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Aquatic worms are considered a suitable group to evaluate the effects of contaminants in the environment, although one of the main challenges is using native species. Recently, Pristina longiseta was suggested to be used in acute bioassays for tropical regions. In this context, the aim of this study was to establish a chronic exposure for ecotoxicological bioassays utilizing the tropical native species P. longiseta. Firstly, we tested three exposure times (96h, 7d, and 10d) in the presence and absence of aeration. After determining the best configuration, we evaluated the effects of the chronic exposures using the standardized reference substance potassium chloride, the antibiotic sulfamethoxazole, the flame retardant tetrabromobisphenol-A, and sugarcane vinasse. Our results showed the suitability for applying the chronic exposure using P. longiseta and indicated the sensitivity of the offspring to KCl (EC50 = 0.51 g/L). Sulfamethoxazole and TBBPA caused a significant reduction in the offspring of P. longiseta (EC50 = 59.9 µg/L and 166.1 µg/L, respectively). Sugarcane vinasse showed high toxicity for the species, and a fraction of 4.26% of vinasse was calculated as EC50. Therefore, the described protocol was successfully applied as an ecotoxicological assessment to evaluate the effects of contaminants on the reproduction rate of the freshwater worm P. longiseta.

Using Pyriproxyfen to control Aedes aegypti populations shows great potential considering its high competence in low dosages and environmental safety. As an endocrine disruptor, temperature can interfere in its efficiency, related to a decrease in larval emergence inhibition in hotter environments. However, previous studies have been performed at constant temperatures in the laboratory, which may not precisely reflect the environmental conditions in the field. This study aimed to assess the effect of the fluctuating temperatures in pyriproxyfen efficiency on controlling Aedes aegypti larvae. We selected maximum and minimum temperatures from the Brazilian Meteorological Institute database from September to April for cities grouped by five regions. Five fluctuating temperatures (17–26; 20–28.5; 23–32.5; 23–30.5; 19.5–31 ºC) were applied to bioassays assessing Pyriproxyfen efficiency in preventing adult emergence in Aedes aegypti larvae in five concentrations. The proportion of emergence inhibition was compared among treatments and within treatment. In thermal conditions with the lowest temperatures, Pyriproxyfen was efficient to prevent the emergence of twice the larvae than in the hottest temperatures with the lowest concentration applied (average ± SD: 0.61 ± 0.09 in coldest treatment; average ± SD: 0.65 ± 0.12 in the hottest treatment, p value = 0.00015). The concentration that inhibits the emergence of 50% of the population was lower than that preconized by the World Health Organization (0.01 mg/L) in all treatments, except for the hottest temperatures, for which we estimated 0.010 mg/L (SD ± 0.017). Applying fluctuating temperatures in laboratory bioassays provides a more realistic result for vector surveillance strategies. For a country with continental proportions such as Brazil, considering regionalities is crucial for a rational use of insecticides.

For different research purposes, there is a need to mass rear mosquitoes, such as Aedes aegypti, under laboratory conditions. The rearing process begins with egg production followed by egg storage in a dry environment, inside containers. Stored eggs are susceptible to environmental threats when storage conditions are suboptimal. Some terrestrial insects can invade this environment and attack stored eggs. In this brief report, we assessed whether Ae. aegypti eggs exposed to Liposcelis sp. individuals had reduced hatching and immature development rates. We exposed 100 eggs in different treatment conditions (fixed in porous paper and loosed) to 30 Liposcelis sp. individuals for ten days and then we induced hatching. We observed a hatching rate of 99% reduced for those eggs adhered to porous paper and loosed eggs showed a hatching rate of 45% decreased for those eggs exposed to Liposcelis sp. The remaining larvae took longer to develop into pupae as well, showing a four-day delay on average to the final metamorphosis of the aquatic stage. These results reinforce the need to frequently monitor egg storage conditions to maintain laboratory colonies stable and free from pests that can interfere with mosquito life-history traits.

This paper includes a systematic review of the SARS-CoV-2 occurrence in environmental aquatic matrices and a critical sanitation analysis. We discussed the interconnection of sanitation services (wastewater, water supply, solid waste, and stormwater drainage) functioning as an important network for controlling the spread of SARS-CoV-2 in waters. We collected 98 studies containing data of the SARS-CoV-2 occurrence in aquatic matrices around the world, of which 40% were from developing countries. Alongside a significant number of people infected by the virus, developing countries face socioeconomic deficiencies and insufficient public investment in infrastructure. Therefore, our study focused on highlighting solutions to provide sanitation in developing countries, considering the virus control in waters by disinfection techniques and sanitary measures, including alternatives for the vulnerable communities. The need for multilateral efforts to improve the universal coverage of sanitation services demands urgent attention in a pandemic scenario.

