Changes in sperm motility of amazonian fish Tambaqui Colossoma macropomum (Cuvier 1816) (Characiformes: Serrasalmidae) exposed to two pesticides / Alterações na motilidade espermática do peixe amazônico Tambaqui Colossoma macropomum (Cuvier 1816) (Characiformes: Serrasalmidae) exposto a dois pesticidas

Abstract The great biodiversity of neotropical fish species that have external fertilization as a reproductive strategy, like the tambaqui, requires more careful analyzes in toxicological tests of the various pesticides implemented in Brazilian agriculture over the last few years. In this context, the objective of the present work was to evaluate possible sperm alterations in tambaqui (Colossoma macropomum) semen exposed to two different pesticide residues. Seminal samples of sexually mature tambaqui males from a local fish farm were used. Semen was collected eight hours after hormone induction into graduated glass tubes. After initial assessment of the lack of prior activation, the experiment was carried out in a factorial scheme, testing two pesticides widely used in agricultural systems (glyphosate and fenitrothion). For each pesticide, five concentrations were tested (6, 12, 24, 120 and 240 mg/L), with motility analysis at times 0, 30 and 60 seconds after activation. As a control, activation with 0.9% NaCl solution and motility analysis at the same times described for pesticides were used. Results indicate that in natura samples exhibited initial motility of 89.2 ± 4.9% and mean duration of 100 seconds (up to 10% sperm motility). The reduction in sperm motility occurred significantly (p < 0.05) after 30 seconds in all concentrations tested, except for the concentration of 240 mg/L because no activation was observed. The tests described here demonstrate that tambaqui semen was sensitive to the process of exposure to pesticide residues, and can be used in biomonitoring analyzes of the aforementioned agricultural pesticides.

Resumo A grande biodiversidade das espécies de peixes neotropicais que possuem a fertilização externa como estratégia reprodutiva, a exemplo do tambaqui, exige análises mais criteriosas em testes toxicológicos dos diversos defensivos agrícolas implementados na agricultura brasileira ao longo dos últimos anos. Nesse contexto, o objetivo do presente trabalho foi avaliar possíveis alterações espermáticas no sêmen de tambaqui (Colossoma macropomum) exposto a resíduos de dois diferentes pesticidas. Foram utilizadas amostras seminais de machos de tambaqui sexualmente maduros provenientes de uma piscicultura local. O sêmen foi coletado oito horas pós indução hormonal em tubos de vidro graduados. Após avaliação inicial de inexistência de ativação prévia, foi realizado o experimento em esquema fatorial, sendo testados dois pesticidas muito utilizados em sistemas agrícolas (glifosato e fenitrotiona). Para cada pesticida foram testadas cinco concentrações (6, 12, 24, 120 e 240 mg/L), com análise da motilidade nos tempos 0, 30 e 60 segundos pós ativação. Como controle, foi utilizada a ativação com solução de NaCl a 0,9% e análise da motilidade nos mesmos tempos descritos para os pesticidas. Resultados indicam que as amostras in natura exibiram motilidade inicial de 89,2 ± 4,9% e tempo de duração médio de 100 segundos (até 10% de motilidade espermática). A redução da motilidade espermática ocorreu de forma significativa (p < 0,05) após 30 segundos em todas as concentrações testadas, exceto na concentração de 240 mg/L por não ter sido observada ativação. Os testes aqui descritos demonstram que o sêmen de tambaqui se mostrou sensível ao processo de exposição aos resíduos de pesticidas, podendo ser utilizado em análises de biomonitoramento dos referidos defensivos agrícolas.

Exposure to the herbicide atrazine induces oxidative imbalance, morphological damage and decreased survival in juvenile fish

Synthetic herbicides have been intensively used in weed control, although often involved in environmental contamination, critically affecting non-target species. However, never was investigated the effect of commercial formulation using atrazine on developing juvenile fish exposed for 35 days. Juveniles (Astyanax altiparanae) (n = 600) were assigned to the following ATZ-exposed groups: 0 (CTR-control), 0.56 (ATZ0.56), 1.00 (ATZ1.00), 1.66 (ATZ1.66) and 11.66 (ATZ11.66) µg/L. We found a 36.6% decrease in juvenile survival rate in the ATZ11.66 group compared to control and other groups. Juveniles from ATZ11.66 also showed hyperglycemia and increased cortisol levels. Increased the imbalance oxidative with an increase in malondialdehyde (MDA) and Carbonylated proteins levels markers in muscle, gills, and liver. We also found increased activity of the antioxidant enzymes superoxide dismutase (SOD) in gills and SOD and catalase (CAT) in muscles from ATZ11.66 fish, and increased glutathione S-transferase (GST) activities in the liver from all exposed groups compared to control. The morphological consequences of this were loss of secondary lamella integrity, increased mucus-secreting cells, hyperplasia, and lamellar fusion, as well as increased aneurysms percentage. The liver showed vascular congestion associated with endothelial hyperplasia, steatosis, and a decrease in the nuclei percentage. Our results showed that exposure to a commercial formulation of ATZ at 11.66 µg/L can be causing an imbalance in the oxidative markers and morphological damages and decreased survival in a juvenile Neotropical species of great ecological relevance and commercial interest.

Validagao da espécie Dendrocephalus brasiliensis como organismo teste de água doce em estudos ecotoxicológicos para avaliagao de fármacos utilizados no tratamento da COVID-19 / Validation of the species Dendrocephalus brasiliensis as a freshwater test organism in ecotoxicological studies for evaluation of pharmaceuticals used in the treatment of COVID-19

