Ecotoxicological effects of commercial herbicides on the reproductive system of aquatic arthropod Limnocoris submontandoni (Hemiptera: Naucoridae) / Efeitos ecotoxicológicos de herbicidas comerciais no sistema reprodutivo do artrópode aquático Limnocoris submontandoni (Hemiptera: Naucoridae)

Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.

Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.

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.

Exposure of Artemia salinato glyphosate and bioremediation by isotherapy

Artemia salina, an ecotoxicity bioindicator, isa microcrustacean belonging to the order Anostraca. Glyphosate is an herbicide widely used to control weeds. However, its intoxication can cause serious damage to human health and the balance of the environment, given its effects as an endocrine disruptor.Objective:verify the possible protection of the artemia exposed to glyphosate by the addition of its isotherapic into water, by means of the evaluation of the behavioral and morphological features of nauplii and of the physical properties of remedies andtreated water, to elucidate the involved mechanisms. Methods:Artemia salinacysts were kept in culture bottles containing artificial seawatercontaining glyphosate at LC 10 (lethal concentration 10%), to promote hatching within 48 hours. The isotherapic preparations were inserted in each bottle in a 10% of the total water volume. Part of the nauplii was distributed in transparent tubes, being 10 nauplii per tube and 6 tubes per group, for behavioral analysis, and part were collected for a detailed morphological analysis, under an optical microscope. About 80 to 270 nauplii were analyzed per group. The reserved water was divided into aliquots for physicochemical analysis, that is, evaluation of the water dipole behavior by Cartwright ́s method.Results:Gly 6cH presented selective effects on nauplii hatching (p=0.02) and on defected/healthy ratio (p=0.001), representing some protective action. This result was dependent of the salinity of water and presented correspondence with the effects on solvatochromic dyes, indicating that charges and ions can be critical factors involved in the mechanism of action. We concluded that the use of isotherapics could be a plausible tool to reduce the environmental impact of the indiscriminate use of glyphosate, since these results can be reproduced in further studies.

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.

Ecotoxicología ¿Cómo afecta a las comunidades faunísticas de las playas del Pacífico de Guatemala? / How ecotoxicology affect the fauna on the Pacific Guatemala's beaches?

La ecotoxicología estudia los efectos de los contaminantes químicos producidos por acción antropogénica en los diferentes ecosistemas. Las playas, son un ecosistema de interés, ya que en estas ocurre una gran cantidad de sedimentación y por lo tanto tienen la capacidad de acumular significativas concentraciones de contaminantes químicos. En Guatemala, las playas del Pacífico son un sujeto ideal para el estudio ecotoxicológico, debido a la fuerte actividad agrícola que ocurre en la parte alta del litoral que causa el uso frecuente de contaminantes químicos. Los contaminantes químicos con más uso son los insecticidas y entre ellos destacan los compuestos organoclorados y el metil paratión, muy utilizados por su alta efectividad en el control de plagas agrícolas. El uso constante de estos compuestos causa que sean depositados en el sedimento que forma las playas, causando que sean absorbidos por organismos de todos los niveles tróficos, desde productores primarios como plancton hasta consumidores secundarios como reptiles. Regular el uso de estos compuestos es de interés común, debido a los impactos negativos que pueden acarrear sobre los ecosistemas costeros en donde ocurre una gran actividad tanto comercial, como recreativa por parte de las comunidades costeras. Mitigar el impacto de estos compuestos solo será posible si los actores que inciden en toda el área litoral del Pacífico toman conciencia de la potencial degradación de las playas y la importancia de su función tanto para las actividades antropogénicas diarias como para la convergencia ecológica de las múltiples especies que dependen de las mismas para su supervivencia.

