Artículos científicos

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Cancer of the Brain and Nervous System and Occupational Exposures in Finnish Women
(Universidad Nacional, Costa Rica, 2002-07) Wesseling, Catharina; Pukkala, Eero; Neuvonen, Kaisa; Kauppinen, Timo; Boffetta, Paolo; Partanen, Timo
Occupational agents were evaluated for the risk of brain-nervous system cancer in a cohort of 413,877 Finnish women with blue-collar occupations in 1970. Observed and expected numbers of incident cases and the intensities of exposure to 25 agents were generated for 183 job titles from 1971 to 1995. Poisson regression models linked incidence and exposure data. Increased risks were found for medium/high intensities of iron (standardized incidence ratio [SIR], 2.15; 95% confidence interval [CI], 0.96 to 4.80), oil mist (1.95; 0.97 to 3.90), any chromium compounds (1.51; 0.85 to 2.67), electromagnetic fields (1.37; 0.98 to 2.10), aliphatic and alicyclic hydrocarbon compounds (1.34; 0.80 to 2.27), lead (1.27; 0.81 to 2.01), cadmium (1.26; 0.72 to 2.22), and aromatic hydrocarbon compounds (1.20; 0.71 to 2.03). Strengths of the study include fair number of cases, virtually complete case coverage, and a high-quality job exposure matrix. Ecological design and cross-sectional job assessment introduced exposure misclassification and tended to drive risk estimates toward unity.
Central nervous system effects of acute organophosphate poisoning in a two-year follow-u
(Universidad Nacional, Costa Rica, 2004) Delgado, Edgar; McConnell, Rob; Miranda, Jamilette; Keifer, Matthew; Lundberg, Ingvar; Partanen, Timo; Wesseling, Catharina
Objectives. Patients hospitalized for acute organophosphate poisoning in León, Nicaragua, were followed for effects on the central nervous system (CNS) over a 2-year period. Methods. Immediate verbal memory (Rey verbal learning), visuomotor performance (digit symbol), and neuropsychiatric symptoms (Q-16) were assessed for 53 poisoned persons at the time of hospital discharge, 7 weeks postpoisoning, and 2 years postpoisoning, and, at the same time intervals, for 28 persons who had never been poisoned. The poisonings were classified as moderate occupational (31), severe occupational (15), and severe through the oral route (7), representing low, medium, and high exposure, respectively. Longitudinal confounder-adjusted between-category comparisons and longitudinal analyses of variance and covariance were used to assess the effects of the exposure. Results. Immediate verbal learning showed deficits in the high-exposure group, in particular at the time of discharge, but the estimate of the difference when compared with the values of the unexposed was imprecise. Visuomotor performance showed a deficit at 7 weeks in the medium-exposure group, but it had improved after 2 years relative to that of the unexposed, for whom improvement had occurred at 7 weeks and persisted during the 2 years of follow-up, possibly a test-retest effect. Neuropsychiatric symptoms were in excess 2 years after the hospital discharge in the low- and medium-exposure groups and all the groups combined. All the results were imprecise for the small high-exposure group. Conclusions. Visuomotor performance and possibly short-term verbal memory seem to be affected early after severe acute organophosphate poisoning and recover, either truly or by some compensatory mechanism. Neuropsychiatric symptoms seem to increase after a longer latency period
Current-use pesticide transport to Costa Rica's high-altitude tropical cloud forest
(Environmental Toxicology and Chemistry, 2011-12) Shunthirasingham, Chubashini; Gouin, Todd; Lei, Ying D.; Ruepert, Clemens; Castillo, Luisa E; Wania, Frank
To gain insight into the atmospheric transport and deposition of organic contaminants in high-altitude forests in the humid tropics, pesticides were analyzed in air, water, and soil samples from Costa Rica. Passive samplers deployed across the country revealed annually averaged air concentrations of chlorothalonil, endosulfan, and pendimethalin that were higher in areas with intensive agricultural activities than in more remote areas. Atmospheric concentrations were particularly high in the intensively cultivated central valley. Only endosulfan and its degradation products were found in soils sampled along an altitudinal transect on the northern side of Volcano Turrialba, which is facing heavily cultivated coastal plains. Consistent with calculations of cold trapping in tropical mountains, concentrations of endosulfan sulfate increased with altitude. Pesticide levels in lake, creek, fog, and arboreal water samples from high-elevation cloud forests were generally below 10 ng L 1. Endosulfan sulfate was the most abundant pesticide in water, with concentrations ranging from 0.4 to 9.4 ng L 1. Its levels were highest in water sampled from bromeliads. Levels of total endosulfan in water are much lower than the reported median lethal concentration (LC50) value for acute toxicity of a-endosulfan to tadpoles. Although this suggests that the presence of pesticide might not have a direct impact on amphibian populations, the possibility of effects of chronic exposure to a mixture of substances cannot be excluded. Fog was relatively enriched in some of the analyzed pesticides, such as dacthal and chlorothalonil, and may constitute an important deposition pathway to high-altitude tropical cloud forest.
