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1.
J Hazard Mater ; 382: 121066, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31473515

RESUMO

Microplastics (MPs) are critical emerging pollutants found in the environment worldwide; however, its toxicity in aquatic in amphibians, is poorly known. Thus, the aim of the present study is to assess the toxicological potential of polyethylene microplastics (PE MPs) in Physalaemus cuvieri tadpoles. According to the results, tadpoles' exposure to MP PE at concentration 60 mg/L for 7 days led to mutagenic effects, which were evidenced by the increased number of abnormalities observed in nuclear erythrocytes. The small size of erythrocytes and their nuclei area, perimeter, width, length, and radius, as well as the lower nucleus/cytoplasm ratio observed in tadpoles exposed to PE MPs confirmed its cytotoxicity. External morphological changes observed in the animal models included reduced ratio between total length and mouth-cloaca distance, caudal length, ocular area, mouth area, among others. PE MPs increased the number of melanophores in the skin and pigmentation rate in the assessed areas. Finally, PE MPs were found in gills, gastrointestinal tract, liver, muscle tissues of the tail and in the blood, a fact that confirmed MP accumulation by tadpoles. Therefore, the present study pioneering evidenced how MPs can affect the health of amphibians.

2.
Sci Total Environ ; 700: 134867, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31706091

RESUMO

Different studies have reported the ecotoxicological effects of polyethylene microplastics (PE MPs) on aquatic organisms; however, little is known about their toxicity in the early life stages of aquatic vertebrates living in freshwater ecosystems. Thus, the aim of the current study is to evaluate the toxicity of PE MPs throughout the development of Danio rerio after their static and semi-static exposure to different concentrations of these pollutants (6.2, 12.5, 25, 50 and 100 mg/L) - models were monitored at different time-periods, namely: 24, 48, 72, 96, 120 and 144 h. Based on the collected data, small PE MP concentrations have harmful effects on D. rerio embryos and larvae; the magnitude and characteristics of these effects depend on the adopted exposure system, which can be static or semi-static. PE MPs had negative effect on embryos' hatching rate in both exposure systems. However, the early hatching observed during the exposure through the static system could explain the lower larval survival rate after egg hatching. Nevertheless, PE MPs induced significant changes in various morphometric parameters. The present study is the first to assess the addressed topic; therefore, it is recommended to carry out future investigations to broaden the knowledge about PE MP toxicity.

3.
Sci Total Environ ; 689: 381-389, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31277005

RESUMO

There are several reports on the damage smoking causes to human health available in the literature, but little is known about the environmental and biological consequences from inappropriate cigarette butt (CB) disposal in urban and natural environments. The immunotoxic, morphotoxic and mutagenic potential of leachates from cigarette butts (LCB) diluted at environmentally relevant rates (LCB1x: 1.375%; LCB10x: 13.75%) was evaluated in adult representatives of the bivalve species Anodontites trapesialis, which was adopted as model organism. Type II hyalinocytes and granulocytes (phagocytic cells) frequency increased in the hemolymph of subjects exposed to the pollutant for 14 days. Based on this outcome, LCB chemical constituents did not induce immunotoxic effects. The treatments also did not seem to have any impact on the subjects' hemocitary morphometry parameters: diameter, area, perimeter, circularity and nucleus - cytoplasm ratio. However, subjects in groups LCB1x and LCB10x recorded a larger number of hyalinocytes with some nuclear abnormality such as micronucleus, blebbed nucleus, asymmetric constriction nucleus, and nuclear multilobulation and binucleation. The association between these abnormalities and the treatments was confirmed by the Cr, Ni, Pb, Zn, Mn and Na bioaccumulation in tissue samples of the bivalve models exposed to LCB. To the best of our knowledge, this is the first report on LCB mutagenicity in representatives of a freshwater bivalve group. Given the chemical complexity of the addressed pollutants, it is imperative to develop further investigations about the topic.