Resumo Os contaminantes emergentes (CE), sao substáncias químicas (fármacos, produtos de higiene pessoal, drogas ilícitas entre outros) que estao presentes no ambiente como consequéncia da atividade antrópica e a falta de adequagao dos processos convencionais de tratamento de água e esgoto que nao logram remové-los eficientemente. Na atualidade o uso disseminado e desmedido de fármacos no tratamento da pandemia de COVID 19 tem aumentado a preocupagao dos impactos decorrentes da contaminagao por fármacos em ambientes aquáticos, consequéncia da liberagao no ambiente de grandes quantidades destes compostos. Assim, estudos de ecotoxicidade aquática sao fundamentais para avaliar o efeito de substáncias químicas tóxicas nas análises de impactos ambientais, sobretudo quando utilizado organismos representativos da biota aquática local, garantindo assim, maior confiabilidade e representatividade dos resultados obtidos. Diante disto, o objetivo deste trabalho foi validar a utili-dade do Dendrocephalus brasiliensis (Branchoneta) espécie autóctone do nordeste brasileiro como organismo teste para estudos de ecotoxicidade de fármacos utilizados no tratamento da COVID 19. Testes ecotoxicológicos utilizando D. brasiliensis foram realizados utilizando solugóes dos fármacos paracetamol, hidroxicloroquina, ivermectina e ibuprofeno, em concentragóes de 0,0025 até 600,0 mg/L seguindo os protocolos descritos pela Associagao Brasileira para Normas Técnicas (ABNT) para toxicidade aguda, protocolo padronizado para a realizagao do ensaio ecotoxicológicos utilizando como organismo teste a Daphnia magna, o qual foi empregada como referencia para comparar o padrao de resposta. Com os resultados obtidos foi realizado o cálculo da CL50-48h considerando como desfecho a morte dos organismos, ivermectina (< 0,0025 - < 0,0025), hidroxicloroquina (3,70 - 14,09), ibuprofeno (12,25 - 107,52), paracetamol (8,53 - 9,61), resultados CL50-48h mg/l D. magna e D. brasiliensis respectivamente. Os resultados obtidos mostraram um padrao diferenciado dependente da espécie e do fármaco analisado observando-se uma menor sensibilidade frente a exposigao da D. brasiliensis em comparagao a D. magna demonstrando a valia da D. brasiliensis como organismo teste. Pesquisas futuras dirigidas a analisar as potenciais interagóes destes fármacos em concentragóes ambientais reais sao necessárias para completar a validagao e ter uma aproximagao dos eventos acometidos em ambientes impactados por estes fármacos.

Abstract Emerging contaminants (EC) are chemical substances (pharmaceuticals, personal hygiene products, illicit drugs, among others) that are present in the environment because of human activity and the lack of adequacy of conventional water and sewage treatment processes that do not manage to remove them efficiently. Currently, the widespread and excessive use of drugs in the treatment of the COVID 19 pandemic has increased concern about the impacts resulting from contamination by drugs in aquatic environments, because of the release into the environment of large amounts of these compounds. Thus, aquatic ecotoxicity studies are essential to evaluate the effect of toxic chemical substances in the analysis of environmental impacts, especially when using representative organisms of the local aquatic biota, thus ensuring greater reliability and representativeness of the results obtained. In view of this, the objective of this work was to validate the usefulness of Dendrocephalus brasiliensis (Branchoneta), an autoch-thonous species from northeastern Brazil as a test organism for ecotoxicity studies of drugs used in the treatment of COVID 19. Ecotoxicological tests using D. brasiliensis were performed using drug solutions paracetamol, hydroxychloroquine, ivermectin and ibuprofen, in concentrations from 0.0025 to 600.0 mg/L following the protocols described by the Brazilian Association for Technical Norms (ABNT) for acute toxicity, standardized protocol for carrying out the ecotoxicological assay using as a test organism Daphnia magna, which was used as a reference to compare the response pattern. Based on the results obtained, the LC50-48h was calculated considering the death of organisms, ivermectin (< 0.0025 - < 0.0025), hydroxychloroquine (3.70 - 14.09), ibuprofen (12.25 - 107.52), paracetamol (8.53 - 9.61), results LC50-48h mg/l D. magna and D. brasiliensis respectively. The results obtained showed a differenti-ated pattern depending on the species and the analyzed drug, observing a lower sensitivity to exposure of D. brasiliensis compared to D. magna, demonstrating the value of D. brasiliensis as a test organism. Future research aimed at analyzing the potential interac-tions of these drugs at real environmental concentrations is necessary to complete the validation and to have an approximation of the events affected in environments impacted by these drugs.

Ensaios de toxicidade para avaliagao de águas superficiais estuarinas usando Nitocra sp. como organismo-teste alternativo / Toxicity tests for the evaluation of estuarine surface waters using Nitocra sp. as an alternative test organism

Resumo A crescente poluigao de ambientes marinhos e estuarinos por descarga de efluentes é um problema mundial. Os ensaios ecotoxicológicos vem sendo amplamente utilizados para monitorar os efeitos deste tipo de poluigao e, atualmente sao incorporados na legislagao ambiental de diversos países, nomeadamente no Brasil. Contudo, sao poucos os estudos realizados em áreas costeiras e a padronizagao de métodos com organismos nativos, representativos de ecossistemas locais, é insuficiente. Nitocra sp. tem sido eficientemente utilizado em ensaios ecotoxicológicos com sedimentos e águas intersticiais, sendo neces-sário avaliar a sua adequagao na análise de águas superficiais estuarinas. Amostras pontuais de agua do baixo estuário Jundiaí -Potengi (EJP) foram coletadas mensalmente durante 18 meses, em áreas com (CE) e sem (SE) recegao de efluentes tratados. Nitocra sp. e Mysidopsis juniae (espécie padronizada) foram os organismos teste utilizados nos ensaios ecotoxicológicos. Efeitos letais (taxa de mortalidade) e subletais (taxa de reprodugao) foram analisados considerando a caracterizagao microbiológica e físico-química das amostras testadas. Os teores de oxigenio dissolvido, salinidade, demanda bioquímica de oxigenio, nitrogenio amoniacal e amoniacal total, nitrogenio total, óleos e graxas, sólidos suspensos e sedimentáveis, potássio total e coliformes termotolerantes determinados nas amostras CE e SE, traduzem diferentes níveis de poluigao nos locais amostrados. As cartas-controle de Nitocra sp. e M. juniae indicaram boa reprodutibilidade laboratorial, e apesar dos organismos teste terem exibido diferentes perfis ecotoxicológicos, o aumento da taxa de mortalidade de ambos esteve associada a emissao de esgoto tratado. O uso de diferentes organismos teste favorece a representatividade dos ensaios ecotoxicológicos. Considerando o perfil de Nitocra sp. no monitoramento do EJP, o seu estabelecimento como organismo-teste padronizado necessita de mais estudos, incluindo a utilizagao de nauplii em bioensaios.

