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This study introduces an innovative approach for quantifying isomeric pollutants utilizing an amperometric sensor. The determination of the isomers hydroquinone and catechol is based on the use of a glassy carbon electrode modified with Cu@PtPd/C nanoparticles (Cu@PtPd/C/GCE) in core-shell form, showing significant electrocatalytic activity in the oxidation of the later compounds. The determination was carried out at two different potentials: one at which where only hydroquinone is oxidized, and another in which where both hydroquinone and catechol are oxidized. Using these potentials, two calibration curves were built, one for the quantification of hydroquinone and the other for both isomers. Subsequently, the quantification of catechol was performed using a strategy based on the calculation of a difference using the information collected in the first step. The experiments using hydrogen peroxide as a redox probe demonstrate a clear synergistic effect in the catalytic reduction of hydrogen peroxide at -0.100 V, when Pt, Pd and Cu are incorporated into the core-shell nanostructure. The best performance was achieved with Cu@PtPd/C/GCE 1.00 mg mL-1. For the selected sensor, the analytical parameters are very competitive compared to similar devices reported in recent years for hydroquinone and catechol, with comparable linearity ranges of 0.010-0.200 mmol L-1 (hydroquinone) and 0.005-0.500 mmol L-1 (catechol), low limits of detection (LODs) of 14.0 nmol L-1 (S/N = 3.3) and 1.75 nmol L-1 (S/N = 3.3) for hydroquinone and catechol. The resulting sensor platform has been successfully applied for the quantification of hydroquinone and catechol in river and tap water and could be a promising candidate for environmental monitoring and drinking water safety.

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The application of innovative systems using low-cost microcontrollers in human biometeorology studies is a promising alternative to conventional monitoring devices, which are usually cost-intensive and provide measurements at specific points, as in stationary meteorological stations. A Portable Low-cost Environmental Monitoring System (PLEMS) aimed at the pedestrian scale is introduced. The backpack-type equipment consists of a microcontroller with attached sensors that assess environmental conditions in a broad sense, integrating measurements of air quality, lighting and noise levels alongside variables typically measured at meteorological stations. The application of the system took place in altogether 12 environmental walks carried out with questionnaire-surveys with concurrent environmental monitoring with the PLEMS in Curitiba, Brazil, a subtropical location characterized by a Cfb climate type. Results allowed us to test the equipment and method of data gathering within a limited period (approximately 50 min) and for a short walking circuit of 800 m. The equipment was successfully able to capture even slightest differences in environmental conditions among points of interest, whereas subjective responses (n= 3843 responses to a total of 11 questions) showed consistency with measured data. From a multi-domain perspective, relevant insights could be obtained for the measured variables.

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The intensive global use of pesticides presents an escalating threat to human health, ecosystems, and water quality. To develop national and local environmental management strategies for mitigating pollution caused by pesticides, it is essential to understand the quantities, timing, and location of their application. This study aims to estimate the spatial distribution of pesticide use in an agricultural region of La Plata River basin in Uruguay. Estimates of pesticide use were made by surveying doses applied to each crop. This information was spatialized through identifying agricultural rotations using remote sensing techniques. The study identified the 60 major agricultural rotations in the region and mapped the use and application amount of the nine most significant active ingredients (glyphosate, 2,4-dichlorophenoxyacetic acid, flumioxazin, S-metolachlor, clethodim, flumetsulam, triflumuron, chlorantraniliprole, and fipronil). The results reveal that glyphosate is the most extensively used pesticide (53.5% of the area) and highest amount of use (> 1.44 kg/ha). Moreover, in 19% of the area, at least seven active ingredients are applied in crop rotations. This study marks the initial step in identifying rotations and estimating pesticide applications with high spatial resolution at a regional scale in agricultural regions of La Plata River basin. The results improve the understanding of pesticide spatial distribution based on data obtained from agronomists, technicians, and producers and provide a replicable methodological approach for other geographic and productive contexts. Generating baseline information is key to environmental management and decision making, towards the design of more robust monitoring systems and human exposure assessment.