Ecotoxicology studies the effect of chemical pollutants produced by anthropogenic action on different ecosys-tems. Beaches are an ecosystem of interest, since a large amount of sedimentation occurs on these places and therefore they have the capacity to accumulate significantly higher concentrations of chemical pollutants compared to terrestrial or aquatic ecosystems. In Guatemala, the beaches in the Pacific coast are an ideal subject for ecotox-icological studies, due to the strong agricultural activity occurring in the highlands that produces a great amount of chemical pollutants and the by-products end up in the beaches as a consequence of pluvial and rivers runoff activity. The most widely used chemical are insecticides and among them, organochlorine compounds and methyl parathion stand out, widely used in part, due to their high effectiveness in pest control. The constant use from these compounds causes them to be absorbed by organisms in all trophic levels, from primary producers to secondary consumers. Regulating the use of these compounds is of common interest, because of the negative impacts on coastal ecosystems where there occurs great commercial and recreational activity from coastal communities. Mitigating the impact of these compounds will only be possible if actors influencing the Pacific littoral area, become aware of the potential beach destruction and the importance of their function both for daily anthropogenic activities and ecological convergence of multiple species that depend on the beaches for their survival.

New Insights into the Gametogenesis of Biomphalaria glabrata (Mollusca, Gastropoda, Pulmonata): Implications for Histopathological Assessment

Abstract The reproductive system has a fundamental role in population dynamics and several reproduction strategies have been shaped by the environment over time. Many environmental pressures are generated by releasing pollutants, as endocrine disruptors, that can affect the reproductive system of individuals, among them invertebrates. The freshwater snails Biomphalaria spp. are used as biomonitor in several ecotoxicological studies; however, there are few studies about gametogenesis and morphology of reproductive snail cells, which could be used as a new biomarker. In this sense, the current study aims to characterize Biomphalaria glabrata gametogenesis, bringing new histomorphometric parameters for germinative cells. Results showed that the hermaphrodite tissue is formed by several acini with simple pavement epithelium with germinative and somatic cells. Oogenesis was classified into five developmental stages (OI to OV) according to diameter, nucleus area, total area, and follicular cell development, and then classified into previtellogenic and vitellogenic oocytes. The spermatogenesis was classified into spermatogonia (Spg), spermatocytes (Spc) and spermatids that were subdivided into five stages (Spt I to Spt V) according to cytoplasm losing, and nucleus spiralization along with Sertoli cells development. Thus, the present study highlights the gametogenesis of B. glabrata with new histomorphometric parameters, which can be an important tool for ecotoxicological and molluscicidal developmental further studies.

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.

Evidence of mutagenic and lethal effects of herbicides on Amazonian frogs

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. (AU)

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 das nanopartículas de Óxido de Zinco (NPs ZnO) em alguns aspectos da sobrevivência, reprodução e desenvolvimento de Biomphalaria glabrata (Say, 1818) (Gastropoda: Pulmonata) / Effects of Zinc Oxide Nanoparticles (NPs ZnO) on some aspects of the survival, reproduction and development of Biomphalaria glabrata (Say, 1818) (Gastropoda: Pulmonata)

A nanotecnologia representa uma tendência chave na ciência e tecnologia do século XXI. As nanopartículas de óxido de zinco (NPs de ZnO) estão entre as mais utilizadas devido a sua capacidade de refletir, absrover e dispersar a radiação ultravioleta. A partir da sua larga utilização em fotoprotetores, estas nanopartículas podem ser liberadas em efluentes e águas residuais e os ecossistemas aquáticos se tornam alvos diretos da contaminação por estes xenobióticos. A avaliação do impacto biológico das NPs de ZnO se torna de grande importância na área de Ecotoxicologia. Neste trabalho, foram analisados os efeitos das NPs de ZnO na sobrevivência, reprodução, sistema imune e nas alterações bioquímicas por estresse oxidativo em Biomphalaria glabrata. As nanopartículas foram caracterizadas quanto ao tamanho, índice de polidispersão e potencial zeta. O tamanho médio nas NPs de ZnO utilizadas neste estudo foi de 34,2 nm. Foram realizados testes agudos, 48h de exposição para determinar as concentrações letais e subletais (CL10, CL30, CL50, CL90). Para avaliar os efeitos das NPs de ZnO na atividade reprodutiva, caramujos B. glabrata, foram expostos a concentrações subletais em diferentes períodos (7 e 21 dias). Após a exposição, a fecundidade e fertilidade de B. glabrata foi afetada de forma significativa em relação ao grupo controle.

