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La agricultura convencional depende de la aplicación de fertilizantes con el fin de lograr mayores rendimientos; sin embargo, es necesario encontrar un equilibrio entre sus beneficios y las alteraciones que pudieran producir a los ecosistemas. Organizaciones internacionales regulan su uso y comercialización teniendo en cuenta la eficacia y seguridad. IHPLUS®, producido por la Estación Experimental de Pastos y Forrajes “Indio Hatuey” (Cuba), ha mostrado ser efectivo en diferentes cultivos y es objeto en este estudio evaluar los efectos sobre la calidad del agua en el bioindicador Poecilia reticulata. Los peces fueron expuestos al producto, en régimen estático durante 96 h, a la concentración efectiva en la agricultura (6 %) o diluido hasta 106 UFC/ml según recomienda la EPA OPPTS 885.4000. Asimismo, se incluyó un grupo tratado con el producto al 6 %, pero esterilizado y un grupo control que no recibió tratamiento alguno. Se observaron durante 30 días posinoculación y se evaluó el peso, la mortalidad y otros efectos subletales. Posteriormente, se determinó la concentración letal media (CL50) y la influencia del pH sobre la mortalidad de los peces. Se pudo comprobar que al 6 % provocó eventos clínicos adversos y efecto letal en el biomodelo. Las lesiones histopatológicas se corresponden tanto para el producto activado como para el inactivado. La CL50 fue de 3.19 %, asociándose la toxicidad al pH ácido y no a la carga microbiana presente en el bioproducto. Se concluye que IHPLUS® es seguro para Poecilia reticulata a concentraciones inferiores al 3 %.

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Religación: Revista de Ciencias Sociales y Humanidades is the property of Religacion: Revista de Ciencias Sociales y Humanidades and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Toxicología is the property of Asociacion Espanola de Toxicologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista ION is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Colombiana de Biotecnología is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bistua: Revista de la Facultad de Ciencias Básicas is the property of Facultad de Ciencias Basicas de la Universidad de Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista CIENCIA UNEMI is the property of Universidad Estatal de Milagro (UNEMI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study of the environmental quality of the largest rivers such as the Paraná, is a challenge for the different disciplines of environmental sciences. Considering that the water quality of the largest rivers is mainly affected by the contributions of pollutants through the tributaries, we evaluate, using a multidisciplinary approach, the environmental quality of the tributaries of the Paraná River in Argentina, whose subbasins are associated with different levels and types of anthropization. We also discussed the aptitude of different diagnostic tools used to study the quality of water courses associated with rural landscapes and proposed a new indicator of easy measurement to quantify the level of anthropization in these environments. We selected 6 sampling sites (SM) related with different level of anthropization, considering agricultural and/or livestock (A/G) and urban or industrial (U/I) activities. The general parameters of water quality were measured in situ, and water and sediment samples were taken for physical, chemical, microbiological and ecotoxicological evaluation. The toxicity was evaluated by a battery of bioassays (Daphnia magna, Hyalella curvispina and Lactuca sativa). The frequency of bioassays that show significant effects correlated positively with anthropization. Lactuca sativa was particularly sensitive to pollutants of A/G origin, while crustaceans, to those from U/I. The combination of U/I and A/G activities increased the toxicological complexity of the watercourses, producing greater adverse effects. Although, in the rural areas the U/I activities represented a scale notably small in relation to A/G, their contribution to the deterioration of the toxicological quality of watercourses appeared significant. [ABSTRACT FROM AUTHOR]