Abstract Increasing pollution of marine and estuarine environments from wastewater discharge is a worldwide problem. Eco-toxicological tests are widely used to monitor the effects of this type of pollution and are currently being incorporated into the environmental legislation of several countries, including Brazil. However, few studies have been conducted in coastal areas, and standardization of methods with native organisms representative of local ecosystems is insufficient. Nitocra sp. has been efficiently used in ecotoxicological tests with sediments and interstitial waters, and its suitability for estuarine surface water analysis needs to be assessed. Point samples from the lower Jundiaí-Potengi estuary (JPE) in areas with (CE) and without (SE) discharge of treated effluents were collected monthly for 18 months. Nitocra sp. and Mysidopsis juniae (standardized species) were the test organisms used in the ecotoxicological assays. The lethal (mortality rate) and sublethal (reproduction rate) effects were analyzed considering the microbiological and physicochemical characterization of the tested samples. Dissolved oxygen, salinity, biochemical oxygen demand, ammoniacal and total ammoniacal nitrogen, total nitrogen, oils and greases, suspended and settleable solids, total potas-sium and thermotolerant coliform bacteria determined in samples from CE and SE, reflect varying levels of pollution at the sampled sites. The control charts of Nitoera sp. and M. juniae indicated good reproducibility in the laboratory, and although the test organisms had different ecotoxicological profiles, the mortality rate of both organisms was related to the discharge of treated wastewater. The use of different test organisms increases the representativeness of the ecotoxicological tests. Given the profile of Nitoera sp. in JPE monitoring, further studies, including the use of nauplii in bioassays, are needed to establish it as standardized test organism.

Environmental parameters modulate lead chloride toxicity on Artemia salina

Different environmental conditions can influence the effects of toxic agents on living beings. Recently, a series of experiments performed in Artemia salina submitted to different kinds of intoxication have shown that both, isotherapic and succussed watercan change Artemia salina ́s bio resilience at different levels. Moreover, it seems to vary according to the circalunar cycle. Objective:To verify if circalunar phases and water agitation can modify the toxicity of lead chloride on Artemia salina in vitro. Methodology:Artemia salina cysts were exposed to seawater containing 0.04% of lead chloride (equal to EC10 or 10% effective concentration, previously determined in a pilot study) in 96-well culture plates. Thirty-six experimental repetitions were performed in four series to observe the possible effects of adding stirred water, the so-called succussed water, and the moon phases. The hatched cysts were recorded after 48 hours using a digital microscope (1000x magnification) to identify the hatching percentage and the viability and mobility of the born nauplii. Results:The exposition of cysts to PbCl2 led to an increase in the hatching rate, and it was more evident during the full moon (p = 0.00014) The addition of succussed water into the seawater medium reduced this effect to the baseline levels. An increase in mobility was seen in nauplii born from exposed cysts during the full moon (p = 0.00077), but this effect was not affected by the treatment with succussed water. Discussion:Although the effects of lead chloride EC10 on the increase of nauplii hatching were expected, two environmental variables changed the sensitivity of cysts to this harmful stimulus. The circalunar cycle varied the hatching rate according to the moon phase, even in laboratory conditions, and the addition of succussed water into the medium reduced the hatching rate, even with different intensities according to the moon phase. The organization of nano and microbubbles generated after the succussion of water could be related to this protective effect and can explain, at least partially the effects of high diluted preparations on this biological context. Conclusion:Environmental factors, such as the circalunar cycle and products of water agitation, can modulate the adaptative control of hatching in Artemia salina exposed to lead chloride at EC10.

Mercury chloride toxicity attenuation of the Brine Shrimp Artemia Salinaafter treatment with Mercurius corrosivusas isotherapic

Isotherapics preparedfromtoxic substances have been described as attenuation factors for heavy metal intoxicationin aquatic animals. Herein, Artemia salinaand mercury chloride were usedas a model to identify treatment-related bioresilience. The aim was to describe the effects of Mercurius corrosivus(MC) in different potencies on Artemia salinacyst hatching and on mercury bioavailability. Artemia salinacysts were exposed to 5.0 µg/mL of mercury chloride during the hatching phase. MC6cH, 30cH, and 200cHwere prepared and poured into artificial seawater. Different controls were used (nonchallenged cysts and challenged cysts treated with water, succussed water, and Ethilicum 1cH). Four series of nine experiments were performed for4 weeks to evaluate the percentage of cyst hatchingconsidering all moon phases. Soluble total mercury (THg) levels and precipitated mercury content were also evaluated. Solvatochromic dyes were used to check for eventual physicochemical markers of MCbiological activity. Two-way analysis of variance (ANOVA) with mixed modelswas used for evaluating the effect of different treatments andthe simultaneous influence of the moon phases on the cystshatching rate, at both observation times (24 and 48 hours).When necessary, outliers were removed, using the Tukeycriterion.Thelevel of significance αwas set at 5%. Significant delay (p<0.0001) in cyst hatching was observed after treatment with MC30cH, compared with the controls. An increase inTHg concentration in seawater (p<0.0018) and of chlorine/oxygen ratio (p<0.0001) in suspended micro-aggregateswas also seen, with possiblerelation with mercury bioavailability. Specific interaction of MC30cH with the solvatochromic dye ET33 (p<0.0017) was found. The other observed potencies of Mercurius corrosivus6 and 200 cH were not significant in relation to the observed groups.The results werepostulated as being protective effects of MC30cH on Artemia salina, by improving its bioresilience.

Aftershocks of the Samarco disaster: diminished growth and increased metal content of Raphanus sativuscultivated in soil with mining tailings

The collapse of the Fundão tailings dam of the Samarco mining complex in Mariana, Brazil, was the largest mining disaster in the world to date with many socio-economic and environmental impacts. Soil affected by mining tailings was severely altered with negative impacts for agriculture. We tested whether diluting mining tailings with organic soil would eliminate or at least attenuate the ecotoxic effects on plant development and performance. We cultivated radish, Raphanus sativus,in substrates containing different proportions of mining tailings and organic soil: pure tailings (T100%); 2) tailings75%+ soil25%(T75%); 3) tailings50%+ soil50%(T50%); 4) tailings25%+ soil75%(T25%), and 5) pure organic soil (Soil100%, control). There were large differences in soil quality parameters between the 100% tailings treatment (T100%) and the control (Soil100%), as well as for some parameters in the most diluted treatment -T25%(Ca2+, Fe, Mn) in relation to the controltreatment. Although dilution of the tailings soil improved radish development, there was lower radish productivity (leaf area, total biomass, and root/tuber biomass) than for pure soil (control). There were also significantly higher amounts of bioaccumulated metals in radish tubers grown with tailings, even when grown in T25%for Fe content and in T75%for Mn content. These results present a worrisome scenario for human communities in the region of the Doce river, as human consumption of crops produced in soil contaminated with tailingsis not recommended due to potential toxicological effects from high metal concentrations.(AU)

Effects of sheep manure in agricultural soils on the behavior of Folsomia candida and initial growth and development of Avena sativa / Efeitos do esterco de ovelha em solos agrícolas no comportamento de Folsomia candida e no crescimento e desenvolvimento inicial de Avena sativa

Abstract The aim of this study was to evaluate the effects of sheep manure in agricultural soils on the behavior of Folsomia candida and initial growth and development of Avena sativa. For this, an Oxisol was submitted to different doses of sheep manure and was subsequently evaluated for Folsomia candida survival and avoidance behavior through standardized ecotoxicological assays, the initial performance of oats by germination test and the soil basal respiration rate by respirometry methodology. There was an increase in the basal respiration rate of the soil by the application of sheep manure and this was consistent with the increase of the doses. The survival rate and avoidance behavior of springtails were not altered and there was no change in the initial performance of oats, indicating that this manure can be used for organic fertilization of soils with low soil pollutant potential.