Os resultados demonstraram um efeito tempodependente e concentração-dependente. A partir destes resultados, fez-se importante a realização de um teste crônico, 4 semanas de exposição, para avaliar o potencial de reversibilidade da atividade reprodutiva de caramujos expostos as concentrações de 1 e 2 mg L-1 . Os caramujos só apresentaram recuperação da atividade reprodutiva após a exposição a menor concentração, 1 mg L-1 . Testes agudos também foram realizados a fim de avaliar a viabilidade celular e quantificar espécies reativas de oxigênio (Peróxido de Hidrogênio) envolvidas no estresse oxidativo em diferentes tecidos (massa cefalopediosa e visceral, hemolinfa e glândula digestiva) de B. glabrata. A exposição aguda às NPs de ZnO alterou o perfil de hemócitos dos caramujos, com uma tendência ao aumento na população de granulócitos. Concentrações subletais (1, 2 e 6 mg L-1 ) foram capazes de induzir um aumento no nível de peróxido de hidrogênio em amostras de massa cefalopediosa e visceral (partes moles), glândula digestiva e hemolinfa. Este trabalho também avaliou o efeito das NPs de ZnO em diferentes estágios de vida de B. glabrata. Neonatos e massas ovígeras foram expostos a concentrações subletais e foram realizados testes agudos e crônicos. Os resultados indicaram que os estágios iniciais de vida apresentam uma sensibilidade maior do que os caramujos adultos.

A alta taxa de mortalidade dos embriões e neonatos pode siginifcar uma alteração na população desta espécie e consequentemente, implicações ecológicas. Os dados obtidos evidenciam a necessidade da utilização de endpoints mais sensíveis que a mortalidade de organismos adultos. A alteração de processos fisiológicos primordiais como a atividade reprodutiva, não representam efeitos apenas para a população de moluscos B. glabrata, mas podem representar um efeito em todo o ecossistema. Isso porque os moluscos estão associados a diferentes níveis tróficos e representam um elo na cadeia trófica. Alem disso, são responsáveis pela ciclagem de nutrientes, sendo considerados detritívoros-herbivoros. O protocolo básico deste trabalho poderá vir a ser empregado como ferramenta importante, já que as avaliações ecotoxicológicas dispõem de metodologias eficientes para análise da saúde ambiental e dos ecossistemas aquáticos. (AU)

Metal evaluation and ecotoxicological bioassays using Chironomus xanthus in sediments of triângulo mineiro watercourses / Avaliação de metais e bioensaios ecotoxicológicos utilizando Chironomus xanthus em sedimentos de cursos de água do triângulo mineiro

This study aimed to evaluate metal contamination in sediments of the Triângulo Mineiro watercourses and also analyze the toxicity of the sediments using Chironomus xanthus larvae, as test organisms. We collected sediments from three streams (P1, P2 and P3) and collected sediments in three points of the Uberabinha River (P4, P5 and P6). We analyzed Cu, Cr, Mn, Mg and Zn, and also performed acute and chronic toxicity tests. Acute tests were categorized into toxic (death > 50%), toxicity signs (10 < mortality < 50%) and non-toxic (mortality < 10), according to common protocols. In the chronic toxicity tests, the surviving larvae were stored for body size measurements. Of the five metals analyzed, all were found in the six sampling points, but only Cu and Zn were present at higher levels than the "Threshold Effect Level" (TEL). The sediments of the six sites have some level of toxicity and the mortality in the acute and chronic toxicity tests was 100%. No statistically significant differences, between treatment and the control were found in the larval growth. Based on the metal contamination and the toxicity bioassay results, we consider it important to monitor sediments and to evaluate changes in land use in the adjacent water courses. (AU)