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Mercury is a naturally occurring metal found in various inorganic and organic forms within the environment. Due to its high toxicity, there is global concern regarding human exposure to this element. The combination of high-performance liquid chromatography and inductively coupled plasma mass spectrometry (HPLC-ICP-MS) is commonly used to analyze the different forms of mercury in a sample due to its high sensitivity and ability to selectively detect mercury. However, the traditional HPLC-ICP-MS methods are often criticized for their lengthy analysis times. In this study, we have refined the conventional approach by transitioning to ultra-high performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (UHPLC-ICP-MS). This modification has resulted in significant reductions in runtime as well as reagent and argon usage, thereby offering a more rapid, environmentally friendly, and cost-effective method. We successfully adapted an HPLC-ICP-MS method to UHPLC-ICP-MS, achieving the analysis of Hg2+ and MeHg+ within 1 min with a mobile phase consumption of only 0.5 mL and a sample volume of 5.0 µL; this is a major advance compared to HPLC analysis with run times generally between 5 and 10 min. The method's performance was assessed by analyzing muscle and liver tissue samples (serving as reference material) from fish, demonstrating the versatility of the method in relation to different complex matrices.

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RESUMEN El hormiguero palmero Myrmecophaga tridactyla es una especie que se encuentra amenazada en la Orinoquía, por la fragmentación del paisaje, el atropellamiento en las vías, los monocultivos de arroz, la palma africana y la actividad de extracción de petróleo. El atropellamiento de animales en las redes viales disminuye la tasa de supervivencia anual de los hormigueros, reduciendo la tasa de crecimiento de la especie a valores nulos, como se observa en algunas áreas. Por otro lado, los animales enfermos o atropellados requieren diagnóstico o tratamiento para recuperar su salud, por lo tanto, el propósito del trabajo fue conocer la hematología y la bioquímica sérica en animales silvestres, aparentemente sanos, rescatados por Cormacarena. Previa restricción y sedación con Zoletil® 50, a la dosis de 4 mg/k de peso vivo, se practicó examen clínico y se recolectó de 5-10 mL de sangre por venopunción, a 21 animales. Posterior a su recuperación se liberaron los individuos. Se presentan los valores hematológicos de referencia para eritrocitos, hemoglobina, hematocrito, plaquetas, leucocitos, neutrófilos, linfocitos, proteínas totales, ALT, AST, BUN, creatinina, calcio, fósforo, potasio, sodio, los cuales, son de importancia en la valoración médico-veterinaria, en los programas de conservación de la especie. Se resalta que los valores en osos palmeros de la región son similares a los descritos en otros trabajos en América.

ABSTRACT The giant anteater, Myrmecophaga tridactyla is a species threatened in the Orinoquia region by the fragmentation of the landscape, the running over of the roads, the monocultures of rice, african palm, and the activity of oil extraction. Running over animals on road networks decreases the annual survival rate of giant anteaters from 0.95 to levels of 0.78 reducing the growth rate of the species to null values. On the other hand, sick or run-over animals require diagnosis or treatment to recover their health; in this sense, the work aimed to know the hematology and serum biochemistry in apparently healthy wild animals rescued by Cormacarena. After restriction and sedation with Zoletil ® 50, at a dose of 4 mg/kg of live weight, a clinical examination was performed, and 5-10ml of blood was collected by venipuncture from 21 animals; after recovery, the individuals were released. This work presents the references hematological values of erythrocytes, hemoglobin, hematocrit, platelets, leukocytes, neutrophils, lymphocytes total protein, ALT, AST, BUN, creatinine, calcium, phosphorus, potassium, sodium, which are essential for the veterinary medical assessment for the conservation programs of the species. It is highlighted that the results for palm tree bears in the region are like those described in other works in America.

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Whole-cell biosensors could serve as eco-friendly and cost-effective alternatives for detecting potentially toxic bioavailable heavy metals in aquatic environments. However, they often fail to meet practical requirements due to an insufficient limit of detection (LOD) and high background noise. In this study, we designed a synthetic genetic circuit specifically tailored for detecting ionic mercury, which we applied to environmental samples collected from artisanal gold mining sites in Peru. We developed two distinct versions of the biosensor, each utilizing a different reporter protein: a fluorescent biosensor (Mer-RFP) and a colorimetric biosensor (Mer-Blue). Mer-RFP enabled real-time monitoring of the culture's response to mercury samples using a plate reader, whereas Mer-Blue was analysed for colour accumulation at the endpoint using a specially designed, low-cost camera setup for harvested cell pellets. Both biosensors exhibited negligible baseline expression of their respective reporter proteins and responded specifically to HgBr2 in pure water. Mer-RFP demonstrated a linear detection range from 1 nM to 1 µM, whereas Mer-Blue showed a linear range from 2 nM to 125 nM. Our biosensors successfully detected a high concentration of ionic mercury in the reaction bucket where artisanal miners produce a mercury-gold amalgam. However, they did not detect ionic mercury in the water from active mining ponds, indicating a concentration lower than 3.2 nM Hg2+-a result consistent with chemical analysis quantitation. Furthermore, we discuss the potential of Mer-Blue as a practical and affordable monitoring tool, highlighting its stability, reliance on simple visual colorimetry, and the possibility of sensitivity expansion to organic mercury.

