Acute Toxicological Effects Research Articles

Acute toxicological effects of zinc oxide nanoparticles in mice after intratracheal instillation.

Zinc oxide nanoparticles (ZnO NPs) are increasingly being used in industry. To evaluate the acute toxicology of ZnO NPs in Mice. ZnO NPs were intratracheally instilled into mice at different dose (200, 400, 800μg/kg), which was 1, 2, or 4 times of accumulative intake in one week according to the threshold limit value. Acute toxicity was assessed by animal mortality, organ/body weight ratios, hematology, blood biochemistry, and histopathology as well as by the determination of cells, proteins, and lactate dehydrogenase activity in bronchoalveolar lavage fluid. Exposure to ZnO NPs also resulted in bodyweight loss and a higher level of total cell number, total protein, and hydroxyproline content in BALF. Nitric oxide and malondialdehyde levels in the lung homogenates were also increased. In addition, inflammatory and hyperplastic changes in the lungs were observed. Threshold limit value (5mg/m3) may unfit for ZnO NPs.

Cytotoxic Effects of Salvinorin A, A Major Constituent of Salvia divinorum.

S. divinorum is a psychoactive plant that has been consumed as a recreational drug of abuse in the last years. Salvinorin A is its main constituent, and is responsible for the observed psychoactive effects. Both S. divinorum and salvinorin A have become controlled drugs in several countries, but they are not listed in the Schedules of the United Nations Drug Conventions. Regarding the effects of S. divinorum consumption, almost all studies are based on in vivo or on surveys, and there are no studies in vitro on its toxicity. Furthermore, all studies are focused on the acute toxicological effects of the plant. So, it is of utmost importance to further investigate the effects of S. divinorum and salvinorin A, particularly using in vitro models, after prolonged exposures. In this context, the present work evaluated the in vitro toxicity induced by S. divinorum or salvinorin A in six cell lines, through MTT assays and LC50 determination. Overall, results showed that both S. divinorum and salvinorin A are cytotoxic, dose- and time-dependent. Also, Hep G2 and Caco 2 (to a lesser extent) cells showed lower sensitivity to S. divinorum and salvinorin A when compared to the other studied cell lines. To our knowledge, this is the first work focused on the in vitro toxicity of S. divinorum and salvinorin A using a variety of cell lines, which are extensively described in literature and have been widely used in several in vitro studies.

Anti-inflammatory and toxicological evaluation of Moussonia deppeana (Schldl. & Cham) Hanst and Verbascoside as a main active metabolite

Ethnopharmacological relevanceMoussonia deppeana, known as Tlachichinole, is a Mexican medicinal plant used for treatment of inflammatory diseases, influenza, diarrhea, gastrointestinal disorders and arthritis. Aim of the studyIn this paper the antioxidant and anti-inflammatory activities as well as the acute and sub-acute toxicological effects were evaluated for the ethanolic extract from aerial parts of M. deppeana, also its phytochemical analysis is described. Materials and methodsPhytochemical analysis and compound isolation were performed with thin layer chromatography. The chemical identification of the main compound was performed by 1H NMR (COSY, NOESY, HSQC and HMBC) spectra. In vitro antioxidant capacity and total phenolic content for the ethanolic extract and its primary fractions was determined by DPPH and Folin-Ciocalteu reagent. Acute and subacute toxicity tests were evaluated on Balb/C mice. Finally acute anti-inflammatory evaluation was tested for a local (TPA) and systemic (carrageenan) murine model. ResultsThe main compound isolated from the ethanolic extract of M. deppeana was Verbascoside, which was isolated from F3 and was identified by 1H NMR and COSY data. Furthermore oleanolic and ursolic acids were isolated from primary fractions F1 and F2. Ethanolic extract showed IC50 = 6.71mg/mL for DPPH test and 664.12µg QE/mL for the total phenolic content. The LD50 value was >2g/kg by i.g. route in male and female mice. Sub-acute administration (28 days) of the ethanolic extract (1g/kg) did not cause lethality or alter any hematological and biochemical parameters, in addition, histological analysis of the major organs exhibited no structural changes. Anti-inflammatory activity of the ethanolic extract showed an ED50 = 1.5mg/ear and 450mg/kg for TPA and carrageenan test, respectively. Primary fractions generated moderate local and systemic anti-inflammatory activity. ConclusionThe ethanolic extract from the aerial parts of M. deppeana did not cause any lethality or adverse effect in either of the acute and sub-acute toxicity tests. This exhibited an important local and systemic anti-inflammatory activity and also moderate antioxidant capacity. Moreover, the primary fraction F2 was more active for the TPA model while the primary fraction F3 was most active in the carrageenan model in vivo. The main compound isolated from F3 was verbascoside; on the other hand also ursolic and oleanolic acids were isolated from F1 and F2.