Este estudo objetivou avaliar a contaminação de metais nos sedimentos de cursos de água do Triângulo Mineiro e também analisar a toxicidade desses sedimentos utilizando larvas de Chironomusxanthus como organismo teste. Foram coletados sedimentos de três riachos (P1, P2 e P3) e também em três pontos do rio Uberabinha (P4, P5 e P6). Foram analisados Cu, Cr, Mn, Mg e Zn, e também realizados testes de toxicidade aguda e crônica. As amostras submetidas aos testes agudos foram categorizadas como tóxicas (mortalidade > 50%), evidências de toxicidade (mortalidade entre 10% e 50%) e não tóxicas (mortalidade <10%). Nos testes de toxicidade crônica, as larvas sobreviventes foram armazenadas para medidas do tamanho corporal. Dos cinco metais analisados, todos foram encontrados nos seis pontos amostrais, mas apenas Cu e Zn estavam presentes em níveis mais altos que TEL - Threshold Effect Level. Os sedimentos dos seis locais apresentam toxicidade ou indício de toxicidade e a mortalidade nos testes de toxicidade aguda e crônica foi de 100%. Não foram encontradas diferenças estatisticamente significativas, entre o tratamento e o controle, no crescimento larval. Com base na contaminação verificada e nos resultados dos bioensaios de toxicidade, consideramos importante monitorar os sedimentos e as mudanças no uso dos solos adjacentes aos cursos de água. (AU)

Comparison of nuclear abnormalities in Astyanax bifasciatus Cuvier, 1819 (Teleostei: Characidae) of two sections of rivers from the middle Iguaçu / Comparação de anormalidades nucleares em Astyanax bifasciatus Cuvier, 1819 (Teleostei: Characidae) de dois trechos de rios do médio Iguaçu

Most changes in water bodies are result of human activities that have the potential to undermine the environmental integrity of aquatic ecosystems. Changes in genetic material can be evidenced by the frequency of nuclear abnormalities in fish blood cells, in response to genotoxic agents even at low concentrations. Thus, we aimed at comparing the frequencies of nuclear abnormalities of fish kept in acclimation, with fish collected in Timbó river (Santa Cruz do Timbó, Santa Catarina State), under low anthropogenic interference, and fish collected in Iguaçu river (União da Vitória, Paraná State), a polluted river. The highest frequency of changes in nuclear morphology of fish erythrocytes was found in the urbanized area around the Iguaçu river, while, the fish collected in areas with preserved riparian forest surrounding the Timbó river and acclimated fish showed no morphological changes. Our results suggest that genotoxic compounds in the Iguaçu river are acting as stressors to aquatic communities, especially fish. In addition, the absence of nuclear abnormalities in fish from the Timbó river suggests that rivers without significant environmental changes can serve as reference point for comparative studies of genetic modifications for the species studied.

A maioria das alterações dos corpos hídricos é resultante das atividades antrópicas que são prejudiciais à integridade ambiental dos ecossistemas aquáticos. Alterações no material genético podem ser evidenciadas pela frequência de anormalidades nucleares em peixes, em resposta a agentes genotóxicos, mesmo em baixas concentrações. Dessa forma, o estudo consistiu em comparar as frequências de anormalidades nucleares de peixes mantidos em aclimatação, com peixes coletados no rio Timbó (Santa Cruz do Timbó, Estado de Santa Catarina), local com pouca interferência antropogênica e, peixes coletados no rio Iguaçu (União da Vitória, Estado do Paraná), um rio poluído. As maiores frequências de alterações na morfologia nuclear dos eritrócitos dos peixes foram visualizadas na área urbanizada ao redor do rio Iguaçu, quando comparados com os peixes coletados em área com mata ciliar preservada, no rio Timbó, e os peixes aclimatados, que não apresentaram alterações morfológicas. Esses resultados sugerem que há compostos genotóxicos no trecho médio do rio Iguaçu que são estressores para os peixes. Além disso, a não observação de anormalidades nucleares no rio Timbó sugere que rios sem alterações ambientais podem servir como ponto de referência para estudos comparativos de modificações genéticas para a espécie estudada.