4.
Chemosphere ; 235: 556-564, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31276868

RESUMO

Understanding how human activities affect animal biodiversity is essential to investigations about the biological effects of several pollutants and contaminants dispersed in the environment. This is the case of zinc oxide nanoparticles (ZnO NPs), which are emerging pollutants whose effect on reptiles' health is completely unknown. Thus, the objective of the present study is to evaluate the possible damages induced by these NPs in Podocnemis expansa juveniles (Amazon turtle) by using morphological changes of circulating erythrocytes as nuclear toxicity biomarker. The animals were exposed to the intramuscular administration of 440 µg/kg and 440,000 µg/kg of ZnO NPs, for 10 consecutive days. The micronuclei assay and other nuclear abnormalities were performed at the end of the experiment, as well as different morphometric measurements applied to the erythrocytes. Based on the current data, ZnO NPs induced nuclear abnormalities such as micronuclei and binucleation, which are associated with carcinogenic processes and with flaws in the mitotic machinery. The low "nuclear area: erythrocyte area" ratio and larger cytoplasmic area observed for animals exposed to NPs evidenced erythrocytic change induction likely related to negative energy balance/metabolism interferences and/or to oxygen transportation efficiency by erythrocytes. This is the first report on the mutagenic and cytotoxic effect induced by NPs on representatives of a group of reptiles. This outcome suggests that further investigations must focus on better understanding the (eco)toxicological potential of ZnO NPs.

5.
Sci Total Environ ; 685: 923-933, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247439

RESUMO

The ecotoxicity of untreated tannery effluent (UTE) in several animal models has been reported; however, its effects on fish behavior, and neurotoxicity, remain unknown. Thus, the hypothesis that the chronic exposure to UTE can induce behavioral changes in adult zebrafish (Danio rerio) representatives, even when it is highly diluted in water, was tested. Animals exposed to 0.1% and 0.3% UTE for 30 days showed behavioral changes in visual social preference tests through their co-specific and antipredator defensive responses, which had indicated neurotoxic actions. Zebrafish exposed to UTE appeared to have not co-specific preference when it is paired with Poecilia sphrenops. In addition, only animals in the control group showed aversive behavior in the presence of the herein used predatory stimulus (Oreochromis niloticus). However, Cr, Na and Mg bioaccumulation was higher in zebrafish exposed to 0.1% and 0.3% UTE, although anxiogenic and anxiolytic effects were not observed in the models exposed to UTE in the novel tank diving or aggressiveness-increase-in-the-mirror tests. This outcome allowed associating the exposure to the pollutant and bioaccumulation with the observed behavioral changes. The present study is pioneer in scientifically evidencing the sublethal impact caused by chronic exposure to UTE in experimental environment simulating realistic aquatic pollution conditions. Accordingly, results in the current research should motivate further investigations to broaden the knowledge about the real magnitude of UTE biological impacts on the aquatic biota.


Assuntos
Comportamento Animal/efeitos dos fármacos , Resíduos Industriais , Curtume , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Modelos Biológicos , Testes de Toxicidade
6.
Chemosphere ; 234: 379-387, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31228840

RESUMO

The toxicity caused by smoking to human health has been demonstrated in several scientific studies. However, little attention has been given to damages caused to aquatic biota when cigarette butts (CB) are disposed of on water surface. Thus, the main aim of the current study is to evaluate the behavioural toxicity of cigarette butt leachates (CBL) in freshwater bivalve species Anodontites trapesialis exposed to different environmentally-relevant dilutions (CBL1x = 1.375%, CBL10x: 13.75%). There were significant CBL effects on the burrowing performance of the evaluated bivalves, after 14 exposure days. Animals exposed to CBL presented higher latency to foot emission and to start the burrowing process, as well as larger number of cycles required for burial. In addition, there were lower burrowing angle and burrowing rate index in CBL-exposed bivalves than in the unexposed ones. Chemical analyses performed on the muscle tissues of animals exposed to both CBL dilutions evidenced the bioaccumulation of several metals at high concentrations in CBL (Cr, Ni, Pb, Mn, Zn and Na); this outcome enabled associating these metals with behavioural changes observed in CBL-exposed groups. Thus, the current study firstly reports that even highly-diluted CBL concentrations can induce behavioural changes in freshwater bivalves, as well as that CBL extrapolation to natural environments can lead to several damages to the fitness of living organisms and to the dynamics of their population.