Resumo O objetivo deste estudo foi avaliar os efeitos do esterco de ovelha em solos agrícolas no comportamento de Folsomia candida e no crescimento e desenvolvimento inicial de Avena sativa. Para isso, um Latossolo foi submetido a diferentes doses de esterco de ovelha e posteriormente avaliado quanto ao comportamento de fuga e a sobrevivência de Folsomia candida por meio de ensaios ecotoxicológicos padronizados, desempenho inicial da aveia pelo teste de germinação e taxa respiratória basal do solo pela metodologia da respirometria. Houve um aumento na taxa de respiração basal do solo pela aplicação de esterco de ovelha e isso foi consistente com o aumento das doses. A taxa de sobrevivência e o comportamento de fuga dos colêmbolos não foram alterados e não houve alteração no desempenho inicial da aveia, indicando que esse esterco pode ser usado para fertilização orgânica de solos com baixo potencial poluente no solo.

TOXICIDAD AGUDA DEL HERBICIDA PARAQUAT EN Oreochromis niloticus (CICHLIDAE) Y Macrobrachium olfersii (PALAEMONIDAE) / Paraquat's herbicide acute toxicity in Oreochromis niloticus (Cichlidae) and Macrobrachium olfersii (Palaemonidae)

RESUMEN El Paraquat es un herbicida utilizado en la actividad agropecuaria para controlar hierbas, su modo de acción es por medio de contacto y no selectivo. Debido a su alta solubilidad en agua y baja volatilidad representa un riesgo potencial para organismos acuáticos, principalmente los que son cultivados con aguas superficiales que reciben impacto de la actividad agrícola. La tilapia Oreochromis niloticus y el langostino Macrobrachium olfersii son organismos de importancia comercial para la industria acuícola del estado de Veracruz, México. El objetivo de este estudio fue determinar la Concentración Letal Media (CL50) del herbicida Dasurquat® (ingrediente activo Paraquat) a través de un bioensayo de toxicidad aguda (96 horas). Se utilizaron como especímenes de prueba a juveniles de tilapia O. niloticus (peso promedio = 10 mg, longitud total= 8,75 mm) y otro el ensayo fue con poslarvas de langostino M. olfersii (peso promedio = 5 mg, longitud total= 5,72 mm). Se emplearon cinco concentraciones (5, 10, 20, 40 y 80 μL-1 para el bioensayo con juveniles de tilapia; para el bioensayo con poslarvas de langostino las concentraciones fueron 0,1, 0,2, 0,5, 0,7 y 1 μL-1). El diseño experimental consideró un control negativo, con dos repeticiones y dos réplicas por cada tratamiento. El análisis de datos se realizó con el método Probit para determinar la CL50 a 96 horas, se obtuvo un valor para juveniles de O. niloticus de 17,49 μL-1 con intervalo de confianza (95 %) con límite inferior de 13,75 μL-1 y límite superior 22,25 μL-1, para las larvas de M. olfersii se obtuvo un valor de 0,31 μL-1 con intervalo de confianza (95 %) con límite inferior de 0,26 μL-1 y límite superior 0,35 μL-1. El análisis de varianza demostró que no existió diferencia estadística significativa (p > 0.05) entre las réplicas de los tratamientos. Se concluye que es necesario continuar con estudios para evaluar su toxicidad en organismos acuáticos debido al amplio uso de este herbicida en la actividad agropecuaria, y determinar su riesgo para otras actividades productivas además de la acuicola.

ABSTRACT Paraquat is an herbicide used in the agricultural industry for weed and undergrowth control, its mode of action is by contact and nonselective. Due to its high-water solubility and low volatility, it represents a potential risk for non-target organisms. Oreochromis niloticus tilapia and the prawn Macrobrachium olfersii are important commercial species for Veracruz's aquaculture industry. The objective of this study was to determine the Mean Lethal Concentration (LC50) of the herbicide Dasurquat® (active ingredient Paraquat) through an acute toxicity bioassay (96 hours). Juvenile O. niloticus (average weight = 10 mg, total length = 8.75 mm) and juvenile M. olfersii postlarvae (average weight = 5 mg, total length = 5.72mm) were used as test specimens. Five herbicide concentrations (5, 10, 20, 40 and 80 μL-1 for tilapia and 0.1, 0.2, 0.5, 0.7 y 1 μL-1 for prawn) were applied. The experimental design considered a negative control, with two replications and two replicates for each treatment. Probit analysis determined that the LC50 at 96 hours for O. niloticus was 17.49 μL-1, with a lower 95 % confidence limit of 13.75 μL-1 and an upper limit of 22.25 μL-1, whereas for M. olfersii the LC50 at 96 hours was 0.31 μL-1, with a lower 95 % confidence limit of 0.26 μL-1 and an upper limit of 0.35 μL-1. The analysis of variance showed that there was no significant statistical difference (p > 0.05) between the replicates of the treatments. It is concluded that it is necessary to continue evaluating its toxicity in aquatic organisms due to the wide use of this herbicide in Veracruz's agricultural activity, to determine its potential risk to other activities.

Toxicity of three organophosphate insecticides in anuran embryos at different temperatures / Toxicidad de tres insecticidas organofosforados en embriones de anuros a diferentes temperaturas

RESUMEN Los efectos de diferentes agroquímicos y de la temperatura han sido temas recurrentes en la investigación en anuros; sin embargo, estas variables se han abordado de manera independiente sin considerar que pueden ejercer una presión simultánea sobre las especies. Por esta razón, este trabajo tiene como objetivo determinar la toxicidad (a través de la Concentración Letal Media -CL50) de los insecticidas organofosforados clorpirifos, diazinón y monocrotofos, bajo tres regímenes térmicos (23, 28 y 33 ± 1 °C) sobre embriones de tres especies de anuros. De acuerdo a los valores de CL50, el insecticida clorpirifos fue el más tóxico, seguido del diazinón y del monocrotofos. Por su parte, de manera general se encontró un incremento de la toxicidad de los insecticidas organofosforados a la temperatura más alta de experimentación (33 °C). Además, el efecto de la temperatura se hizo más notorio para los organismos expuestos al clorpirifos, el insecticida más letal. Estos resultados sugieren un efecto negativo para la fauna acuática de anuros debido al actual uso desmesurado de este tipo de agroquímicos y a su interacción con la temperatura ambiental.