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Payments for ecosystem services (PES) are widely applied incentive-based instruments with diverse objectives that increasingly include biodiversity conservation. Yet, there is a gap in understanding of how to best assess and monitor programs' biodiversity outcomes. We examined perceptions and drivers of engagement related to biodiversity monitoring through surveys among current PES participants in 7 communities in Mexico's Selva Lacandona. We conducted workshops among survey participants that included training and field deployment of tools used to monitor biodiversity and land cover, including visual transects, camera traps, acoustic recorders, and forest cover satellite images. We conducted pre- and postworkshop surveys in each community to evaluate changes in respondents' perceptions following exposure to biodiversity monitoring training and related field activities. We also reviewed existing research on participatory environmental management and monitoring approaches. One quarter of current PES participants in the study area participated in our surveys and workshops. The majority stated interest in engaging in diverse activities related to the procedural aspects of biodiversity monitoring (e.g., planning, field data collection, results dissemination) and acknowledged multiple benefits of introducing biodiversity monitoring into PES (e.g., knowledge and capacity building, improved natural resource management, and greater support for conservation). Household economic reliance on PES was positively associated with willingness to engage in monitoring. Technical expertise, time, and monetary constraints were deterrents. Respondents were most interested in monitoring mammals, birds, and plants and using visual transects, camera traps, and forest cover satellite images. Exposure to monitoring enhanced subsequent interest in monitoring by providing respondents with new insights from their communities related to deforestation and species' abundance and diversity. Respondents identified key strengths and weaknesses of applying different monitoring tools, which suggests that deploying multiple tools simultaneously can increase local engagement and produce complementary findings and data. Overall, our findings support the relevance and usefulness of incorporating participatory biodiversity monitoring into PES.

Explorando las percepciones locales y los impulsores de la participación en el monitoreo de la biodiversidad entre participantes de esquemas de pagos por servicios ambientales en el sureste de México Resumen Los pagos por servicios ambientales (PSA) son instrumentos basados en incentivos ampliamente aplicados cuyos diversos objetivos incluyen cada vez más la conservación de la biodiversidad. Sin embargo, existe una brecha en la comprensión de cómo evaluar y monitorear los resultados de los programas en materia de biodiversidad. Examinamos las percepciones y los impulsores de la participación relacionados al monitoreo de la biodiversidad a través de encuestas entre participantes actuales de PSA en siete comunidades de la Selva Lacandona de México. Realizamos talleres entre los participantes de las encuestas que incluyeron capacitación y despliegue en campo de herramientas utilizadas para monitorear la biodiversidad y la cobertura del suelo, incluidos transectos visuales, cámaras trampa, grabadores acústicos e imágenes satelitales de la cobertura forestal. Realizamos encuestas antes y después del taller en cada comunidad para evaluar los cambios en las percepciones de los participantes tras su involucramiento en la capacitación de monitoreo de biodiversidad y las actividades de campo relacionadas. También revisamos la investigación existente sobre enfoques de monitoreo y gestión ambiental participativa. Una cuarta parte de los participantes actuales de PES en el área de estudio participaron en nuestras encuestas y talleres. La mayoría declaró interés en participar en diversas actividades relacionadas con los aspectos procesales del monitoreo de la biodiversidad (por ejemplo, planificación, recopilación de datos de campo, difusión de resultados) y reconoció múltiples beneficios de introducir el monitoreo de la biodiversidad en los PSA (por ejemplo, creación de conocimientos y capacidades, mejora de la gestión de los recursos naturales, y mayor apoyo a la conservación). La dependencia económica de los hogares de los PSA se asoció positivamente con la voluntad de participar en el monitoreo. Los factores inhibidores fueron la experiencia técnica, el tiempo y las limitaciones monetarias. Los encuestados estaban más interesados en monitorear mamíferos, aves y plantas y en utilizar transectos visuales, cámaras trampa e imágenes satelitales de la cubierta forestal. La exposición al monitoreo aumentó el interés posterior en el monitoreo al brindar a los encuestados nuevos conocimientos de sus comunidades relacionados con la deforestación y la abundancia y diversidad de especies. Los encuestados identificaron fortalezas y debilidades clave al aplicar diferentes herramientas de monitoreo, lo que sugiere que implementar múltiples herramientas simultáneamente puede aumentar la participación local y producir hallazgos y datos complementarios. En general, nuestros hallazgos respaldan la relevancia y utilidad de incorporar el monitoreo participativo de la biodiversidad en los PSA.