7.
Sci Total Environ ; 681: 275-291, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31103665

RESUMO

Tannery industries generate large amounts of tannery effluents (TE), which have been considered highly toxic to various groups of animals. However, the identification and characterization of the impact of this mix of pollutants on birds is still highly incipient. So, our goal was to evaluate the possible biological changes of Coturnix coturnix japonica, exposed for 45 days, to different dilutions of TE (1.4%, 3.1% and 6.5%), using behavioural biomarkers, mutagenics and egg production. When submitted to the behavioural tests, quails that ingested TE presented behaviour compatible with an anxiolytic effect in the open field test; absence of emotional reactivity in the object recognition test; reduced rates of predation of Tenebrio molitor larvae (potential prey); as well as an anti-predatory defensive response deficit when confronted, especially with Felis catus males (potential predator). In addition, we observed increased biomass of the liver, increased feed conversion index and lower feed efficiency index; mutagenic effect of TE (inferred by the increase of nuclear erythrocyte abnormalities); reduced productive performance and egg quality, in addition to different staining patterns of the eggs produced by quails from the control group. Therefore, our study confirms the toxicity of TE in C. coturnix japonica, even in small dilutions. While behavioural changes demonstrate the neurotoxic potential of the pollutant, the other alterations suggest that the mechanisms of action of its chemical constituents are not selective, that is, they act systemically, acting synergistic, antagonistic or additively, causing harmful effects in animals.


Assuntos
Coturnix/fisiologia , Monitoramento Ambiental , Curtume , Testes de Toxicidade , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade , Animais
8.
Chemosphere ; 231: 10-19, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31128343

RESUMO

Although the toxicity of zinc oxide (ZnO) nanoparticles (NPs) is known in several experimental models, little is known about their effects on bird representatives. Therefore, the aim of the current study is to evaluate the mutagenic and cytotoxic potential of ZnO NPs in chicks belonging to species Gallus gallus domesticus, as well as to analyze the role played by nuclear and erythrocyte morphological changes as biomarkers of the toxicity of these nanopollutants. Two doses of ZnO NPs (0.245 mg k-1 and 245.26 mg kg-1) were herein tested; they were determined based on the predictive environmental concentration of these NPs (760 µg L-1), on the body biomass of the analyzed animals and on the mean daily water intake/bird. Birds were subjected to two intraperitoneal applications (one per day) of solution containing ZnO NPs; they were euthanized 48 h after the first application. The herein collected data have shown that NPs were capable of inducing the formation of different types of erythrocyte nuclear abnormalities, such as micronucleus, binucleate erythrocytes, blebbed, reniform and multilobulated nuclei, as well as symmetric and asymmetric constriction. In addition, changes in the size and shape of erythrocytes were observed in birds exposed to ZnO NPs. Zn bioaccumulation analysis conducted in brain tissues confirmed the association between these changes and animal exposure to ZnO NPs. Thus, besides confirming the toxicological potential of ZnO NPs, to the best of our knowledge, the current study is the first report on the mutagenic and cytotoxic effects of these NPs on bird representatives.


Assuntos
Núcleo Celular/patologia , Eritrócitos/patologia , Nanopartículas Metálicas/toxicidade , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Animais , Galinhas , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Codorniz , Poluição da Água/efeitos adversos
9.
Sci Total Environ ; 682: 561-571, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31128370

RESUMO

The toxicity of zinc oxide nanoparticles (ZnO NPs) has been investigated in different animal models. However, concentrations tested in most studies are often much higher than the ones potentially identified in the environment. Therefore, such toxicity limits the application of these studies to evaluate ecotoxicological risks posed by these nanopollutants. Thus, the aim of the current study is to evaluate the impacts of ZnO NPs (at environmentally relevant concentrations - 760 µg/L and 76,000 µg/L, for 72 h) on the behavioral responses of Oreochromis niloticus (Nile tilapia) exposed to it. Results did not evidence harmful effects of NPs on animals' locomotor abilities (evaluated through open-field and light-dark transition tests), or anxiety-predictive behavior. On the other hand, Zn bioaccumulation in the body tissues of the analyzed tilapias was correlated to changes in eating behavior (motivated by ration pellets), as well as to deficits in antipredatory defensive behavior (under individual and collective conditions). Tilapia exposed to ZnO NPs recorded lower avoidance, flight and territorialist behavior rates when they were individually confronted with potential predators (Salminus brasiliensis). However, collectively exposed animals were unable to recognize their predators, as well as to differentiate them from artificial baits ("false predators"). The present study is the first to report biological impacts resulting from the short exposure of fish-group representatives to ZnO NPs. Thus, we believe that it may be relevant to improve the knowledge about ecotoxicological risks posed by these pollutants.