Chronic nervous-system effects of long-term occupational exposure to DDT
(Universidad Nacional, Costa Rica, 2001) Van Wendel, De Joode; Wesseling, , C; Kromhout, H; Monge, P; Garcia, M; Mergler, D
Dichlorodiphenyltrichloroethane (DDT) is a compound with moderate toxicity that is judged to be safe for occupational use, although little is known about its long-term effects on the human nervous system. We investigated chronic nervous-system effects of long-term occupational exposure to DDT by comparing the neurobehavioural performance of retired malaria-control workers with a reference group of retired guards and drivers. DDT-exposed workers did worse on tests assessing various neurobehavioural functions than controls; performance significantly deteriorated with increasing years of DDT application. Our results could not be explained by exposure to cholinesterase-inhibiting pesticides or other potential confounding factors.
CAREX Nicaragua and Panama: Worker exposures to carcinogenic substances and pesticides
(Universidad Nacional, Costa Rica, 2011) BLANCO ROMERO, LUIS ENRIQUE; VEGA, LUIS; LOZANO CHAVARRÍA, LUZ; PARTANEN, TIMO
This study provides data on numbers of workers exposed at work to selected carcinogens and pesticides in Nicaragua (35 substances) and Panama (31), based on a modification of the CAREX data system. Population censuses provided industry- and sex-specific work-force numbers. The activity- and sex-specific proportions of exposed workers were estimated by experts from governmental agencies, workers' organizations, and employers' representatives. Finally, the numbers of those occupied in each activity/sex category were multiplied by the proportions of those exposed in the same categories, yielding numbers of those exposed in these categories for each agent. The study revealed high proportions (> 9%) of occupationally exposed workers in both countries for solar radiation and diesel engine emissions; environmental tobacco smoke in Panama; and some pesticides in Nicaragua. A high proportion of exposed was found for men for lead (12%), silica dust (10%), and hexavalent chromium (10%) in Panama.
Tetracycline and 4-epitetracycline modified the in vitro catabolic activity and structure of a sediment microbial community from a tropical tilapia farm idiosyncratically
(Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes, 2013-05-05) Granados, Fabio; Arias-Andrés, María; Rodríguez, César
Aquaculture farmers commonly add tetracycline to fish feed or to their ponds to prevent or treat bacterial infections in their crops. To assess the short-term effect of tetracycline (TET) and of one of its reversible epimers, 4-epitetracycline (ETC), on the function and structure of a sediment microbial community from a tropical tilapia farm, we contrasted community-level physiological profiles (CLPP) and phospholipid fatty acid profiles (PLFA) obtained from microcosms exposed for 12 days to 5, 10, 50, or 75 mg kg-1of these antibiotics. Notwithstanding that the concentration of the antibiotics during the experiment decreased between 13-100% (TET) or 16-61% (ETC), both compounds provoked opposing metabolic responses that did not revert. TET displayed a tendency to inhibit respiration at concentrations < 50 mg kg-1, whereas ETC showed the opposite effect. As revealed by the finding of the fatty acids 11:0 iso 3OH, 16:1w6c, and 18:1w6c, the sediment analyzed was predominantly colonized by Gram-negative bacteria. A marked decrease in fatty acid diversity accompanied the aforementioned metabolic responses, with TET concentrations > 50 mg kg-1leading to an enrichment of yeast and fungal biomarkers and both antibiotics at concentrations < 10 mg kg-1selecting for microorganisms with 11:0 iso 3OH. In agreement with CLPP data, differences between the PLFA profiles of control and treated microcosms were more pronounced for TET than for ETC. We conclude that high, yet field-relevant, concentrations of TET and ETC have the potential to modify the composition, and to a lesser extent, the functioning of a sediment microbial community. This study highlights the importance of considering antibiotic degradation products in ecotoxicological research.