Legislación del benceno y el cadmio en la calidad del aire entre países / Legislation of benzene and cadmium in air quality between countries / Legislação do benzeno e do cádmio na qualidade do ar entre países

Introducción: la Agencia Internacional de Investigación del Cáncer (IARC) clasifica al benceno y al cadmio como agentes que se asocian al cáncer en seres humanos dentro del grupo 1, con mayor solidez y evidencia. Objetivo: comparar las concentraciones atmosféricas legisladas en siete países con la legislación colombiana para generar recomendaciones frente a esta. Método: se realizó una búsqueda en Internet con palabras clave en español, inglés, alemán y portugués, sobre la legislación en calidad del aire en países con mayor desarrollo económico e industrial en el mundo: Brasil, Estados Unidos, Alemania, Reino Unido, Nueva Zelanda y Japón. Resultados: se encontraron los siguientes valores parabenceno: Japón, 3 µg/m³; Nueva Zelanda, 3,6 µg/m³; Colombia, Reino Unido y Alemania, 5 µg/m³; ni Estados Unidos ni Brasil tienen legislación al respecto, y la Organización Mundial de la Salud (OMS) no recomienda valor límite. Para cadmio se encontraron los siguientes valores: OMS, 0,001µg/m³; Reino Unido, Alemania y Colombia, 0,005 µg/m³; ni Estados Unidos, ni Brasil, ni Japón ni Nueva Zelanda tienen reglamentación al respecto. Conclusión: la regulación de los mencionados contaminantes es necesaria, por sus efectos en la salud; los procesos históricos, el grado de desarrollo socioeconómico y las diferencias culturales influyen en la legislación de cada país; Colombia debe propender por una legislación estricta para que las concentraciones sean cero, pues en la toxicología ambiental nunca se especifica que una dosis es inofensiva para sustancias cancerígenas

Introduction: The International Agency for Research on Cancer considers as Group 1 carcinogens to air pollutants to the benzene is a volatile organic compound and the cadmium is a heavy metal. Objective: To compare the atmospheric concentrations legislated in seven countries with the Colombian laws to generate recommendations on current regulations. Methods: A search conducted online with keywords in English, Spanish, German and Portuguese of legislation on air quality in countries with greater economic and industrial development: Brazil, USA, Germany, United Kingdom, New Zealand and Japan. Results: The values for benzene were: Japan 3 µg/m³, New Zealand 3.6 µg/m³, Colombia, United Kingdom and Germany 5 µ g/m³; United States and Brazil do not have legislation and World Health Organization not have recommendation over limit value, and for cadmium the World Health Organization say 0.001 µg/m³, United Kingdom, Germany and Colombia 0.005 µg/m³; United States, Brazil, Japan and New Zealand have no legislation. Conclusion: The rules this contaminants is necessary for yours effects for the human health; the historical, socio-economic and cultural development influence the legislation differences of each country; Colombia must tend to have strict legislation that commits governmental entities and work in terms of time so that the concentration to zero, as in environmental toxicology never specifies that a dose harmless to carcinogens

Introdução: A Agência Internacional de Pesquisa sobre o Câncer considera os carcinogênicos do grupo 1 como poluentes atmosféricos ao benzeno, que é um composto orgânico volátil e ao cádmio como metal pesado. Objetivo: Comparar as concentrações atmosféricas legisladas em 7 países com a legislação colombiana para gerar recomendações contra ela. Métodos: Foi realizada uma pesquisa na Internet com palavras-chave em espanhol, inglês, alemão e português da legislação sobre qualidade do ar em países com maior desenvolvimento econômico e industrial: Brasil, Estados Unidos, Alemanha, Reino Unido, Nova Zelândia e Japão. Resultados: Os seguintes valores foram encontrados para o benzeno: Japão µ g/, Nova Zelândia 3,6 µg/m³, Colômbia, Reino Unido e Alemanha 5 µg/m³; Os Estados Unidos e o Brasil não possuem legislação e a Organização Mundial da Saúde não recomenda um valor limite; para o cádmio foram encontrados os seguintes valores: Organização Mundial de Saúde 0,001 µg/m³, Reino Unido, Alemanha e Colômbia 0,005 µg/m³; Os Estados Unidos, o Brasil, o Japão e a Nova Zelândia apresentam ausência de regulamentação. Conclusão: A regulação destes poluentes é necessária devido aos seus efeitos na saúde; Processos históricos, desenvolvimento socioeconômico e diferenças culturais influenciam a legislação de cada país; A Colômbia deve se esforçar para ter uma legislação rígida para que as concentrações sejam zero, já que na toxicologia ambiental nunca especifica que uma dose é inofensiva para substâncias carcinogênicas

Reminiscing on 35 years with Environmental Toxicology in Korea

No abstract available.