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Soil quality monitoring in mining rehabilitation areas is a crucial step to validate the effectiveness of the adopted recovery strategy, especially in critical areas for environmental conservation, such as the Brazilian Amazon. The use of portable X-ray fluorescence (pXRF) spectrometry allows a rapid quantification of several soil chemical elements, with low cost and without residue generation, being an alternative for clean and accurate environmental monitoring. Thus, this work aimed to assess soil quality in mining areas with different stages of environmental rehabilitation based on predictions of soil fertility properties through pXRF along with four machine learning algorithms (projection pursuit regression, PPR; support vector machine, SVM; cubist regression, CR; and random forest, RF) in the Eastern Brazilian Amazon. Sandstone and iron mines in different chronological stages of rehabilitation (initial, intermediate, and advanced) were evaluated, in addition to non-rehabilitated and native forest areas. A total of 81 soil samples (26 from sandstone mine and 55 from iron mine) were analyzed by both traditional wet-chemistry methods and pXRF. The available/exchangeable contents of K, Ca, B, Fe, and Al, in addition to H+Al, cation exchange capacity at pH = 7, Al saturation, soil organic matter, pH, sum of bases, base saturation, clay, and sand were accurately predicted (R2 > 0.70) using pXRF data, with emphasis on the prediction of Fe (R2 = 0.93), clay content (R2 = 0.81), H+Al (R2 = 0.81), and K+ (R2 = 0.85). The best predictive models were developed by RF and CR (86%) and when considering pXRF data + mining area + stage of rehabilitation (73%). The results highlight the potential of pXRF to accurately assess soil properties in environmental rehabilitation areas in the Amazon region (yet scarcely evaluated under this approach), promoting a more agile and cheaper preliminary diagnosis compared to traditional methods.

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The district of Arauca is the second-largest producer of cacao in Colombia. However, despite its quality, it faces issues for export due to levels of cadmium (Cd) higher than the regulatory thresholds. A central question is how it may impact agricultural performance in the presence of Cd in cacao and chocolates. This study quantified Cd in cacao plantations from Arauca. Thus, 180 farms were assessed in the municipalities of Arauquita, Fortul, Saravena, and Tame. Five sample types (soil, irrigation channel sediment, soil litter, cacao seeds, and chocolates) were assessed for Cd. As a technological innovation, the new MXRF technology was used for Cd in chocolates. The sequence of Cd content was soil litter > chocolate > soils > cacao seeds > irrigation-channel sediment. A gradient north-south of Cd content in soil was observed, where highest content was found in farms near the Arauca River, and lower farther away. In irrigation channel sediment, Cd levels averaged 0.07 mg kg-1. The Cd content in cacao seeds was 0.78 mg kg-1 on average. Cd content in chocolates was above the threshold (1.10 mg kg-1 on average, including several cacao mass percentages). These artisanal chocolate bars produced by single farms were near the limit of Cd set by the European Union (up to 0.8 mg kg-1). Therefore, mixing beans from different farms could reduce their Cd content. The present study underscores the complexity of Cd distribution, emphasizing the importance of integrating soil, crop, and landscape features in managing and mitigating Cd levels in cacao.