Mycotoxins: cytotoxicity and biotransformation in animal cells.

Mycotoxins are secondary metabolites produced by many microfungi. Hitherto, over 300 mycotoxins with diverse structures have been identified. They contaminate most cereals and feedstuffs, which threaten human and animal health by exerting acute, sub-acute and chronic toxicological effects, with some considered as carcinogens. Many mycotoxins at low concentrations are able to induce the expression of cytochrome P450 and other enzymes implicated in the biotransformation and metabolization of mycotoxins in vivo and in vitro. Mycotoxins and their metabolites elicit different cellular disorders and adverse effects such as oxidative stress, inhibition of translation, DNA damage and apoptosis in host cells, thus causing various kinds of cytotoxicities. In this review, we summarize the biotransformation of mycotoxins in animal cells by CYP450 isoforms and other enzymes, their altered expression under mycotoxin exposure, and recent progress in mycotoxin cytotoxicity in different cell lines. Furthermore, we try to generalize the molecular mechanisms of mycotoxin effects in human and animal cells.

Evaluation of sesamol-induced histopathological, biochemical, haematological and genomic alteration after acute oral toxicity in female C57BL/6 mice.

The objective of this study was to evaluate organ-wise toxicological effects of sesamol and determine the LD50 cut-off value and GHS category following acute oral toxicity method OECD 423. An acute oral toxicity study was carried out in female C57BL/6 mice. Observations for physical behaviour and measurements on haematology, biochemistry, histology of vital organs were performed. In addition, genotoxicity assessment using comet and micronuclei assays was also performed. Acute toxicological effects were observed at 2000 mg/kg, while no adverse effects observed at 300 mg/kg. The effects of 2000 mg/kg were manifested as severe histopathological changes in all organs (femur, spleen, gastrointestine, lungs, heart, kidney, liver, stomach and brain) and excessive DNA strands breaks occurred in femoral bone marrow cells and splenocytes. A single dose of sesamol (2000 mg/kg, body weight) caused the death of two mice (out of three) within 2 h. Hence, sesamol is in GHS category 4 (>300–2000) with LD50 cut-off value of 500 mg/kg body weight. In contrast, this study is correlated with the obtained GHS category 4 and LD50 cut-off value 580 mg/kg body weight by ProTox. In conclusions, the present study has classified sesamol toxicity and assessed organ-wise acute oral toxicity of sesamol in female C57BL/6 mice. Therefore, these findings may be useful for the selection of dosages for further pre-clinical evaluation and potential drug developmental of sesamol.

