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In ecotoxicological assays, previously selected and standardized organism tests are exposed to an environmental sample. Some species of the Chironomus genus have been extensively used in ecotoxicological assays. Among these, Chironomus tentans is usually utilized in the USA and Chironomus sancticaroli in Brazil. We conducted ecotoxicological bioassays to compare a population of C. sancticaroli, kept for 6 years under laboratory conditions, with a sylvatic population of the same species, collected in the field. The aim was to test the hypothesis that populations of C. sancticaroli, maintained in the laboratory for long periods, could have a different response to stressors/substances. We analyzed the responses of C. sancticaroli for potassium chloride, zinc chloride, potassium dichromate, linear alkylbenzene sulphonate (LAS) and caffeine. The results showed no significant differences between the two populations in the analyses and seems to indicate the possible use of C. sancticaroli from populations kept in the laboratory for long periods.

Submitted by Daniela Camargo da Palma (daniela.palma@unesp.br) on 2021-04-21T01:26:43Z No. of bitstreams: 1 Dissertação mestrado - Daniela Camargo da Palma - versão final 09-04-21.pdf: 8365058 bytes, checksum: 45e8698be73c2667d8513adc563a7936 (MD5) Approved for entry into archive by Roberta Honorato Goria (roberta.goria@unesp.br) on 2021-04-23T14:26:30Z (GMT) No. of bitstreams: 1 palma_dc_me_soro.pdf: 8365058 bytes, checksum: 45e8698be73c2667d8513adc563a7936 (MD5) Made available in DSpace on 2021-04-23T14:26:30Z (GMT). No. of bitstreams: 1 palma_dc_me_soro.pdf: 8365058 bytes, checksum: 45e8698be73c2667d8513adc563a7936 (MD5) Previous issue date: 2021-02-10 As pressões antrópicas que causam impacto direto nos reservatórios de abastecimento de água acarretam o aumento de nutrientes e contribuem para o processo de eutrofização artificial. Esse acréscimo de matéria orgânica acarreta o crescimento da população de organismos produtores, tais como as algas, tornando necessário a utilização de algicidas como o sulfato de cobre para o auxiliar o controle desses organismos. A utilização desse algicida, pode impactar na concentração desse metal no sedimento. Os testes ecotoxicológicos são utilizados no controle desses ecossistemas e contribuem na observação das respostas biológicas diante das condições físicas e químicas do ambiente, portanto, são extremamente necessários para o monitoramento da qualidade ambiental. Nesse contexto o objetivo deste trabalho foi avaliar os efeitos da toxicidade aguda (96h) e subcrônica no período de 10 dias, em larvas de Chironomus sancticaroli, expostas ao sedimento dos reservatórios de Itupararanga-Sorocaba e Rio Grande-São Paulo para análise da letalidade e do comprimento da cápsula encefálica em relação a concentração de metais Cr, Cu, Ni, Pb e Zn no sedimento. A análise da concentração de metais foi realizada nos dois reservatórios e seus valores comparados ao permitido pela Resolução CONAMA 454/2012, pelo Conselho Canadense do Ministério de Meio Ambiente e pelos valores de referência. O reservatório de Itupararanga apresentou concentrações abaixo de Cu, Ni, Pb e Zn e valor acima do TEL (Threshold Effect Level) de Cr , enquanto o reservatório Rio Grande apresentou valores acima do PEL (Probable Effect Level) para o Cu e para o Pb. Os reservatórios tiveram sua heterogeneidade confirmada com a ACP (Análise de Componentes Principais), com atuação direta da concentração Cu e de a letalidade, principalmente dos pontos do reservatório Rio Grande, RG 4 e RG 9. Os resultados demonstraram que o reservatório Rio Grande apontou índice de toxicidade muito acima do PEL, principalmente em relação ao Cu, ocasionando a letalidade das larvas de Chironomus sancticaroli, o que evidencia a necessidade do monitoramento dos reservatórios. Anthropic pressures that directly impact water supply reservoirs cause an increase in nutrients and contribute to the process of artificial eutrophication. This increase in organic matter causes the growth of the population of producing organisms, such as algae, making it necessary to use algicides such as copper sulfate to help control these