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Objetivo: estimar a oviposição e distribuição espacial de vetores Aedes durante a estação de inverno e correlacionar essas estimativas com dados climáticos do mesmo período. Métodos: estudo de campo conduzido no município de Barbacena-MG, em 2018. O monitoramento, a coleta de ovos e a estimativa de índices estegômicos de vetores Aedes foram obtidos por meio de ovitrampas. Os Índices de Densidade de Ovos (IDO) e de Positividade de Ovitrampas (IPO%) foram estimados conforme estações climáticas e semanas epidemiológicas. A correlação entre parâmetros meteorológicos (temperatura/pluviometria) e índices estegômicos (IDO/IPO) foi determinada pelo coeficiente de Spearman. Resultados: um total de 1.080 ovitrampas, instaladas em 39 bairros, foi analisado durante 10 semanas epidemiológicas, fornecendo um total de 970 ovos. Nas estações de outono, inverno e primavera, foram obtidos, respectivamente, 421, 470 e 70 ovos. Durante o outono, houve variação do IDO entre 14,2 e 34,2. O IPO manteve-se constante em 4,5%. Durante o inverno, houve variação do IDO entre 0,00 e 47,50 e do IPO entre 0,00% e 8,25%. Houve correlação negativa significativa tanto entre aumento da precipitação mensal e diminuição do número de ovos coletados (rho=-0.673) quanto entre aumento da precipitação mensal e diminuição do IPO (rho=-0.612). O valor geral do IDO e do IPO nas 10 semanas foi, respectivamente, 22,04 e 4,17% e, na estação de inverno, foi, respectivamente, 23,50 e 3,73%. Conclusão: os achados corroboram a presença de ovos e vetores do gênero Aedes mesmo em condições climáticas adversas para essas espécies e sustentam ações de manejo sanitário durante todo o ano.

Objective: to estimate oviposition and spatial distribution of Aedes vectors during the winter season and correlate these estimates with climate data from the same period. Methods: field study conducted in the municipality of Barbacena-MG in 2018. Monitoring, egg collection, and estimation of stegomic indices of Aedes were obtained using ovitraps. The Indices of Egg Density (EDI) and Positive Ovitrap (POI%) were estimated according to climatic seasons and epidemiological weeks. The correlation between meteorological parameters (temperature/rainfall) and stegomic indices (EDI/POI) was determined by the Spearman coefficient. Results: a total of 1,080 ovitraps installed in 39 neighborhoods were analyzed during ten (10) epidemiological weeks, providing a total of 970 eggs. In the autumn, winter, and spring seasons, 421, 470, and 70 eggs were obtained, respectively. During the autumn, there was a variation in EDI between 14.2­34.2. The POI remained constant at 4.5%. During the winter, the EDI varied between 0.00­47.50, and the POI varied between 0.00%­8.25%. There was a significant negative correlation, respectively, between an increase in monthly precipitation and a decrease in the number of eggs collected (rho=-0.673) and between an increase in monthly precipitation and a decrease in POI (rho=-0.612). The overall value of EDI and POI in the ten (10) weeks was 22.04 and 4.17%, and in the winter season, they were 23.50 and 3.73%, respectively. Conclusion: the findings corroborate the presence of eggs and vectors of the genus Aedes even in adverse climatic conditions for these species and support health management actions throughout the year.

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This study explores the application of a tyrosinase cantilever nanobiosensor for detecting 17ß-estradiol and estrone in typical water systems. The physical-chemical parameters of water were evaluated within the Tigre River micro-basin in Erechim, RS, to determine water potability for urban populations. Water clarity, conductivity, and pH levels were essential markers, adhering to recognized standards for water quality and human consumption. The cantilever nanobiosensor demonstrated strong sensitivity and a broad linear range, with a limit of detection (<0.00051 ppb) surpassing other enzymatic biosensors and covering a range of 0.0001-100 ppb. The real water sample quality investigated in relation to contamination with 17ß-estradiol and estrone by nanobiosensor showed values below the LOD for both compounds. Recovery studies demonstrated the reliability of the nanobiosensor. Selectivity tests indicated minimal interference from structurally similar substances. This study validates the nanobiosensor's potential for environmental monitoring and hormone detection, aligning with standard practices.