O Brasil possui uma posição de visibilidade na popularização de pesticidas no qual tem ocasionado problemas de saúde pública e ambiental. Assim, a busca por novos inseticidas naturais que atendam diretrizes adequadas são encontrados nas plantas, como é o caso dos compostos clitoriacetal e 6-desoxiclitoriacetal isolados de plantas do gênero Clitoria constituídos de rotenóides com atividade inseticida. Nesse contexto, o objetivo deste estudo consiste na investigação de toxicidade in silico em abelhas A. melífera dos pesticidas clitoriacetal e 6-desoxiclitoriacetal viabilizando a biossegurança destes organismos. Baseando-se nos modelos in silico: BeetoxAl© (toxicidade aguda oral) e docking molecular como critério de avaliação bioquímica. Dessa forma, foi estabelecido que os derivados clitoriacetal e 6-desoxiclitoriacetal apresentam potencial toxicológico por via oral (agudo) devido aos diversos sítios de aceitadores de hidrogênio e baixo valor quantitativo de exposição. E a partir do docking molecular pontua-se que os complexos formados entre os ligantes e proteína da A. melífera apresentam posições tridimensionais similares, mas não exprime nenhuma interação com aminoácidos do sítio de ligação da A. melífera conferindo-os baixa toxicidade. O estudo foi desenvolvido em caráter inicial, ou seja, ainda serão necessário melhoria e aprofundamentos das técnicas aplicadas e ampliações de novos ensaios in silico e in vivo.

Introduction: Small cetaceans are good bioindicators of environmental contamination; however, knowledge about their ecotoxicological status in Central America is scarce. In Panama, access to samples from wild populations to determine the ecotoxicological status of oceanic dolphins is limited; therefore, stranding events provide an alternative for obtaining samples. In April 2016, a rare mass stranding event occurred in the Azuero Peninsula (Pacific coast of Panama), where 60 rough-toothed dolphins (Steno bredanensis) stranded, including ten which died on the beach. Objective: To assess total mercury (THg) concentrations, and δ13C and δ15N stable isotope values in roughtoothed dolphins for the first time in this region. Methods: Nine skin samples were collected from adults, stored in 70 % ethanol, and posteriorly analyzed to determine THg concentrations and stable isotope values. Results: THg concentrations ranged from 4 764 to 18 689 ng g-1 dry weight (dw) (mean = 12 841; SD = 5 083 ng g-1 dw), δ13C values ranged between -16.8 and -15.2 ‰ (mean = -16.2; SD = 0.6 ‰), and d15N values ranged between 14.3 and 15.9 ‰ (mean = 15.0; SD = 0.5 ‰). Conclusions: High THg concentrations reported for this species in the Azuero Peninsula are consistent with values reported for rough-toothed dolphins in other areas worldwide, such as the central-northern Rio de Janeiro State in Brazil and La Guajira in the Colombian Caribbean. Elevated mercury (Hg) concentrations may be related to the rough-toothed dolphin diet, which according to δ15N values found here, appears to be based mainly on high trophic level prey that bioaccumulate more Hg in their tissues compared to lower trophic level organisms. However, additional dietary studies would be required to support these findings. Continuing monitoring of traditional dietary analysis, as well as contamination levels in fish and dolphins, is necessary to understand the dolphins' ecotoxicology in Panama. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O estudo teve por objetivo avaliar um efluente contendo formaldeído tratado por um sistema combinado composto por filtro anaeróbio, biofiltro aerado e um decantador. O sistema operou com tempo de detenção hidráulica de 16 horas, sendo 8 horas para cada reator; a vazão de operação que alimentava o sistema foi de 49,0 mL min-1, totalizando 52,9 L dia-1. O estudo dividiu-se em quatro fases, determinadas pela concentração de formaldeído afluente: 100, 200, 400 e 500 mg HCHO L-1. Para avaliar a eficiência do tratamento, foram realizados ensaios de toxicidade com Girardia tigrina em três pontos de amostragem. Os resultados obtidos para CL50 nas concentrações estudadas de 100, 200 e 400 mg HCHO L-1 variaram de 82,35 a valores não detectados (ND). Na concentração de 500 mg HCHO-1, o efluente tratado foi significativamente tóxico. A espécie demonstrou ser sensível ao efluente nas condições de operação do sistema de tratamento em todo o período de estudo.