Soil toxicity tests are commonly applied using Enchytraeus crypticus to analyze reproductive outputs. However, the traditional method for counting potworms takes a long time due to the significant number of offspring. This paper compares the conventional total counting of E. crypticus juveniles (M1) and an alternative methodology (M2). The proposed methodology (M2) uses a simple random counting method (1/4) for the partial counting of juveniles and total estimation. Chronic bioassays (21 days of exposure) were performed in tropical artificial soil (TAS) using sugarcane vinasse as a hazardous substance. Comparing the final density of juveniles recorded in M1 and M2, no statistical differences were pointed out in either one. Applying analyses based on effective concentration (EC10 and EC50), no statistical differences were identified there either. The t-test showed that there was no statistical difference between the counting methods (M1 and M2) in each treatment (control and dilutions). Moreover, we ran the Tukey test for M1 and M2 methods separately and observed that 100 % of the vinasse showed a statistical difference compared to the control treatment in both (p ≤ 0.05), affirming that independent of the counting method, the ecotoxicological outputs were similar. Therefore, the proposed alternative is a suitable method for bioassay using. E. crypticus in tropical artificial soil, decreasing to 1/4 the total time required for counting.

The use of ecotoxicological bioassays has been increasing due to the importance of understanding the effects of substances on biota and to help environmental agencies determine water and sediment qualities. The use of Chironomus sp. in laboratory bioassays is extensive, but there is still a lack of studies regarding the application of extended ecotoxicological tests, which evaluate different population generation responses and show a detailed impact on their development. The present study investigated the response of Chironomus sancticaroli, a Brazilian endemic insect, to 17α-ethinylestradiol hormone, caffeine anhydrous, LAS (linear alkylbenzene sulfonate), and environmental samples (sediments) in relation to wing length, fecundity, and larval length over three generations. Statistically, differences for all contaminants between P (parental), F1, and F2 generations (p ≤ 0.05) were observed, indicating that in the environment, the organism may be negatively affected when exposed to contaminants in successive generations. Different ecological responses were also noted in comparison to classic acute (96h) and chronic (10 days) ecotoxicological tests using Chironomus sancticaroli. Our results highlight that the generation test can present more detailed results regarding the effects of stressors on the organism's life cycle than do the classic bioassays.

Several studies have assessed the efficiency of insect growth regulators to control Aedes aegypti under laboratory conditions. However, empirical evidence evaluating how insect growth regulators respond to different temperatures is scarce. In this paper, we evaluate whether temperature may influence the efficiency of pyriproxyfen. To do so, we analyzed the effect of three temperatures (20, 25 and 30 °C) combined with five pyriproxyfen concentrations (0.0001, 0.001, 0.01, 0.1 and 1 mg L−1) on Ae. aegypti larval control. Each experiment had five replicates containing 250 mL of the test solution and 20 larvae according to WHO protocol. Tests were conducted until all mosquitoes had either fully emerged from the control beakers or died. The outcomes showed that, as we increased the temperature, not only did the larval developmental time decrease (from 23.5 to 10.7 days) but also the concentration of larvicide required for 50% (EC50 of 0.0002 and 0.0050 mg L−1 for 20 and 30 °C, respectively) and 95% efficiency increased (EC50 of 0.009 and 0.013 mg L−1 for 20 and 30 °C, respectively). We highlight how temperature changes produce different results from larvicide applications (p

Secondary production estimates are an important element of ecosystem ecology because they facilitate quantification of the roles of consumers in material and energy cycling. We estimated pr...

