Effects of Silver Nanoparticles and Ions Exposure on the Soil Invertebrates Folsomia candida and Enchytraeus crypticus.

The aim of the study was to assess the effects of silver nanoparticles (AgNPs1 = 2.7 d·nm, AgNPs2 = 6.5 d·nm) and silver nitrate (AgNO3) on Enchytraeus crypticus and Folsomia candida using toxicity tests (OECD Guideline 220, 232). A 28-day chronic toxicity study was performed to evaluate the reproduction and mortality rate. E. crypticus reproduction was more sensitive to AgNO3 with a 28dEC50 of 86.40 (62.52-119.4) mg·kg-1 dry weight (d.w.) compared to AgNPs1 (28dEC50 = 119.3 (60.4-235.6) mg·kg-1 d.w). Similarly, the reproduction of F. candida was inhibited the most by AgNO3 with a 28dEC50 of 126.2 (104.2-152.9) mg·kg-1 d.w. followed by AgNPs1 (28dEC50 = 158.7 (64.05-393.2) mg·kg-1 d.w.) and AgNPs2 (28dEC50 = 206.4 (181.9-234.1) mg·kg-1 d.w.). No mortalities were observed for tested soil invertebrates exposed to AgNPs at concentrations up to 166 mg·kg-1 d.w. of AgNPs1 and 300 mg·kg-1 d.w. of AgNPs2, respectively. It was found that silver ions are more toxic in comparison with AgNPs.

Effect of Gold Nanoparticles and Ions Exposure on the Aquatic Organisms.

An increase in the production and usage of gold nanoparticles (AuNPs) triggers the necessity to focus on their impact on ecosystems. Therefore, the purpose of this study was to investigate the acute toxicity of AuNPs and ionic gold (Au (III)) to organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (crustacean Daphnia magna, embryos of Danio rerio) and decomposers (bacteria Vibrio fischeri). The organisms were exposed according to a standardized protocol for each species and endpoints. The AuNPs (1.16 and 11.6 d.nm) were synthesized using citrate (CIT) and polyvinylpyrrolidone (PVP) as capping agents, respectively. It was found, that Au (III) was significantly more toxic than AuNPs PVP and AuNPs CIT. AuNPs showed significant toxicity only at high concentrations (mg/L), which are not environmentally relevant in the present time, but a cautious approach is advised, due to the possibility of interactions with other contaminants.

Reproductive toxicity of fluoroquinolones in birds.

BACKGROUND: While commercial poultry and captive birds are exposed to antimicrobials through direct medication, environmental pollution may result in contamination of wild birds. Fluoroquinolones are commonly used medications to treat severe avian bacterial infections; however, their adverse effects on birds remain understudied. Here, we examine toxicity of enrofloxacin and marbofloxacin during the egg incubation period using the chicken (Gallus Gallus domesticus) as a model avian species. Laboratory tests were based on eggs injected with 1, 10 and 100 µg of fluoroquinolones per 1 g of egg weight prior to the start of incubation and monitoring of chick blood biochemistry, reproductive parameters and heart rate during incubation. RESULTS: Eggs treated with fluoroquinolones displayed reduced hatchability due to embryonic mortality, particularly on day 13 of incubation. Total hatching success showed a similar pattern, with a significantly reduced hatchability in low and high exposure groups treated with both enrofloxacin and marbofloxacin. From 15 to 67% of chicks hatching in these groups exhibited joint deformities. Hatching one-day pre-term occurred with a prevalence of 31 to 70% in all groups treated with fluoroquinolones. Embryonic heart rate, measured on days 13 and 19 of incubation, increased in all enrofloxacin-treated groups and medium and high dose groups of marbofloxacin-treated eggs. Blood biochemistry of chicks sampled at hatch from medium dose groups showed hypoproteinaemia, decreased uric acid and increased triglycerides. Chicks from the enrofloxacin-treated group displayed mild hyperglycaemia and a two-fold rise in the blood urea nitrogen to uric acid ratio. Principal components analysis based on blood biochemistry clearly separated the control bird cluster from both enrofloxacin- and marbofloxacin-treated birds. CONCLUSIONS: Fluoroquinolones induce complex adverse effects on avian embryonic development, considerably reducing the performance of incubated eggs and hatching chicks. Cardiotoxicity, which quickens embryonic heart rate, meant that the total number of heart beats required for embryogenesis was achieved earlier than in the standard incubation period, resulting in pre-term hatching. Our data suggest that enrofloxacin has a higher potential for adverse effects than marbofloxacin. To conclude, care should be taken to prevent exposure of reproducing birds and their eggs to fluoroquinolones.