ABSTRACT In anurans, the effects of different agrochemicals and temperature have been recurrent topics in research; however, these variables are addressed independently without considering that they can exert a simultaneous pressure on the species. For this reason, this work aims to determine the toxicity (through the Medium Lethal Concentration -LC50) of the organophosphate insecticides: chlorpyrifos, diazinon and monocrotophos, under three thermal regimes (23, 28 and 33 ± 1 °C) on embryos ofthree species of anurans. According to the LC50 values, the chlorpyrifos insecticide was the most toxic, followed by diazinon and monocrotophos. On the other hand, an increase in the toxicity of the organophosphate insecticides studied was generally found at the highest experimental temperature (33 °C). In addition, the effect of temperature became more noticeable for the organisms exposed to chlorpyrifos, the most lethal insecticide. These results suggest a negative effect for the aquatic fauna of anurans due to the current excessive use of this type of agrochemicals and their interaction with environmental temperature.

How do pesticides affect bats? - A brief review of recent publications / Como os pesticidas afetam os morcegos? - Uma breve revisão de publicações recentes

Increased agricultural production has been increased use of pesticides worldwide, which poses a threat to both human and environmental health. Recent studies suggest that several non-target organisms, from bees to mammals, show a wide variety of toxic effects of pesticides exposure, including impaired behavior, development and reproduction. Among mammals, bats are usually a neglected taxon among ecotoxicological studies, although they play important ecological and economical roles in forest ecosystems and agriculture through to seed dispersal and insect population control. Considering their wide variety of food habits, bats are exposed to environmental pollutants through food or water contamination, or through direct skin contact in their roosting areas. In order to better understand the risk posed by pesticides to bats populations, we compiled studies that investigated the main toxicological effects of pesticides in bats, aiming at contributing to discussion about the environmental risks associated with the use of pesticides.

O aumento da produção agrícola tem levado ao aumento do uso de pesticidas em todo o mundo, o que representa uma ameaça para a saúde humana e ambiental. Estudos recentes sugerem que vários organismos não-alvo, de abelhas a mamíferos, apresentam uma grande variedade de efeitos tóxicos após a exposição aos pesticidas a pesticidas, incluindo alterações de comportamento, no desenvolvimento e na reprodução. Entre os mamíferos, os morcegos geralmente são negligenciados entre os estudos ecotoxicológicos, embora desempenhem importantes papéis ecológicos e econômicos nos ecossistemas florestais e na agricultura por meio do controle de dispersão de sementes e de populações de insetos. Considerando sua ampla variedade de hábitos alimentares, eles estão expostos a poluentes ambientais através da contaminação de alimentos ou água, ou através do contato direto com a pele em suas áreas de descanso. Para entender melhor o risco que os agrotóxicos representam para as populações de morcegos, compilamos estudos que investigaram os principais efeitos toxicológicos de agrotóxicos em morcegos, visando à discussão sobre os riscos ambientais associados ao uso de agrotóxicos.

Medicamentos sobrantes y caducados en el hogar ¿su almacenaje y desecho representan un problema de salud pública? / Leftover and expired medicines in households: Is their storage and disposal a public health problem?

RESUMEN Los medicamentos sobrantes y caducados en el hogar deberían ser eliminados de una manera que garantice la seguridad de la población, y que tenga un impacto negativo mínimo en el medio ambiente. Desde esta perspectiva se desarrolló el presente estudio cuyo objetivo fue conocer las prácticas de desecho de medicamentos del botiquín familiar en estudiantes de medicina en Quito-Ecuador. Entre diciembre de 2018 y enero de 2019, se encuestaron 498 estudiantes de diferentes semestres, y se evidenció que hasta un 30,3% de estudiantes alguna vez desechó los medicamentos a través del inodoro, y un 7,2% reconoció que sacaba los medicamentos del empaque primario, para depositarlos en la basura común. Como objetivo secundario se analizaron los medicamentos caducados y sobrantes del botiquín familiar de los encuestados. Se encontró que los medicamentos más frecuentes fueron metformina, seguido por acetaminofén, espironolactona e ibuprofeno. El estudio muestra la necesidad de desarrollar estrategias multisectoriales para la implementación de políticas sobre el desecho doméstico, las cuales permitirán controlar, y en el mejor de los casos, disminuir el impacto negativo tanto ambiental como en salud pública.

ABSTRACT: Leftover and expired medicines in households must be disposed of in such a way as to ensure the population's safety, while generating the lowest possible negative impact on the environment. In this context, the aim of this study was to explore drug disposal practices related to home medicine cabinets among medical students in Quito, Ecuador. Between December 2018 and January 2019, 498 students from different semesters were surveyed. Data show that up to 30.3% of students had flushed their medicines down the toilet at least once, while 7.2% acknowledged that they had removed the medicines from their packaging to deposit them in a household garbage disposal. A secondary aim of the study was to analyze expired and leftover drugs in participants' medicine cabinets. Metformin was the most common medication found, followed by acetaminophen, spironolactone, and ibuprofen. This study shows the urgent need to develop multisectoral strategies for the implementation of policies on pharmaceutical domestic waste, which will make it possible to control and reduce the negative impact on both the environment and public health.

Evidence of mutagenic and lethal effects of herbicides on Amazonian frogs / Evidências de efeitos mutagênicos e letais de herbicidas em sapos da Amazônia

Amphibians are excellent bioindicators because they are sensitive to chemical pollution and can indicate ecosystem changes due to the presence of or exposure to chemical compounds. Here we report evidence of the impact of herbicides, including glyphosate, on amphibians in a locality in the central Brazilian Amazon and compare it with data from other biomes in Brazil. We observed malformations in three species of Leptodactylus and local extinctions of Scinax ruber and Rhinella marina from reproductive sites close to an area where herbicides had been applied. The observations in the Amazon are similar to reports from Brazils Atlantic forest on morphological anomalies and mortality in amphibians exposed to herbicides. We warn of the threat of expanding crops for the production of biofuels in the Amazon due to their cultivation being associated with agrochemicals, including glyphosate, posing a threat to the biodiversity of the Amazon biome.