The Protective Role of Datura Stramonium Leaves Ethanolic Extract Against Acute Carbaryl Toxicity in Rats

Background and objective: Two experiments were designed and performed in the present study in order to investigate the protective role of Datura stramonium leaves ethanolic extract against acute carbaryl toxicity in rats. Methods: The first experiment was designed to study the acute toxicological effects of Datura stramonium crude ethanolic extract and carbaryl in rats by determining the oral median lethal dose (LD50) using up and down method. The second experiment was isobolographic analysis that used to determine the sort of interaction of the plant extract & carbaryl alone & in combination.Results: The calculated median lethal dose (LD50) was (3185.25) mg/kg B.W. for ethanolic extract of Datura stramonium leaves & (328.5) mg/kg B.W. for carbaryl insecticide. The clinical signs were observed daily during the course of experiment, animal with toxic dose of carbaryl showed mainly cholinergic effect symptom, while those with toxic dose of Datura stramonium extract showed mainly anticholinergic effect symptom. The result of isobolographic analysis showed that the sort of interaction was highly antagonism .There was increase in the combined LD50 of carbaryl & Datura stramoinum extract nearly double that of each one alone , this was due to the plant contain high level of tropane alkaloids that abolish carbaryl cholinergic toxic effect by blocking the muscarinic receptors of parasympathetic nerve ending.Conclusion: Datura stramonium leaves extract shows highly protective effect against carbaryl cholinergic toxic effect in acute exposure in rats.

Comparing Acute Toxicity of Gunshot Particles, from Firing Conventional and Lead-Free Ammunition, in Pulmonary Epithelial Cell Cultures

Numerous studies demonstrated that the use of lead (Pb)-containing ammunition is associated with mainly chronic health problems and also is a burden on the environment and wildlife. Recently, a number of reports showed evidence of undesirable acute health effects related to the use of newly developed Pb-free small-caliber ammunition. In this study, particles from leaded and Pb-free ammunition were collected in liquid collection medium, in a highly controlled chamber, while firing a pistol (9 mm) or a rifle (7.62 × 51 mm). The emitted particles were typically smaller than 4 μm, with the great majority in even smaller size ranges, as shown by gravimetrical analysis and a multistage impactor. Chemical analysis revealed significant differences in content and concentration of several metals in the particles. After administration of the liquids to alveolar and bronchial in vitro cell systems, particles were taken up by the cells; the Pb-free particles displayed higher cytotoxicity (EC50 = 2 μg/cm2) than particles from Pb ammunition. High correlation factors (>0.9) were found between cell death and content of copper and zinc. Particles from both Pb-containing and Pb-free ammunition were able to induce oxidative stress and the proinflammatory marker interleukin (IL)-8 in both in vitro systems. These results support previous findings that indicate an association between gunshot emissions and metal fume fever. This study demonstrates the usefulness of combining chemical data with biological in vitro responses in assessing acute toxicological effects from emissions from firing both Pb and Pb-free ammunition.

Acute toxicological effects on the earthworm Eisenia fetida of 18 common pharmaceuticals in artificial soil

Following soil applications of recycled water and biosolids, pharmaceutical residues can eventually enter the terrestrial environment. In vitro and in vivo assays have largely focused on the acute ecotoxicity of these compounds in aquatic systems. However, studies on the ecotoxicological effects of pharmaceuticals in soil biota are especially scarce.The aim of this study was to investigate the acute toxicity of 18 pharmaceuticals (4 NSAIDs, 5 blood lipid-lowering agents, 6 β-blockers and 3 antibiotics) that are usually found in the environment by using an Eisenia fetida bioassay. In addition, the presence of these pharmaceuticals in artificial soil was verified at the end of the test.Our results indicate that seven of the studied drugs cause acute adverse effects in E. fetida, in particular, the NSAIDs and the blood lipid-lowering agents. Ibuprofen (LC50=64.80mg/kg) caused the highest acute toxicity for all tested compounds, followed by diclofenac (LC50=90.49mg/kg) and simvastatin (LC50=92.70mg/kg). Other tested pharmaceuticals from NSAIDs and blood lipid-lowering families have toxicity effects, from a LC50=140.87mg/kg for gemfibrozil to 795.07mg/kg for lovastatin. Atorvastatin, bezafibrate, β-blockers and antibiotics showed no detectable lethality in E. fetida. The four NSAIDs showed evidence of modification of their original chemical structure after 14days so the detected toxicity may be due to the original product as well as their degradation products. The three blood lipid-lowering agents seem to be more stable in soil.From an environmental perspective, the lethal concentrations of the tested drugs are much greater than those reported in wastewater and biosolids, therefore acute toxic effects may be improbable. However, little is known about the accumulation of these substances in soils after regular applications, so accumulative and chronic effects cannot be excluded. Moreover, more studies are needed to determine the role of the degradation products of these pharmaceuticals on terrestrial toxicity.

