Artículos científicos
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Ítem Agriculture without paraquat is feasible without loss of productivity lessons learned from phasing out a highly hazardous herbicide(Springer Nature Link, 2023-01-09) Stuart, Alexander M.; Merfield, Charles N.; Horgan, Finbarr G.; Willis, Sheila.; Watts, Meriel A.; Ramírez-Muñoz, Fernando; Sánchez U., Jorge.; Utyasheva, Leah.; Eddleston, Michael.; Davis, Mark L.; Neumeister, Lars.; Sanou, Manoé R.; Williamson, Stephanie.A small proportion of the thousands of pesticides on the market today are associated with a disproportionately high incidence of severe acute pesticide poisoning and suicide. Paraquat stands out as one of the most lethal pesticides in common use, frequently involved in fatal incidents due to suicides or accidental exposure. Even though paraquat has been banned in over 67 countries, it is still widely used in many others, particularly in Asia and Latin America. Based on a literature review and consultations, this paper identifes options for replacing paraquat and distils practical lessons from numerous successes around the world. Our aim is to support regulators, policymakers, agronomists and the supply chain sector with practical information related to phasing out paraquat. Production data consistently failed to show any negative efects of banning paraquat on agricultural productivity. A wide range of alternative approaches to weed management and crop defoliation are available, many of which do not rely on herbicides. Over 1.25 million farmers in low- and middle-income countries (LMICs) successfully produce a range of crops for private voluntary standards (PVS) in food and fber supply chains which prohibit paraquat use. We conclude from the fndings of this study that eliminating paraquat will save lives without reducing agri- cultural productivity. Less hazardous and more sustainable alternatives exist. To enhance successful adoption and uptake of these methods on a wide scale, farmers require training and support within an enabling policy environment.Ítem Pesticides in soil, groundwater and food in Latin America as part of one health(Springer Nature Link, 2024-02-08) Hilber, Isabel; Bahena Juárez, Fernando; Chiaia Hernández, Aurea C.; Elgueta, Sebastian; Escobar Medina, Arturo; Friedrich, Karen; Gonzáles Curbelo, Miguel Angel; Grob, Yael; Martín Fleitas, Marisleydis; B. Miglioranza, Karina S.; Peña Suárez, Brizeidi.; Pérez Consuegra, Nilda.; Ramírez Muñoz, Fernando; Sosa Pacheco, Dayana; Bucheli, Thomas D.We here report of a conference about “Pesticides in Soil, Groundwater and Food in Latin America as part of One Health” that took place at the “IV Seminario Internacional de Sanidad Agropecuaria (SISA)” in Varadero, Cuba, 8–12 May 2023. Researchers of Latin America (Argentina, Brazil, Chile, Costa Rica, Colombia, Cuba, Mexico) and Switzerland (workshop initiator) held presentations about occurrence and efects of pesticides on the environment, human health, the replacement of highly hazardous pesticides (HHP) by agroecological alternatives and the agri-food value chain. In a subsequent round table discussion, the presenters identifed defcits, needs, interests and opportunities. According to them, the lack of awareness of pesticide use afects the health and safety of workers applying the chemicals. Despite Latin America representing the main agricultural area in the world with a very intense pesticide use, monitoring data of pesticides in soil, surface and groundwaters, food, as well as in humans are missing. Risks of pesticides to humans should be assessed so that authorities can withdraw or limit within “short time” the access to corresponding formulations on the market. Also, communication is not state of the art and should be improved as, e.g. the teaching of workers and farmers, how to correctly use and apply pesticides or the briefng of decision makers. Pollinators sufer from multiple stressors not the least due to pesticides, and alternatives are badly needed. On the technical side, the diferent analytical methods to determine residues of active ingredients and transformation products in matrices of concern should be harmonized among laboratories. Seven future actions and goals were identifed to overcome the above defcits. Next steps after the publishing of this conference report are to harmonize and complete the information status of the presenters by exchanging the results/data already present. Therefore, a platform of interaction to address issues described above and to enhance collaboration shall be created. Samples of diferent matrices shall be exchanged to harmonize the chemical analysis and establish interlaboratory comparisons. Such activities might be facilitated by joining international associations or organizations, where researchers can ofer their expertise, or by forming a new pesticide network for Central and