An accurate and sensitive ultrasound-dispersive liquid-liquid microextraction technique followed by high-performance liquid chromatography separation coupled with electrospray ionization tandem mass spectrometry detection method to determine the presence of tetrabromobisphenol A (TBBPA) in complex environmental matrices is proposed. The miniaturized procedure was used to extract and quantify the analyte in domestic sewage, anaerobic sludge, and the aquatic test organism species Daphnia magna and Chironomus sancticaroli, which are standardized organisms for ecotoxicity bioassays. Limits of detection of 2 ng L-1 (domestic sewage), 2 ng g-1 (anaerobic sludge), 0.25 ng g-1 (D. magna), and 5 ng g-1 (C. tentans) were obtained. The presence of TBBPA was determined in domestic sewage and anaerobic sludge from an anaerobic batch bioreactor at a concentration of 0.2 ± 0.03 μg L-1 and 507 ± 79 ng g-1 , respectively. In D. magna and C. sancticaroli exposed to TBBPA in an acute toxicity bioassay, the micropollutant accumulated at 3.74 and 8.87 μg g-1 , respectively. The proposed method is a simple and cost-effective tool to determine TBBPA environmental occurrence and biomagnification potential compared with conventional extraction methods. To the best of our knowledge, this is the first liquid-liquid miniaturized extraction method to be applied to D. magna and C. sancticaroli. Environ Toxicol Chem 2020;39:2147-2157. © 2020 SETAC.

Aedes aegypti control in Brazil comprises integrated actions, in which larvicide application is a supplementary measure. Despite the importance of analyzing the effects of temperature on the efficiency of larvicides to control mosquito populations, there is still a lack of information regarding the sublethal effect of larvicides. We hypothesized that mosquitoes which survived pyriproxyfen exposure, during their immature development, have small body sizes and live less than mosquitoes that were not exposed to this larvicide. We investigated the sublethal effects of five different pyriproxyfen concentrations (0.0001; 0.001; 0.01; 0.1 and 1 mg.L−1), under three different temperatures (20, 25 and 30 °C). As we increased the larvicide concentration, less larvae survived and developed into adults. However, at 30 °C the survival was higher than at 25 °C and 20 °C comparing the concentrations of 0.001 mg.L−1 and 0.01 mg.L−1 (10% and 16% high, respectively). Mosquito survivors to pyriproxyfen exposure, in all thermal conditions, had shorter adult life spans than mosquitoes not exposed to pyriproxyfen during the larval stage. The females exposed at 30 °C showed smaller wings than females from experiments at 20 °C. These findings provide evidence that the biological parameters of the adult lifespan and wing centroid size are impaired due to larval exposure to pyriproxyfen, even at high temperatures. Reduced longevity and small wing size are fitness costs to survive this larvicide exposure. These findings provide support to assess resistance development to larvicides through future generations and contribute to the discussion on improving the rational application of larvicides.

The knowledge about the diversity and fauna distribution in tropical freshwater ecosystems is of extreme ecological importance, however studies on this theme still scarce. Organisms belonging to the Oligochaeta Class are considered important bioindicators for environmental quality analysis, but detailed knowledge about these organisms is still insufficient. This study aims to investigate the occurrence of oligochaeta species in eight rivers of the State of São Paulo (Brazil), to expand the species catalogue and identify the its relationship with the trophic state of sampled environments. The samples were collected by the Environmental Company of the State of São Paulo (CETESB) from 2014 to 2016 and include areas with different land uses, ranging from conservation, agricultural and industrial. We used species richness estimator (Bootstrap) and accumulation curves of randomized species (collector curve), in order to evaluate the efficiency of samples collected. Rivers were classified according to the trophic state, ranging from oligotrophic to hypereutrophic. As a result, we identified a total of 7,398 oligochaetes distributed in 25 taxa, which belong to the families: Alluroididae, Naididae and Opistocystidae. The most frequent species registered in this research, present in seven of the eight sampled rivers was Bothrioneurum sp., followed by Pristina synclites registered in six of the eight sampled rivers. O conhecimento da diversidade e distribuição da fauna em ecossistemas tropicais de água doce é de extrema importância ecológica, contudo estudos sobre essa temática ainda são escassos. Organismos pertencentes à Classe Oligochaeta são considerados bioindicadores importantes para análise da qualidade ambiental em ecossistemas aquáticos, porém o conhecimento detalhado sobre esses organismos é insuficiente. Este estudo teve como objetivo promover uma lista de ocorrência de espécies Oligochaeta em oito rios do Estado de São Paulo (Brasil), com o intuito de ampliar o catálogo de espécies e identificar sua relação com o estado trófico dos ambientes amostrados. As amostras foram coletadas pela Companhia Ambiental do Estado de São Paulo (CETESB) no período de 2014 a 2016 e incluem áreas com diferentes usos do solo, variando entre áreas de conservação, agropecuária e industrial. Para avaliar a eficiência das amostras coletadas nos rios foi utilizado o estimador de riqueza de espécies (Bootstrap) e curvas de acumulação de espécies randomizadas (curva do coletor). Os rios foram classificados de acordo com seu estado trófico variando de oligrotrófico à hipereutrófico. Como resultado, identificamos um total de 7.398 oligoquetos distribuídos em 25 táxons, os quais pertencem às famílias: Alluroididae, Naididae e Opistocystidae. A espécie mais frequente registrada nesta pesquisa, presente em sete dos oito rios amostrados foi Bothrioneurum sp., seguida de Pristina synclites registrada em seis dos oito rios amostrados.