Associations of sickness absence for pain in the low back, neck and shoulders with wider propensity to pain
(BMJ Publishing Group, 2020-05-01) Coggon, David; Ntani, Georgia; Walker-Bone, Karen; Felli, Vanda E.; Harar, Raul; Barrero, Lope H.; Felknor, Sarah A.; Rojas, Marianela; Cattrell, Anna; Serra, Consol; Bonzini, Matteo; Solidak, Eleni; Merisalu, Eda; Habib, Rima R.; Sadeghian, Farideh; Kadir, M. Masood; Wickremasinghe, A. Rajitha; Matsudaira, Ko; Nyantumbu Mkhize, Busisiwe; Kelsall, Helen L.; Harcombe, Helen
Objectives To explore the association of sickness absence ascribed to pain at specific anatomical sites with wider propensity to musculoskeletal pain. Methods As part of the CUPID (Cultural and Psychosocial Influences on Disability) study, potential risk factors for sickness absence from musculoskeletal pain were determined for 11 922 participants from 45 occupational groups in 18 countries. After approximately 14 months, 9119 (78%) provided follow-up information about sickness in the past month because of musculoskeletal pain, including 8610 who were still in the same job. Associations with absence for pain at specific anatomical sites were assessed by logistic regression and summarised by ORs with 95% CIs. Results 861 participants (10%) reported absence from work because of musculoskeletal pain during the month before follow-up. After allowance for potential confounders, risk of absence ascribed entirely to low back pain (n=235) increased with the number of anatomical sites other than low back that had been reported as painful in the year before baseline (ORs 1.6 to 1.7 for ≥4 vs 0 painful sites). Similarly, associations with wider propensity to pain were observed for absence attributed entirely to pain in the neck (ORs up to 2.0) and shoulders (ORs up to 3.4). Conclusions Sickness absence for pain at specific anatomical sites is importantly associated with wider propensity to pain, the determinants of which extend beyond established risk factors such as somatising tendency and low mood. Better understanding of why some individuals are generally more prone to musculoskeletal pain might point to useful opportunities for prevention.
Monitoring Pesticide Use and Associated Health Hazards in Central America
(Universidad Nacional, Costa Rica., 2011) Bravo, Viria; Rodríguez, Teresa; Van Wendel de Joode, Berna; Canto, Nonato; Calderón, Gloria Ruth; Turcios, Miguel; Menéndez, Luis Armando; Mejía, Winston; Tatis, Anabel; Abrego, Federico Z.; De la Cruz, Elba; Wesseling, Catharina
We established methods for monitoring pesticide use and associated health hazards in Central America. With import data from Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama for 2000-2004, we constructed quantitative indicators (kg active ingredient) for general pesticide use, associated health hazards, and compliance with international regulations. Central America imported 33 million kg active ingredient per year. Imports increased 33% during 2000-2004. Of 403 pesticides, 13 comprised 77% of the total pesticides imported. High volumes of hazardous pesticides are used; 22% highly/extremely acutely toxic, 33% moderately/severely irritant or sensitizing, and 30% had multiple chronic toxicities. Of the 41 pesticides included in the Stockholm Convention on Persistent Organic Pollutants (POPs), the Rotterdam Convention on Prior Informed Consent (PIC), the Montreal Protocol on Substances that Deplete the Ozone Layer, the Pesticide Action Network (PAN) Dirty Dozen, and the Central American Dirty Dozen, 16 (17% total volume) were imported, four being among the 13 most imported pesticides. Costa Rica is by far the biggest consumer. Pesticide import data are good indicators of use trends and an informative source to monitor hazards and, potentially, the effectiveness of interventions.