Organophosphate insecticides, such as chlorpyrifos, exert their toxicity by inhibiting esterase enzymes, such as acetylcholinesterase (AChE) and carboxylesterase (CbE) in insects and other animals. Therefore, the evaluation of the activity of these enzymes is widely used as a biomarker of animal exposure to these types of compounds in environmental monitoring studies. In the present study, the understanding of these effects was transmitted to students of the Graduate Program in Biodiversity at UNESP, through a practical experiment carried out in the discipline of Ecotoxicology. These concepts were approached through a comparative evaluation between the in vitro inhibition effects of AChE and CbE by the insecticide chlorpyrifos, in brown catfish (Pterygoplichthys anisitsi) of three different size ranges (10-14, 15-19 and 20 -24cm). The results indicated discrepancies between enzymatic activity values between different groups of fish. Also, smaller animals were more sensitive to AChE inhibition by chlorpyrifos, while larger animals were more sensitive to CbE inhibition. In addition to contributing to students' learning, the study brought unpublished data on the sensitivity of brown catfish esterases to chlorpyrifos. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

O comportamento ecotoxicológico de fluidos de perfuração pode ser estudado pela relação entre a ecotoxicidade de um fluido com suas propriedades físico-químicas e a concentração de seus componentes. Por se tratar de uma mistura complexa, os componentes do fluido influenciam de formas diferentes na ecotoxicidade da mistura. De posse de uma base de dados contendo resultados de testes de ecotoxicidade de amostras de fluidos de perfuração conhecidas, pode-se aplicar técnicas de mineração objetivando a previsão e extração de conhecimento, que pode ser empregado em ferramentas de análises de risco e tomada de decisão. Este artigo tem como objetivo elaborar uma revisão sistemática da literatura para responder à questão de pesquisa: qual a previsão do comportamento toxicológico de fluidos de perfuração, conhecida a sua composição e suas propriedades físico-químicas, por meio de técnicas computacionais de análise de dados de testes de ecotoxicidade aguda? Para tanto, foram utilizadas três bases de dados e os resultados mostraram que a toxicologia computacional (in silico) tem sido amplamente utilizada na previsão de toxicidade, contudo não há estudos relacionados a fluidos de perfuração nas bases de dados utilizadas.

Introduction. The drugs for human use cause environmental and non-target organism damage in the aquatic environment. Objective. Evaluate through ecotoxicological tests, an antibiotic and an anxiolytic of intensive use on Artemia franciscana "brine shrimp" and Excirolana braziliensis "marine isopod" were exposed to Oxytetracycline (OX), and Apohyale grandicornis "marine amphipod" was exposed to Alprazolam (AL). Materials and methods. A. franciscana and E. braziliensis individuals were exposed to OX, and A. grandicornis was exposed to AL. The number of living and dead organisms was counted in each of the dilutions at 24 and 48 h of exposure. Results. It was noted in A. franciscana that, at 48 h of exposure, the LC50 (Mean Lethal Concentration) of OX was 31 % more sensitive compared to 24 h of exposure. It was seen in E. braziliensis that, at 48 h of exposure, the LC50 of OX was 93 % more sensitive compared to 24 h of exposure. It was observed in A. grandicornis that, at 48 h of exposure, the LC50 of LA was 69 % higher in sensitive compared to 24 h exposure. The toxicological cataloging for OX in A. franciscana considered this drug as non-toxic and in E. braziliensis moderately toxic. LA in A. grandicornis was moderately toxic. Conclusions. These three bioindicators made it possible to evaluate the toxicity in the aquatic environment of pharmaceutical products of intensive use during the Covid-19 period. [ABSTRACT FROM AUTHOR]

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fipronil is an insecticide and acaricide widely used in agriculture and domestic animals worldwide. Ecotoxicology studies have shown that, even at the low concentrations used on target species, fipronil and its degradation products have a significant impact on non-target species, either by direct toxicity or indirect effects affecting the food chain. The negative effects of fipronil on non-target species of terrestrial and aquatic invertebrates and indirect effects on food chains have led to its use being banned or severely restricted in numerous countries, including all of the European Union, China, and the United States. Some of the species highly susceptible to fipronil are of great economic and ecological importance, including crayfish, brown shrimp, and bees. In particular, the impact on decimating bee hives worldwide is an example of fipronil´s undesirable effects on agriculture. Other species affected by fipronil -for which there are few studies- are biological predators of the same pests controlled by fipronil. Considering all the impacts on non-target species, the commercialization and indiscriminate use of fipronil in agriculture seem irresponsible. In Colombia, as of September 2021 and pressed by local beekeepers, the Instituto Colombiano Agropecuario (ICA) prohibited its use on avocado, coffee, citrus, and passiflower plantations. However, as long as its use is not prohibited in all agricultural applications, farmers could divert its use and continue using it in any other type of plantation. This paper describes the impact of fipronil on some of the beneficial invertebrate species of outmost economic and ecological importance. [ABSTRACT FROM AUTHOR]

