Artículos científicos

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14755

Examinar

Mostrando 1 - 20 de 127

A biogeochemical comparison of three representative lakes of Costa Rica
(Instituto Regional de Estudios en Sustancias Tóxicas, 2025-06-09) Esquivel-Hernández, Germain; Sánchez-Gutiérrez, Rolando; Arias, M.; Ugalde-Salazar, Rocío; Echeverría- Sáenz, Silvia
Lakes are widely distributed across Costa Rica, from coasts to the highest elevation regions and located in the main terrestrial biomes, yet updated biogeochemical information about the main types of lakes is still lacking. We present comparative biogeochemistry (water chemistry, stable isotopes, and picoplankton) for a coastal lake (Lake Madre de Dios), a volcanic lake (Lake Barva), and a glacial lake (Lake Ditkevi). Sampling was conducted between February and November 2022, including dry and rainy seasonal conditions. Hydrological and chemical conditions were evaluated using water and carbon stable isotopes, dissolved organic matter, major ions, and microbiota analysis. Isotopic data on water (δ2H and δ18O) and dissolved inorganic carbon (δ13CDIC) confirmed lower evaporative losses for the maar and tarn lakes and productivity response to precipitation inputs. Excitation/emission matrices confirmed the prevalence of fulvic and humic acids in the coastal and glacial lakes, mainly aromatic proteins and soluble microbial byproducts in the volcanic lake. Picophytoplankton (PPP, ∼0.2–10 μm) was mainly represented by phycocyanin-rich picocyanobacteria in the 3 lakes, but maar and tarn lakes had greater representation of phycoerythrin-rich picocyanobacteria. We confirmed fluctuations in PPP cell abundance in the lakes was lower than in comparable temperate lakes. For other eutrophic lakes, abundance of picocyanobacteria dominated over picoeukaryotic algae. This work aimed to promote an ecosystem approach to study the biogeochemical functioning of tropical lakes using a combination of chemical, hydrological, and biological data and to provide baseline information for future studies (e.g., climate change and pollution impacts) on tropical lakes of Costa Rica.
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, Fabio
Antimicrobial 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.
A participatory assessment of ecosystem services and human wellbeing in Rural Costa Rica using Photo-Voice
(Springer, 2012-03-09) Berbes-Blazquez, Marta
Human well-being is intricately connected to ecosystem services. A keystone contribution to the ecosystem service literature has been the Millennium Ecosystem Assessment, MA, (Ecosystems and human well-being: a framework for assessment, Island Press, Washington, DC; 2003, 2005). Much of the work on ecosystem services to date has focused on the assessment and classification of environmental functions. The need for inclusion of community perspectives in ecosystem assessments has been widely recognized in order to better understand the distribution of impacts and benefits resulting from natural resource use. Communities can offer a direct route to understanding the complex relationships between ecosystems and human well-being and how environmental management affects their livelihoods. Photovoice has been made popular as a tool for participatory needs assessment but it has had limited use in ecosystem assessments to date. The purpose of this paper is twofold: (1) to present the results of a community-level assessment of environmental services in a watershed dominated by pineapple monoculture in Costa Rica; and (2) to evaluate the strengths and the limitations of photovoice as a tool for mapping the relationship between ecosystems and people. I argue that photovoice is an underutilized methodology that has the potential to complement biophysical ecosystem service assessments in the context of impoverished and resource-dependent communities, particularly, since assessing ecosystem services and acting upon that information requires integrating the knowledges of diverse stakeholders, recognizing power imbalances, and grappling with the complexity of social-ecological systems. Processes such as photovoice have the potential to catalyze community self-organization, which is a critical component for empowerment.
A pilot field evaluation on heat stress in sugarcane workers in Costa Rica: What to do next?