Made available in DSpace on 2022-04-29T08:38:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Metals can be incorporated into stream sediment affecting benthic invertebrate assemblages in different ways. Odonata larvae have variable tolerances to metals; sublethal levels accumulated in larval tissue can indirectly influence assemblage structure in environments with differences in types and concentrations of metals in the sediment. This research evaluated the relationship between Odonata larvae assemblages and sediment metal content in Cerrado streams. We evaluated genus composition, abundance, richness, Shannon-Wiener (H’) diversity index and Pielou’s evenness index (J’) of the assemblages from 12 streams. Cluster analysis was used to identify groups of streams according to sediment concentrations of Cu (copper), Zn (zinc), Ni (nickel), Fe (iron) and Mn (manganese). Canonical Redundancy Analysis (RDA) and Canonical Correspondence Analysis (CCA) were performed to determine how metals influence Odonata assemblage metrics. Cluster analysis revealed three distinct groups of streams according to metal concentration in the sediment. RDA showed a negative relation between Pielou evenness (J’) and the concentration of Ni, Cu, Zn and Mn, while abundance, genus richness and Shannon-Wiener diversity were positively related with Fe. CCA indicated that some taxa showed an opposite relation with metal concentration, but others were more abundant in streams subjected to high metal concentrations. Although the increase in iron concentration in streams can lead to an increase in the abundance of Odonata larvae, high concentrations of coper, zinc and manganese can lead to a reduction in taxon evenness. Instituto Estadual de Florestas, Praça Tubal Vilela, Minas Gerais Programa de Pós-Graduação em Ecologia e Evolução Instituto de Ciências Biológicas Universidade Federal de Goiás, Av. Esperança, Campus Samambaia, Goiás Instituto de Química Departamento de Química Analítica Universidade Estadual Paulista Júlio de Mesquita Filho, Rua Prof. Francisco Degni, São Paulo Instituto de Ciências Exatas e Naturais do Pontal Universidade Federal de Uberlândia, Rua 20, 1600, Minas Gerais Escola de Engenharia de São Carlos Universidade de São Paulo, Av. Trabalhador Sancarlense, São Paulo Instituto de Biologia Universidade Federal de Uberlândia, Rua Ceará, Minas Gerais Instituto de Química Departamento de Química Analítica Universidade Estadual Paulista Júlio de Mesquita Filho, Rua Prof. Francisco Degni, São Paulo

Prefácio Dossiê

The aim of this paper was recording the occurrence of the species Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) in lotic systems of the State of São Paulo. Specimens were collected in Sapucaí River, located in Campos do Jordão State Park. The mapping of geographical distribution of this species is of interest to public health since L. variegatus may be an intermediate host of Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), a parasite of recognized zoonotic potential. Distribution data serves as a basis for environmental monitoring and evaluation, being essential to map possible cases of the disease (Dioctophimosis) and provide information to health professionals.

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.

Slow sand filtration is a common technology providing potable water in rural households across Latin America, Asia and Africa. Two PVC household slow sand filters (HSSF) were operated in continuous (C-HSSF) and intermittent (I-HSSF) flow modes for eight consecutive months. A non-woven blanket was installed on the fine sand top to facilitate cleaning with scheduled maintenance undertaken every 30 days. The efficiency of each HSSF was evaluated via physico-chemical indicators (reduction of turbidity and colour) with biological performance assessed via total coliform and