organisms. The use of this algaecide can impact the concentration of this metal in the sediment. The ecotoxicological tests are used in the control of these ecosystems and contribute to the observation of biological responses to the physical and chemical conditions of the environment, therefore, they are extremely necessary for the monitoring of environmental quality. In this context, the objective of this work was to evaluate the effects of acute (96h) and subchronic toxicity over a period of 10 days on Chironomus sancticaroli larvae exposed to the sediment of the Itupararanga-Sorocaba and Rio Grande-São Paulo reservoirs to analyze the lethality and the length of the brain capsule in relation to the concentration of metals Cr, Cu, Ni, Pb and Zn in the sediment. The analysis of the concentration of metals was performed in both reservoirs and their values compared to that allowed by CONAMA Resolution 454/2012, the Canadian Council of the Ministry of Environment and the reference values. The Itupararanga reservoir presented concentrations below Cu, Ni, Pb and Zn and value above the TEL (Threshold Effect Level) for Cr, while the Rio Grande reservoir presented values above the PEL (Probable Effect Level) for Cu and for Pb. The reservoirs had their heterogeneity confirmed with the PCA (Principal Component Analysis), with direct action of the Cu concentration and the lethality, mainly from the points of the Rio Grande reservoir, RG 4 and RG 9. The results showed that the Rio Grande reservoir showed toxicity index much above the PEL, mainly in relation to Cu, causing lethality of the larvae of Chironomus sancticaroli, which highlights the need for monitoring of the reservoirs.

Alquilbenzeno Linear Sulfonado (LAS) é o surfactante aniônico mais utilizado no mundo e é encontrado constantemente em esgoto doméstico e águas residuárias de lavanderia. A remoção de LAS em reatores foi comprovada em estudos anteriores, mas pouco se sabe sobre a toxicidade desse composto em amostras mais complexas para a biota aquática. Neste trabalho, objetivou-se avaliar duas Hipóteses; A: O LAS padrão causa efeitos negativos na biota aquática, e B: O tratamento em reator de leito fluidificado de amostra complexa contendo LAS (água residuária de lavanderia comercial combinada com esgoto doméstico bruto) diminui os efeitos negativos na biota aquática. Ambas as hipóteses foram avaliadas por meio de bioensaios de toxicidade com: Chironomus sancticaroli, Allonais inaequalis e Daphnia magna, analisados a partir da mortalidade dos organismos e análises estatísticas, para determinar os efeitos tóxicos dos LAS padrão e das amostras do reator, comparados ao controle. Para avaliar a Hipótese A foram realizados testes de toxicidade aguda, crônica e crônica de gerações com o LAS padrão. No teste de toxicidade crônica de gerações, com a espécie C. sancticaroli, foram analisados a deformidade bucal, comprimento das larvas, tamanho das asas das fêmeas e fecundidade potencial com o LAS padrão em 3 gerações. Para responder a Hipótese B, foram realizados bioensaios de toxicidade aguda e crônica com os afluentes, efluentes e diluições dos efluentes nas seis fases de operação do reator. C. sancticaroli foi a espécie mais tolerante tanto em teste de toxicidade aguda como crônica com LAS padrão (CL50-96h 25,25 mg.L-1 e CL50-10dias 18,11 mg.L-1), seguido de A. inaequalis (CL50-96h 8,13 mg.L-1 e CL50-10dias 8,56 mg.L-1). A espécie mais sensível ao LAS foi D. magna (CE50-48h 6,11mg.L-1 e CE50-21dias 3,21 mg.L-1). No teste de toxicidade crônica de longa duração, não existiu diferença estatística entre as gerações para o desenvolvimento das larvas do inseto C. sancticaroli, entretanto evidenciaram diferença estatística entre as gerações quanto ao tamanho das asas das fêmeas, indicando que esses organismos podem sofrer alterações fisiológicas quando a exposição ao contaminante é contínua, confirmando a Hipótese A. Os resultados ecotoxicológicos com o reator evidenciaram toxicidade de 100% de todos afluentes e efluentes para A. inaequalis e D. magna. Já C. sancticaroli apresentou menor toxicidade nas primeiras fases de operação (de 20 a 100% de mortalidade). Em geral, foi identificado diferença de toxicidade das fases do reator