Os anfíbios são ótimos bioindicadores porque são sensíveis à poluição química, indicando alterações ecossistêmicas pela presença de ou pela exposição a compostos químicos. Aqui nós relatamos evidências do impacto de herbicidas, incluindo glifosato, em anfíbios em uma localidade na Amazônia central brasileira e as comparamos com dados de outros biomas no Brasil. Nós observamos malformações em três espécies de Leptodactylus e extinção local de Scinax ruber e Rhinella marina em sítios reprodutivos próximos a uma área onde herbicidas haviam sido aplicados. Os resultados observados na Amazônia são semelhantes aos observados na Mata Atlântica do Brasil, com alterações morfológicas e mortalidade em anfíbios expostos a herbicidas. Alertamos para a ameaça de expansão de culturas para a produção de biocombustíveis na Amazônia, devido ao fato de o cultivo estar associado a agroquímicos, incluindo o glifosato, representando uma ameaça à biodiversidade do bioma Amazônia.

Different diets with and without inclusion of antimicrobial additives alter the toxicity of swine manure to springtails and earthworms? / Diferentes dietas com e sem inclusão de aditivos antimicrobianos alteram a toxicidade do esterco de suíno para colêmbolos e minhocas?

The objective of this study was to measure the impact on part of soil fauna of application of non-stabilized (fresh) manure from post-weaning pigs fed diets, formulated with or without the use of dual-purpose wheat (15% inclusion), and with or without the use of antimicrobial growth-promoting additives (100 mg kg-1 doxycycline + 50 mg kg-1 colistin + 250 mg kg-1 Zn oxide). Two species of edaphic organisms were evaluated, the springtails Folsomia candida and the earthworms Eisenia andrei, using ecotoxicological avoidance behavior tests. The treatments were swine manure from: RR: Reference Ration; WR: Wheat Reference; RA: Reference Ration + Antimicrobial Additives; WA: Wheat Reference + Antimicrobial Additives. The doses of waste used for treatments were as follows: 0 (control), 5, 10, 20, 30, 40, 65 and 100 m³ ha-1 for the springtails, and 0 (control), 5, 10, 20, 30, 40 and 65 m³ ha-1 for the earthworms, applied in the Oxisol. The experimental design was completely randomized with four replicates. The use of non-stabilized swine manure did not affect the avoidance behavior of F. candida at any dose, regardless of the use of antimicrobial additives or wheat. For E. andrei, there was avoidance behavior at all treatments and doses used. These avoidance behaviors were related to the sensitivity of each species of soil organism. The avoidance behavior for earthworms was related to the doses of non-stabilized swine manure in soil and not to the various diets and/or the use of growth-promoting additives

O estudo foi realizado com objetivo de mensurar o impacto sobre parte da fauna do solo de aplicações de dejetos sem estabilização (frescos), provenientes de suínos na fase de creche arraçoados com diferentes dietas, formuladas com ou sem o uso do trigo de duplo propósito (15% de inclusão), e com ou sem o uso de aditivos antimicrobianos promotores de crescimento (100 mg kg-1 de doxiciclina + 50 mg kg-1de colistina + 250 mg kg-1 de óxido de Zn). Foram avaliadas duas espécies de organismos edáficos, colêmbolos Folsomia candida e minhocas Eisenia andrei, com o uso de ensaios ecotoxicológicos de comportamento de fuga. Os tratamentos foram dejetos de suínos provenientes de: RR: Ração Referência; WR: Trigo Referência; RA: Ração Referência + Aditivos Antimicrobianos; WA: Trigo Referência + Aditivos Antimicrobianos. As doses de dejetos utilizadas para os tratamentos foram: 0 (controle), 5, 10, 20, 30, 40, 65 e 100 m³ ha-1 para os colêmbolos, e 0 (controle), 5, 10, 20, 30, 40 e 65 m³ ha-1 para as minhocas, aplicadas em Latossolo Vermelho distrófico. O delineamento experimental foi inteiramente casualizado com quatro réplicas. A utilização de dejetos de suínos não estabilizados não afetou a fuga de F. candida em nenhuma das doses, independente do uso ou não de aditivos antimicrobianos ou de trigo. Já para E. andrei o comportamento foi inverso e houve fuga em todos os tratamentos e doses utilizados. Os comportamentos de fuga foram relacionados à sensibilidade de cada espécie de organismo edáfico. O comportamento de fuga para minhocas foi relacionado com as doses dos dejetos de suínos não estabilizados no solo e não às várias dietas e/ou ao uso dos aditivos promotores de crescimento

Efeitos tóxicos dos sedimentos do estuário do rio Capibaribe em embriões de zebrafish (Danio rerio) / Toxic effects of sediments of the Capibaribe estuary on zebrafish embryos (Danio rerio)

O presente estudo utilizou embriões de Danio rerio expostos aos elutriatos dos sedimentos estuarinos do rio Capibaribe, dos períodos chuvoso e seco, e analisou os efeitos letais, teratogênicos, bem como a frequência cardíaca. Os testes de toxicidade com os embriões seguiram as diretrizes da OECD 236. Mediante os resultados obtidos, a frequência cardíaca e a teratogenicidade foram os efeitos mais observados nos animais quando submetidos às amostras. Entre os efeitos teratogênicos, o retardo geral no desenvolvimento dos embriões foi o mais frequente durante as análises. Tais efeitos tóxicos se modificaram entre os pontos e entre os períodos de coleta. Essa variação de toxicidade pode estar relacionada à diversidade de atividades realizadas no entorno desse estuário, a influência do regime de chuvas, marés e correntes, indicando que a análise dos efeitos subletais e da teratogenicidade em embriões de D. rerio constitui bom parâmetro para avaliações de toxicidade de amostras ambientais.(AU)

The present study used Danio rerio embryos exposed to the elutriates of the estuarine sediments of the Rio Capibaribe, from the rainy and dry periods, where the lethal effects, teratogenic and heart rate were analyzed. Embryotoxicity tests followed the guidelines of OECD 236. Based on the results obtained, heart rate and teratogenicity demonstrated higher sensitivity to the samples. Among the teratogenic effects, the general delay in embryo development was the most frequent effect during the analyzes. These toxic effects changed between the points and between the collection periods. This variation of toxicity may be related to the diversity of activities carried out around this estuary, the influence of rainfall, tides, and currents, indicating the analysis of sublethal effects and teratogenicity in the D. rerio embryos are useful parameters for toxic evaluation of environmental samples.(AU)

Immunohistochemical Analysis of P-gp, LC3-II, and Cathepsin-D Associated with Histological Changes in Fish Liver: from the Impacted Environment to Clean Water

Abstract Herein we evaluated the histopathological alterations and expression patterns of multixenobiotic resistence (MXR) and autophagic proteins in liver samples of fish chronically exposed to anthropogenic contaminants in a highly polluted river, and then again after they had been transferred to good quality water. Two groups were established: euthanized on the day of capture (0 h), and maintained for 30 days in a tank (30 d). The fish of 0 h presented liver with vacuolated and hypertrophic hepatocytes. Also, it was observed strong immunostaining of cathepsin-D, LC3-II and P-gp. Necrosis and apoptosis were also observed throughout the liver. Conversely, the second group (30 d) showed recovery of the liver normal histology and weak immunoreaction of the studied proteins. So, our results indicated that there was a hepatic recovery in the fish kept in good quality water, as showed by the decreased expression of cathepsin-D, LC3-II, and the MXR (P-gp). Therefore, the alterations here observed could be proposed as potential biomarkers to be tested for following the impacts of remediation or mitigation measures to environmental impacts.