Epigenetic profiling to environmental stressors in model and non-model organisms: Ecotoxicology perspective

Epigenetics, potentially heritable changes in genome function that occur without alterations to DNA sequence, is an important but understudied component of ecotoxicology studies. A wide spectrum of environmental challenge, such as temperature, stress, diet, toxic chemicals, are known to impact on epigenetic regulatory mechanisms. Although the role of epigenetic factors in certain biological processes, such as tumourigenesis, has been heavily investigated, in ecotoxicology field, epigenetics still have attracted little attention. In ecotoxicology, potential role of epigenetics in multi- and transgenerational phenomenon to environmental stressors needs to be unrevealed. Natural variation in the epigenetic profiles of species in responses to environmental stressors, nature of dose-response relationships for epigenetic effects, and how to incorporate this information into ecological risk assessment should also require attentions. In this review, we presented the available information on epigenetics in ecotoxicological context. For this, we have conducted a systemic review on epigenetic profiling in response to environmental stressors, mostly chemical exposure, in model organisms, as well as, in ecotoxicologically relevant wildlife species.

Epigenetic profiling to environmental stressors in model and non-model organisms: Ecotoxicology perspective

Epigenetics, potentially heritable changes in genome function that occur without alterations to DNA sequence, is an important but understudied component of ecotoxicology studies. A wide spectrum of environmental challenge, such as temperature, stress, diet, toxic chemicals, are known to impact on epigenetic regulatory mechanisms. Although the role of epigenetic factors in certain biological processes, such as tumourigenesis, has been heavily investigated, in ecotoxicology field, epigenetics still have attracted little attention. In ecotoxicology, potential role of epigenetics in multi- and transgenerational phenomenon to environmental stressors needs to be unrevealed. Natural variation in the epigenetic profiles of species in responses to environmental stressors, nature of dose-response relationships for epigenetic effects, and how to incorporate this information into ecological risk assessment should also require attentions. In this review, we presented the available information on epigenetics in ecotoxicological context. For this, we have conducted a systemic review on epigenetic profiling in response to environmental stressors, mostly chemical exposure, in model organisms, as well as, in ecotoxicologically relevant wildlife species.

Reminiscing on 35 years with Environmental Toxicology in Korea

No abstract available.

Ecotoxicidad de nanopartículas metálicas y superparamagnéticas de óxido de hierro en dos especies / Ecotoxicity of metalic and superparamagnetics iron oxide nanoparticles in two species

Introducción: la nanotecnología y el empleo de materiales a nano escala son un área relativamente nueva de la ciencia y la tecnología con un gran crecimiento en el mercado global. Muchos de los productos no cuentan con estudios que garanticen su uso seguro, tanto para el hombre como para los ecosistemas. Los estudios ecotoxicológicos permiten evaluar los efectos de un determinado xenobiótico sobre especies representativas de los diferentes compartimentos ambientales. Objetivo: evaluar los efectos tóxicos de nanopartículas de Ag, Au, Ag/Ag y superparamagnéticas de óxido de hierro, en dos especies bioindicadoras de los ecosistemas terrestre y acuático. Métodos: como parte de los estudios de seguridad se realizaron ensayos de toxicidad aguda por contacto en lombriz de tierra de la especie Eisenia andrei, con una duración de 96 horas y estudios en anfibios de la especie Osteopillus septentrionales en diferentes etapas del desarrollo (embrionario y larval). Se evaluó la ocurrencia de mortalidad y de efectos tóxicos, en el caso del ensayo en lombriz de tierra; se determinó además la viabilidad celular. Resultados: los efectos tóxicos más significativos en el caso de la lombriz de tierra fueron, la ocurrencia de alteraciones fisiológicas y conductuales al ser expuesta a NPs de Ag de 3 nm y superparamagnéticas de óxido de hierro, estas últimas provocaron citotoxicidad a la concentración 1,38 mg/mL. En el caso de los anfibios se evidenció toxicidad en NPs de Ag 3 nm y superparamagnéticas de óxido de hierro. Conclusiones: todas las nanopartículas mostraron efectos tóxicos en las especies bioindicadoras evaluadas(AU)