por meio das diluições. Nas fases menos tóxicas, a diminuição da mortalidade era observada a partir de diluição de 50%; nas fases mais tóxicas, a partir de 20%. É possível concluir que a Fase VIb de operação do reator apresentou diminuição da toxicidade. Entretanto, ao se analisar testes de toxicidade crônica nessa fase, conclui-se que o efluente mesmo depois do tratamento em reator causa efeito negativo nos organismos-teste avaliados, dessa forma é possível refutar a Hipótese B. A partir dos resultados apresentados, é possível concluir que o LAS causa impacto ambiental, principalmente em exposição continua, e que mesmo com remoção em sistema biológico de efluentes reais (água residuária de lavanderia comercial combinada com esgoto doméstico) existe impacto, possivelmente com a interação entre os diversos compostos tóxicos e o LAS. Linear Alkylbenzene Sulfonate (LAS) is the most commonly utilized anionic surfactant in the world and it is present in domestic sewage and laundry wastewater. Removal of LAS in reactors has been proven in previous studies, but little is known about the toxicity to the aquatic biota. The objectives of this study were tested into two Hypotheses, A: The standard surfactant LAS causes negative effects on aquatic biota, and B: Treatment in complex sample fluidized bed reactor containing LAS (commercial laundry wastewater combined with raw domestic sewage) diminishes the negative effects on aquatic biota. Both Hypotheses were evaluated toxicity bioassays using three test organisms: Chironomus sancticaroli, Allonais inaequalis and Daphnia magna. To evaluate the Hypothesis A, acute, chronic and long-term chronic toxicity tests were performed with standard LAS. In the long-term chronic tests with C. sancticaroli organisms, we analyzed the oral deformity, larval length, female wing size and potential fecundity in contact with the standard LAS in 3 generations. Acute and chronic bioassays with affluents, effluents and effluent dilutions in the VI operating phases of the fluidized bed reactor were proceeded to evaluate the Hypothesis B. The results were analyzed from the mortality of the organisms, and statistical analysis were performed to determine the similarity of the toxic effects of the LAS and reactor samples, compared to the control. The species C. sancticaroli was the most tolerant species in both acute and chronic trials with standard LAS (LC50-96h 25.25 mg.L-1 and LC50- 10 days 18.11 mg.L-1), followed by species of A. inaequalis (LC50-96h 8.13 mg.L-1 and LC50-10 days 8.56 mg.L-1). The species most sensitive to LAS was D. magna (CE50-48h 6.11mg.L-1 and CE50-21dias 3.21mg.L-1). In the long-term chronic test, there is no statistical difference between the generations for the development of C. sancticaroli insect larvae. However, they showed a statistical difference between the generations regarding the size of the female wings, indicating that these organisms may undergo physiological changes when exposure to the contaminant is continuous. From these results it is possible to confirm Hypothesis A. The ecotoxicological results with the reactor showed toxicity of 100% of all tributaries and effluents for A. inaequalis and D. magna. The C. sancticaroli species had low toxicity in the first stages of operation (from 20 to 100% mortality). In general, toxicity difference of the reactor phases was identified by half of the dilution analysis. In the less toxic phases, the decrease in mortality was observed from 50% dilution; in the most toxic phases, from 20%. It is also possible to conclude that Phase VIb showed a decrease in the mortality of the test organisms where a chronic test was performed. However, when analyzing the chronic tests, it can be concluded that the effluent even after the treatment in the reactor causes a negative effect on the test organisms evaluated, so it is possible to refute the Hypothesis B. From the results presented, it is possible to conclude that the LAS causes environmental impact, mainly in continuous exposure, and that even with treatment of actual effluents (commercial laundry wastewater combined with domestic sewage) there is an impact, possibly with the interaction between the various toxic compounds and the LAS.