Evaluation of platinum nanoparticles ecotoxicity using representatives of distinct trophic levels of aquatic biocenosis.

OBJECTIVES: The aim of this study was to clarify the influence of three different sizes of platinum nanoparticles on aquatic ecosystem and assess the toxic effect in term of particle size. Tests were conducted on organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (water fleas Daphnia magna) and decomposers (bacteria Vibrio fischeri). DESIGN: Experiments were carried out methodologically in accordance with the following standards: OECD 221 guideline (Lemna sp. Growth Inhibition test), OECD 202 guideline (Inhibition of the mobility of Daphnia magna) and ISO 11348-2 (Inhibitory effect of platinum nanoparticles on the light emission of Vibrio fischeri). RESULTS: The most toxic have been the smallest sized platinum nanoparticles for all tested organisms. The highest toxicity of all tested samples (Pt1, Pt2, Pt3) was observed in bacteria (30´EC50 = 135.47; 167.94; 254.64 µg.L-1), respectively. The lowest toxicity was recorded for Daphnia (48hEC50 = 405.74; 413.24; 514.07 µg.L-1), respectively. CONCLUSION: The ecotoxicity of platinum nanoparticles varies considerably according to the test organisms and particle size.

Ecotoxicity of selected antibiotics for organisms of aquatic and terrestrial ecosystems.

OBJECTIVES: The aim of this study was to assess the ecotoxicity of selected antibiotics (i.e. penicillin G, vancomycin and tetracycline) using ecotoxicological tests. Tests were conducted on organisms representing all trophic levels of the aquatic ecosystem, namely producers (green freshwater algae Pseudokirchneriella subcapitata), consumers (water fleas Daphnia magna) and decomposers (bacteria Vibrio fischeri). The effect of antibiotics on the representative of edaphon was measured by testing the inhibition of the reproduction of springtails Folsomia candida and earthworms Eisenia fetida. DESIGN: Methodologically, the procedure was carried out in accordance with the following standards: OECD 201 (Fresh water algal growth inhibition test), OECD 202 (Inhibition of the mobility of Daphnia magna), ISO 11348-2 (Inhibitory effect of antibiotics on the light emission of Vibrio fischeri), OECD 232 (Inhibition of reproduction of Collembola Folsomia candida) and OECD 222 (Inhibition of reproduction of Eisenia fetida). RESULTS: In aquatic organisms the highest level of toxicity was shown by tetracycline to algae (72hEC50 = 1.82 mg.l-1) and daphnia (48hEC50 = 8.16 mg.l-1). The least toxic for all test organisms was penicillin G. The results of the tests performed on the representative of edaphon, Folsomia candida, showed that its reproduction was most inhibited by penicillin G (28dEC50 = 328 mg.kg-1) and least by tetracycline (28dEC50 = 2560 mg.kg-1). Similar results were observed in Eisenia fetida (56dEC50 = 348 mg.kg-1 for penicillin G and 56dEC50 = 2735 mg.kg-1 for tetracycline. CONCLUSION: The ecotoxicity of antibiotics differed significantly depending on the test organism and testing conditions.

Cytotoxicity of ketamine, xylazine and Hellabrunn mixture in liver-, heart- and kidney-derived cells from fallow deer.