Synthesis and characterization of silica microsphere and their application in removal of uranium and thorium from water

Uranium (U) and thorium (Th) are known to cause acute toxicological effects in human, and their compounds are potential occupational carcinogens. During this work, silica microspheres were used to decontaminate the traces of U and Th in different water sources originated from groundwater and lake water. Ultra-filtration technique was used to isolate the microsphere from the water samples. Silica microspheres were synthesized based on a polyvinylpyrrolidone involved emulsion polymerization and subsequent sol–gel process. The microspheres were characterized for their size by using dynamic light scattering, and presence of silicate structure is verified by recording their attenuated total reflectance-Fourier transform infrared spectrum. The surface morphologies of the prepared silica microspheres were studied by using scanning electron microscope. Water samples collected from the groundwater and lake water were spiked with U and Th in the concentration range of 100–1,000 ng mL−1. The results of batch sorption experiments suggest that silica microsphere is very effective at pH 3, and sorption is more than 99.9 %. Equilibrium sorption follows Langmuir isotherms and the maximum U, and Th uptake is 30 and 36 mg g−1, respectively. Major physicochemical characteristics of the water were monitored before and after the decontamination process. Experimental results show no significant variations in any of the measured parameters.

A metabolic profiling analysis of the acute toxicological effects of the realgar (As2S2) combined with other herbs in Niuhuang Jiedu Tablet using 1H NMR spectroscopy

Ethnopharmacological relevanceNiuhuang Jiedu Tablet (NJT), composed of Realgar (As2S2), Bovis Calculus Artificialis, Borneolum Synthcticum, Gypsum Fibrosum, Rhei Radix et Rhizoma (RR), Scutellariae Radix (SR), Platycodonis Radix (PR) and Glycyrrhizae Radix et Rhizoma (GR), is an effective formula of traditional Chinese medicine (TCM) used in treating acute tonsillitis, pharyngitis, periodontitis and mouth ulcer. In the formula, significant level of realgar (As2S2) as a potentially toxic element is contained. In our pervious experiments, NJT was significantly less toxic than realgar (As2S2), and the material bases of toxicity alleviation effect to realgar (As2S2) were RR, SR, PR and GR. However, the toxicity alleviation effect of each above mentioned four herbs to realgar (As2S2) and their synergistic detoxification effects to realgar (As2S2) were still obscure. Materials and methodsMale Wistar rats were divided into 11 groups: control, group R (treated with Realgar), group RRSPG (treated with Realgar, RR, SR, PR and GR), group RRSP (treated with Realgar, RR, SR and PR), group RRSG (treated with Realgar, RR, SR and GR), group RRPG (treated with Realgar, RR, PR and GR), group RSPG (treated with Realgar, SR, PR and GR), group RR (treated with Realgar and RR), group RS (treated with Realgar and SR), group RP (treated with Realgar and PR) and group RG (treated with Realgar and GR). Based on 1H NMR spectra of urine and serum from rats, PCA and PLS-DA were performed to identify different metabolic profiles. Liver and kidney histopathology examinations and serum clinical chemistry analysis were also performed. ResultsThe metabolic profiles of groups RR, RS, RP and RG were similar to those of group R, while the metabolic profiles of groups RRSPG, RRSP, RRSG, RRPG and RSPG were almost in line with those of control group. Statistics results were confirmed by the histopathological examination and biochemical assay. ConclusionThe present work suggested that the toxicity alleviation effects of RR, SR, PR and GR to realgar (As2S2) were not obvious when combined with realgar (As2S2) respectively, but they had synergistic detoxification effects on realgar (As2S2) mutually.