Assuntos
Ciclídeos/fisiologia , Nanopartículas Metálicas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Animais , Ecotoxicologia , Nanopartículas/toxicidade , Testes de Toxicidade
10.
Environ Sci Pollut Res Int ; 26(11): 10641-10650, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30771127

RESUMO

The advent of biotechnology provided the synthesis of nanoproducts with diverse applications in the field of medicine, agriculture, food, among others. However, the toxicity of many nanoparticles (NP) currently used, which can penetrate natural systems and impact organisms, is not known. Thus, in this study, we evaluated whether the short exposure (5 days) to low concentrations of chitosan-coated zein nanoparticles (ZNP-CS) (0.2 ng/kg, 40 ng/kg, and 400.00 ng/kg) was capable of causing behavioral alterations compatible with cognitive deficit, as well as anxiety and depression-like behavior in Swiss mice. However, we observed an anxiogenic effect in the animals exposed to the highest ZNP-CS concentration (400.00 ng/kg), without locomotor alterations suggestive of sedation or hyperactivity in the elevated plus maze (EPM) test. We also observed that the ZNP-CS caused depressive-like behavior, indicated by the longer immobile time in the tail suspension test and the animals exposed to ZNP-CS presented deficit in recognition of the new object, not related to locomotor alteration in this test. To the best of our knowledge, this is the first report of the neurotoxicity of ZNP in a mammal animal model, contributing to the biological safety assessment of these nanocomposites.


Assuntos
Ansiedade/etiologia , Comportamento Animal/efeitos dos fármacos , Quitosana/química , Depressão/etiologia , Transtornos da Memória/etiologia , Nanopartículas/toxicidade , Zeína/toxicidade , Animais , Ansiedade/psicologia , Depressão/psicologia , Masculino , Transtornos da Memória/psicologia , Camundongos , Nanopartículas/química , Zeína/química
11.
Environ Sci Pollut Res Int ; 26(6): 6234-6243, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30637546

RESUMO

Antineoplastic drugs (AD) have been increasingly used, but the disposal of their wastes in the environment via hospital effluent and domestic sewage has emerged as an environmental issue. The current risks posed to these animals and effects of pollutants on the reptiles' population level remain unknown due to lack of studies on the topic. The aim of the present study was to evaluate the mutagenicity of neonate Podocnemis expansa exposed to environmental concentrations (EC) of cyclophosphamide (Cyc). The adopted doses were EC-I 0.2 µg/L and EC-II 0.5 µg/L Cyc. These doses correspond to 1/10 and » of concentrations previously identified in hospital effluents. Turtles exposed to the CyC recorded larger total number of erythrocyte nuclear abnormalities than the ones in the control group after 48-h exposure. The total number of abnormalities for both groups (EC-I and EC-II) 96 h after the experiment had started was statistically similar to that of animals exposed to high Cyc concentration (positive control 5 × 104 µg/L). This outcome confirms the mutagenic potential of Cyc, even at low concentrations. On the other hand, when the animals were taken to a pollutant-free environment, their mutagenic damages disappeared after 240 h. After such period, their total of abnormalities matched the basal levels recorded for the control group. Therefore, our study is the first evidence of AD mutagenicity in reptiles, even at EC and short-term exposure, as well as of turtles' recovery capability after the exposure to Cyc.


Assuntos
Ciclofosfamida/toxicidade , Mutagênicos/toxicidade , Tartarugas , Poluentes Químicos da Água/toxicidade , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/toxicidade , Relação Dose-Resposta a Droga , Ecotoxicologia/métodos , Eritrócitos/efeitos dos fármacos , Eritrócitos/patologia , Testes para Micronúcleos , Mutagênicos/administração & dosagem , Esgotos/química , Poluentes Químicos da Água/administração & dosagem
12.
Sci Total Environ ; 650(Pt 2): 2284-2293, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30292121