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Argentina is a leading honey producer and honey bees are also critical for pollination services and wild plants. At the same time, it is a major crop producer with significant use of insecticides, posing risks to bees. Therefore, the presence of the highly toxic insecticide chlorpyrifos, and forbidden contaminants (organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)) was investigated in honey bee, beebread, wax and honey samples in apiaries from three contrasting regions of Argentina. Chlorpyrifos was detected in all samples with higher levels during period 1 (spring) in contrast to period 2 (fall), agreeing with its season-wise use in different crops, reaching 3.05 ng/g in honey bees. A subsequent first-tier pesticide hazard analysis revealed that it was relevant to honey bee health, mainly due to the high concentrations found in wax samples from two sites, reaching 132.4 ng/g. In addition, wax was found to be the most contaminated matrix with a prevalence of OCPs (∑OCPs 58.23-172.99 ng/g). Beebread samples showed the highest concentrations and diversity of pesticide residues during period 1 (higher temperatures). A predominance of the endosulfan group was registered in most samples, consistent with its intensive past use, especially in Central Patagonia before its prohibition. Among the industrial compounds, lighter PCB congeners dominated, suggesting the importance of atmospheric transport. The spatio-temporal distribution of pesticides shows a congruence with the environmental characteristics of the areas where the fields are located (i.e., land use, type of productive activities and climatic conditions). Sustained monitoring of different pollutants in beekeeping matrices is recommended to characterize chemical risks, assess the health status of honey bee hives and the pollution levels of different agroecosystems. This knowledge will set a precedent for South America and be helpful for actions focused on the conservation of pollination services, apiculture and ecosystems in Argentina.

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Understanding the processes of mobility and availability of potentially toxic elements in soil is crucial for informed decision-making in the development of public policies aimed at minimizing environmental impacts. Monitoring, in combination with the determination of natural concentrations, can provide effective tools for controlling pollution sources. In this study, enrichment, pollution, and ecological risk indices were used for some potentially toxic elements in an anthropogenically influenced watershed in southwestern Bahia, Brazil. The study involved 63 composite surface soil samples collected from areas with natural forest, crops, pastures, and urbanization. The samples were analyzed for fertility and particle size. Metal extraction followed the EPA 3051A method, and element determination was carried out via ICP-OES. The soils in the Verruga River watershed exhibit a high variability in fertility and granulometric attributes. The Kruskal-Wallis test at a 5% significance level was employed to assess the impact of land management on the availability of elements (As, Co and Pb), while Spearman's correlation, along with hierarchical clustering analysis, was used to comprehend element dynamics. Geostatistics were applied to identify pollution hotspots. Consequently, it became evident that potentially toxic elements can accumulate in the soil depending on land use and management practices (As, Co, and Pb), as well as the weathering process linked to the type of source material, such as diamictite deposits (Ni and Co). Soils in the Verruga River watershed qualify as having minimal enrichment, low pollution levels, and individual ecological risk concerning Cd. The percentage of samples enriched with Cu, As, Zn, and Cd exceeded 67%, with agricultural activities being the primary source of pollution. Meanwhile, in pasture and urban areas, Co and Pb were notably prominent, respectively.

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The geochemical processes involved in the Amazon soils formation are not totally understood because its geological and pedological features were formed during different geological events and different times. The Southwestern region of Amazonas State is an example of a region where the soils were developed from rocks formed by sedimentary processes and, nowadays, the soils continue receiving seasonal inputs from the Andes sediments. Data on geochemical patterns of this region are scarce, and there is no information about the possible effects of the natural or unnatural enrichment of potentially toxic elements (PTEs). Thus, this study represents the first research into the geochemical patterns of PTEs in soils of Southwestern Amazonas State. Further, we carried out a human health risk assessment and a proposal for Quality Reference Values (QRV) for thirteen PTEs (As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Ti, V, Zn and Zr). Our findings showed that the PTEs contents in soil samples collected in the lowland areas are strongly influenced by sediments inputs, while samples localized in the highland areas are weakly influenced by sediments inputs and present depletion of PTEs. Barium, Cr, Cu, Ni and Pb were the PTEs most influenced by sediment's deposition. The soil contamination assessment showed the existence of enrichment of the potentially toxic elements in soil samples, which may be a consequence of the natural inputs of the Andean sediments. Furthermore, Co and Cr exceed the safety zone for carcinogenic risk assessment, which indicates the need to monitor these elements and their possible effects on the health of the population in this region.

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Abstract For places where non-sterile drug production occurs, regulatory bodies recommend monitoring of the environmental bioburden. This procedure provides information regarding possible microbiological risks to which the products may be exposed, so that subsequent action measures may be implemented. The aim of the present work was to quantify and characterize the microorganisms present in Grade D (ISO 8) cleanrooms of a Brazilian pharmaceutical industry, identifying any possible seasonal climatic influences on these environments. Sampling was performed by surface and air monitoring, over 12 months during the year 2019, in rooms that were in operation. For both sampling methods, no statistically significant differences in bacteria and fungi counts were found between months or seasonal periods. Microorganisms that presented higher incidence included Staphylococcus epidermidis (15%) and Micrococcus spp. (13%), common to the human microbiota, and the fungi Cladosporium sp. (23%) and Penicillium sp. (21%), typical of the external environment. The results showed that microbial contamination in the Grade D cleanrooms was within the permissible maximum levels and remained similar throughout the year. Microbiological quality control in the clean areas of the pharmaceutical industry investigated was considered effective, with regular maintenance being necessary to keep bioburden levels controlled.