This paper presents a new ecotoxicological test to investigate the response of a Brazilian endemic insect Chironomus sancticaroli through its life cycle and its future generations. This test can evaluate differences between the endpoints analyzed in diverse generations, describing the long-term impact of a substance or matrix effects along the time of exposure. Despite earlier papers already present the generation test with Chironomus riparius, there are still no studies with long-term test applied to C. sancticaroli. In this sense, this study evaluated different conditions for the development of a methodology that prolonged the duration of the test and allowed the best sampling of the organism on environmental toxicity tests. The distinct conditions tested were: volumes of test solution, frequency of feed, number of larvae, type of vessel and test solution replacement. The best condition for the C. sancticaroli generation test includes the exposition of 20 larvae to 340 or 500 mL of test solution, 60 g formulated sediment, feeding with Tetramin® each 10 days and, from a spawn, a new test will be prepared with the same characteristics of the previous one. This new methodology can reveal toxic effects along the exposure time and brings advances on toxicology area. • Prolonged testing makes it possible to analyze the long-term effects • The methodology ''C. sancticaroli generation test'' allows to evaluate the responses of organisms in different life cycles • The methodology allows to analyze the effects of substances in liquid medium and environmental quality through exposure to sediment Method name: Chironomus sancticaroli generation test, Keywords: Chironomus xanthus, Long-term ecotoxicological tests, Life cycle

Made available in DSpace on 2018-12-11T16:51:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-04-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The Cantareira Complex is one of the most important water supplies of the metropolitan region of São Paulo, Brazil. Previously, it was demonstrated that the sediments in this complex were polluted with metals and that Paiva Castro Reservoir—the last reservoir in the sequence, which receives water from the five previous reservoirs—was the reservoir with the greatest concentration of pollutants. Based on field data, it was noticed that copper concentrations in sediments were related to morphological alterations in chironomids. The present study provides novel monitoring methods and results for the complex by isolating the environmental and biological sources of variation. An adaptation of the in situ assay proposed by Soares et al. (Arch Environ Contam Toxicol 49:163–172, 2005), which uses a native tropical Chironomus species and low-cost materials, is also provided. The aim of this study was to isolate the effects of sediments from Paiva Castro on controlled populations of C. sancticaroli larvae using an in situ assay. A seven-day experiment was performed in triplicate. Third instar larvae were inoculated in chambers containing sediments from two distinct regions of Paiva Castro reservoir and a control site with sand. Five biological responses were considered: mouthpart alterations, larval length, width of cephalic capsule, mortality and total damage. The results suggest the effects of sediment toxicity on larvae include a reduction in length and a higher occurrence of total damage. Programa de Pós-Graduação em Ciências Ambientais - Instituto de Ciência e Tecnologia de Sorocaba UNESP, Avenida Três de Março, 511 – Alto da Boa Vista Departamento de Ecologia – Instituto de Biociências Universidade de São Paulo, Rua do Matão, 321, travessa 14 – Cidade Universitária Catalan Institute for Water Research (ICRA) Carrer Emili Grahit 101 Programa de Pós-Graduação em Ciências Ambientais - Instituto de Ciência e Tecnologia de Sorocaba UNESP, Avenida Três de Março, 511 – Alto da Boa Vista FAPESP: 2012/11890-4 FAPESP: 2012/16420-6 FAPESP: 2013/03494-4 FAPESP: 2013/08272-0 FAPESP: 2014/22581-8

Determining the age composition of a population is important when conducting ecological, taxonomic and environmental assessments. Morphometric measurements of the head capsule, especially the length and width, are widely used in the identification of insect instars, but alternative ways for determining the age of insects can expand the options for the analysis of field and laboratory populations. This study evaluated the morphometry of the antennae, mandibles, mentum and ventromental plates to discriminate among the four larval instars of Chironomus sancticaroli Strixino & Strixino, 1981. The larvae were reared in the laboratory under constant temperature (25°C) and photoperiod of 12/12 hours for 19 days, with a supply of food. Fifteen larvae were removed randomly every day, cleared in KOH, and slide-mounted, and had the antennae, mandibles, mentum and ventromental plates measured. The dimensions of the four structures studied allowed us to statistically distinguish each of the four larval instars. The data fit an exponential equation according to the Brooks-Dyar rule, which allows an estimate of the larval instar of specimens collected in the field, even when development takes place under different conditions. The duration of each instar was also obtained from our data, and showed an overlap of instars during development.