South America that could present tailored projects to national and international organizations and funding agenciesÍtem Asociación entre la exposición ambiental a plaguicidas y cáncer en Costa Rica para los últimos 35 años(Universidad Nacional, Costa Rica, 2021) Santamaría Ulloa, C.; Ortíz, A.; Ramírez, F.; Salas, D.; Mora, A.; Montero López, M.; Gutiérrez, F.Esta investigación tiene como objetivo determinar si existe en Costa Rica una asociación entre la exposición ambiental a plaguicidas y la incidencia de cáncer y su sobrevida en los últimos 35 años. En una primera etapa exploraremos todas las localizaciones anatómicas de cáncer según grandes grupos funcionales. Posteriormente nos centraremos en cáncer de mama, próstata, ovario y aquellas otras localizaciones que hayan mostrado asociaciones significativas en la etapa exploratoria previa. Las principales fuentes de información serán: Registro Nacional de Tumores (Ministerio de Salud), Estadísticas Vitales, Proyecciones Oficiales de Población y Censo Nacional Agropecuario 1984 y 2014 (Instituto Nacional de Estadística y Censos) y Boletines Estadísticos Agropecuarios (Ministerio de Agricultura y Ganadería). La metodología consiste en la utilización de técnicas de análisis espacio-temporal y Sistemas de Información Geográfica para determinar si existe una asociación entre la exposición ambiental a plaguicidas y la incidencia de cáncer, así como entre sta exposición y la sobrevida de los pacientes luego de su primer diagnóstico. La estimación de tasas de incidencia de cáncer se hará a nivel de distrito según quinquenio. Se estimará un índice de exposición ambiental a plaguicidas a partir de datos de los Censos Agropecuarios del INEC y de los Boletines Estadísticos agropecuarios del MAG. Mediante análisis de regresión espacial se determinará la magnitud de la asociación. El alcance de esta investigación es informar la política sanitaria en temas de exposición a plaguicidas y cáncer.Ítem Exposure to an environmentally relevant concentration of chlorpyrifos induces transcriptional changes and neurotoxicity in Poecilia gillii without clear behavioral effects(Elsevier, 2025-02-12) Sánchez-González, Daniel; Blanco Peña, Kinndle; Solano-Campos, Frank; Solano Díaz, Karla; Mena Torres, Freylan GerardoOverusing chlorpyrifos (CPF) in tropical countries such as Costa Rica poses a potential risk to freshwater ecosystems. This study investigated the effects of transient exposure to an environmentally relevant CPF concentration on the native fish species Poecilia gillii, employing a comprehensive approach that evaluated multiple levels of biological organization. Using RT-qPCR, we quantified transcript changes in genes involved in various biological processes, including inflammation and apoptosis; annexin A1 (anxa1b), cytokine regulation; cytokine-inducible SH2-containing protein (cish), redox reactions; NADH oxidoreductase subunit A2 (ndufa2), protein translocation; Sec61 gamma subunit (sec61g), and biotransformation; glutathione S-transferase rho (gstr). Additionally, we measured biochemical biomarkers such as phase I; 7-ethoxyresorufin-O-deethylase (EROD) and phase II; glutathione S-transferase (GST) biotransformation enzymes, oxidative stress markers; catalase (CAT) and lipid peroxidation (LPO), and conducted behavioral tests to assess swimming fitness and antipredator reactions. Neurotoxicity was assessed by measuring brain and muscle tissue cholinesterase (ChE) activity. Following 48 h of exposure to 5.5 µg/L CPF, we observed significant downregulation of the sec61g and gstr genes, decreased CAT activity, and neurotoxic effects, as indicated by reduced ChE activity in muscle. Although no significant behavioral changes were detected, our results suggest that short-term exposure to environmentally relevant CPF concentrations can disrupt gene expression, compromising biotransformation and protein synthesis in P. gillii juveniles. Moreover, the observed neurotoxicity, which is consistent with the mechanism of action of CPF, may lead to subtle behavioral changes. This study provides evidence of the sublethal effects of CPF on nontarget organisms, highlighting the importance of considering gene expression changes when assessing CPF toxicity.Ítem The Epidemic of Chronic Kidney Disease of Unknown Etiology in Mesoamerica: A Call for Interdisciplinary Research and Action(Asociación Estadounidense de Salud Pública, 2013-11) Wesseling Hoogervors, Catharina; Crowe, Jennifer; Hogstedt, Christer; Jakobsson, Kristina; Lucas, Rebekah; Wegman, David H.Los autores discuten la necesidad de una investigación colaborativa e interdisciplinaria para abordar la epidemia regional de enfermedad renal crónica de origen desconocido (CKDu), o nefropatía mesoamericana (MeN), en México y Centroamérica. Exploran varias teorías sobre la causa de la MeN, incluida la deshidratación y el estrés por calor, el uso de medicamentos antiinflamatorios no esteroides (AINE) y la dieta alta en fructosa. También abogan por la investigación sobre factores de riesgo ocupacional, marcadores bioquímicos y análisis de biopsias.