Social Conditions and Urban Health Inequities: Realities, Challenges and Opportunities to Transform the Urban Landscape through Research and Action
(Journal of Urban Health, 2011-12) Salgado de Snyder, V. Nelly; Friel, Sharon; Fotso, Jean Christophe; Khadr, Zeinab; Meresman, Sergio; Monge, Patricia; Patil-Deshmukh, Anita
The process of urbanization entails social improvements with the consequential better quality-of-life for urban residents. However, in many low-income and some middle-income countries, urbanization conveys inequality and exclusion, creating cities and dwellings characterized by poverty, overcrowded conditions, poor housing, severe pollution, and absence of basic services such as water and sanitation. Slums in large cities often have an absence of schools, transportation, health centers, recreational facilities, and other such amenities. Additionally, the persistence of certain conditions, such as poverty, ethnic heterogeneity, and high population turnover, contributes to a lowered ability of individuals and communities to control crime, vandalism, and violence. The social vulnerability in health is not a “natural” or predefined condition but occurs because of the unequal social context that surrounds the daily life of the disadvantaged, and often, socially excluded groups. Social exclusion of individuals and groups is a major threat to development, whether to the community social cohesion and economic prosperity or to the individual self-realization through lack of recognition and acceptance, powerlessness, economic vulnerability, ill health, diminished life experiences, and limited life prospects. In contrast, social inclusion is seen to be vital to the material, psychosocial, and political aspects of empowerment that underpin social well-being and equitable health. Successful experiences of cooperation and networking between slum-based organizations, grassroots groups, local and international NGOs, and city government are important mechanisms that can be replicated in urban settings of different low- and middle-income countries. With increasing urbanization, it is imperative to design health programs for the urban poor that take full advantage of the social resources and resourcefulness of their own communities.
Accuracy and reliability of buccal bone height and thickness measurements from cone-beam computed tomography imaging
(Universidad Nacional, Costa Rica, 2011-06) Covell, , David; Benninger, Brion; Crowe, Jennifer; Michael, Leo; MacDonald, Terry; Cook, Valane; Timock, Adam
Cone-beam computed tomography (CBCT) imaging has broadened opportunities for examining morphologic aspects of the craniofacial complex, including alveolar bone, but limitations of the technology have yet to be defined. Through the use of comparisons with direct measurements, the purpose of this study was to investigate the accuracy and reliability of buccal alveolar bone height and thickness measurements derived from CBCT images. Twelve embalmed cadaver heads (5 female, 7 male; mean age: 77 years) were scanned with an i-CAT 17-19 unit (Imaging Sciences International, Hatfield, Pa) at 0.3 mm voxel size. Buccal alveolar bone height and thickness measurements of 65 teeth were made in standardized radiographic slices and compared with direct measurements made by dissection. All measurements were repeated 3 times by 2 in dependent raters and examined for intrarater and interrater reliability. Measurement means were compared with 2-tailed t tests. Agreement between direct and CBCT measurements was assessed by concordance correlation coefficients, Pearson correlation coefficients, and Bland-Altman plots. Intrarater reliability was high as were interrater correlations for all measurements ($0.97) except CBCT buccal bone thickness (0.90). CBCT measurements did not differ significantly from direct measurements, and there was no pattern of underestima tion or overestimation. The mean absolute differences were 0.30 mm in buccal bone height and 0.13 mm in buc cal bone thickness with 95% limits of agreement of 0.77 to 0.81 mm, and 0.32 to 0.38 mm, respectively. Agreement between the 2 methods was higher for the measurements of buccal bone height than buccal bone thickness, as demonstrated by concordance correlation coefficients of 0.98 and 0.86, respectively. Conclusions: For the protocol used in this study, CBCT can be used to quantitatively assess buccal bone height and buccal bone thickness with high precision and accuracy. Comparing the 2 sets of CBCT measurements, buccal bone height had greater reliability and agreement with direct measurements than did the buccal bone thickness measurements. (Am J Orthod Dentofacial Orthop 2011;140:734-44
Assessment of long-term and recent pesticide exposure among rural school children in Nicaragua
(Occupational and Environmental Medicine, 2012-02) Rodríguez, Teresa; van Wendel de Joode, Berna; Lindh, Christian; Rojas, Marianela; Lundberg, Ingvar; Wesseling, Catharina
This study assessed pesticide exposure of children in rural Nicaragua in relation to parental pesticide use, from around conception to current school age, as part of an epidemiological evaluation of neurodevelopment effects. Methods: We included 132 children whose parents were subsistence farmers or plantation workers, or had an agricultural history. As proxies for children's long-term exposures, we constructed cumulative parental pesticide-specific use indices for periods before and after the child's birth from data obtained using an icon-calendar-based questionnaire, of application hours (h) for plantation workers and subsistence farmers, and of kilograms of active ingredients (ai) only for subsistence farmers. Pesticide residues of TCPY, 3-PBA and 2,4-D were analysed in children's urine as indicators for current exposures. Results: Life-time indices were highest for the organophosphates chlorpyrifos (median 114 h (min 2; max 1584), 19.2 kg ai (min 0.37; max 548)) and methamidophos (84 h (6; 1964), 12.2 kg ai (0.30; 780)). The P50 values of children's urinary residues were 3.7 μg/g creatinine for TCPY, 2.8 for 3-PBA and 0.9 for 2,4-D; TCPY values are comparable with those in other countries, but 3-PBA and 2,4-D are considerably higher. The maximum levels for all three pesticides are the highest reported for children. Residues increased on days after application, but most high residue levels were unrelated to parental pesticide applications. Conclusion: Urinary pesticide residues reveal high environmental exposure among children in rural Nicaragua. The quantitative parental pesticide use indices as proxies for children's exposures during different periods may be useful for the evaluation of developmental health effects.