(Universidad Nacional, Costa Rica, 2009) Van Wendel de Joode, Berendina; Wesseling Hoogervors, Catharina; Crowe, Jennifer
Climate change is producing major impacts including increasing temperatures in tropical countries, like Costa Rica, where the sugarcane industry employs thousands of workers who are exposed to extreme heat. Objectives: This article outlines a pilot qualitative evaluation of working conditions and heat in the sugarcane industry. Design: A literature review, direct observations and exploratory interviews with workers were conducted to reach a preliminary understanding of the dimensions of heat-related health issues in the sugarcane industry, as a basis for the design of future studies. Results: The industry employs temporary workers from Nicaragua and Costa Rica as well as year-round employees. Temporary employees work 12-hour shifts during the harvest and processing ('zafra') season. In many cases, sugarcane field workers are required to carry their own water and often have no access to shade. Sugar mill workers are exposed to different levels of heat stress depending upon their job tasks, with the most intense heat and workload experienced by the oven ('caldera') cleaners. Conclusions: Research is needed to achieve better understanding of the multiple factors driving and interacting with heat exposures in the sugarcane industry in order to improve the health and safety of workers while maintaining worker productivity. © 2009 Jennifer Crowe et al.
Acute health effects of organophosphorus pesticides on Tanzanian small-scale coffee growers
(Nature Publishing Group, 2001-07-01) Ngowi, Aiwerasia; Maeda, David; Partanen, Timo; Sanga, Michael
A cute health effects of organophosphorus (PP) pesticides on coffee farmworkers in 1991-1992 in Tanzania are reported to provide a basis for concern over farmworkers being overexposed during application. Workers exposed to OP pesticides (N = 133) were drawn from a population of about 240,000 coffee farmers. They were interviewed on symptoms and personal protection, and their erythrocyte acetylcholinesterase (ACHE) activity was determined during both spraying and nonspraying period. AChE activities during spraying and nonspraying period were comparable (mean 32.0, SD 7.8 vs. 33.0, SD 8.7 U/g HgB, P = 0.26). The prevalence of cough, headache, abdominal pain, excessive sweating, nausea, excessive salivation, diarrhea, and vomiting did not differ significantly between spraying and nonspraying periods. There was no suggestion of decreased AChE in exposed subjects who complained of OP-related symptoms compared to symptomless exposed subjects. Use of gloves, long boots, head cover, face cover, and coverall was not significantly associated with AChE activity. No marked AChE depression was found during spraying season, which may explain the lack of association between symptoms and ACHE. The fact that only moderately toxic OP pesticides were used may indicate that toxicity was not sufficiently high to cause depression. Experience, however, suggests that occupational poisoning remains a potential serious danger in coffee cultivation in Tanzania.
Acute, chronic and biochemical effects of chlorothalonil on Agalychnis callidryas, Isthmohyla pseudopuma and Smilisca baudinii tadpoles
(Springer, 2016-08-05) Méndez, Michael; Obando, Priscilla; Pinnock Branford, Margaret Verónica; Ruepert, Clemens; Castillo, Luisa E.; Mena, Freylan; Alvarado, Gilbert
Declines of amphibian populations have been a worldwide issue of concern for the scientific community during the last several decades. Efforts are being carried out to elucidate factors related to this phenomenon. Among these factors, pathogens, climate change, and environmental pollution have been suggested as possible causes. Regarding environmental pollutants, some pesticides are persistent in the environment and capable of being transported long distances from their release point. In Costa Rica, some pesticides have been detected in protected areas, at locations where amphibian populations have declined. Information about toxicity of pesticides used in Costa Rican agriculture to amphibians is still scarce, particularly for native species. Toxicity tests with chlorothalonil, a fungicide intensively used in Costa Rica, were carried out exposing tadpoles of three Costa Rican native species: Agalychnis callidryas, Isthmohyla pseudopuma, and Smilisca baudinii in order to evaluate acute and chronic toxicity as well as the biomarkers cholinesterase activity (ChE), glutathione-S transferase activity (GST), and lipid peroxidation (LPO). 96-h LC50: 26.6 (18.9–35.8) μg/L to A. callidryas, 25.5 (21.3–29.7) μg/L to I pseudopuma and 32.3 (26.3–39.7) μg/L to S. baudinii were determined for chlorothalonil. These three species of anurans are among the most sensitive to chlorothalonil according to the literature. Besides, GST was induced in S. baudinii after exposure to sub-lethal concentrations of chlorothalonil while evisceration occurred in S. baudinii and A. callidryas tadpoles exposed to lethal concentrations of the fungicide. Chronic exposure to sub-lethal concentrations accelerated development in S. baudinii and caused lesions in tail of S. baudinii and I. pseudopuma tadpoles. Our results demonstrate that chlorothalonil is highly toxic to native amphibian species and that low concentrations can cause biochemical responses related to phase II of biotransformation and effects on development.