RESUMO

Cyclophosphamide (Cyc) and 5-fluorouracil (5-FU) are two of the most used antineoplastic drugs (AD) in the world. However, their discharge in the environment became a yet-unknown environmental issue that has impact on some groups of animals, such as amphibians. We assessed tadpoles (Lithobates catesbeianus) exposed to environmental concentrations (EC) of Cyc and 5-FU to evaluate whether they can cause morphological and mutagenic changes in them. We defined the following groups: control, positive control (50 mg/L of Cyc), EC-Cyc-I (0.2 µg/L), EC-Cyc-II (0.5 µg/L), EF-Cyc (2.0 µg/L), EC-5-FU-I (13.0 µg/L), EC-5-FU-II (30.4 µg/L) and EF-5-FU (123.5 µg/L). EC groups presented predictive AD concentrations in 10% and 25% hospital-effluent dilutions in water. EF groups met gross hospital-effluent concentrations. Based on our data, ADs caused intestinal changes and influenced the interocular distance in tadpoles after 30-day exposure. We also observed the aneugenic and clastogenic effect of ADs due to the higher frequency of micronucleated and binucleated erythrocytes, and blebbed, multilobulated, notched and kidney-shaped nuclei in animals exposed to them. Based on such changes, we assume that Cyc and 5-FU can trigger malignant cell transformation processes, and cancer, in animals exposed to them, even at low concentrations. Our study is the first to describe that Cyc and 5-FU, spread in the environment, cause damages in non-target organisms opposite to their original end.


Assuntos
Antineoplásicos/toxicidade , Ciclofosfamida/toxicidade , Fluoruracila/toxicidade , Larva/efeitos dos fármacos , Rana catesbeiana , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Testes para Micronúcleos
13.
Artigo em Inglês | MEDLINE | ID: mdl-30460649

RESUMO

Smoked cigarette butt (SCB) discharged in the environment became an issue of unknown consequences for plants. Thus, we aim at assessing the impact of water containing SBC leachate on the meristem cells of Allium cepa roots. We defined the following experimental groups: negative control (water), positive control (cyclophosphamide); water with SCB leachate at environmental concentration (1.9 µg/L of nicotine) (EC1× group) and water with SCB leachate concentration 1000 times higher than EC1 (EC1000× group). Mitotic index, total number of abnormal cells, index of abnormal cells per mitotic/phase, relative growth index, and inhibition index were calculated after 48 exposure hours. Root meristems were used to prepare slides in order to investigate chromosomal and nuclear abnormalities. According to our data, plants exposed to SCB leachate presented low relative growth index, high inhibition index, large number of abnormal cells, and high abnormality frequency at metaphase/anaphase. The exposed A. cepa recorded a wide variety of abnormalities such as diagonal metaphase/anaphase, metaphase/anaphase presenting chromosome fragments, binucleated cells, displaced nucleus, chromosome bridges, micronuclei, necrotic cells, stick metaphase, chromosome adherence, notched nucleus, among other cell disturbances. The chemicals in the SBC leachate had aneugenic and clastogenic effect on the genetic material of the tested plants, either when they acted individually, synergistically, or additively. Thus, our study is a pioneer in reporting that the mere disposal of cigarette butts in the environment can have cytotoxic, genotoxic, and mutagenic effects on plants.

14.
Artigo em Inglês | MEDLINE | ID: mdl-30411290

RESUMO

The increasing consumption of medications by humans has negative effects such as the increased disposal of these compounds in the environment. Little is known about how the disposal of a "drug mix" (DM) in aquatic ecosystems can affect their biota. Thus, we evaluated whether the exposure of Lithobates casteibeianus tadpoles to a DM composed of different medication classes (antibiotic, anti-inflammatory, antidepressant, anxiolytic, analgesic, and antacid drugs)-at environmentally relevant concentrations-may change their oral morphology, trigger behavioral disorders, and have mutagenic effects on erythrocyte cells. Based on our data, animals exposed to the DM showed changes in mandibular sheath pigmentation, dentition, and swimming activity, as well as atypical behavior in the social aggregation test [with co-specific and interspecific (Physalaemus cuvieri) individuals] and antipredatory defensive response deficit (chemical stimulus from Odonata larvae), after 15 exposure days. The mutagenic analysis revealed higher frequency of nuclear abnormalities in the erythrocytes of tadpoles exposed to the DM (e.g., multilobulated, blebbed, kidney-shaped, notched nucleus, binuclear, and micronucleated erythrocytes). Given the chemical complexity of the DM, we assumed that several organic functions may have been affected, either by the isolated, synergistic, antagonistic, or additive action of DM compounds. Finally, our study confirms the toxicological potential of DM in L. catesbeianus tadpoles, with emphasis to impacts that can affect the fitness of individuals and their natural populations. Thus, we suggest that more attention should be given to the disposal of medications in the environment and reinforce the need of improving water and sewage treatment systems.