Copyright of ESPOCH Congresses: The Ecuadorian Journal of S.T.E.A.M. is the property of Knowledge E DMCC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Among emerging pollutants, the pharma drugs focus a great research interest. Sodium Nitroprusside (SNP) is one of the cyanogens most used as a vasodilator for the treatment of cardiac problems. Due to the increasing expansion and the putative contamination of aquatic environments causes by the mismanagement of pharmacological waste, it is important to carry out ecotoxicological assays to clarify its effect on populations of aquatic invertebrates, which act as bioindicators. Thus, the aim of this study was to evaluate the toxicity of the SNP in the invertebrate Artemia franciscana. So, Artemia franciscana nauplii were subjected to different concentrations of SNP (0-3000 µg/mL) for 24 hours, determining the values of LC20, LC50 and LC80. To determine the antioxidant and detoxifying response of these organisms against to SNP, the activity of different enzymes involved in this process: Superoxide dismutase (SOD), Catalase (CAT), Glutathione peroxidase (GPX), Glutathione reductase (GR), Glucose-6-phosphate dehydrogenase (G6PDH), Glutathione S-transferase (GST), DT-Diaphorase (DTD) was quantified, and the levels of lipid peroxidation, (Malondialdheyde (MDA) and total enzyme antioxidant activity (TEAC). The results denoted the existence of a positive correlation between the dose of SNP used and the activity of the enzymes GPX, GR, GST and G6PDH, as well as TEAC, which has been linked to an increase in antioxidant and detoxifying ability of xenobiotic compounds in such organism against the SNP. However, no significant differences were observed for SOD, CAT and DTD enzymes response, as well as in the levels of lipid peroxidation. This is indicative that the SNP exposure produces the inactivation of these enzymes, showing the time-dependent effect that SNP present in the peroxidation lipid in Artemia franciscana nauplii.

Located in the northern extreme of South America, Colombia is one of the most mercury contaminated countries in the world, a situation that threatens its natural wealth and highly endemic neotropical biodiversity and adds to its multiple environmental and social conflicts. Internationally designated as a Ramsar site, the Ayapel wetland complex registers the catching of 23 % of the fish production of the Magdalena-Cauca macro-basin, while at the same time is under intense alluvial mining pressure. Exposure to two endocrine disruptors [mercury (Hg) and arsenic (As)] was traced in fish for human consumption, water and sediments collected in the central marshes of Ayapel, Escobillas and Paticos. Previously unreported concentrations of arsenic were found in sediments and water. This is quite a relevant finding, since it is a carcinogen and because local rice crops are supplied by the water of the marsh system, which may increase toxicological risk for the people of the region. In addition, 96 % of the fish registered statistically significant contents of both Hg and As. The fish blanquillo (Sorubim cuspicaudus) was found to contain the highest levels of both pollutants, while the bocachico (Prochilodus magdalenae) registered the highest level of Hg in the last 15 years for the studied area. Framed in mercury variation in the macro-basin's ichthyofauna (1993-2020), a warning is issued about unmonitored impacts on food webs and the urgency of intersectoral actions to protect biodiversity and human health. [ABSTRACT FROM AUTHOR]

