Seroprevalence of the SARS-CoV-2 antibody in healthcare workers: a multicentre cross-sectional study in 10 Colombian cities.

BACKGROUND: Healthcare workers are at increased risk of infection due to occupational exposure to SARS-CoV-2-infected patients. The objective of this study was to determine the seroprevalence of SARS-CoV-2 in healthcare workers in Colombia. METHODS: This study is a cross-sectional study focused on estimating the seroprevalence of SARS-CoV-2 antibodies in healthcare workers from 65 hospitals in 10 cities in Colombia during the second semester of 2020. The seroprevalence was determined using an automated immunoassay (Abbott SARS-CoV-2 CLIA IgG). The study included a survey to establish the sociodemographic variables and the risk of infection. A multivariate model was used to evaluate the association between the results of seroprevalence and risk factors. RESULTS: The global seroprevalence of antibodies against SARS-CoV-2 was 35% (95% Bayesian CI 33% to 37%). All the personnel reported the use of protective equipment. General services personnel and nurses presented the highest ratios of seroprevalence among the healthcare workers. Low socioeconomic strata have shown a strong association with seropositivity. CONCLUSION: This study estimates the prevalence of SARS-CoV-2 infection among healthcare workers. Even though all the personnel reported the use of protective equipment, the seroprevalence in the general services personnel and nurses was high. Also, a significant difference by cities was observed.

Chronic pesticide mixture exposure including paraquat and respiratory outcomes among Colombian farmers.

This study explored the potential association between chronic exposure to pesticide mixtures including paraquat and respiratory outcomes among Colombian farmers. Sociodemographic and occupational data, respiratory symptoms and spirometric data were collected. Paraquat in spot urine samples were quantified with solid-phase extraction high-performance liquid chromatography. Multiple Poisson regressions with robust variance were used to determine factors associated with respiratory outcomes. Profiles of pesticide mixtures used were identified among 217 farmworkers, but profenofos and methamidophos-based mixtures were more frequent. Chronic paraquat exposure was slightly associated with self-reported asthma (PR: 1.06; 95% CI 1.00 to 1.13). Different pesticide mixtures were associated with flu, thoracic pain, allergic rhinitis, and obstructive pattern in spirometry. Although acute exposure to paraquat is low among Colombian farmers participating in the study, associations between respiratory outcomes and chronic pesticide mixtures exposure including profenofos, methamidophos or glyphosate require further specific studies.

Evaluación de la exposición al polvo de carbón y de sílice en sitios de minería subterránea en tres departamentos de Colombia / Evaluation of the exposure to coal dust and prevalence of pneumoconiosis in underground mining in three Colombian departments

Introducción. La neumoconiosis de mineros del carbón es una enfermedad crónica e irreversible que se considera un problema de salud pública. Objetivo. Estimar la prevalencia de neumoconiosis y sus factores asociados en mineros de carbón de Boyacá, Cundinamarca y Norte de Santander. Materiales y métodos. Se hizo un estudio de corte transversal en 476 mineros. Se les hizo valoración médica, se tomaron radiografías de tórax siguiendo los criterios de la Organización Internacional del Trabajo, así como espirometrías, y se identificaron los polimorfismos de la glutatión S-transferasa y de las enzimas de reparación. Las asociaciones entre las condiciones ocupacionales y de la empresa con la neumoconiosis, se estudiaron usando modelos de regresión de Cox. Resultados. En 31 empresas se hicieron 479 monitorizaciones ambientales y se evaluaron 476 trabajadores cuyo tiempo de trabajo fluctuaba entre 10 y 57 años. La prevalencia de la neumoconiosis fue de 33,8 % (IC95% 27,0-41,3). En el modelo de regresión multivariado de Cox, con tiempo de riesgo constante para la neumoconiosis, esta se asoció significativamente con el trabajo en empresas medianas (razón de prevalencias, RP=2,00; IC95% 0,995- 2,690; p=0,052), con un nivel alto de exposición al polvo de carbón según el índice de exposición (RP=2,055; IC95% 1,043-4,048; p=0,038), y una antigüedad de 25 años o más (para 25,0 a 29,9 años: RP=2,199; IC95% 1,449-3,338; p=0,001). Conclusiones. La prevalencia de la neumoconiosis fue muy alta y se asoció a la exposición a altos niveles de polvo de carbón, a una exposición laboral mayor o igual a 25 años y al trabajo en empresas medianas.