Ecotoxicity test as an aid in the determination of copper guideline values in soils / Ensaios de ecotoxicidade como auxílio na determinação de valores orientadores de cobre em solos

ABSTRACT: The process of identifying a contaminated area involves a preliminary assessment consisting of chemical analysis and comparison with guideline values. In Brazil, these values are included in the CONAMA Resolution no. 420/2009, based on chemical analysis and phytotoxicity. The objective of this research was to evaluate the ecotoxicity of copper in two natural soils in the state of Rio de Janeiro, a Haplic Planosol (sandy) and a Red-Yellow Argisol (medium texture), to verify if the values established by the legislation offer protection to the soil fauna. Lethality and reproduction tests were performed with Eisenia andrei worms and Folsomia candida springtails. Results indicated copper values in Planosol as LC50 435 mg kg 1 and EC50 29 mg kg 1 for E. Andrei and LC10 137 mg kg 1 and EC50 117 mg kg 1 for F. candida. In Argisol, these results were LC50 690 mg kg 1 and EC50 61 mg kg 1 for E. andrei, and LC10 42 mg kg 1 and EC50 138 mg kg 1 for F. candida. Values reported are lower than the research value (200 mg kg-1) established by the CONAMA resolution 420/09, indicating that concentrations lower than the limit values may affect these organisms, depending on the type of soil. Worms were more sensitive than springtails to copper contamination, and sandy soil was more susceptible to ecotoxicity due to copper contamination, probably due to the greater bioavailability of the metal. Results of such ecotoxicity tests should be considered in the development of soil guideline values.

RESUMO: O processo de identificação de uma área contaminada envolve uma avaliação preliminar que consiste em análise química e comparação com valores orientadores. No Brasil, esses valores constam na Resolução CONAMA no 420/2009, baseados em análises químicas e fitotoxicidade. O objetivo deste trabalho foi avaliar a ecotoxicidade do cobre em dois solos naturais do Estado do Rio de Janeiro, um Planossolo Háplico (arenoso) e um Argissolo Vermelho-Amarelo (textura média), para verificar se os valores estabelecidos pela legislação oferecem proteção à fauna do solo. Foram realizados ensaios de letalidade e de reprodução com minhocas da espécie Eisenia andrei e com colêmbolos da espécie Folsomia candida. Os resultados indicaram no Planossolo valores de cobre para E. andrei de CL50 435 mg kg-1 e CE50 29 mg kg-1 e para F. candida CL10 137 mg kg-1 e EC50 117 mg kg-1. No Argissolo esse resultado foi para E. andrei CL50 690 mg kg-1 e CE50 61 mg kg-1, e para F. candida CL10 42 mg kg-1 e CE50 138 mg kg-1. Os valores encontrados são menores que o valor de investigação (200 mg kg-1) estabelecidos pela resolução 420/09 do CONAMA, indicando que concentrações menores do que os valores-limite podem afetar esses organismos, a depender do tipo de solo. As minhocas mostraram-se mais sensíveis que os colêmbolos à contaminação por cobre, e o solo arenoso mostrou-se mais suscetível a apresentar ecotoxicidade diante de uma contaminação por cobre, devida, provavelmente, à maior biodisponibilidade do metal. Os ensaios de ecotoxicidade devem ser considerados no desenvolvimento de valores orientadores para solos.

Avaliação ecotoxicológica de efluentes tratados por alagados construídos / Ecotoxicological evaluation of effluents treated by constructed wetlands

RESUMO O objetivo deste trabalho foi avaliar o desempenho de alagados construídos com fluxo subsuperficial horizontal cultivados com as macrófitas aquáticas Eleocharis sp. (junco) e Typha sp. (taboa) na redução da toxicidade de efluentes domésticos. Para isso, foram utilizados ensaios ecotoxicológicos com o microcrustáceo Daphnia similis, a dicotiledônea Lactuca sativa (alface), a monocotiledônea Sorghum vulgare (sorgo) e as macrófitas aquáticas Lemna sp. (lentilha-d'água) e Azolla sp. O efluente doméstico mostrou-se tóxico à Daphnia similis com média de EC50 de 1,3%. Os tratamentos com macrófitas reduziram significativamente a toxicidade do efluente, com médias de EC50 de 73% para o tratamento com junco, 53,17% para o com taboa e 78,25% para o com taboa + junco. O controle (sem macrófitas) também reduziu significativamente a toxicidade, com média de EC50 de 63,13%. Nos ensaios de fitotoxidade, a alface e o sorgo não se mostraram sensíveis ao efluente analisado, embora sejam para outros tipos de efluentes. A macrófita Lemna sp. também não foi sensível ao efluente estudado, no entanto, observou-se a capacidade de identificar, com essa espécie, o potencial eutrofizante do efluente, já que esta se desenvolveu melhor no efluente bruto do que nos tratados. Com a macrófita Azolla sp., foi possível verificar que o efluente bruto apresenta maior potencial eutrofizante se comparado com os tratamentos com junco, taboa e controle, nos quais houve remoção de nitrogênio e fósforo. No entanto, evidenciou-se efeito tóxico para Azolla sp. nos efluentes tratados.

ABSTRACT The research objective was to evaluate the performance of wetlands constructed with vertical sub-surface flow cultivated with Eleocharis sp. (Junco) and Typha sp. (Taboa). For this, ecotoxicological tests were used with the microcrustacean Daphnia similis, with the dicotyledon Lactuca sativa (alface), the monocotyledon Sorghum vulgare (sorgo) and the aquatic macrophytes Lemna sp. (Duckweed) and Azolla sp. The domestic effluent was toxic to Daphnia similis with a mean EC50 of 1.3%. Macrophyte treatments significantly reduced effluent toxicity with EC50 averages of 73% for junco treatment, EC50 53.17% for taboa treatment, and EC50 78.25% for taboa + junco treatment. The control (without macrophytes) also significantly reduced toxicity, with a mean EC50 of 63.13%. In the phytotoxicity tests, lettuce and sorgo were not sensitive to the analyzed effluent, although they were for other types of effluents. The macrophyte Lemna sp. was also not sensitive to the effluent studied. However, it was possible to identify the eutrophic potential of the effluent with this species, since it was better developed in the raw effluent than in treated ones. With the macrophyte Azolla sp., it was possible to verify that the raw effluent has greater eutrophic potential when compared to the treatments with junco, taboa and control, where nitrogen and phosphorus removal was observed. However, toxic effect was observed for Azolla sp. in treated effluents.