This study evaluated the ecotoxicity effects of effluent from an anaerobic fixed bed biofilm reactor (AFBBR) removing the sulfamethoxazole (SMX - 403 ± 104 ng L−1) and ciprofloxacin (CIP - 294 ± 123 ng L−1) antibiotics from domestic sewage in some microorganisms (Brevundimonas sp., Escherichia coli, Ochrobactrum sp., Sphingomonas sp.) and benthic organisms (Allonais inaequalis and Chironomus sancticaroli). The AFBBR showed high removal efficiency of SMX (85 ± 10%) and CIP (81 ± 16%) and completely eliminated the acute ecotoxicological effect on the C. sancticaroli insect larvae. The bioreactor effluent did not cause any inhibition on the cell growth of the microorganisms. Nonetheless, the A. inaequalis was extremely sensitive to the reactor effluent (100% mortality), probably due to the death of bacteria and algae essential to the nutrition of the Oligochaeta. Regarding the adult insect emergency of C. sancticaroli, a reduction of 50% was observed after 17 days of exposure to the effluent with 40 μgSMX L−1, inhibiting the larval development, which did not occur for CIP. The antimicrobial inhibition by CIP present in the domestic sewage resulted in EC50 (median effective concentration) values of 2.5, 0.9, 3.1 and 0.1 mgCIP L−1 for Ochrobactrum sp., Brevundimonas sp., Sphingomonas sp. and E. coli, respectively. Assessing the effect of antibiotics in the effluent on the microorganisms’ growth by a disk diffusion test, only E. coli culture showed inhibition at the concentration of 5.0 mgCIP L−1. The study emphasized the potential of AFBBR to reduce ecotoxicity in the sewage on aquatic biota.

This work sought the survey of species and information about the distribution of the Class Oligochaeta in reservoirs sampled in the Sediment Quality Monitoring Network of CETESB (Environmental Company of the State of São Paulo). As such, this study aimed to inventory the limnic oligochaetes fauna to expand knowledge of the ecology and distribution of this group in reservoirs in the state of São Paulo. Ninety replicates were performed in 12 reservoirs in the state of São Paulo between 2014 and 2016, using van Veen or Ponar samplers in the sublittoral region, and Ekman-Birge in the deep region. Twenty-eight taxa were inventoried, belonging to the families Naididae and Opistocystidae. The species Dero righii and Pristina longisoma were recorded for the first time in São Paulo State, Nais magnaseta and Spirosperma velutina were first recorded in Brazil. The results presented here make this inventory extremely important for understanding the distribution of aquatic oligochaetes throughout the Brazilian territory. Resumo: Este trabalho buscou o levantamento de espécies e informações sobre a distribuição da Classe Oligochaeta em reservatórios amostrados na Rede de Monitoramento da Qualidade de Sedimentos da CETESB (Companhia Ambiental do Estado de São Paulo). Sendo assim, este estudo objetivou inventariar a fauna de oligoquetos para expandir o conhecimento de ecologia e distribuição deste grupo em reservatórios no Estado de São Paulo. Foram realizadas 90 réplicas em 12 reservatórios no estado de São Paulo entre os anos de 2014 a 2016, utilizando amostradores van Veen ou Ponar na região sublitoral, e Ekman-Birge na região profunda. Foram inventariados 28 táxons, pertencentes às famílias Naididae e Opistocystidae. As espécies Dero righii e Pristina longisoma, foram registradas pela primeira vez no Estado de São Paulo, Nais magnaseta e Spirosperma velutina foram identificadas pela primeira vez no Brasil. Os resultados apresentados aqui tornam este inventário de suma importância para o conhecimento da distribuição dos oligoquetos aquáticos em todo o território brasileiro.

As a consequence of accelerated and excessive use of pesticides in tropical regions, wilderness areas are under threat; this includes the Pantanal wetlands in the Upper Paraguay River Basin (UPRB). Using a Land Cover Land Use Change (LCLUC) modelling approach, we estimated the expected pesticide load in the Pantanal and the surrounding highlands region for 2050 under three potential scenarios: i) business as usual (BAU), ii) acceleration of anthropogenic changes (ACC), and iii) use of buffer zones around protected areas (BPA). The quantity of pesticides used in the UPRB is predicted to vary depending on the scenario, from an overall increase by as much as 7.4% in the UPRB in the BAU scenario (increasing by 38.5% in the floodplain and 6.6% in the highlands), to an increase of 11.2% in the UPRB (over current use) under the AAC scenario (increasing by 53.8% in the floodplain and 7.5% in the highlands). Much higher usage of pesticides is predicted in sub-basins with greater agricultural areas within major hydrographic basins. Changing the current trajectory of land management in the UPRB is a complex challenge. It will require a substantial shift from current practices, and will involve the implementation of a number of strategies, ranging from the development of new technologies to achieve changes in land use policies, to increasing dialogue between farmers, ranchers, the scientific community, and local or traditional communities through participatory learning processes and outreach.