Ítem Cambios en la superficie sembrada de palma aceitera en el cantón de Osa, Puntarenas. Período 2014-2018(Universidad Nacional, Costa Rica, 2020-06-29) Salas Gonzáles, Denis MauricioEl cultivo de palma aceitera muestra un acelerado crecimiento a nivel mundial. Según datos oficiales, solo en la región latinoamericana se evidencia un crecimiento del 150,8% en el área cultivada de palma de aceite al pasar de 443 000 hectáreas en 2001 a 1 111 000 hectáreas sembradas en 2014, de las cuales 818 000 se encontraban en etapa productiva aportando cerca del 6% del aceite de palma producido en el mundo (González, 2016). Estas plantaciones han impactado los paisajes tropicales por la disminución de la vegetación natural, pastos o por el reemplazo de otros cultivos. La expansión del cultivo de palma de aceite aumentó en Costa Rica y de acuerdo con la tendencia de los últimos años, seguirá en aumento. En los últimos años se han realizado censos y encuestas agropecuarias que muestran el crecimiento general, pero no detallan las áreas geográficas donde se da ese crecimiento y el consecuente impacto a la dinámica natural de las áreas cultivadas, información clave para los procesos de ordenamiento territorial regional y local que tenemos en el país. Por tal motivo, los objetivos de esta investigación fueron: analizar el cambio en la superficie sembrada con palma aceitera en el cantón de Osa, provincia de Puntarenas en el periodo 2014-2018 y evaluar la expansión del cultivo de palma aceitera en los distritos del cantón. Para esto, se analizaron datos de instituciones gubernamentales y se identificaron y digitalizaron las plantaciones de palma aceitera de los seis distritos del cantón de Osa.Ítem Medidas para la reducción del riesgo de contaminación ambiental con residuos de antibióticos y propagación de bacterias resistentes(Universidad Estatal a Distancia, Costa Rica, 2023-06-30) Villalobos Araya, Adriana; Estrada Konig, Sandra; Chaves Ramírez, Andrea; Rivera Castillo, Josué; Gutiérrez Espeleta, Gustavo; Chaverri Fonseca, Fabio; Blanco Peña, KinndleLa contaminación ambiental con antibióticos y la propagación de bacterias resistentes pueden provocar daños a la salud, el surgimiento de nuevas pandemias, la alteración del equilibrio de los ecosistemas, la inseguridad alimentaria y una crisis económica mundial. Ante este contexto, se plantea un análisis documental de las causas y consecuencias del problema, con el propósito de proponer medidas para la reducción de los riesgos. Como resultado de la investigación, se plantea el abordaje de la problemática a partir del enfoque “Un mundo, una salud”, donde es fundamental la implementación de buenas prácticas para la prevención de enfermedades infecciosas y el uso óptimo de antibióticos en la salud humana, animal y vegetal. Esto debe estar acompañado de procesos de investigación y concientización social, participación ciudadana, incidencia y gestión política, que permitan conservar un ambiente sano y ecológicamente equilibrado.Ítem Anthropogenic imprint on riverine plasmidome diversity and proliferation of antibiotic resistance genes following pollution and urbanization(Universidad Nacional, Costa Rica, 2025-03-24) Arias-Andrés, María; Barrantes-Jiménez, KeniaPlasmids are key determinants in microbial ecology and evolution, facilitating the dissemination of adaptive traits and antibiotic resistance genes (ARGs). Although the molecular mechanisms governing plasmid replication, maintenance, and transfer have been extensively studied, the specific impacts of urbanization-induced pollution on plasmid ecology, diversity, and associated ARGs in tropical regions remain underexplored. This study investigates these dynamics in a tropical aquatic ecosystem, providing novel insights into how pollution shapes plasmid composition and function. In contrast to the observed decrease in chromosomal diversity, we demonstrate that pollution associated with urbanization increases the diversity and taxonomic composition of plasmids within a bacterial community (plasmidome). We analyzed eighteen water and sediment metagenomes, capturing a gradient of pollution and ARG contamination along a tropical urban river. Plasmid and chromosomal diversity profiles were found to be anti-correlated. Plasmid species enrichment along the pollution gradient led to significant compositional differences in water samples, where differentially abundant species suggest plasmid maintenance within specific taxonomic classes. Additionally, the diversity and abundance of ARGs related to the plasmidome increased concomitantly with the intensity of fecal and chemical pollution. These findings highlight the critical need for targeted plasmidome studies to better understand plasmids' environmental spread, as their dynamics are independent of chromosomal patterns. This research is crucial for understanding the consequences of bacterial evolution, particularly in the context of environmental and public health.