Aerial application of mancozeb and urinary ethylene thiourea (ETU) concentrations among pregnant women in Costa Rica: the Infants' Environmental Health Study (ISA)
(Environmental Health Perspectives, 2014-12-01) van Wendel de Joode, Berna; Mora, Ana Maria; Cordoba, Leonel; Cano, Juan Camilo; Quesada, Rosario; Faniband, Moosa; Wesseling, Catharina; Ruepert, Clemens; Öberg, Mattias; Eskenazi, Brenda; Mergler, Donna; Lindh, Christian
Background: Mancozeb and its main metabolite ethylene thiourea (ETU) may alter thyroid function; thyroid hormones are essential for fetal brain development. In Costa Rica, mancozeb is aerially sprayed at large-scale banana plantations on a weekly basis. Objectives: Our goals were to evaluate urinary ETU concentrations in pregnant women living near large-scale banana plantations, compare their estimated daily intake (EDI) with established reference doses (RfDs), and identify factors that predict their urinary ETU concentrations. Methods: We enrolled 451 pregnant women from Matina County, Costa Rica, which has large-scale banana production. We visited 445 women up to three times during pregnancy to obtain urine samples (n = 872) and information on factors that possibly influence exposure. We determined urinary ETU concentrations using liquid chromatography mass spectrometry. Results: Pregnant women’s median urinary ETU concentrations were more than five times higher than those reported for other general populations. Seventy-two percent of the women had EDIs above the RfD. Women who lived closest (1st quartile, < 48m) to banana plantations on average had a 45% (95% CI: 23, 72%) higher urinary ETU compared with women who lived farthest away (4th quartile, ≥ 565m). Compared with the other women, ETU was also higher in women who washed agricultural work clothes on the day before sampling (11%; 95% CI: 4.9, 17%), women who worked in agriculture during pregnancy (19%; 95% CI: 9.3, 29%), and immigrant women (6.2%; 95% CI: 1.0, 13%). Conclusions: The pregnant women’s urinary ETU concentrations are of concern, and the principal source of exposure is likely to be aerial spraying of mancozeb. The factors predicting ETU provide insight into possibilities for exposure reduction.
Aerial application of mancozeb and urinary ethylene thiourea (ETU) concentrations among pregnant women in Costa Rica: the Infants' Environmental Health Study (ISA).
(Research: Children´s health, 2014-12) van Wendel de Joode, Berna; Mora, Ana María; Córdoba, Leonel; Cano, Camilo; Quesada, Rosario; Faniband, Moosa; Wesseling, Catharina; Ruepert, Clemens; Oberg, Mathias; Eskenazi, Brenda; Mergler, Donna; Lindh, Christian
Background: Mancozeb and its main metabolite ethylene thiourea (ETU) may alter thyroid function; thyroid hormones are essential for fetal brain development. In Costa Rica, mancozeb is aerially sprayed at large-scale banana plantations on a weekly basis. Objectives: Our goals were to evaluate urinary ETU concentrations in pregnant women living near large-scale banana plantations, compare their estimated daily intake (EDI) with established reference doses (RfDs), and identify factors that predict their urinary ETU concentrations. Methods: We enrolled 451 pregnant women from Matina County, Costa Rica, which has large-scale banana production. We visited 445 women up to three times during pregnancy to obtain urine samples (n = 872) and information on factors that possibly influence exposure. We determined urinary ETU concentrations using liquid chromatography mass spectrometry. Results: Pregnant women’s median urinary ETU concentrations were more than five times higher than those reported for other general populations. Seventy-two percent of the women had EDIs above the RfD. Women who lived closest (1st quartile, < 48 m) to banana plantations on average had a 45% (95% CI: 23, 72%) higher urinary ETU compared with women who lived farthest away (4th quartile, ≥ 565 m). Compared with the other women, ETU was also higher in women who washed agricultural work clothes on the day before sampling (11%; 95% CI: 4.9, 17%), women who worked in agriculture during pregnancy (19%; 95% CI: 9.3, 29%), and immigrant women (6.2%; 95% CI: 1.0, 13%). Conclusions: The pregnant women’s urinary ETU concentrations are of concern, and the principal source of exposure is likely to be aerial spraying of mancozeb. The factors predicting ETU provide insight into possibilities for exposure reduction.