OBJECTIVES: Chemical restraint of wild animals is practiced to accomplish intended procedures such as capture, clinical examination, collection of diagnostic samples, treatment and/or transport. Extra-label use of animal medicinal drugs is often necessary in wildlife because most approved therapeutics do not list wild species on the labelling. Here, we used cellular in vitro models, a cutting-edge tool of biomedical research, to examine cytotoxicity of anaesthetic agents in fallow deer and extrapolate these data for anaesthetic risks in wildlife. METHODS: We examined the cytotoxic effects of ketamine, xylazine, and ketamine-xylazine, i.e. the Hellabrunn mixture, on liver-, heart- and kidney-derived cell cultures prepared from a fallow deer (Dama dama) specimen. In line with preliminary studies we exposed cells to 10 µM, 50 µM, 100 µM, 1 mM, and 10 mM ketamine or xylazine. The combination of ketamine-xylazine was dosed at 0.025+0.02 mg/ml, 0.05+0.04 mg/ml, 0.75+0.06 mg/ml, 0.1+0.08 mg/ml, and 0.125+0.1 mg/ml per one well containing 10 000 cells. The quantification of cytotoxicity was based on lactate dehydrogenase activity released from damaged cells. RESULTS: Liver-derived cells show higher sensitivity to the cytotoxic effects of both ketamine and xylazine administered as single drugs when compared with cells cultured from the heart and kidney. The Hellabrunn mixture induced significantly higher cytotoxicity for kidney-derived cells ranging from 16.78% to 35.6%. Single and combined exposures to ketamine and xylazine resulted only in high-dose cytotoxicity in the heart-derived cells. CONCLUSIONS: Our results indicate that immobilization drugs significantly differ in their cytotoxic effects on cells derived from various organs of the fallow deer.

Impact of platinum group elements on the soil invertebrate Enchytraeus crypticus.

OBJECTIVES: The platinum group elements (PGE) platinum (Pt), palladium (Pd), and rhodium (Rh) are used in automobile catalytic converters, from which they have been emitted into the environment to an increasing degree over the last 20 years. Despite the bioavailability of these metals to plants and animals, studies determining the effects of PGE on organisms are extremely rare. Enchytraeids are ecologically relevant soil organisms, due to their activity in decomposition and bioturbation in many soil types worldwide. DESIGN: The experiments were carried out as described in the OECD Guideline 220 [CSN EN ISO 16387--Soil quality--Effects of pollutants on Enchytraeidae (Enchytraeus sp.)--Determination of effects on reproduction]. The reproductive effects of platinum (PtCl4), palladium (PdCl2) and rhodium (RhCl3) were examined. The concentrations of PGE tested were as follows: 5, 10, 25, 50 and 100 µmol x L(-1) PdCl2; 50, 100, 150, 200 and 250 µmol x L-1 PtCl4/RhCl3. The EC50 (medium effective concentration) was determined after 28 days of exposure. The inhibition of the reproduction of PGE-exposed enchytraeids was compared against controls. RESULTS: Values of 28dEC50 of PtCl4, PdCl2 and RhCl3 amounted to 161.9 µmol x L(-1), 70.0 µmol x L(-1) and 246.6 µmol x L(-1), respectively. We can confirm that the relative order of toxicities is Pd (II) >Pt(IV) >>Rh(III). CONCLUSION: To the best of our knowledge, this is the first study to use Enchytraeus crypticus as an indicator species to assess the risk of soil contamination by platinum, palladium and rhodium. Results of this study contribute important data on the ecotoxicity of a rarely studied elements.

Study of the influence of platinum, palladium and rhodium on duckweed (Lemna minor).