Ítem A case study on pharmaceutical residues and antimicrobial resistance genes in Costa Rican rivers : a possible route of contamination for feline and other species(Elsevier, 2023-11-12) Vargas-Villalobos, Seiling; Hernández, Felix; Fabregat-Safont, David; Salas-González, Denis; Quesada-Alvarado, Francisco; Botero-Coy, Ana Maria; Esperón, Fernando; Martín-Maldonado, Bárbara; Monrós-González, Juan; Ruepert, Clemens; Estrada-König, Sandra; Rivera-Castillo, Josué; Chaverri-Fonseca, Fabio; Blanco-Peña, KinndleIn this investigation, the presence of antibiotics and pharmaceuticals in Costa Rican surface waters, specifically in regions near feline habitats, was examined. The study revealed that 47% of the water samples contained detectable traces of at least one antibiotic. Ciprofloxacin and norfloxacin were the most frequently detected compounds, each with a detection rate of 27%. Other antibiotics, such as erythromycin, roxithromycin, and trimethoprim, were also found but at lower frequencies, around 14%. Notably, all antibiotic concentrations remained below 10 ng/L, with ciprofloxacin, norfloxacin, and erythromycin showing the highest concentrations. Furthermore, the investigation revealed the presence of non-antibiotic pharmaceutical residues in the water samples, typically at concentrations below 64 ng/L. Tramadol was the most frequently detected compound, present in 18% of the samples. The highest concentrations were observed for acetaminophen and tramadol, measuring 64 and 10 ng/L, respectively. Comparing these findings with studies conducted in treated wastewater and urban rivers, it became evident that the concentrations of antibiotics and pharmaceuticals were notably lower in this study. While previous research reported higher values, the limited number of studies conducted in protected areas raises concerns about the potential environmental impact on biodiversity. In summary, these results emphasize the importance of monitoring pharmaceutical residues and antimicrobial resistance genes ARGs in vulnerable ecosystems, especially those in close proximity to feline habitats in Costa Rica. Additionally, the study delved into the detection of (ARGs). All tested water samples were positive for at least one ARG, with the blaTEM gene being the most prevalent at 82%, followed by tetS at 64% and qnrB at 23%. Moreover, this research shed light on the complexity of evaluating ARGs in environmental samples, as their presence does not necessarily indicate their expression. It also highlighted the potential for co-selection and coregulation of ARGs, showcasing the intricate behaviors of these genes in aquatic environments.Ítem Pyrimethanil and chlorpyrifos air concentrations and pregnant women’s urinary metabolites in the Infants’ Environmental Health Study (ISA), Costa Rica(Elsevier, 2022-05-27) Giffin, Andrew; Hoppin, Jane A.; Córdoba, Leonel; Solano, Karla; Ruepert, Clemens; Peñaloza Castañeda, Jorge; Lindh, Christian; Reich, Brian J.; Wendel de Joode, Berna vanOnly few studies have compared environmental pesticide air concentrations with specific urinary metabolites to evaluate pathways of exposure. Therefore, we compared pyrimethanil and chlorpyrifos concentrations in air with urinary 4-hydroxypyrimethanil (OHP, metabolite of pyrimethanil) and 3,5,6-trichloro-2-pyridinol (TCPy, metabolite of chlorpyrifos) among pregnant women from the Infant's Environmental Health Study (ISA) in Matina County, Costa Rica. During pregnancy, we obtained repeat urinary samples from 448 women enrolled in the ISA study. We extrapolated pyrimethanil and chlorpyrifos concentrations measured with passive air samplers (PAS) (n = 48, from 12 schools), across space and time using a Bayesian spatiotemporal model. We subsequently compared these concentrationswith urinary OHP and TCPy in 915 samples from 448 women, usingseparatemixed models andconsidering several covariables. A 10% increase in air pyrimethanil (ng/m3) was associated with a 5.7% (95% confidence interval (CI 4.6, 6.8) increase in OHP (μg/L). Women living further from banana plantations had lower OHP: -0.7% (95% CI -1.2, -0.3) for each 10% increase in distance (meters) as well as women who ate rice and beans ≥15 times a week -23% (95% CI -38, -4). In addition, each 1 ng/m3 increase in chlorpyrifos in air was associated with a 1.5% (95% CI 0.2, 2.8) increase in TCPy (μg/L), and women working in agriculture tended to have increased TCPy (21%, 95% CI -2, 49). The Bayesian spatiotemporal models were useful to estimate pyrimethanil and chlorpyrifos air concentrations across space and time. Our results suggest inhalation of pyrimethanil and chlorpyrifos is a pathway of environmental exposure. PAS seems a useful technique to monitor environmental current-use pesticide exposures. For future studies, we recommend increasing the number of locations of environmental air measurements, obtaining all air and urine measurements during the same month, and, ideally, including dermal exposure estimates as well.