Agricoh: A consortium of agricultural cohorts
(Multidisciplinary Digital Publishing Institute(MDPI), Switzerland., 2011-04-29) Leon, Maria; Beane Freeman, Laura; Douwes, Jeroen; Hoppin, Jane; Kromhout, Hans; Lebailly, Pierre; Christian Nordby, Karl; Schenker, Marc; Schüz, Joachim; Waring, Stephen; Alavanja, Michael; Annesi Maesano, Isabella; Baldi, Isabelle; Aqiel Dalvie, Mohamed; Ferro, Giles; Fervers, Beatris; Langseth, Hilde; London, Leslie; Lynch, Charles; McLaughlin, John; Merchant, James; Pahwa, Punam; Sigsgaard, Torben; Stayner, Leslie; Wesseling, Catharina; Keun-Young, Yoo; Zahm, Sheila; Straif, Kurt; Blair, Aaron
AGRICOH is a recently formed consortium of agricultural cohort studies involving 22 cohorts from nine countries in five continents: South Africa (1), Canada (3), Costa Rica (2), USA (6), Republic of Korea (1), New Zealand (2), Denmark (1), France (3) and Norway (3). The aim of AGRICOH, initiated by the US National Cancer Institute (NCI) and coordinated by the International Agency for Research on Cancer (IARC), is to promote and sustain collaboration and pooling of data to investigate the association between a wide range of agricultural exposures and a wide range of health outcomes, with a particular focus on associations that cannot easily be addressed in individual studies because of rare exposures (e.g., use of infrequently applied chemicals) or relatively rare outcomes (e.g., certain types of cancer, neurologic and auto-immune diseases). To facilitate future projects the need for data harmonization of selected variables is required and is underway. Altogether, AGRICOH provides excellent opportunities for studying cancer, respiratory, neurologic, and auto-immune diseases as well as reproductive and allergic disorders, injuries and overall mortality in association with a wide array of exposures, prominent among these the application of pesticides. © 2011 by the authors.
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, Matilde
Habitat 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.
Assessment of dermal exposure to bitumen condensate among road paving and mastic crews with an observational method
(Oxford University Press, 2011-05-19) Agostini, Michela; Wouter, Fransman; De Vocht, Frank; Van Wendel de Joode, Berna; Kromhout, Hans
Objective: To assess dermal exposure to bitumen condensate among road pavers and indoor mastic workers in multiple crews using a semi-quantitative observational method [DeRmal Exposure Assessment Method (DREAM)].Methods: Two skilled observers assessed dermal exposure to bitumen condensate among 85 asphalt workers from 12 crews from nine companies active within four European countries using the DREAM methodology, which produces an estimate of exposure expressed in dimensionless DREAM units. Both observers independently evaluated each crew member's job (N = 14 jobs) for road paving and mastic applications. Potential and actual dermal exposures were estimated for hands and for the rest of the body separately, taking into account the effect of protective clothing. To evaluate the reproducibility of the observational method intra-class correlation coefficients (ICCs) were estimated. The exposures in DREAM units were modelled using linear mixed models to estimate average relative scores for each job. Correlations between dermal exposure parameters were evaluated by estimating Pearson correlation coefficients.Results: A total of 170 observations were completed by two observers independently (n = 118 and n = 52 for 59 road pavers and 26 mastic workers, respectively) in 11 days. The mean ICCs (for potential and actual exposure in DREAM units) varied between 0.74 and 0.80 with values for actual units being slightly higher. Geometric mean potential dermal exposure units of mastic workers were higher than for road pavers (factor 3 for hands and factor 4 for rest of the body). Differences for actual dermal exposure units were smaller for hands (factor 2) and larger for actual exposure units of rest of the body (factor 5). Differences in dermal exposure at the hands between jobs within a paving crew were much larger than between jobs within a mastic crew. Within paving crews, a consistent pattern for all exposure units emerged with 'screed man' and 'raker' as the two highest exposed jobs. Within mastic crews, 'driver dumper truck' and 'spreader of mastic' were scored as the two jobs with the highest exposure units. Potential and actual exposure units were highly correlated. Hands were more profoundly exposed than the rest of the body, with transfer from contaminated surface to the hands as the most important route.Conclusions: DREAM observations were reproducible and showed a consistent dermal exposure pattern among the observed crews. The study provided a clear picture of dermal exposure among road pavers and indoor mastic workers, with the mastic workers being considerably more highly exposed. The most important route of exposure appeared to be transferred from contaminated surfaces to the hands. © The Author 2011.