Introduction: Coal workers' pneumoconiosis is a chronic and irreversible disease representing a public health problem. Objective: To estimate the prevalence of pneumoconiosis and its associated factors among underground coal miners in the Colombian departments of Boyacá, Cundinamarca and Norte de Santander. Materials and methods: We conducted a cross-sectional study of 476 miners to measure the prevalence of pneumoconiosis and its associated factors such as coal dust and silica levels, as well as the occupational conditions. The medical assessment and a chest x-ray were performed according to the International Labor Organization criteria, along with spirometry and the identification of glutathione S-transferase and repair enzyme polymorphisms. The associations were explored using Cox regression models. Results: We performed a total of 479 environmental monitoring sessions in 31 companies and we evaluated 476 workers with 10 to 57 years of mining work experience. The prevalence of pneumoconiosis was 33.8% (95% CI: 27.0 - 41.3%). In the Cox multivariate regression model with a constant risk time, pneumoconiosis was significantly associated with working in medium-sized companies (PR=2.00, 95% CI: 0.995 - 2.690; p=0.052), the level of severe exposure to coal dust (PR=2.055, 95% CI: 1.043 - 4.048; p=0.038), and working in underground mining for 25 years or more (for those with 25.0-29.9 years: PR=2.199, 95% CI: 1.449 - 3.338; p=0.001). Conclusions: The prevalence of pneumoconiosis was very high and was found to be associated with severe exposure to coal dust, work exposure for 25 years or more and working in medium-sized enterprises.

Evaluation of the exposure to coal dust and prevalence of pneumoconiosis in underground mining in three Colombian departments / Evaluación de la exposición al polvo de carbón y de sílice en sitios de minería subterránea en tres departamentos de Colombia

Introduction: Coal workers' pneumoconiosis is a chronic and irreversible disease representing a public health problem. Objective: To estimate the prevalence of pneumoconiosis and its associated factors among underground coal miners in the Colombian departments of Boyacá, Cundinamarca and Norte de Santander. Materials and methods: We conducted a cross-sectional study of 476 miners to measure the prevalence of pneumoconiosis and its associated factors such as coal dust and silica levels, as well as the occupational conditions. The medical assessment and a chest x-ray were performed according to the International Labor Organization criteria, along with spirometry and the identification of glutathione S-transferase and repair enzyme polymorphisms.The associations were explored using Cox regression models. Results: We performed a total of 479 environmental monitoring sessions in 31 companies and we evaluated 476 workers with 10 to 57 years of mining work experience. The prevalence of pneumoconiosis was 33.8% (95% CI: 27.0 - 41.3%). In the Cox multivariate regression model with a constant risk time, pneumoconiosis was significantly associated with working in medium-sized companies (PR=2.00, 95% CI: 0.995 - 2.690; p=0.052), the level of severe exposure to coal dust (PR=2.055, 95% CI: 1.043 - 4.048; p=0.038), and working in underground mining for 25 years or more (for those with 25.0-29.9 years: PR=2.199, 95% CI: 1.449 - 3.338; p=0.001). Conclusions: The prevalence of pneumoconiosis was very high and was found to be associated with severe exposure to coal dust, work exposure for 25 years or more and working in medium-sized enterprises