Se evaluó el riesgo ambiental terrestre de dos gasolinas ecológicas de 90 octanos sobre la lombriz de tierra Eisenia fetida (Savigny, 1826). El parámetro de toxicidad letal evaluado fue la mortalidad, y los efectos subletales fueron seis: movilidad, oscurecimiento, adelgazamiento, estrangulación, fraccionamiento y peso corporal a los 7 y 14 días de exposición. Los organismos fueron expuestos a cinco concentraciones de gasolinas ecológicas de 90 octanos expresadas en base al xileno: 49,5 ug·kg-1, 148,5 ug·kg-1, 346,5 ug·kg-1, 841,5 ug·kg-1 y 2079 ug·kg-1. Las gasolinas ecológicas de 90 octanos (Petroperú y Repsol) en el suelo no presentaron efectos de toxicidad letal (concentración letal media, CL50) en E. fetida. Los efectos subletales fueron inmovilidad, oscurecimiento y adelgazamiento. Se consideró como criterio de comparación el Estándar de Calidad Ambiental para suelos (ECA) para el Perú expresado en xileno (11 mg·kg-1). En base a este ECA, los parámetros más sensibles para la gasolina-Petroperú que ocasionaron riesgo en la lombriz de tierra fueron inmovilidad, oscurecimiento y adelgazamiento en relación a la concentración en la que no se observa efecto (NOEC). Para la gasolina – Repsol, los mismos parámetros mostraron riesgo en función al NOEC; sin embargo, el peso húmedo presentó un riesgo significativo en la lombriz al igual en base a la concentración efectiva media (CE50). La gasolina-Repsol presentó una mayor toxicidad para la lombriz de tierra que la gasolina–Petroperú, y el riesgo ambiental fue mayor para las respuestas subletales.

RESUMO 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.

A poluição oceânica vem ganhando cada vez mais notoriedade, tamanha a frequência da constatação de que muitas espécies aquáticas e regiões (até então preservadas) têm sido afetadas direta ou indiretamente por ações individuais e corporativas. Diante da lacuna existente nos registros relacionados à utilização de graxas em revestimentos instalados em poços de petróleo (tanto onshore quanto offshore), considerando as premissas da ecotoxicologia, este estudo destaca a fragilidade na divulgação dos parâmetros ambientais relacionados a algumas das graxas de estocagem (Kendex OCTG e Jet-LubeKorr-Guard) e descida (Lubrax Lith PM1 e Bestolife 72733) mais utilizadas no Brasil. Considerando a existência de opções que dispensam a utilização de tais produtos químicos durante todo o ciclo de vida dos produtos (tecnologia “dope-free”), o aprofundamento de estudos afins (especialmente testes de toxicidade), bem como a adoção de medidas com menor potencial poluidor nas atividades de construção de poços, são sugeridos.

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Toxicología is the property of Asociacion Espanola de Toxicologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large-scale poisoning events are common to scavenging bird species that forage communally, many of which are in decline. To reduce the threat of poisoning and compensate for other persistent threats, management, including supplemental feeding, is ongoing for many reintroduced and endangered vulture populations. Through a longitudinal study of lead exposure in California condors (Gymnogyps californianus), we illustrate the conservation challenges inherent in reintroduction of an endangered species to the wild when pervasive threats have not been eliminated. We evaluated population-wide patterns in blood lead levels from 1997 to 2011 and assessed a broad range of putative demographic, behavioral, and environmental risk factors for elevated lead exposure among reintroduced California condors in California (United States). We also assessed the effectiveness of lead ammunition regulations within the condor's range in California by comparing condor blood lead levels before and after implementation of the regulations. Lead exposure was a pervasive threat to California condors despite recent regulations limiting lead ammunition use. In addition, condor lead levels significantly increased as age and independence from intensive management increased, including increasing time spent away from managed release sites, and decreasing reliance on food provisions. Greater independence among an increasing number of reintroduced condors has therefore elevated the population's risk of lead exposure and limited the effectiveness of lead reduction efforts to date. Our findings highlight the challenges of restoring endangered vulture populations as they mature and become less reliant on management actions necessary to compensate for persistent threats.

