium up to 100 times higher than that of Cadmium.
- MeSH
- epidemiologické monitorování MeSH
- hlemýždi účinky léků MeSH
- incidence MeSH
- kardiovaskulární nemoci epidemiologie etiologie MeSH
- látky znečišťující půdu analýza toxicita MeSH
- Lepidium účinky léků růst a vývoj MeSH
- lidé MeSH
- mechy chemie MeSH
- monitorování životního prostředí metody MeSH
- Oligochaeta účinky léků MeSH
- thallium analýza toxicita MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Německo MeSH
- Polsko MeSH
Toxicity of prometryne to early life stages of common carp was assessed. On the basis of accumulated mortality in the experimental groups lowest observed-effect concentration (LOEC) was estimated as 1100 µg/l; and no observed-effect concentration (NOEC) was 850 µg/l. Fulton's condition factor was significantly lower than in controls in fish exposed to 4000 µg/l after 7, 14, and 21 days. By day 14, fish exposed to 4000 µg/l prometryne showed significantly lower mass and total length compared to controls. Fish exposed the 1200 and 4000 µg/l showed delay in development, severe hyperaemia in gill, liver, and caudal and cranial kidney. Subchronic prometryne exposure of early-life stages of common carp at concentrations of 1200 and 4000 µg/l affected their survival, growth rate, early ontogeny, and histology.
- MeSH
- chemické látky znečišťující vodu toxicita MeSH
- játra účinky léků růst a vývoj MeSH
- kapři růst a vývoj MeSH
- ledviny účinky léků růst a vývoj MeSH
- pesticidy toxicita MeSH
- prometryn toxicita MeSH
- žábry účinky léků růst a vývoj MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The aim of this study was to perform the fish embryo acute toxicity test (FET) on zebrafish (Danio rerio) and the early-life stage toxicity test on common carp (Cyprinus carpio) with tramadol hydrochloride. The FET was performed using the method inspired by the OECD guideline 236. Newly fertilized zebrafish eggs were exposed to tramadol hydrochloride at concentrations of 10; 50; 100 and 200μg/l for a period of 144h. An embryo-larval toxicity test on C. carpio was performed according to OECD guideline 210 also with tramadol hydrochloride at concentrations 10; 50; 100 and 200μg/l for a period of 32 days. Hatching was significantly influenced in both acute and subchronic toxicity assays. Subchronic exposure also influenced early ontogeny, both morphometric and condition characteristics and caused changes in antioxidant enzyme activity. The LOEC value was found to be 10μg/l tramadol hydrochloride.
- MeSH
- chemické látky znečišťující vodu toxicita MeSH
- dánio pruhované embryologie růst a vývoj MeSH
- embryo nesavčí účinky léků MeSH
- embryonální vývoj účinky léků MeSH
- kapři růst a vývoj MeSH
- testy akutní toxicity MeSH
- tramadol toxicita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The aim of this study was to investigate the effects of subchronic exposure to atrazine on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver) in Danio rerio. Juvenile growth tests were performed on D. rerio according to OECD method No. 215. For 28 days, fish at an initial age of 30 days were exposed to the environmental atrazine concentration commonly detected in Czech rivers (0.3 microg/L) and a range of sublethal concentrations of atrazine (3.0, 30.0 and 90.0 microg/L). The results showed decreasing growth rates and morphological changes in the liver (dystrophic lesions of hepatocytes) at 90.0 microg/L of atrazine. The environmental concentration of atrazine in Czech rivers did not have any effect on fish growth and development of histopathological changes in D. rerio. The value of NOEC was 30.0 microg/L and the value of LOEC was 90.0 microg/L.
- MeSH
- atrazin toxicita MeSH
- chemické látky znečišťující vodu toxicita MeSH
- chování zvířat MeSH
- dánio pruhované růst a vývoj MeSH
- herbicidy toxicita MeSH
- játra účinky léků MeSH
- ledviny účinky léků MeSH
- řeky chemie MeSH
- rozvrh dávkování léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- žábry účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Impacts of neonicotinoids on non-target insects, including aquatic species, may significantly influence ecosystem structure and functioning. The present study investigated the sensitivity of Chironomus riparius to imidacloprid exposures during 24-h, 10- and 28-days by assessing larval survival, growth, emergence and oxidative stress-related parameters. C. riparius exhibited high sensitivity compared to other model aquatic species with acute 24-h LC50 being 31.5 μg/L and 10-days LOEC (growth) 0.625 μg/L. A 28-days partial life cycle test demonstrated imidacloprid effects on the emergence of C. riparius. Exposure to sublethal concentrations during 10-days caused an imbalance in the reduced and oxidized glutathione (GSH and GSSG), and slightly induced lipid peroxidation (increased malondialdehyde, MDA). Our results indicate that oxidative stress may be a relevant mechanism in the neonicotinoid toxicity, reflected in the insect development and life cycle parameters.
- MeSH
- Chironomidae účinky léků MeSH
- dusíkaté sloučeniny toxicita MeSH
- hmyz MeSH
- neonikotinoidy toxicita MeSH
- oxidační stres MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Environmental concentrations of pharmaceutical residues are often low; nevertheless, they are designed to have biological effects at low doses. The aim of this study was to assess the effects of salicylic acid on the growth and development of common carp (Cyprinus carpio) early life stages with respect to antioxidant defence enzymes. An embryo-larval toxicity test lasting 34 days was performed according to OECD guidelines 210 (Fish, Early-life Stage Toxicity Test). The tested concentrations were 0.004, 0.04, 0.4, 4 and 20mg/l of salicylic acid. Hatching, early ontogeny, and both morphometric and condition characteristics were significantly influenced by subchronic exposure to salicylic acid. Also, changes in antioxidant enzyme activity and an increase in lipid peroxidation were observed. The LOEC value was found to be 0.004 mg/l salicylic acid. The results of our study confirm the suggestion that subchronic exposure to salicylic acid at environmental concentrations can have significant effects on aquatic vertebrates.