Cancer in Banana Plantation Workers in Costa Rica
(Universidad Nacional, Costa Rica, 1996) WESSELING, CATHARINA; Ahlbom, Anders; Antich, Daniel; Rodríguez, Ana Cecilia; Castro, Roberto
Background. Costa Rica has population and disease registries with potential value for epidemiological research. Pesticides have been intensively used on banana plantations, for example dibromochloropropane (DBCP). This study was planned to examine the quality of the cancer and civil registries and the feasibility of record linkages, and to explore cancer patterns among a highly exposed group. Methods. A retrospective cohort study was carried out. Workers on the payrolls of banana companies, as reported to the Social Security System at any time between 1972 and 1979, were followed up in the cancer registry between 1981 and 1992: 29,565 men and 4892 women for 407,468 person-years. The observed cases of cancer were compared to the expected values, derived from the national incidence rates. Results. We identified 368 cancer cases, 292 among men (standardized incidence ratio [SIR] = 76, 95% confidence interval [CI] 67-84) and 76 among women (SIR = 116, 95% CI: 90-142). Among men increased SIR were observed for melanoma (SIR = 197, 95% CI: 94-362) and penile cancer (SIR = 149, 95% CI: 55-324); among women for cervix cancer (SIR = 182, 95% CI: 122-241) and leukaemia (SIR = 274, 95% CI: 86-639). Risk estimates for lung cancer were elevated among male workers with the longest time of employment. Conclusions. Follow-up was difficult due to deficient identification variables in the cancer registry and to easier identification of the living compared to the deceased in the civil registry at the end of the observation period. The various systematic errors in this study are likely to produce an underestimation of the relative risk estimates. This study contributes to improvements of the registries and increases the potential for cancer epidemiology in Costa Rica and other developing countries.
Parental age and the risk of childhood acute myeloid leukemia: results from the Childhood Leukemia International Consortium
(Elsevier Ltd, 2019-04) Panagopoulou, Paraskevi; Auvinen, Anssi; Spector, Logan; Roman, Eve; Pombo-de-Oliveira, Maria; Scheurer, Michael; Mora, Ana Maria; Doody, David; Kane, Eleanor; Ntzani, Evangelia; Martínez Rodríguez, Elenita
Parental age has been associated with several childhood cancers, albeit the evidence is still inconsistent. To examine the associations of parental age at birth with acute myeloid leukemia (AML) among children aged 0–14 years using individual-level data from the Childhood Leukemia International Consortium (CLIC) and non-CLIC studies. We analyzed data of 3182 incident AML cases and 8377 controls from 17 studies [seven registry-based case-control (RCC) studies and ten questionnaire-based case-control (QCC) studies]. AML risk in association with parental age was calculated using multiple logistic regression, meta-analyses, and pooled-effect estimates. Models were stratified by age at diagnosis (infants < 1 year-old vs. children 1–14 years-old) and by study design, using five-year parental age increments and controlling for sex, ethnicity, birthweight, prematurity, multiple gestation, birth order, maternal smoking and education, age at diagnosis (cases aged 1–14 years), and recruitment time period. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) derived from RCC, but not from the QCC, studies showed a higher AML risk for infants of mothers ≥40-year-old (OR = 6.87; 95% CI: 2.12–22.25). There were no associations observed between any other maternal or paternal age group and AML risk for children older than one year. An increased risk of infant AML with advanced maternal age was found using data from RCC, but not from QCC studies; no parental age-AML associations were observed for older children.