RESUMO 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

El lago Sochagota es un sistema construido que actúa como una laguna de oxidación. Su nivel está regulado, posee afloramiento de agua termomineral y recibe escorrentía de suelos sulfatados ácidos y una porción de agua dulce del río Chicamocha; y descarga en el distrito de riego de Usochicamocha. Al incrementar la concentración de sales termominerales, el sistema entra en tensión, pues la alta salinidad amenaza la biodiversidad y se convierte en fuente de conflictos por el uso del agua en la cuenca. Este trabajo recopiló datos de conductividad, precipitación de treinta años y batimetría, procesados, analizados y modelados, para presentar la variabilidad temporal (periodos contrastantes secos y húmedos) y espacial. De igual forma se realizaron ensayos de ecotoxicidad para evidenciar los posibles efectos de la salinización sobre el ecosistema, la biota y los riesgos asociados con cambios en la hidroclimatología de la zona. Los resultados señalan que el lago es altamente sensible a las disminuciones de precipitaciones que favorecen la acumulación de las sales hidrotermales provenientes de su cuenca y afloramientos, lo que acentúa la eutrofización cultural, lo que puede conducir a fenómenos que afecten el ecosistema y el potencial agropecuario de la zona de influencia.

O lançamento de efluentes domésticos e industriais nos corpos hídricos, introduzem inúmeras substâncias químicas com potencial efeito deletério aos seres vivos, dentre elas os compostos denominados “Contaminantes Emergentes”. Este estudo teve como objetivo apresentar um mapeamento do Quociente de Risco (QR) destas substâncias a partir da distribuição nas bacias hidrográficas brasileiras, baseado em uma revisão bibliográfica em revistas indexadas em bases de dados para artigos publicados até o primeiro semestre de 2020. Ainda, apresenta uma abordagem crítica dos potenciais impactos destes contaminantes à biota aquática, especialmente em espécies ameaçadas. O Quociente de Risco (QR) foi calculado utilizando os menores valores de PNEC (Predicted no-effect concentrations) para água doce disponíveis na base de dados de ecotoxicologia da NORMAN, e as concentrações ambientais medidas (MEC) encontradas em cada artigo para cada composto. Sobre o risco potencial para os ambientes aquáticos, chegou-se em 79 compostos com valores de QR >1, distribuídos em 62 estudos realizados majoritariamente nas bacias hidrográficas que se encontram nas regiões Sul e Sudeste brasileira. Dentre estes compostos o grupo de pesticidas foi o predominante (41) seguido por fármacos (15) e compostos de uso industrial (11), compostos de uso pessoal (7) e hormônios (5). Os hormônios foram o grupo com maiores valores de QR seguido por pesticidas. Os resultados sugerem que contaminantes emergentes podem ter um papel importante na pressão de extinção de espécies. Existe a necessidade de ampliação de estudos relacionados ao tema, principalmente na região Norte e Nordeste, onde ainda são extremamente escassas as informações sobre a presença e as concentrações destas substâncias no ambiente aquático.

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/L for tilapia and 0.1, 0.2, 0.5, 0.7 y 1 µl/L 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 LC50at 96 hours for O. niloticus was 17.49 µl L-1, with a lower 95 % confidence limit of 13.75 µl L-1 and an upper limit of 22.25 µl L-1, whereas for M. olfersii the LC50 at 96 hours was 0.31 µl L-1, with a lower 95 % confidence limit of 0.26 µl L-1 and an upper limit of 0.35 µl L-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. [ABSTRACT FROM AUTHOR]

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Los poliquetos (Annelida) son organismos en íntimo contacto con el sedimento donde viven y el agua sobrenadante. El estrés ambiental genera rápidas respuestas en estos organismos que se refleja en los individuos y sus poblaciones, por lo que se utilizan como indicadores biológicos de disturbios y de calidad ambiental. Los poliquetos han sido ampliamente utilizados en monitoreo ambiental y en bioensayos, y muchos estudios ecotoxicológicos se realizan con poliquetos. En casi todos los hábitats bentónicos estos organismos juegan un papel muy importante en la organización y estructura de las comunidades bentónicas y redes tróficas. Son un ítem fundamental en la alimentación de otros invertebrados y de aves migratorias y peces. Los poliquetos también tienen importancia económica para la industria farmacéutica, y de alimentos concentrados para especies marinas de cultivo (peces y crustáceos), en el campo médico y en la bioingeniería, además de la recreativa (acuarofilia, carnada) y por supuesto para el consumo humano. Varios de los índices de impacto ambiental y calidad ambiental existentes se basan en las características de tolerancia/sensibilidad de los organismos bentónicos, y muchos de ellos son poliquetos. Existen unos pocos trabajos de revisión de estos organismos como indicadores, pero todos en idioma inglés. Este trabajo muestra una actualización de los datos referidos a Latinoamérica y el Caribe, e incluye una amplia revisión bibliográfica.