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Resumo Objetivo Avaliar a eficácia antimicrobiana de um dispositivo fixo emissor de luz UV-C na desinfecção de diferentes superfícies do ambiente hospitalar e sua eficácia antifúngica na qualidade do ar. Métodos Estudo quase-experimental realizado em uma unidade de internação hospitalar, que utilizou o Bioamostrador de ar Andersen® de seis estágios para análise do ar; e na avaliação das superfícies, utilizaram-se três suspensões de microrganismos (Acinetobacter sp. MDR, Escherichia coli e Klebsiella pneumoniae produtora de KPC) para contaminar o ambiente. Para ambos foram feitas coletas pré (controle) e pós-acionamento da luz UV-C (teste). Resultados Na avaliação do ar houve uma redução importante da contagem de colônias após a luz UV-C e não foram encontrados fungos patogênicos ou toxigênicos em nenhum dos dois momentos. Em relação à desinfecção das superfícies, nenhum crescimento bacteriano foi observado após a intervenção da luz, demonstrando 100% de inativação bacteriana nas condições testadas. Conclusão A utilização da tecnologia com emissão de luz UV-C fixa foi eficaz e pode ser considerada uma intervenção promissora para protocolos de desinfecção de superfícies hospitalares.

Resumen Objetivo Evaluar la eficacia antimicrobiana de un dispositivo fijo emisor de luz UV-C para la desinfección de diferentes superficies del ambiente hospitalario y su eficacia antifúngica en la calidad del aire. Métodos Estudio cuasi experimental realizado en una unidad de internación hospitalaria, en que se utilizó el biomuestreador de aire Andersen® de seis etapas para el análisis del aire. En el análisis de las superficies, se utilizaron tres suspensiones de microorganismos (Acinetobacter sp. MDR, Escherichia coli y Klebsiella pneumoniae productora de KPC) para contaminar el ambiente. En ambos se tomó una muestra antes (control) y después de accionar la luz UV-C (prueba). Resultados En el análisis del aire hubo una reducción importante del recuento de colonias después de la luz UV-C y no se encontraron hongos patógenos ni toxigénicos en ninguno de los dos momentos. Con relación a la desinfección de las superficies, no se observó ningún crecimiento bacteriano después de la intervención de la luz, lo que demuestra un 100 % de inactivación bacteriana en las condiciones analizadas. Conclusión El uso de la tecnología con emisión de luz UV-C fija fue eficaz y puede ser considerada una intervención prometedora para protocolos de desinfección de superficies hospitalarias.

Abstract Objective To evaluate a fixed UV-C light emitting device for its antimicrobial effectiveness in the disinfection of distinct surfaces and its antifungal effectiveness on air quality in the hospital environment. Methods This quasi-experimental study was conducted in a hospital inpatient unit, in which a six-stage air Biosampler (Andersen®) was used for air analysis. In the evaluation of surfaces, three suspensions of microorganisms (Acinetobacter sp. multidrug-resistant, Escherichia coli, and KPC-producing Klebsiella pneumoniae) were used to contaminate the environment. In both evaluations, pre- (control) and post-activation of UV-C light (test) collections were made. Results In the air evaluation, an important reduction was observed in the colony count after irradiation with UV-C light, and pathogenic or toxigenic fungi were not found in either of the two moments. Regarding the disinfection of surfaces, no bacterial growth was observed after the application of UV-C light, showing 100% bacterial inactivation under the tested conditions. Conclusion The use of fixed UV-C light emission technology was effective and can be considered a promising intervention for hospital surface disinfection protocols.