Introduction: Nanotechnology and the use of nanoscale materials are a relatively new area of science and technology with big growth in the global market. Many of these products don't have studies that guarantee their safe use, both for man and for ecosystems. Ecotoxicological studies allow the evaluation of the effects of a particular xenobiotic on representative species of the different environmental compartments. Objective: To evaluate the toxic effects of nanoparticles of Ag, Au, Ag / Ag and super paramagnetic iron oxide in two bioindicators of terrestrial and aquatic ecosystems. Methods: Acute contact toxicity tests were carried out on ground worm of the Eisenia andrei species, with a duration of 96 hours and studies on amphibians of the species Osteopillus septentrionales at different stages of development (embryonic and larval). The occurrence of mortality and toxic effects was evaluated in the case of earthworm test; cell viability was also determined. Results: The most significant toxic effects in the case of earthworms were the occurrence of physiological and behavioral alterations when exposed to 3 nm Ag of superparamagnetic iron oxide nanoparticles, where the latter caused cytotoxicity at concentration of 1.38 mg / mL. In the case of amphibians, toxicity was evidenced in Ag 3 nm nanoparticles and superparamagnetic iron oxide. Conclusions: All nanoparticles showed toxic effects in the evaluated bioindicator species(AU)

Aspectos biológicos de Tetranychus ludeni Zacher, 1913 (Acari: Tetranychidae) alimentados com folhas de batata-doce pulverizadas com o 2,4-D / Biological aspects of Tetranychus ludeni Zacher, 1913 (Acari: Tetranychidae) fed on sweet potato leaves sprayed with 2,4-D

Batata-doce [Ipomoea batatas (L.) Lam.] apresenta grande versatilidade de usos no Brasil. Com a ampliação das áreas de cultivo, essa espécie estará sujeita à contaminação por herbicidas. Eventualmente, organismos não alvos podem ser expostos aos resíduos. O objetivo deste trabalho foi avaliar aspectos biológicos do ácaro Tetranychus ludeni alimentado com folhas de batata-doce pulverizadas com diferentes doses do herbicida 2,4-D. O experimento foi conduzido no Laboratório de Controle Biológico da Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), em Diamantina, Minas Gerais. Foram utilizadas 175 fêmeas de T. ludeni e 6 doses de 2,4-D, em g.ha-1 (8,06; 20,15; 40,30; 80,60; 201,50; e 806,00), mais o tratamento-controle com água destilada. Adotou-se delineamento inteiramente casualizado, com sete tratamentos e cinco repetições, contendo cinco fêmeas de T. ludeni em cada repetição. Foram avaliados a mortalidade inicial do ácaro em 24 h, o número de ovos, as ninfas e a longevidade das fêmeas. Os dados foram submetidos à análise de variância, sendo as médias significativas analisadas pelo teste de Duncan. Observou-se que doses maiores desse herbicida podem aumentar a mortalidade e reduzir a longevidade das fêmeas de T. ludeni.(AU)

Sweet potato [Ipomoea batatas (L.) Lam.] presents great versatility of uses in Brazil. With the expansion of crop areas, this species is subject to contamination by herbicides. Eventually, non-target organisms can be exposed to residues . The aim of this study was to evaluate biological aspects of the mite Tetranychus ludeni fed on sweet potato leaves sprayed with different doses of the herbicide 2,4-D. The experiment was conducted at the Biological Control Laboratory of Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), Diamantina, Minas Gerais, Brazil. Altogether, 175 females of T. ludeni and six doses of 2,4-D, in g.ha-1 (8.06, 20.15, 40.30, 80.60, 201.50, and 806,00) were used, plus the control done with distilled water. It was adopted a completely randomized design with seven treatments and five replications with five females each. Early mortality of T. ludeni (24 h), the number of eggs, nymphs and longevity of females were evaluated. Data were subjected to analysis of variance, being the significant mean analyzed by Duncan test. It was observed that high doses of the herbicide may increase the mortality and decrease longevity of females of T. ludeni.(AU)