Introducción. La neumoconiosis de mineros del carbón es una enfermedad crónica e irreversible que se considera un problema de salud pública. Objetivo. Estimar la prevalencia de neumoconiosis y sus factores asociados en mineros de carbón de Boyacá, Cundinamarca y Norte de Santander. Materiales y métodos. Se hizo un estudio de corte transversal en 476 mineros. Se les hizo valoración médica, se tomaron radiografías de tórax siguiendo los criterios de la Organización Internacional del Trabajo, así como espirometrías, y se identificaron los polimorfismos de la glutatión S-transferasa y de las enzimas de reparación. Las asociaciones entre las condiciones ocupacionales y de la empresa con la neumoconiosis, se estudiaron usando modelos de regresión de Cox. Resultados. En 31 empresas se hicieron 479 monitorizaciones ambientales y se evaluaron 476 trabajadores cuyo tiempo de trabajo fluctuaba entre 10 y 57 años. La prevalencia de la neumoconiosis fue de 33,8 % (IC95% 27,0-41,3). En el modelo de regresión multivariado de Cox, con tiempo de riesgo constante para la neumoconiosis, esta se asoció significativamente con el trabajo en empresas medianas (razón de prevalencias, RP=2,00; IC95% 0,995- 2,690; p=0,052), con un nivel alto de exposición al polvo de carbón según el índice de exposición (RP=2,055; IC95% 1,043-4,048; p=0,038), y una antigüedad de 25 años o más (para 25,0 a 29,9 años: RP=2,199; IC95% 1,449-3,338; p=0,001). Conclusiones. La prevalencia de la neumoconiosis fue muy alta y se asoció a la exposición a altos niveles de polvo de carbón, a una exposición laboral mayor o igual a 25 años y al trabajo en empresas medianas.

Un análisis comparativo cualitativo de signos y síntomas de intoxicación con mezclas a base de heptacloro / A qualitative comparative analysis of signs and symptoms of heptachlor-based mixtures poisoning

Las mezclas químicas o la presencia conjunta de signos y síntomas de intoxicación crónica son dos de los principales desafíos para el estudio toxicológico y epidemiológico de la exposición a plaguicidas. En este estudio fue explorada la aplicabilidad del análisis cualitativo comparativo con conjuntos nítidos (csQCA) para superar estas difcultades. Los datos de síntomas y signos clínicos de intoxicación de 43 trabajadores del cultivo de arroz en Guamo y Espinal (Tolima, Colombia) fueron recolectados, y se midió la presencia de heptacloro en sangre total con cromatografía de gases con detector de captura de electrones. Se realizaron tablas de verdad con las principales confguraciones (presencia conjunta de signos y síntomas), y se evaluó su consistencia y cobertura. En 90,70 % de los trabajadores se detectó heptacloro. Cuarenta y nueve signos y síntomas fueron reportados, siendo los más frecuentes las alteraciones del sueño, el mareo y la visión borrosa. Cinco confguraciones resultaron asociadas con la detección de heptacloro en sangre (cobertura: 0,872 y consistencia: 0,971), aunque sólo tres resultan útiles para la práctica clínica. Este procedimiento permitió diseñar un listado de tamizaje para detección de individuos con exposición a heptacloro. La experiencia mostró uno de los potenciales uso de csQCA en toxicología. Futuros estudios podrán explorar mejor el valor predictivo de estos hallazgos en diversas poblaciones.

Chemical mixtures or the conjoint presence of signs and symptoms of chronic poisoning are two of the main challenges to the toxicologic and epidemiologic study of exposure to pesticides. In this study was explored the applicability of crispsets qualitative comparative analysis (csQCA) to overcome these diffculties. Data on symptoms and signs of poisoning from 43 agricultural workers living in Guamo or Espinal (Cundinamarca, Colombia) were collected, and the presence of heptachlor was measured in total blood with gas chromatography with electron capture detector. Truth tables with main confgurations were performed, and consistence and coverage were estimated. Heptachlor was detected among 90.70% of workers. Forty-nine symptoms and signs were reported, being the most frequent sleep disorders, dizziness and blurred vision. Five confgurations were associated with the detection of heptachlor in blood (coverage: 0.872 and consistence: 0.971), although only three are useful for clinical practice. This procedure allowed the design of a list of screening for detection of individuals with exposure to heptachlor. This experience showed one of the potential uses of csQCA in toxicology. Future studies may further explore the predictive value of these fndings in different populations.

[Evaluation of exposure of auto painters to organic solvents in the city of Bogota]. / Evaluación de la exposición a solventes orgánicos en pintores de carros de la ciudad de Bogotá.