OBJECTIVES: Road traffic pollutants and the residues of cytostatics that are widely used in anti-cancer therapy are a significant sources of platinum group elements (PGE; Pt, Pd and Rh) in environment. These metals can migrate into sewage and thus pollute surface waters. The purpose of our study was to evaluate the effect of PtCl4 on the antioxidant and enzymatic activity of duckweed (Lemna minor), a bioindicator of the aquatic environment. METHODS: The study was performed using a 7-day conventional test based on the OECD 221 (CSN EN ISO 20079)--Lemna sp. Growth Inhibition Test. We also conducted a microbiotest to analyse the effects of PtC4, PdCl2 and RhCl3 on the morphology and vegetative growth of colonies of this plant and compared their inhibitory effects during the microbiotest. RESULTS: We observed inhibition of colony growth and clear morphological changes. Antioxidant and enzymatic activities increased with platinum doses increased. The 168hEC50 of PtCl4 was 12.16 µM (95% confidence interval = 9.88-14.44) and the 168hEC50 of PdCl2 was 50.39 (95% confidence interval = 23.83-76.96). The greatest inhibition of growth by RhCl3 was observed at 25 µM. CONCLUSIONS: The obtained results suggest that L. minor phytotoxicity tests should be widely used in the biomonitoring.

The effects of dietary exposure to Magnéli phase titanium suboxide and titanium dioxide on rainbow trout (Oncorhynchus mykiss).

Magnéli phase titanium suboxides (Magnéli TiOx) are promising, novel materials with superior properties compared to TiO2, they are substoichiometric titanium oxides with the chemical formula TinO2n-1 (where n ≥ 1). In this study, for the first time, subchronic effects of dietary intake of Magnéli TiOx were evaluated and compared with TiO2 particles of similar size, in concentrations 0.1% and 0.01% of feed. The experiment consisted of 38 d of an exposition period and 14 d of a depuration period. Minor effects on plasma biochemical profile and morphological parameters were recorded. A reduced count of leukocytes was found in the blood of both Magnéli TiOx and TiO2 exposed fish, suggesting immunotoxic effects. Erythrocytosis was specific for Magnéli TiOx. Indices of oxidative stress, namely increased lipid peroxidation in liver, increased activity of superoxide dismutase in liver, kidney and gills and glutathione S-transferase (GST) in gills, as well as decreased activity of ceruloplasmin and GST in liver were found predominantly in fish exposed to TiO2. Histopathological examination revealed increased lipid-like vacuolation in the liver, the presence of hyaline droplets in renal tubules and multiplication of mucous glands in the epidermis in both tested substances and intestine damage in TiO2 groups. Overall, in Magnéli TiOx exposed groups, fewer adverse effects compared to TiO2 expositions were recorded. Their wider practical implementation in place of TiO2 is therefore beneficial.

Exposure to 17ß-Oestradiol Induces Oxidative Stress in the Non-Oestrogen Receptor Invertebrate Species Eisenia fetida.

BACKGROUND: The environmental impacts of various substances on all levels of organisms are under investigation. Among these substances, endocrine-disrupting compounds (EDCs) present a threat, although the environmental significance of these compounds remains largely unknown. To shed some light on this field, we assessed the effects of 17ß-oestradiol on the growth, reproduction and formation of free radicals in Eisenia fetida. METHODOLOGY/PRINCIPAL FINDINGS: Although the observed effects on growth and survival were relatively weak, a strong impact on reproduction was observed (50.70% inhibition in 100 µg/kg of E2). We further demonstrated that the exposure of the earthworm Eisenia fetida to a contaminant of emerging concern, 17ß-oestradiol (E2), significantly affected the molecules involved in antioxidant defence. Exposure to E2 results in the production of reactive oxygen species (ROS) and the stimulation of antioxidant systems (metallothionein and reduced oxidized glutathione ratio) but not phytochelatins at both the mRNA and translated protein levels. Matrix-assisted laser desorption/ionization (MALDI)-imaging revealed the subcuticular bioaccumulation of oestradiol-3,4-quinone, altering the levels of local antioxidants in a time-dependent manner. CONCLUSIONS/SIGNIFICANCE: The present study illustrates that although most invertebrates do not possess oestrogen receptors, these organisms can be affected by oestrogen hormones, likely reflecting free diffusion into the cellular microenvironment with subsequent degradation to molecules that undergo redox cycling, producing ROS, thereby increasing environmental contamination that also perilously affects keystone animals, forming lower trophic levels.