Biological Effect of Di (p-methylbenzoyl) Diselenide (In-vitro) and Its Acute Hepatotoxicity on Rats (In-vivo).

Selenium plays an important role in biological system due to its incorporation in glutathione peroxidases and thioredoxin reductase as prosthetic group, the pharmacological studies of synthetic organoseleno-compounds revealed these molecules to be used as antioxidants, enzyme inhibitors, neuroprotectors, antitumor, anti-infectious agents, cytokine inducers and immuno-modulators. The present study was undertaken to elucidate Synthesis and biological effect Di (p-methylbenzoyl) diselenide (DMBDS) in-vitro. Di (p-methylbenzoyl) diselenide DMBDS was synthesized and its structure was confirmed by different spectroscopy techniques. In-vitro dose response of DMBDS on lipid peroxidation, nitrite content, GPx and arginase activities beside blood coagulation were measured. Acute toxicological effects were assessed by single orally injected Swiss albino mice with different DMBDS concentrations. In-vitro results revealed that DMBDS induces oxidative stress, elevation of arginase activity and acts as coagulant.

Evaluation of the toxicological profile of the leaves and young twigs of <i>Caesalpinia bonduc</i> (linn) roxb

Acute and sub-acute toxicological effects of ethanolic extract of the leaves and young twigs of Caesalpinia bonduc were carried out on albino rats. Single extract doses from 2000 to 5000 mg/kg body weight were administered orally and monitored for 14 days in acute study, while extract doses from 200 to 1600 mg/kg body weight were orally administered daily for 28 days in sub-acute study and recovery was assessed 14 days after dosing. Biochemical, haematological and histopathological examinations were carried out. There was no mortality in the experimental animals in all acute treatment doses. However, there were significant alterations in the biomarkers and induced cellular damage to the liver in all acute treatment doses. In the sub-acute toxicity treatment, the assessed biomarkers were unaffected at extract dose of 200 mg/kg body weight compared to control, while significant changes were observed in rats administered with extract doses of 400 mg/kg body weight and above. No significant difference was observed between the tested groups and the recovery groups in the sub-acute toxicity study. In conclusion, the ethanolic extract of C. bonduc could be toxic to selected organs of the rat body in acute and sub-acute treatments.

Acute Toxicological Effects of Suspended Solids on the Zooplankton

In this paper, the acute toxicity test was used to study the effects of different concentrations of suspended solids on the growth of zooplankton from Jiaozhou Bay. The experiment result showed that there had a significant impact of suspended solids on zooplankton growth and the mortality rate rose with the increasing concentration of suspended solids. The lethal concentration of 96h-LC50 was 60.172mg / L.

Pre-clinical pharmacokinetics and acute toxicological evaluation of a monastrol derivative anticancer candidate LaSOM 65 in rats

1. The present work investigated the pharmacokinetic and tissue distribution as well as acute toxicity of a new chemical entity (NCE), the anticancer candidate LaSOM 65 in Wistar rats.2. LaSOM 65 pharmacokinetics was investigated after intravenous (i.v., 1 mg/kg) and oral (p.o., 10 and 30 mg/kg) dosing. Tissue distribution was assessed after i.v. bolus dose. Acute toxicity was evaluated after i.v. (1, 2.5 and 5 mg/kg) and p.o. (50, 100 and 150 mg/kg) administration.3. Short half-life (1.75 ± 0.71 h), a clearance of 0.85 ± 0.18 L/h/kg and a volume of distribution of 1.76 ± 0.24 L/kg were observed after i.v. dosing. The compound showed good bioavailability and linear pharmacokinetics after oral doses. The NCE distributes consistently in lung and fatty tissues, with penetration ratios of 2.7 and 1.4, respectively. The other tissues investigated presented smaller penetration ratios. Adverse clinical symptoms were observed only after i.v. administration, and regressed 3 h after dosing. Compared with controls, no statistical differences were found for serum analysis, body weight and relative organ weight, indicating no acute toxicological effects.4. Overall, LaSOM 65 showed good pharmacokinetic characteristics and no signs of acute toxicity, indicating that it is a promising anticancer candidate.