INTRODUCTION: Painters of automobiles are exposed to pure and mixed solvents that have been associated with neurological effects and carcinogenic mutations. OBJECTIVE: To characterize the health and work conditions of individuals who are occupationally exposed to organic solvents used in sheet metal and auto body shops in Bogota. MATERIALS AND METHODS: Descriptive, cross-sectional study that characterizes the health and work conditions of individuals exposed to organic solvents in sheet metal and auto body shops in Bogota. A group exposed to the solvents was compared to an unexposed group. Air concentrations of benzene, toluene and xylene (BTX) were determined, individual questionnaires were administered and phenylmercapturic, hippuric and ortho- and para-methylhippuric acids were measured in urine. The results of the measurements and the questionnaires were correlated to determine the exposure panorama. RESULTS: For the three BTX metabolites, statistically significant differences (p<0.001) were found between the population exposed to the solvents and the unexposed population. For the exposed population, positive correlations were found between toluene in air and hippuric acid in urine (rho=0.82) and between xylene in air and o-methylhippuric acid in urine (rho=0.76). Hippuric acid values exceeded permissible levels in 11 workers and p-methylhippuric acid exceeded permissible levels in 8 workers. None of the phenylmercapturic values exceeded the limit. CONCLUSION: Auto painters are exposed to high levels of organic solvents at the workplace and do not have adequate industrial health and safety conditions to perform their jobs.

Evaluación de la exposición a solventes orgánicos en pintores de carros de la ciudad de Bogotá / Evaluation of exposure of auto painters to organic solvents in the city of Bogota

Introducción. Los pintores de vehículos automotores están expuestos a solventes puros o mezclas, los cuales se han asociado con efectos neurológicos, mutagénicos y cancerígenos. Objetivo. Caracterizar las condiciones de salud y de trabajo de individuos expuestos a solventes orgánicos empleados en talleres de lámina y pintura de carros de Bogotá. Materiales y métodos. Se hizo un estudio transversal descriptivo en el que se caracterizaron las condiciones de salud y de trabajo de individuos expuestos a solventes orgánicos en talleres de lámina y pintura en Bogotá. Se comparó un grupo de trabajadores expuestos a solventes orgánicos con un grupo no expuesto. Se determinaron las concentraciones de benceno, tolueno y xileno en el aire, se hizo una encuesta individual y se midieron los ácidos fenil-mercaptúrico, hipúrico, orto y para-metilhipúrico en orina. Los resultados de las mediciones y de la encuesta se correlacionaron para establecer el panorama de exposición. Resultados. Hubo diferencias estadísticamente significativas entre la población expuesta y la no expuesta a solventes (p<0,001) en cuanto a los tres metabolitos de benceno, tolueno y xileno. Se encontraron correlaciones positivas entre el tolueno en el aire y el ácido hipúrico en la orina de los individuos expuestos (ro=0,82), y entre el xileno en el aire y el ácido o-metilhipúrico (ro=0,76). Los valores del ácido hipúrico estuvieron por encima de los límites permisibles en 11 trabajadores y, los de ácido p-metilhipúrico, en ocho de ellos. No se registraron valores de ácido fenil-mercaptúrico por fuera del límite permitido. Conclusión. Los pintores de carros están expuestos a niveles altos de solventes orgánicos en sus sitios de trabajo, y no tienen condiciones adecuadas de higiene y seguridad industrial para realizar sus labores.

Introduction: Painters of automobiles are exposed to pure and mixed solvents that have been associated with neurological effects and carcinogenic mutations. Objective: To characterize the health and work conditions of individuals who are occupationally exposed to organic solvents used in sheet metal and auto body shops in Bogota. Materials and methods: Descriptive, cross-sectional study that characterizes the health and work conditions of individuals exposed to organic solvents in sheet metal and auto body shops in Bogota. A group exposed to the solvents was compared to an unexposed group. Air concentrations of benzene, toluene and xylene (BTX) were determined, individual questionnaires were administered and phenylmercapturic, hippuric and ortho- and para-methylhippuric acids were measured in urine. The results of the measurements and the questionnaires were correlated to determine the exposure panorama. Results: For the three BTX metabolites, statistically significant differences (p<0.001) were found between the population exposed to the solvents and the unexposed population. For the exposed population, positive correlations were found between toluene in air and hippuric acid in urine (rho=0.82) and between xylene in air and o-methylhippuric acid in urine (rho=0.76). Hippuric acid values exceeded permissible levels in 11 workers and p-methylhippuric acid exceeded permissible levels in 8 workers. None of the phenylmercapturic values exceeded the limit. Conclusion: Auto painters are exposed to high levels of organic solvents at the workplace and do not have adequate industrial health and safety conditions to perform their jobs.