Ítem The fungicide chlorothalonil changes the amphibian skin microbiome: a potential factor disrupting a host disease-protective trait(MDPI, 2021-04-08) Jiménez, Randall R.; Alvarado, Gilbert; Ruepert, Clemens; Ballestero, Erick.; Sommer, SimoneThe skin microbiome is an important part of amphibian immune defenses and protects against pathogens such as the chytrid fungus Batrachochytrium dendrobatidis (Bd), which causes the skin disease chytridiomycosis. Alteration of the microbiome by anthropogenic factors, like pesticides, can impact this protective trait, disrupting its functionality. Chlorothalonil is a widely used fungicide that has been recognized as having an impact on amphibians, but so far, no studies have investigated its effects on amphibian microbial communities. In the present study, we used the amphibian Lithobates vibicarius from the montane forest of Costa Rica, which now appears to persist despite ongoing Bd-exposure, as an experimental model organism. We used 16S rRNA amplicon sequencing to investigate the effect of chlorothalonil on tadpoles’ skin microbiome. We found that exposure to chlorothalonil changes bacterial community composition, with more significant changes at a higher concentration. We also found that a larger number of bacteria were reduced on tadpoles’ skin when exposed to the higher concentration of chlorothalonil. We detected four presumed Bd-inhibitory bacteria being suppressed on tadpoles exposed to the fungicide. Our results suggest that exposure to a widely used fungicide could be impacting host-associated bacterial communities, potentially disrupting an amphibian protective trait against pathogens.Ítem Bacterial communities in residential wastewater treatmentplants are physiologically adapted to high concentrations of quaternary ammonium compounds(Wiley Online Library, 2023-08-28) Chacón, Luz; Rojas-Jimenez, Keilor; Arias-Andres, MariaBenzalkoniumchloride(BAC)isaquaternaryammoniumcompound(QAC)widely used as the active ingredient of disinfectants. Its excessive discharge into wastewater is constant and in high concentrations, likely affecting the physiology of microbial communities. We compared the physiological community profile of activated sludge (AS) bacteria with and without prior in vitro exposure to a high concentration of BAC(10 mg L−1). We measured the community functional diversity, carbon substrate multifunctionality, and the median effective concentration thatinhibits carbon respiration (EC50) using Biolog EcoPlates supplemented with a gradient of 0–50 mg L−1 of BAC. Surprisingly, we did not find significant differences in the physiological parameters among treatments. Certain abundant bacteria, including Pseudomonas, could explain the community’s tolerance to high concentrations of BAC. We suggest that bacterial communities in wastewater treatment plants’ AS are “naturally” adapted to BAC due to frequent and high-dose exposure. We highlight the need to understand better the effects of QACs in wastewater, their impact on the selection of tolerant groups, and the alteration in community metabolic profiles.Ítem Assessing habitat selection in the prawn Macrobrachium rosenbergii using the model toxicant copper and colonization as a test endpoint: Does prior exposure determine biochemical and behavioral responses?(Universidad Nacional, Costa Rica, 2024-08-20) Mena, F; Echeverría-Sáenz, Silvia; Brenes-Bravo, Gabriel; Araújo, Cristiano VM; Moreira-Santos, MatildeHabitat selection by aquatic organisms is dependent on the availability of adequate conditions to support life and the benefits that the habitat provides. Contaminated environments tend to be less attractive to organisms because reduced habitat quality leads to increased maintenance costs. Consequently, reduced colonization of such disturbed habitats is an expected response. However, colonization has been understudied as an ecotoxicological test endpoint, despite its proven ability to assess habitat selection by populations across various taxa. The aim of the present study was to investigate whether previous exposure to copper could alter the colonization behavior of the freshwater prawn Macrobrachium rosenbergii along a non-forced exposure gradient of interconnected copper- contaminated habitats (0 to 500 µg/L) due to physiological and behavioral impairments. To assess this, post- larvae of M. rosenbergii were pre-exposed to 0, 50, 250 and 500 µg/L copper for a maximum period of 48 h. The physiological status and motility of the organisms after pre-exposure to copper