Acute and Chronic Toxic Effects of Chloramphenicol on Scenedesmus Obliquus and Chlorella Pyrenoidosa

The acute and chronic toxicological effects of Chloramphenicol (CAP) on Scenedesmus obliquus and Chlorella pyrenoidosa are not well understood. The indoor experiments were carried to observe and analyze the CAP induced changes. Results of the observations have showed that CAP exposure could significantly inhibit the growth of Scenedesmus obliquus in almost all the treated groups, while Chlorella pyrenoidosa exhibited less sensitivity. Chlorophyll-a syntheses of Scenedesmus obliquus were all inhibited by CAP exposure, while Chlorella pyrenoidosa displayed obvious stimulation effect. Catalase (CAT) and Superoxide dismutase (SOD) activities of both algae were promoted in all the treatments. The experimental results indicated that the growth and Chlorophyll-a syntheses of Scenedesmus obliquus were more sensitive in response to CAP exposure than that of Chlorella pyrenoidosa. While for CAT and SOD activities, Chlorella pyrenoidosa showed more susceptible. This research provides a basic understanding of CAP toxicity to aquatic organisms.

Emerging mechanistic targets in lung injury induced by combustion-generated particles.

The mechanism for biological effect following exposure to combustion-generated particles is incompletely defined. The identification of pathways regulating the acute toxicological effects of these particles provides specific targets for therapeutic manipulation in an attempt to impact disease following exposures. Transient receptor potential (TRP) cation channels were identified as "particle sensors" in that their activation was coupled with the initiation of protective responses limiting airway deposition and inflammatory responses, which promote degradation and clearance of the particles. TRPA1, V1, V4, and M8 have a capacity to mediate adverse effects after exposure to combustion-generated particulate matter (PM); relative contributions of each depend upon particle composition, dose, and deposition. Exposure of human bronchial epithelial cells to an organic extract of diesel exhaust particle was followed by TRPV4 mediating Ca(++) influx, increased RAS expression, mitogen-activated protein kinase signaling, and matrix metalloproteinase-1 activation. These novel pathways of biological effect can be targeted by compounds that specifically inhibit critical signaling reactions. In addition to TRPs and calcium biochemistry, humic-like substances (HLS) and cell/tissue iron equilibrium were identified as potential mechanistic targets in lung injury after particle exposure. In respiratory epithelial cells, iron sequestration by HLS in wood smoke particle (WSP) was associated with oxidant generation, cell signaling, transcription factor activation, and release of inflammatory mediators. Similar to WSP, cytotoxic insoluble nanosized spherical particles composed of HLS were isolated from cigarette smoke condensate. Therapies that promote bioelimination of HLS and prevent the disruption of iron homeostasis could function to reduce the harmful effects of combustion-generated PM exposure.

Novel Psychoactive Substances

Since the turn of the 21st century, there has been an increase in the availability and use of novel psychoactive substances (also known as "legal highs") across Europe. Currently, there is limited information available on the potential acute toxicity (harms) associated with the use of these novel psychoactive substances. There are a number of potential data sources that can provide information on the acute toxicity associated with their use: (1) user reports on Internet discussion fora; (2) subpopulation level surveys of self-reported harms/unwanted effects (3) regional or national poisons information service accesses for support on presentations to healthcare facilities relating to acute toxicity; (4) case reports/series based on self-reported use or analytically confirmed use; and (5) human volunteer studies assessing potential acute toxicological effects. Each of these data sources has its own limitations, particularly those that are based on self-reported use because there are a number of European studies that show that there is inconsistency in the substance(s) in the "drug" that an individual uses. However, by using a multilayered approach of combining different sources, it is possible to reduce the overall impact of the limitations of any one individual data source. In this review article, we will combine information from these different data sources to describe the pattern of acute toxicity associated with 4 novel psychoactive substances: 1-benzylpiperazine, mephedrone (4-methylmethcathinone), synthetic cannabinoid receptor agonists, and methoxetamine.