Introducción: La evaluación de los efectos adversos de los contaminantes sobre los ecosistemas y la predicción de propiedades farmacocinéticas de compuestos, son campos de investigación de gran interés. Objetivos: desarrollar modelos computacionales que permitan la predicción, lo más acertada posible, del potencial ecotoxicológico de sustancias químicas de interés; así como la predicción de propiedades farmacocinéticas. Métodos: Para el desarrollo de los modelos predictivos se recopilaron bases de datos de toxicidad, mecanismos de acción toxica, permeabilidad a través de barreras biológicas y propiedades quirales. Se emplearon técnicas de estadística, técnicas de inteligencia artificial o de machine learning según el objetivo. Asimismo, se emplearon programas reconocidos internacionalmente y programas propios. Resultados: Como resultados más importantes se tuvieron nuevos modelos computacionales que permiten predecir mejor los efectos adversos de los compuestos sobre el medio ambiente y nuevos modelos para predecir el paso a través de membranas biológicas, así como la definición de nuevos descriptores quirales. Los resultados han sido publicados en revistas de alto impacto, presentados en eventos científicos y han obtenidos varios premios tanto nacionales como internacionales. Conclusiones: El trabajo permitió profundizar la colaboración con varias universidades nacionales y extranjeras. Los nuevos modelos desarrollados están a disposición de la comunidad científica internacional.

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. 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. Este resultado sugiere un efecto negativo para la fauna acuática de anuros debido al actual uso desmesurado de este tipo de agroquímicos y su interacción con la temperatura ambiental.

Fêmeas ovadas foram expostas a quatro diferentes concentrações de cromo durante 96 horas. Posteriormente, as fêmeas foram transferidas para água de cultivo (descontaminação) durante oito dias. Na exposição foram observados parâmetros reprodutivos e mortalidade. Na descontaminação foi avaliado o sucesso reprodutivo das fêmeas (tempo para produção de saco de ovos e número de náuplios), desenvolvimento da prole e parâmetros populacionais. Durante a exposição não foram observadas mudanças significativas nos parâmetros avaliados. No bioensaio de descontaminação, as fêmeas do grupo controle demonstraram normalidade no comportamento reprodutivo, enquanto que as fêmeas expostas ficaram desovadas por mais tempo reduzindo a produção de náuplios. Com relação ao desenvolvimento, observou-se um retardo nas transições dos estágios larvais, sobretudo de copepodito para adulto, demonstrando uma menor densidade populacional. Portanto, concentrações subletais de cromo podem prejudicar a fisiologia reprodutiva, retardar o desenvolvimento e diminuir a densidade populacional de Tisbe biminiens.

O processo de industrialização e o crescimento acelerado da população mundial que ocorreu nas últimas décadas colocaram em risco diversos ecossistemas, em especial os aquáticos, que tiveram contato com numerosas substâncias químicas potencialmente tóxicas. Estudos de ecotoxicidade com organismos sensíveis a pequenos desequilíbrios ambientais são estudados de forma crescente com o objetivo de testar substâncias que poderiam representar efeitos tóxicos no organismo humano. Dentro deste grupo, destacam-se os pequenos cnidários do gênero Hydra. Por possuir uma série de características favoráveis, este grupo se consolidou como organismo-teste frente a diversos tipos de espécies. Este trabalho de revisão teve o propósito de reunir as informações mais relevantes sobre a importância dos testes de ecotoxicidade e as vantagens e desvantagens da utilização de espécies do gênero Hydra em tais estudos.

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. [ABSTRACT FROM AUTHOR]

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