were evaluated using behavioral endpoints (swimming activity by video tracking) and biochemical biomarkers (biotransformation, oxidative stress and neurotoxicity). The results indicated that pre-exposure to copper (at concentrations of 0, 50 and 500 µg/L) significantly influenced the median colonization concentration (CC50), which decreased from 270 µg/L to 109 µg/L. None of the assessed swimming parameters (speed, motility rate, exploration rate, and total distance) were affected by the pre-exposure to copper (0, 50 and 250 µg/L). Biochemically, cholinesterase levels were only affected in the prawn population exposed to 250 µg/L of copper. The present study provides a better understanding of the relevance of colonization as an ecotoxicological endpoint for assessing the spatial distribution of populations, including both new inhabitants and previously exposed organisms, in recovering habitats.Ítem A multidisciplinary approach to analyze the antimicrobial resistance in natural ecosystems(Universidad Nacional, Costa Rica, 2024-02-25) Blanco-Pena, K; Quesada-Alvarado, Francisco; Salas-González, Denis; Chaverri-Fonseca, FabioAntimicrobial Resistance (AMR) poses a global threat to both human health and environmental well-being. Our study delved into Costa Rican wildlife reserves, uncovering a substantial human impact on these ecosystems and underscoring the imperative to pinpoint AMR hotspots. Embracing a One Health perspective, we advocated for a comprehensive landscape analysis that intricately intertwined geographic, climatic, forest, and human factors. This study illuminated the link between laboratory results and observed patterns of antimicrobial use, thereby paving the way for sustainable solutions. Our innovative methodology involved deploying open-ended questions to explore antimicrobial usage across livestock activities, contributing to establishing a comprehensive methodology. Non-invasive sampling in wildlife emerged as a critical aspect, shedding light on areas contaminated by AMR. Feline species, positioned at the apex of the food chain, acted as sentinels for environmental health due to heightened exposure to improperly disposed waste. Regarding laboratory findings, each sample revealed the presence of at least one antimicrobial resistance gene (ARG). Notably, genes encoding resistance to tetracyclines dominated (94.9%), followed by beta-lactams (75.6%), sulfonamides (53.8%), aminoglycosides (51.3%), quinolones (44.9%), phenicols (25.6%), and macrolides (20.5%). Genes encoding polymyxins were not detected. Moreover, 66% of samples carried a multi-resistant microbiome, with 15% exhibiting resistance to three antimicrobial families and 51% to four. The absence of a correlation between forest coverage and ARG presence underscored the profound human impact on wildlife reserves, surpassing previous estimations. This environmental pressure could potentially modify microbiomes and resistomes in unknown ways. As not all antimicrobial families encoding ARGs were utilized by farmers, our next step involved evaluating other human activities to identify the primary sources of contamination. This comprehensive study contributed crucial insights into the intricate dynamics of AMR in natural ecosystems, paving the way for targeted interventions and sustainable coexistence.Ítem Sensibilidad de Hydra attenuata e Hydra viridis a los plaguicidas diuron y etoprofos, Costa Rica(Universidad Nacional, Costa Rica, 2023-09-01) Jones Peñaranda, Caroline; Ugalde, María del Rocío; Jiménez, Katherine; Mena, Freylan; Vargas, SeilingEl objetivo fue determinar cuál de las dos especies de hidras (Hydra attenuata o Hydra viridis) resultaba más sensible a dos plaguicidas, para luego usarla como parte de la batería de organismos de prueba del Laboratorio de Estudios Ecotoxicológicos (ECOTOX). Para esto se utilizaron diluciones de dos de los plaguicidas más comúnmente usados en el cultivo de piña en Costa Rica y detectados en muestras de agua: el herbicida diuron y el insecticida etoprofos. Se realizaron bioensayos de toxicidad con cada una de estas sustancias y con una mezcla de estas. Se registró el estado morfológico de las hidras. Además, se evaluaron la concentración de efecto medio (EC50), la concentración letal media (LC50), y las interacciones de toxicidad según tres posibilidades: antagónica, aditiva o sinérgica. [Resultados] La H. attenuata fue la especie más sensible a ambos plaguicidas, con LC50s de 16,84 mg/L y 103,01 mg/L; y EC50s de 4,24 mg/L y 23,74 mg/L para diuron y etoprofos, respectivamente. Mientras tanto la H. viridis tuvo LC50s de 36,94 mg/L y 103,01 mg/L, con EC50s de 13,64 mg/L y 53,12 mg/L, también para diuron y etoprofos, respectivamente. La exposición a la mezcla de plaguicidas solo causó mortalidad a la H. viridis y tuvo efecto sinérgico en ambas especies. Estos resultados sugieren que la H. attenuata es la especie más apropiada para la evaluación de efectos de plaguicidas, pero se deben realizar más estudios sobre las interacciones de los contaminantes en mezclas, porque estas pueden modificar su toxicidad para diferentes especies.