Assessment of pesticide exposure in the agricultural population of Costa Rica
(British Occupational Hygiene Society, 2005) Monge, Patricia; Partanen, Timo; Wesseling, Catharina; Bravo, Viria; Ruepert, Clemens; Burstyn, Igor
We describe a model for the retrospective assessment of parental exposure to 26 pesticides, selected by toxicity-based prioritization, in a population-based case–control study of childhood leukaemia in Costa Rica (301 cases, 582 controls). The model was applied to a subset of 227 parents who had been employed or self-employed in agriculture or livestock breeding. It combines external data on pesticide use for 14 crops, 21 calendar years and 14 regions, and individual interview data on determinants (task and technology, personal protective equipment, field reentry, storing of pesticides, personal hygiene) of exposure. Recall was enhanced by use of checklists of pesticides in the interview. An external database provided information on the application rate (proxy for intensity of potential exposure) for each pesticide. The calendar time was individually converted to five time windows (year before conception, first, second and third trimester, and first year of the child). Time-windowed individual data on determinants of exposure and their expert-based general weights and their category-specific hazard values jointly provided an individual determinant score. This score was multiplied by the application rate to obtain an individual index of exposure intensity during application. Finally, average exposure intensity during entire time windows was estimated by incorporating in the model the individual time fraction of exposure during application. Estimates of exposure intensities were proxies assumed to be proportional to dermal exposure intensity, which represents the major pathway of occupational exposure to pesticides. A simulated sensitivity analysis resulted in a correlation coefficient of 0.91 between two sets of 10 000 values of individual exposure indices, based on two different but realistic sets expert-assigned weights. Lack of measurement data on concurrent exposures in comparable circumstances precluded direct validation of the model.
Bacterial communities in residential wastewater treatmentplants are physiologically adapted to high concentrations of quaternary ammonium compounds
(Universidad Nacional, Costa Rica, 2023-08-28) Chacón, Luz; Rojas-Jimenez, Keilor; Arias-Andres, Maria
Benzalkoniumchloride(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.
Basic questionnaire and methodological criteria for Surveys on Working Conditions, Employment, and Health in Latin America and the Caribbean
(Cadernos de Saúde Pública, Rio de Janeiro, 2016-09-01) Benavides, Fernando; Merino Salazar, Pamela; Cornelio, Cecilia; Avila Assunção, Ada; Agudelo Suárez, Andrés; Amable, Marcelo; Artazcoz, Lucía; Astete, Jonh; Berhó, Fabián; Carmenate Milián, Lino; Delclòs, George; Funcasta, Lorena; Gerke, Johanna; Gimeno, David; Itatí Iñiguez, María José; Lima, Eduardo de Paula; Martínez Iñigo, David; Medeiros, Adriane Mesquita de; Orta, Lida; Pinilla, Javier; Rodrigo, Fernando; Rojas, Marianela; Sabastizagal, Iselle; Vallebuona, Clelia; Vermeylen, Greet; Villalobos, Gloria; Vives, Alejandra; Barraza, Douglas
El objetivo de este trabajo es presentar un cuestionario básico y criterios metodológicos mínimos, para ser considerados en futuras Encuestas sobre Condiciones de Trabajo, Empleo y Salud (ECTES) en América Latina y el Caribe. Para ello, se llevó a cabo un proceso de consenso, tanto virtual co mo presencial, con la participación de un grupo internacional de expertos que, para definir la propuesta, partieron de las encuestas disponibles en la región hasta 2013. El cuestionario final incluyó 77 preguntas agrupadas en seis dimensiones: características sociodemográficas del trabajador y la empresa; condiciones de empleo; condiciones de trabajo; estado de salud; recursos y actividades preventivas; y características familiares. Entre los criterios metodológicos mínimos destacan el domicilio de la persona en trevistada como lugar de la entrevista y los relacionados con la calidad del trabajo de campo. Estos resultados pueden ayudar a mejorar la compara bilidad de las futuras ECTES en América Latina y el Caribe, lo que contri buiría a mejorar la información en salud laboral en la región
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, Keilor
Bioinformatics 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.