Nonclinical Toxicological Evaluation of Occidiofungin, a Unique Glycolipopeptide Antifungal

Occidiofungin, a glycolipopeptide obtained from the liquid culture of Burkholderia contaminans MS14, has been identified as a novel fungicide. The present study was designed to initially assess the in vitro toxicity in a rat hepatoma (H4IIE) cell line and acute toxicological effects of occidiofungin using a mouse model. In vitro toxicity was observed in all variables at 5 μmol/L. B6C3F1 mice were given single and repeat doses of occidiofungin up to 20 mg/kg. Key effects were a reduction in body and organ weights. However, no significant decrease in body weight was noted at a dose of 1 mg/kg, which is comparable to the dose level of other cyclic glycopeptide antifungal agents currently approved for human use. Microscopic examination of treated mice did not identify any signs of organ-specific toxicity at the dose levels tested.

Titanium Dioxide Nanoparticles-Mediated In Vitro Cytotoxicity Does Not Induce Hsp70 and Grp78 Expression in Human Bronchial Epithelial A549 Cells

Titanium dioxide nanoparticles (TiO(2)NPs) are increasingly being used in various industrial applications including the production of paper, plastics, cosmetics and paints. With the increasing number of nano-related products, the concern of governments and the general public about the health and environmental risks, especially with regard to occupational and other environmental exposure, are gradually increasing. However, there is insufficient knowledge about the actual affects upon human health and the environment, as well as a lack of suitable biomarkers for assessing TiO(2)NP-induced cytotoxicity. Since the respiratory tract is likely to be the main exposure route of industrial workers to TiO(2)NPs, we investigated the cytotoxicity of the anatase and rutile crystalline forms of TiO(2)NPs in A549 cells, a human alveolar type II-like epithelial cell line. In addition, we evaluated the transcript and protein expression levels of two heat shock protein (HSP) members, Grp78 and Hsp70, to ascertain their suitability as biomarkers of TiO(2)NP-induced toxicity in the respiratory system. Ultrastructural observations confirmed the presence of TiO(2)NPs inside cells. In vitro exposure of A549 cells to the anatase or rutile forms of TiO(2)NPs led to cell death and induced intracellular ROS generation in a dose-dependent manner, as determined by the MTS and dichlorofluorescein (DCF) assays, respectively. In contrast, the transcript and protein expression levels of Hsp70 and Grp78 did not change within the same TiO(2)NPs dose range (25-500 μg/ml). Thus, whilst TiO(2)NPs can cause cytotoxicity in A549 cells, and thus potentially in respiratory cells, Hsp70 and Grp78 are not suitable biomarkers for evaluating the acute toxicological effects of TiO(2)NPs in the respiratory system.

Eco-toxicological effect of Carbamazepine on Scenedesmus obliquus and Chlorella pyrenoidosa

The acute and chronic toxicological effects of Carbamazepine (CBZ) on Scenedesmus obliquus and Chlorella pyrenoidosa were explored for the first time in this study. The results showed that CBZ could significantly inhibit the growth of the two algae in almost all treatment groups. EC50 values indicated that, CBZ had a relatively limited acute toxic effect (0–144h) on S. obliquus and C. pyrenoidosa, while, chronic tests (5–30d) displayed higher toxicity. Chlorophyll a syntheses were nearly all inhibited by CBZ exposure. However, superoxide dismutase (SOD) and catalase (CAT) activities in acute tests of both algae were markedly promoted. According to the results, Chlorophyll a content and CAT activity of S. obliquus were more sensitive to CBZ than that of C. pyrenoidosa. While for SOD, quite to the contrary, C. pyrenoidosa was more vulnerable. We obtained a similar result in chronic tests. This research furthers our understanding of CBZ toxicity to aquatic organisms.