Ítem The Impact of Urban Pollution on Plasmid-Mediated Resistance Acquisition in Enterobacteria from a Tropical River(Universidad Nacional, Costa Rica, 2024-11-14) Mendoza Guido, Bradd; Arias Andres, Maria; Barrantes, Kenia; Rodrıguez, Cesar; Rojas-Jimenez, KeilorThe exposure of environmental bacteria to contaminants in aquatic ecosystems accelerates the dissemination of antibiotic-resistance genes (ARGs) through horizontal gene transfer (HGT). In this study, we sampled three locations along a contamination gradient of a polluted river, focusing on isolating Enterobacteria from the surface waters to investigate the relationship between urban pollution and antibiotic resistance. The genomes of 15 isolates (5 per site) were sequenced to identify plasmid-borne ARGs and their association with resistance phenotypes. Results: Isolates from the site with the highest contamination (Site 3) showeda larger number of ARGs, plasmids, and resistance phenotypes. Notably, one of the isolates analyzed, E. coli A231-12, exhibited phenotypic resistance to seven antibiotics, presumably conferred by a single plasmid carrying 12 ARGs. Comparative analysis of this plasmid revealed its close evolutionary relationship with another IncH plasmid hosted by Salmonella enterica, underscoring its high ARG burden in the aquatic environment. Other plasmids identified in our isolates carried sul and dfrA genes, conferring resistance to trimethoprim/sulfamethoxazole, a commonly prescribed antibiotic combination in clinical settings. These results highlight the critical need to expand research on the link between pollution and plasmid-mediated antimicrobial resistance in aquatic ecosystems, which can act as reservoirs of ARGs.Ítem Benchmarking AI-based Plasmid Annotation Tools for Antibiotic Resistance Genes Mining From Metagenome of the Virilla River, Costa Rica(Universidad Nacional, Costa Rica, 2023-11-28) Rojas-Villalta, Dorian; Calderón-Osorno, Melany; Barrantes, Kenia; Arias-Andres, Maria; Rojas-Jiménez, KeilorBioinformatics and Artificial Intelligence (AI) stand as rapidly evolving tools that have facilitated the annotation of mobile genetic elements (MGEs), enabling the prediction of health risk factors in polluted environments, such as antibiotic resistance genes (ARGs). This study aims to assess the performance of four AI-based plasmid annotation tools (Plasflow, Platon, RFPlasmid, and PlasForest) by employing defined performance parameters for the identification of ARGs in the metagenome of one sediment sample obtained from the Virilla River, Costa Rica. We extracted and sequenced complete DNA from the sample, assembled the metagenome, and then performed the plasmid prediction with each bioinformatic tool, and the ARGs annotation using the Resistance Gene Identifier web portal. Sensitivity, specificity, precision, negative predictive value, accuracy, and F1-score were calculated for each ARGs prediction result of the evaluated plasmidomes. Notably, Platon emerged as the highest performer among the assessed tools, exhibiting exceptional scores. Conversely, Plasflow seems to face difficulties distinguishing between chromosomal and plasmid sequences, while PlasForest has encountered limitations when handling small contigs. RFPlasmid displayed diminished specificity and was outperformed by its taxon-dependent workflow. We recommend the adoption of Platon as the preferred bioinformatic tool for resistome investigations in the taxon-independent environmental metagenomic domain. Meanwhile, RFPlasmid presents a compelling choice for taxon-dependent prediction due to its exclusive incorporation of this approach. We expect that the results of this study serve as a guiding resource in selecting AI-based tools for accurately predicting the plasmidome and its associated genes.Ítem Pesticide use in banana plantations in Costa Rica - A review of environmental and human exposure, effects and potential risks.(Elsevier, 2023) Bruhl, Carsten A.; Arias Andrés, María; Echeverría Sáenz, Silvia; Bundschuh, Mirco; Knabel, Anja; Mena, Freylan; Petschick, Lara L.; Ruepert, Clemens; Stehle, SebastianBiodiversity is declining on a global scale. Especially tropical ecosystems, containing most of the planetary biodiversity, are at risk. Agricultural monocrop systems contribute to this decline as they replace original habitats and depend on extensive use of synthetic pesticides that impact ecosystems. In this review we use large-scale banana production for export purposes in Costa Rica as an example for pesticide impacts, as it is in production for over a century and uses pesticides extensively for more than fifty years. We summarise the research on pesticide