15.
Environ Sci Pollut Res Int ; 25(36): 36355-36367, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30368706

RESUMO

Although the toxic effects of tannery effluent (TE) on tanning-industry workers have been reported in many studies, its effects on females' reproductive system are unknown. We aimed at evaluating the effects of direct contact with TE on the "emotional" status, estrous cycle (during 15 consecutive exposure days), and ovarian follicular dynamics of female Swiss mice at the end of the experiment to broaden the knowledge about the toxicity of this pollutant. The herein adopted exposure protocol simulated tanning-industry workers' exposure to TE. The test animals were subjected to 45 exposure days, for 1 h a day, 5 days a week (from Monday to Friday). Based on the collected data, female mice exposed to TE recorded high anxiety index in the elevated plus maze test, although we did not observe changes in their estrous cycle. The smaller total and specific number of ovarian follicles (types 1 to 6) and the higher frequency of degenerating follicles (atresic) in female mice exposed to TE marked the folliculogenesis reduction in them. Therefore, our study was the first to provide evidences that the exposure to TE can cause reproduction issues in female mice, as well as the first experimental insight about the impact of unhealthy work activities in tanning industries on women's reproductive system.

16.
Environ Sci Pollut Res Int ; 25(31): 31762-31770, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30242651

RESUMO

Although the efficiency of haloxyfop-p-methyl ester (HPME) as selective herbicide is acknowledged, its impact on non-target organisms is poorly known. It is not known whether the short exposure of mammals to low HPME concentrations (consistent with a realistic contamination scenario) poses risks to these animals. Thus, the aim of the current study is to evaluate the effects of HPME on the anti-predatory behavior of female Swiss mice exposed to it. The animals were divided in groups: non-exposed (control) and exposed (route: i.p., for 2 days) to different herbicide concentrations (2.7 × 10-4 g/kg and 2.7 × 10-2 g/kg of body weight), which were considered environmentally relevant predicted concentrations. The animals were subjected to the open field and elevated plus-maze tests; results showed that the HPME did not lead to anxiolytic or anxiety behavior, or to locomotive changes in the tested animals, fact that was confirmed through the Basso Mouse Scale for locomotion scores. On the other hand, animals exposed to the herbicide were incapable of recognizing the snake as potential predator. Animals in the control group, exposed to a real snake (Pantherophis guttatus) remained longer in the safety zone of the test device, presented lower frequency of self-grooming behaviors for a shorter period-of-time, besides showing longer freezing time, which was not observed in animals exposed to HPME. Therefore, our study indicates the ecotoxicological potential of the herbicide, since anti-predatory behavior disorders may affect preys' responses and population dynamics.

17.
Environ Sci Pollut Res Int ; 25(30): 30728-30736, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30220066

RESUMO

Although the toxicity of the pesticide sulfentrazone in some aquatic organisms is known, its effects on edaphic organisms such as earthworms remain completely unknown. Thus, we aimed at evaluating the behavior and immune response of Eisenia fetida exposed to sulfentrazone at environmentally relevant concentrations (EC). E. fetida representatives exposed to this contaminant (for 48 h) were divided in the following groups: environmental concentration (EC1x: 318 ng sulfentrazone/g of dry weight soil) and EC100x (concentration 100 times higher than in EC1x). Based on the avoidance test results, earthworms responded to this pesticide and proved the toxicity of sulfentrazone. The observed immune response induction was expressed by increased granulocytes presenting phagocytic vacuoles and agglomerations/encapsulations, mainly in animals belonging to groups EC1x and EC100x. However, the reduced frequency of plasmocytes in these animals' hemolymphs suggested that the phagocytic immune response was not efficient to assure 100% survival. Our study is the first to report sulfentrazone toxicity in an edaphic organism, at environmental concentration.