Cadmio y alteraciones morfológicas en el rotífero Philodina cf. roseola (Bdelloidea: Philodinidae) y el gusano Aeolosoma hemprichi (Annelida: Aeolosomatidae)

El cadmio es un metal tóxico que produce deformaciones en el zooplancton y es considerado un peligro para el ambiente y la vida acuática. Por ello, utilizamos dos especies de zooplancton nativas de Quintana Roo, México para obtener datos sobre la toxicidad de cadmio, incluyendo la concentración umbral para alteraciones morfológicas observables y el porcentaje de organismos con alteraciones morfológicas en las concentraciones de exposición. Utilizamos el rotífero Philodina cf roseola y el oligoqueto Aeolosoma hemprichi, ya que ambos se alimentan del alga Nannochloropsis oculata. Seguidamente, ambas especies de animales fueron expuestas a un rango de concentración de cadmio de 0.05 (0.047 mg/l, concentración real) a 10.0 mg/l (9.398 mg/l, concentración real) durante 24 h. El CL50 para cadmio en P. cf roseola fue de 0.7 mg/l (0.65 mg/l, concentración real), mientras que en A. hemprichi fue de 3.38 mg/l (3.17 mg/l, concentración real). El cadmio a concentraciones de 0.5 mg/l (0.47 mg/l, concentración real) y exposición menor a 24 h, por un lado, indujo alteraciones morfológicas en la lorica de los rotíferos, deformaciones del pie y constricciones en la parte media del cuerpo. En oligoquetos, por otro lado, observamos daños en la epidermis. La concentración umbral donde las deformaciones aparecieron en rotíferos fue 0.3 mg/l (0.28 mg/l, concentración real) a las 24 h, mientras que en oligoquetos fue a 0.5 mg/l (0.47 mg/l concentración real) en 30 min. Concluimos que claramente el cadmio promueve alteraciones morfológicas en organismos acuáticos, debido a la exposición directa que se añade al medio de cultivo.

Cadmium is a toxic metal for zooplankton that produces deformations. It is also considered an environmental hazard to aquatic life. Since it has a significant effect in some marine organisms, we used two native zooplankton species from Quintana Roo, Mexico to obtain data regarding cadmium toxicity including the threshold concentration for observable morphological alterations and the percentage of organisms with morphological alterations at the exposure concentrations. We used the rotifer Philodina cf roseola and the oligochaeta Aeolosoma hemprichi, since both feed from the algae Nannochloropsis oculata. Both animals were exposed to a cadmium concentration range from 0.05 mg/l (0.047 mg/l, real concentration) to 10.0 mg/l (9.39 mg/l, real concentration) for 24 h. The LC50 for cadmium in P. cf roseola was 0.7 mg/l (0.65 mg/l, real concentration), whereas in A. hemprichi was 3.38 mg/l (3.17 mg/l, real concentration). The exposure of cadmium at 0.5 mg/l (0.47 mg/l, real concentration) for less than 24 h induced morphological alterations in the lorica of rotifers, foot deformations, and constriction in the middle part of the body. In oligochaetes, damage to the epidermis was noted. The threshold concentration where deformations appeared in rotifer was 0.3 mg/l at 24 h, while in oligochaeta was 0.5 mg/l (0.47 mg/l, real concentration) at 30 min. We concluded that cadmium promotes alterations in aquatic organisms due to direct exposure added to the culture medium.

Exposição crônica ao cloridrato de metformina e à glibenclamida causa alterações comportamentais, glicêmicas e de mortalidade em Hemigrammus caudovittatus e Danio rerio / Chronic exposure to metformin chloridrate and glibenclamide causes behavioral, blood glucose and mortality changes of Hemigrammus caudovittatus and Danio rerio

Hemigrammus caudovittatus e Danio rerio foram expostos aos hipoglicemiantes orais (HOs) cloridrato de metformina a 40µg/L e 120µg/L e glibenclamida a 0,13µg/L e 0,39µg/L durante 100 dias. Foram avaliados os efeitos tóxicos dos fármacos em relação ao peso, ao comportamento animal, à glicemia e à mortalidade. H. caudovittatus expostos à menor concentração dos fármacos apresentaram aumento significativo (P<0,05) no evento Respiração Aérea. Ainda, foi observado aumento no comportamento Descansar quando os animais foram expostos à glibenclamida a 0,39µg/L. Em D. rerio expostos ao cloridrato de metformina a 120µg/L, foi observado aumento (P<0,05) no comportamento Descansar. A glibenclamida provocou redução (P<0,05) na glicemia de H. caudovittatus. Ambos os fármacos causaram efeito letal na espécie D. rerio, contudo a glibenclamida foi mais tóxica, causando 100% de mortalidade em 30 dias de exposição. Os animais que vieram a óbito apresentaram congestão nos arcos branquiais e hemorragia. Os HOs foram desenvolvidos para apresentarem efeitos fisiológicos em mamíferos, entretanto efeitos tóxicos foram encontrados nas duas espécies de peixe estudadas. Isso levanta a preocupação sobre possíveis efeitos tóxicos de HOs e sobre quais métodos serão utilizados para a sua degradação no ambiente aquático.(AU)

Hemigrammus caudovittatus and Danio rerio were exposed to oral hypoglycemic drugs (HOs) metformin hydrochloride at 40µg/L and 120µg/L and to glibenclamide at 0.13µg/L and 0.39µg/L during 100 days. Toxic effects of the drugs were evaluated based on weight, animal behavior, blood glucose and mortality. H. caudovittatus exposed to lowest concentration of the drugs showed significant increase (P< 0.05) in the Air breathing event. Furthermore, increase in Rest event was observed when animals were exposed to glibenclamide at 0.39µg/L. An increase (P< 0.05) in the frequency of Rest behavior in the D. rerio exposed to metformin hydrochloride at 120µg/L was observed. Glibenclamide caused decrease (P< 0.05) in the blood glucose of H. caudovittatus. Both drugs caused lethal effect against D. rerio. Nevertheless, glibenclamide was more toxic causing 100% of mortality after 30 days of exposure. The animals that died showed congestion on the branchial arches and hemorrhage. The HOs were developed to have physiological effects in mammals. However, toxic effects were found in both species of fish studied. This raises concerns about possible toxic effects of HOs and what methods will be used for their degradation in the aquatic environment.(AU)