exposure, effects and risks for aquatic and terrestrial environment, as well as for human health. We show that exposure to pesticides is high and relatively well studied for aquatic systems and humans, but hardly any data are available for the terrestrial compartment including adjacent non target ecosystems such as rainforest fragments. Ecological effects are demonstrated on an organismic level for various aquatic species and processes but are not available at the population and community level. For human health studies exposure evaluation is crucial and recognised effects include various types of cancer and neurobiological dysfunctions particularly in children. With the many synthetic pesticides involved in banana production, the focus on insecticides, revealing highest aquatic risks, and partly herbicides should be extended to fungicides, which are applied aerially over larger areas. The risk assessment and regulation of pesticides so far relies on temperate models and test species and is therefore likely underestimating the risk of pesticide use in tropical ecosystems, with crops such as banana. We highlight further research approaches to improve risk assessment and, in parallel, urge to follow other strategies to reduce pesticides use and especially hazardous substances.Ítem Contributions of the academy for a better understanding of the oceans in Costa Rica(Ministerio de Relaciones Exteriores y Culto, 2024-03) Morales-Ramírez, Álvaro; Gómez-Ramírez, Eddy; Alfaro-Martínez, Eric; Hidalgo, Hugo G.; Ulate-Naranjo, Karol; Arias-Andres, Maria; Rojas-Villalobos, Fresia; Samper-Villarreal, Jimena; Wehrtmann, Ingo S.El lanzamiento de la Década de los Océanos en el año 2017 estableció nuevas visiones entre la ciencia y política, para fortalecer la investigación y la gestión de los océanos y las costas. Con un 92% de superficie marina, Costa Rica es una nación de mar, que posee una gran diversidad marina, y que realiza esfuerzos para conocer mejor sus recursos costeros y marinos. En los últimos 20 años, se han desarrollado políticas para promover la gestión integrada de nuestras zonas costeras y la creación de áreas marinas protegidas. Mediante la investigación de las universidades públicas, conocemos mejor, aunque de manera incompleta, cómo se encuentran nuestros recursos pesqueros y acuicultura, los impactos de la contaminación marina y sus efectos sobre organismos y ecosistemas, los impactos del cambio climático, así como los esfuerzos para impulsar la conservación marina y la restauración de los ecosistemas marino-costeros y sus servicios. Del análisis de estas áreas de estudios, es evidente, que existen vacíos de información que deben ser abordados para generar más información científica que permita la toma de decisiones adecuadas y basadas en la ciencia, con el objeto de mejorar las políticas púbicas relacionadas a las zonas costeras, sus recursos, los servicios ecosistémicos, la gestión de las numerosas fuentes de contaminación continental que llegan a la costa y la adaptación al cambio climático.Ítem Identification of anthropogenic impact on natural habitats by antimicrobial resistance quantification in two neotropical wild cats and their geospatial analysis(BioOne COMPLETE, 2023) Angulo, Ana Sofía.; Fajardo, Fernando Esperón; Salom-Pérez, Roberto; Carazo Salazar, Javier; Taylor, Francisco; Pilé, Edwin; Quesada-Alvarado, Francisco; Blanco- Peña, KinndleHuman activities such as habitat degradation and fragmentation threaten biodiversity in Neotropical areas. This work proposes an analytical methodology to identify natural areas in Central America with anthropogenic impact, analyzing the presence of antimicrobial resistance genes (ARGs) in accordance with their theoretical relationship with human-related activities. Sixteen ARGs were quantified in feces of different individuals of 13 jaguars (Panthera onca) and 13 pumas (Puma concolor) in three conservation areas in Costa Rica by real-time PCR. At least one ARG was detected in all samples. Of the ARGs encoding tetracycline resistance, the most frequent were tetQ and tetY (85% and 69%, respectively). The sulfonamides (sulI and sulII; 69% each), phenicols (catI and catII; 19% and 54%, respectively), and quinolones (qnrS; 12%) were also detected. The presence of human settlements, livestock farms (pigs, cattle, and poultry), roads, human health centers, flood zones, and rivers were identified within each area to generate an index of human activity. We found no difference between the presence of ARG by roads, agricultural activities, and human settlements (P.0.05). However, tetW showed higher percentages with porcine and bovine farms; both tetY and tetW were more frequent in jaguars than in pumas. Of concern is that many of the most contaminated samples were taken from national parks, such as Braulio Carrillo and Tortuguero, where animals should not have direct contact with humans.