Biomarkers of manganese exposure in pregnant women and children living in an agricultural community in California
(American Chemical Society, 2014) Gunier, Robert; Mora, Ana María; Smith, Donald; Arora, Manish; Austin, Christine; Eskenazi, Brenda; Bradman, Asa
Manganese (Mn) is an essential nutrient but at high exposure levels is a neurotoxicant. There is no wellvalidated biomarker to assess perinatal Mn exposure. A total of 75 mother-child pairs provided blood, urine, and/or deciduous tooth samples. We analyzed Mn in dentin and enamel of shed teeth; maternal, cord, and child blood; and maternal and child urine and examined the interrelationships of Mn levels in all matrices. We observed higher Mn levels in prenatal than postnatal dentin (geometric mean (GM) = 0.51 vs 0.16 Mn:Ca, p < 0.001), maternal blood at delivery than 26 weeks gestation (GM = 20.7 vs. 14.6 μg/L, p = 0.001), and cord blood than child blood at 24 months of age (39.9 vs 25.0 μg/L, p = 0.005). There were no significant correlations between Mn in dentin and Mn concentrations in maternal blood or maternal or child urine. Levels of Mn in prenatal dentin, prenatal maternal blood, and 24 month urine were higher (p < 0.05) among mothers and children living with a farm worker. Prenatal Mn levels in dentin were correlated with Mn loadings and concentrations in prenatal house dust. Levels of Mn measured in tooth dentin constitute a promising biomarker of perinatal exposure.
Blood and hair manganese concentrations in pregnant women from the infants' environmental health study (ISA) in Costa Rica
(American Chemical Society, 2014-03) Mora, Ana María; van Wendel de Joode, Berna; Mergler, Donna; Córdoba, Leonel; Cano, Camilo; Quesada, Rosario; Smith, Donald R; Lindh, Christian H; Bradman, Asa; Eskenazi, Brenda; Menezes-Filho, José A.; Lundh, Thomas
Manganese (Mn), an essential nutrient, is a neurotoxicant at high concentrations. We measured Mn concentrations in repeated blood and hair samples collected from 449 pregnant women living near banana plantations with extensive aerial spraying of Mncontaining fungicide mancozeb in Costa Rica, and examined environmental and lifestyle factors associated with these biomarkers. Mean blood Mn and geometric mean hair Mn concentrations were 24.4 μg/L (8.9−56.3) and 1.8 μg/g (0.05−53.3), respectively. Blood Mn concentrations were positively associated with gestational age at sampling (β = 0.2; 95% CI: 0.1 to 0.2), number of household members (β = 0.4; 95% CI: 0.1 to 0.6), and living in a house made of permeable and difficult-to-clean materials (β = 2.6; 95% CI: 1.3 to 4.0); and inversely related to smoking (β = −3.1; 95% CI: −5.8 to −0.3). Hair Mn concentrations were inversely associated with gestational age at sampling (% change = 0.8; 95% CI: −1.6 to 0.0); and positively associated with living within 50 m of a plantation (% change = 42.1; 95% CI: 14.2 to 76.9) and Mn concentrations in drinking water (% change = 17.5; 95% CI: 12.2 to 22.8). Our findings suggest that pregnant women living near banana plantations aerially sprayed with mancozeb may be environmentally exposed to Mn.