18.
Environ Pollut ; 242(Pt B): 1274-1282, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30121481

RESUMO

The toxicity of ZnO nanoparticles (NPs) has been the subject of several investigations; however, concentrations much higher than the ones potentially found in the environment are often tested. In addition, groups of animals such as birds have not been used as model in studies in this field, fact that creates an important ecotoxicological gap in them. The aim of the present study is to investigate the effects of the exposure to environmentally relevant concentrations of ZnO nanoparticles on the anti-predatory behavior of chicks (Gallus gallus domesticus). The test animals were daily exposed to an environmentally relevant concentration of ZnO nanoparticles (0.245 mg kg-1) and to a toxic concentration of it (245.26 mg kg-1) through intraperitoneal injection for two days. We set a control group for comparison purposes. According to our results, ZnO nanoparticles did not affect the locomotor activity of, and did not cause anxiolytic or anxiogenic effect on, birds in the open field test. However, based on the lowest cluster score recorded during the social aggregation test, chicks exposed to ZnO nanoparticles failed to recognize the grunt of a hawk (Rupornis magnirostris) as predatory threat. Only birds in the control group recognized the test snake (Pantherophis guttatus) as potential predator. The higher Zn concentration in the brains of animals exposed to ZnO nanoparticles evidenced the capacity of these nanomaterials to cross the blood-brain barrier, even at low concentrations. This blood-brain barrier crossing could have affected the structures or neuronal mechanisms that modulate the defensive response of birds. Assumingly, even the minimal exposure to low concentrations of ZnO nanoparticles can affect birds. Our outcomes corroborate previous studies about the biological risks of water surface contamination by metal-based nanomaterials.


Assuntos
Comportamento Animal/efeitos dos fármacos , Galinhas/fisiologia , Locomoção/efeitos dos fármacos , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Exposição Ambiental/efeitos adversos , Masculino
19.
Sci Total Environ ; 636: 1553-1564, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29913616

RESUMO

Abamectin (ABA) toxicity in fish, amphibian and mammals was already proven, but its effect on birds is almost unknown. Thus, the aim of our study is to assess the impact of exposure to water with ABA for 40 days at predicted environmentally relevant concentrations on the behavior of female Japanese quails (Coturnix coturnix japonica). The three following experimental groups (n = 10 each) were set: "control", quails exposed to drinking water, without ABA, "EC1x" and "EC1000x" (0.31 mg a.i./L and 310.0 a.i./L, respectively; via commercial formulation Kraft® 36EC). The open field test showed anxiolytic response in birds exposed to ABA. These birds did not show locomotor changes or aggressive behavior in the aggressiveness test. Quails exposed to the pesticide did not react to the introduction of an object in the experimental box during the object recognition test, and it suggested perception deficit due to ABA. Moreover, these birds did not recognize the cat (Felix catus) and the vocalization of a hawk (Rupornis magnirostris) as potential predatory threats. These responses also suggest anti-predatory behavior deficit due to the pesticide. Thus, our study is pioneer in showing that water with ABA, at tested concentrations, influences the behavior of C. coturnix japonica, as well as in highlighting the potential impacts of this pesticide on this group of birds.


Assuntos
Comportamento Animal/efeitos dos fármacos , Coturnix/fisiologia , Ivermectina/análogos & derivados , Praguicidas/toxicidade , Animais , Gatos , Feminino , Ivermectina/toxicidade
20.
Environ Sci Pollut Res Int ; 25(15): 15235-15244, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29679270

RESUMO

The aim of the current study is to assess possible erythrocyte mutagenic effects on Lithobates catesbeianus tadpoles exposed to water contaminated with 2,4-D. In order to do so, tadpoles were exposed to a predictive and environmentally relevant herbicide concentration (1.97 mg/L), which is likely to be found in lentic environments formed by superficial water runoffs in pasture areas where the herbicide was applied. The micronucleus test, as well as tests for other nuclear abnormalities, was conducted after 3, 5, and 9 days of exposure (d.e.). Changes in the biomass and mouth-cloaca length or interference in the larval development of the animals (in the three evaluated times) were not recorded. However, tadpoles exposed to 2,4-D showed the highest total number of nuclear abnormalities, as well as the highest frequency of binucleated erythrocytes and kidney-shaped nuclei (shortly after 3 d.e.). The micronucleus frequency was also higher in animals exposed to 2,4-D (in the 3rd, 5th, and 9th d.e.), as well as the frequency of binucleated cells (3rd, 5th, and 9th d.e.) presenting notched (9th d.e.) and blebbled (9th d.e.) nuclei in comparison to those of the control, after 5 and 9 days of exposure. Therefore, the current study is a pioneer in showing that 2,4-D has a mutagenic effect on L. catesbeianus tadpoles, even at low concentrations (environmentally relevant) and for a short period of time, a fact that may lead to direct losses in anuran populations living in areas adjacent to those subjected to 2,4-D herbicide application.

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