Manganese exposure and working memory-related brain activity in smallholder farmworkers in Costa Rica: Results from a pilot study
(Academic Press Inc., 2019-04-06) Rojas Valverde, Daniel; Gutierrez Vargas, Randall; Fuhrimann, Samuel; Menezes Filho, José; Mora, Ana Maria; Palzes, Vanessa; Sagiv, Sharon; Baker, Joseph; Winkler, Mirko; Staudacher, Philipp; Reiss, Allan; Eskenazi, Brenda
Main sources of manganese (Mn) in the general population are diet and drinking water. Mn is also found in ethylene bisdithiocarbamate (EBDC) fungicides used in agriculture or emitted into the air by ferromanganese plants and welding fumes, which can be additional environmental and occupational sources of exposure. High occupational Mn exposure has been linked with motor, behavioral, and cognitive impairment, but its effects on neural function remain poorly understood. We conducted a functional neuroimaging study in a sample of 48 farmworkers in Zarcero County, Costa Rica, an agricultural region where EBDC fungicides are sprayed. We measured Mn concentrations in farmworkers’ toenails (n = 40 farmworkers) and hair (n = 33 farmworkers), and recorded brain activity in the dorsolateral prefrontal cortex during a letter-retrieval working memory task using functional near-infrared spectroscopy (fNIRS). We estimated exposure-outcome associations using multivariable linear egression models adjusted for age and education level. Geometric mean (geometric standard deviation) toenail and hair Mn concentrations were 0.40 μg/g (3.52) and 0.24 μg/g (3.54), respectively. We did not find strong evidence that Mn concentrations were associated with working memory-related brain activity in this sample of farmworkers; we also found null associations between working memory task accuracy and brain activity. However, our small sample size may have limited our ability to detect small effect sizes with statistical precision. Our study demonstrates that fNIRS can be a useful and feasible tool in environmental epidemiology for examining the effects of toxicants, like Mn, on neural function. This may prove to be important for elucidating neuropathological pathways that underlie previously reported ssociations of elevated Mn exposure with neurotoxic effects.
Prenatal Exposure to Mixtures of Phthalates, Parabens, and Other Phenols and Obesity in Five-Year-Olds in the CHAMACOS Cohort
(International Journal of Environmental Research and Public Health, 2021-02-12) Berger, Kimberly; Hyland, Carly; Ames, Jennifer; Mora, Ana Maria; Huen, Karen; Eskenazi, Brenda; Holland, Nina; Harley, Kim
Exposures to phthalates, parabens, and other phenols are often correlated due to their ubiquitous use in personal care products and plastics. Examining these compounds as a complex mixture may clarify inconsistent relationships between individual chemicals and childhood adiposity. Using data from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study, a longitudinal cohort of children in Salinas Valley, California (n = 309), we examined biomarkers of 11 phthalate metabolites and 9 phenols, including several parabens and bisphenol A, measured in maternal urine at two time points during pregnancy. We measured child height and weight at age five to calculate the body mass index (BMI) z-scores and overweight/obesity status. The association between prenatal urinary concentrations of biomarkers with the childhood BMI z-score and overweight/obesity status was analyzed using single-pollutant models and two mixture methods: Bayesian hierarchical modeling (BMH) and Bayesian kernel machine regression (BKMR). Urinary concentrations of monoethyl phthalate, monocarboxy-isononly phthalate (metabolites of diethyl phthalate and di-isodecyl phthalate, respectively), and propylparaben were consistently associated with an increased BMI z-score and overweight/obesity status across all modeling approaches. Higher prenatal exposures to the cumulative biomarker mixture also trended with greater childhood adiposity. These results, robust across two methods that control for co-pollutant confounding, suggest that prenatal exposure to certain phthalates and parabens may increase the risk for obesity in early childhood.
Agricultura expansiva potencia el uso de plaguicidas
(Universidad Nacional, Costa Rica, 2014-09) Ortiz, Laura
En los últimos años, cultivos como piña, caña de azúcar, arroz y palma africana han aumentado sus áreas de producción en distintas zonas del país, y otros como banano, café y cítricos se han mantenido en grandes extensiones; con ello, Costa Rica se convierte en uno de los países con mayor índice de importación de plaguicidas por habitante y por área agrícola.