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Certified laboratory animals in terms of health and genetic conditions are essential for obtaining reproducible and universal experimental results. In laboratory animal facilities, animals are housed under protective sanitary barriers designed to exclude and prevent the entry of infectious and microbial agents, thus ensuring not only an adequate and defined sanitary standard, but also animal welfare. Environment monitoring of an animal facility aims to assess the effiectiveness of adopted procedures for cleaning and disinfecting, air system quality and good management practices. In this work, petri dishes of nutrient agar were used, exposed in different locations in the room, and the results presented as “colony forming units - CFU after the exposure period, were used to validate and certify the processes used in the evaluated area. Environmental monitoring is extremely important in animal facilities as it is part of a comprehensive monitoring program and is useful for alerting professionals about the need to improve procedures and revise Standard Operating Procedures (SOPs). All of these elements contribute to produce quality animals that meet the needs of biomedical research and regulatory agencies.

RESUMO

The present study evaluates the endocrine effect in flatfish through vitellogenin (vtg) gene expression and its association with pollutants data obtained from fish muscle and sediment from two regions in the Gulf of Mexico (GoM): Perdido Fold Belt (northwestern) and the Yucatan Peninsula (southeast). The results revealed induction of vtg in male flatfish in both geographical regions with different levels and patterns of distribution per oceanographic campaign (OC). In the Perdido Fold Belt, vtg was observed in male fish during four OC (carried out in 2016 and 2017), positively associated with Pb, V, Cd and bile metabolites (hydroxynaphthalene and hydroxyphenanthrene). In the Yucatan Peninsula, the induction of vtg in males was also detected in three OC (carried out in 2016 and 2018) mainly associated with Ni, Pb, Al, Cd, V and polycyclic aromatic hydrocarbons. Ultimately, estrogenic alterations could affect reproductive capacity of male flatfish in the GoM.

Assuntos

RESUMO

Despite the undeniable effect of vaccination against COVID-19 in reducing disease severity, there is still a need to monitor and limit SARS-CoV-2 circulation and transmission. Thus, this study evaluated the presence of the SARS-CoV-2 genome on the surfaces of highly touched objects manipulated in the biological sample collection point and at the reception unit of the diagnostic laboratory. Surfaces were sampled once a week, for 6 weeks, between September 18th and October 23rd, 2020. RT-qPCR was used for SARS-CoV-2 detection. The coolers for biological sample transportation and the envelope containing the patient form were the objects with the highest occurrence of viral genome detection, although it was detected in each object in only two of the 6 evaluations. And the SARS-CoV-2 genome was detected just once on the vehicle steering wheel, computer keyboard, bathroom door handle and disinfection bench. The virus genome was not detected in any object on three of the six evaluations. And eight was the largest number of surfaces contaminated by the virus genome on one occasion. The reduced incidence of object contamination by the SARS-CoV-2 genome can be explained by the exposure of the objects to environmental conditions and the adoption of virus-spread containment measures. It can also reflect the low incidence of SARS-CoV-2 during the study's development period. Despite the low frequency of SARS-CoV-2 genome detection, our findings show that the virus was present in the environment at some point. This highlights the importance of adopting personal preventive measures to reduce respiratory virus spread, especially during epidemics and outbreaks.

RESUMO

As the monitoring of carbon dioxide is an important proxy to estimate the air quality of indoor and outdoor environments, it is essential to obtain trustful data from CO2 sensors. However, the use of widely available low-cost sensors may imply lower data quality, especially regarding accuracy. This paper proposes a new approach for enhancing the accuracy of low-cost CO2 sensors using an extremely randomized trees algorithm. It also reports the results obtained from experimental data collected from sensors that were exposed to both indoor and outdoor environments. The indoor experimental set was composed of two metal oxide semiconductors (MOS) and two non-dispersive infrared (NDIR) sensors next to a reference sensor for carbon dioxide and independent sensors for air temperature and relative humidity. The outdoor experimental exposure analysis was performed using a third-party dataset which fit into our goals: the work consisted of fourteen stations using low-cost NDIR sensors geographically spread around reference stations. One calibration model was trained for each sensor unit separately, and, in the indoor experiment, it managed to reduce the mean absolute error (MAE) of NDIR sensors by up to 90%, reach very good linearity with MOS sensors in the indoor experiment (r2 value of 0.994), and reduce the MAE by up to 98% in the outdoor dataset. We have found in the outdoor dataset analysis that the exposure time of the sensor itself may be considered by the algorithm to achieve better accuracy. We also observed that even a relatively small amount of data may provide enough information to perform a useful calibration if they contain enough data variety. We conclude that the proper use of machine learning algorithms on sensor readings can be very effective to obtain higher data quality from low-cost gas sensors either indoors or outdoors, regardless of the sensor technology.

Assuntos