Caesarean delivery and risk of childhood leukaemia: a pooled analysis from the Childhood Leukemia International Consortium (CLIC)
(The Lancet, 2016-04-07) Marcotte, Erin; Thomopoulos, Thomas P; Infante Rivard, Claire; Clavel, Jacqueline; Schuz, Joachim; Ezzat, Sameera; Dockerty, John; Metayer, Catherine; Magnani, Corrado; Scheurer, Michael; Mueller, Beth; Mora, Ana M; Wesseling, Catharina; Skalkidou, Alkistis; Rashed, Wafaa; Francis, Stephen; Ajrouche, Roula; Erdmann, Friederike; Orsi, Laurent; Spector, Logan G
Results from case-control studies have shown an increased risk of acute lymphoblastic leukaemia (ALL) in young children born by caesarean delivery, and prelabour caesarean delivery in particular; however, an association of method of delivery with childhood leukaemia subtypes has yet to be established. We therefore did a pooled analysis of data to investigate the association between childhood leukaemia and caesarean delivery. Methods: We pooled data from 13 case-control studies from the Childhood Leukemia International Consortium done in nine countries (Canada, Costa Rica, Egypt, France, Germany, Greece, Italy, New Zealand, and the USA) for births from 1970-2013. We analysed caesarean delivery overall and by indications that probably resulted in prelabour caesarean delivery or emergency caesarean delivery. We used multivariable logistic regression models, adjusted for child's birthweight, sex, age, ethnic origin, parental education, maternal age, and study, to estimate odds ratios (ORs) and 95% CIs for the risk of ALL and acute myeloid leukaemia (AML) in children aged 0-14 years at diagnosis. Findings: The studies provided data for 8780 ALL cases, 1332 AML cases, and 23 459 controls, of which the birth delivery method was known for 8655 (99%) ALL cases, 1292 (97%) AML cases, and 23 351 (>99%) controls. Indications for caesarean delivery were available in four studies (there were caesarean deliveries for 1061 of 4313 ALL cases, 138 of 664 AML cases, and 1401 of 5884 controls). The OR for all indications of caesarean delivery and ALL was 1Â·06 (95% CI 0Â·99-1Â·13), and was significant for prelabour caesarean delivery and ALL (1Â·23 [1Â·04-1Â·47]; p=0Â·018). Emergency caesarean delivery was not associated with ALL (OR 1Â·02 [95% CI 0Â·81-1Â·30]). AML was not associated with caesarean delivery (all indications OR 0Â·99 [95% CI 0Â·84-1Â·17]; prelabour caesarean delivery 0Â·83 [0Â·54-1Â·26]; and emergency caesarean delivery 1Â·05 [0Â·63-1Â·77]). Interpretation: Our results suggest an increased risk of childhood ALL after prelabour caesarean delivery. If this association is causal, maladaptive immune activation due to an absence of stress response before birth in children born by prelabour caesarean delivery could be considered as a potential mechanism. Funding: National Cancer Institute. Â© 2016 Elsevier Ltd.
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 González, Denis Mauricio
El cultivo de palma aceitera muestra un acelerado crecimiento a nivel mundial. Según datos oficia-les, 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 tro-picales 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 agro-pecuarias 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.
Can a mixture of agrochemicals (glyphosate, chlorpyrifos and chlorothalonil) mask the perception of an individual chemical? A hidden trap underlying ecological risk
(Elsevier, 2022-01) Mena, Freylan; Romero, Adarli; Blasco, Julián; Araújo, Cristiano VM
As aquatic environments associated with conventional agriculture are exposed to various pesticides, it is important to identify any possible interactions that modify their effects when in a mixture. We applied avoidance tests with Danio rerio, exposing juveniles to three relevant current use pesticides: chlorpyrifos (CPF), chlorothalonil (CTL) and glyphosate (Gly), individually and in binary mixtures (CPF-Gly and CTL-Gly). Our goal was to identify the potential of contaminants to trigger the avoidance response in fish and detect any changes to that response resulting from binary mixtures. Avoidance was assessed for three hours using an open gradient system with six levels of increasing concentrations. Fish avoided environmentally relevant concentrations of the three compounds. The avoidance of CPF [AC50 = 7.95 (3.3–36.3) μg/L] and CTL [AC50 = 3.41 (1.2–41.6) μg/L] was evident during the entire period of observation. In the case of Gly, the response changed throughout the experiment: initially (until 100 min) the fish tolerated higher concentrations of the herbicide [AC50 = 52.2 (12.1–2700) μg/L] while during the later period (after 100 min) a clearer avoidance [1.5 (0.8–4.2) μg/L] was observed. The avoidance recorded using CPF and CTL alone was attenuated by the presence of Gly. Applying an additive concentration model, Gly initially acted synergistically with the other two compounds, although this interaction was not observed during the later period. Avoidance gives us an idea of how the distribution of populations may be altered by contamination, our results suggest that in some mixtures this response may be inhibited, at least temporarily, thus masking the ecological risk of the exposure.

Examinar

Examinando Artículos científicos por Título