Sustancias biocidas en la producción de caña de azúcar en Costa Rica
(2022) Ramírez, Fernando; Bravo, Vyria; Herrera, Gustavo; Cruz Malavassi, Elba de la
La cantidad de plaguicidas importados en Costa Rica aumentó de 8.400 a 13.300 ton ia entre 2000 y 2012 (58%), asociado a un crecimiento del área agrícola del 10%. El cultivo de caña de azúcar pasó de 47.200 a 57.600 ha (22%). Las principales zonas productoras son Pacífico Seco, Pacífico Central, Región Norte, Valle Central Occidental y Oriental, y Región Sur; Guanacaste concentra más del 50% del área.
Uso del herbicida glifosato en Costa Rica en el periodo 2007 a 2015
(Universidad Nacional, Costa Rica, 2017-01-30) Ramírez Muñoz, Fernando; Bravo Durán, Virya; Herrera Ledezma, Gustavo
Costa Rica es uno de los mayores importadores y usuarios de plaguicidas a nivel centroamericano. El glifosato es el herbicida de mayor uso, tanto en el mundo como en Costa Rica. Se utiliza en la mayoría de cultivos: anuales, perennes y en zonas no agrícolas. Por medio de entrevistas a sujetos productores agrícolas se conocieron las cantidades usadas de glifosato en los principales cultivos. Las importaciones de este herbicida se iniciaron en 1982 con 36 toneladas de ingrediente activo (T i.a.), y se llegó a importar 1 761 T i.a. en 2013. Se calculó el uso ponderado de glifosato en kg i.a./ ha/ciclo. Los cultivos perennes son los principales consumidores de glifosato (51,6% del total), le siguen las zonas no agrícolas (37,1%) y los cultivos anuales (10,8%), la mayoría granos como arroz, frijol y maíz. Por cultivo, la palma africana consume el 24,9% del total de glifosato usado en el país, le sigue el arroz (7,8%), café (5,4%), banano (5,2%), cítricos (4,6%) y pastos (3,7%). En cultivos como el pejibaye para palmito, se nota una dependencia de este herbicida en el manejo de malezas, lo que ha llevado a que poblaciones de malezas evolucionen en resistencia.
Habitat preferences and simulation of physical habitat availability of Perlidae (Plecoptera) and Corydalidae (Megaloptera) in a neotropical river
(Editorial UCR, 2025-11-03) Quesada Alvarado, Francisco; Echeverría Sáenz, Silvia; Chaves Quirós, Anny
Habitat preferences represent the distribution and abundance of species among different habitat types. These preferences are highly relevant ecological information because they relate to the feeding strategies, offspring care and predator avoidance refuges of the organisms, therefore potentially influencing their fitness. To define the habitat preference of the nymphs of Anacroneuria spp. (Plecoptera) and larvae of Corydalus spp. (Megaloptera) with respect to current velocity and depth. Methods: We evaluated the abundance of Anacroneuria and Corydalus with information gathered through 15 field campaigns in three sites of the Savegre River, Costa Rica. Also, we used habitat preferences to create simulations of the physical habitat availability for these species through hydraulic models to determine habitat gain or loss due to variations in flow. Anacroneuria (Plecoptera) nymphs preferred velocities of 0.9 m/s and depths between 23-36 cm, while Corydalus (Megaloptera) larvae preferred velocities between 0.6-0.8 m/s, and depths between 17-29 cm. As a case study, these preferences were modeled to determine optimal, regular or inadequate habitat availability for Anacroneuria and Corydalus given hypothetical flow variations in the Savegre River (Costa Rica). A discharge of < 8 m3/s resulted in a decrease in optimal habitat, mainly because it decreased water velocity below the preferred ranges. Also, a discharge of > 18 m3/s resulted in a decrease in optimal habitat because of the depth increase. This type of information is scarce or even absent for neotropical rivers, though necessary for a description of a healthy habitat. Furthermore, this habitat preference vs. modeled habitat availability approach is highly useful, -both in tropical and temperate rivers- for understanding the potential effects of any water derivation or exploitation.
Taller sobre agricultura y sector informal: SALTRA promueve la capacitación en salud ambiental en 6 países de Centroamérica
(SALTRA, 2014-04) Rojas Garbanzo, Marianela; Víquez Zamora, Diana

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