Validación del método analítico para la determinación de mercurio total en sangre humana por Espectrofotometría de absorción atómica Zeeman RA-915+ con el módulo de pirolisis Pyro-915+ / ANALYTICAL METHOD VALIDATION FOR DETERMINATION OF TOTAL MERCURY IN HUMAN BLOOD BY Zeeman MERCURY SPECTROMETER RA-915+ WITH THE PYROLYSIS MODULE PYRO-915+ / Validação de mtoodo analítico para a determinação do teor de mrcúrio em humannos por espectrometria de absorção atômica ra-915 + zeeman pyrolysis módulo com piro-915 +

Este artículo describe la metodología de validación para la técnica de identificación de mercurio total en muestras de sangre por espectrofotometría de absorción atómica Zeeman RA-915+ con el módulo de Pirólisis PYRO-915+, adecuada para la determinación directa de las concentraciones de mercurio total en varias matrices, que a diferencia de otras técnicas de atomización (horno de grafito, vapor frio, o generador de hidruros) no necesita un pre-tratamiento de la muestra. Con la aplicación de ésta validación en la realización de los análisis se brinda la confiabilidad necesaria en la obtención y emisión de los resultados. La mayoría de parámetros de la validación, se sometieron a análisis de varianza tipo ANOVA con un nivel de confianza del 95 %. Se obtuvo un límite de detección de 2.16 üg/L, un límite de cuantificación de 5.54 üg/L y una linealidad en el rango de 5.54 üg/L a 100 üg/L, adicionalmente, se evaluó exactitud y precisión, obteniendo resultados favorables para el análisis. El cálculo de la incertidumbre expandida para este método fue 0.610 üg/L.

This article describes the methodology of the validation about the identification of total mercury in blood samples by Zeeman atomic absorption spectrophotometry RA-915+ with the module of Pyrolysis PYRO-915+, suitable for the direct determination of total mercury concentrations in various matrices, that unlike other atomization techniques (graphite furnace, cold vapor or hydride generator) does not require a sample pre-treatment. With the application of this validation,is provided the reliability in the results. Most of the validation parameters were subjected to analysis of variance ANOVA with a confidence level of 95%. It was obtained a detection limit of 2.16 üg/L, a quantitation limit of 5.54üg/L and linearity in the range of 5.54 üg/L to , in addition, the precision and accuracy was evaluated, obtaining favorable results in the analysis. The calculation of the expanded uncertainty for this method was 0.610 üg/L.

Este artigo descreve a metodologia de validação da técnica de identificação de mercúrio total em amostras de sangue por espectrofotometria de absorção atômica RA-915+ Zeeman com módulo de Pirólise piro-915+, adequado para a determinação direta das concentrações de mercúrio total em várias matrizes, em comparação com outras técnicas de atomização (forno de grafite, vapor frio oude geradores de hidretos) não requer um pré-tratamento da amostra. Com a aplicação desta validação na realização dos análises se atinge a confiabilidade exigida na obtenção e emissão dos resultados. A maioria dos parâmetros de validação foram submetidos a análise de variância tipo ANOVA com um nível de confiança de 95%. Foi obtido um limite de detecção de 2.16 üg/L, um limite de quantificação de 5.54üg/Le uma linearidade no intervalo de 5.54 a 100 üg/L, além disso, a precisão e a exactidão foi avaliada, obtendo-se resultados favoráveis ​​para o análise. O cálculo da incerteza expandida para este método foi 0.610 üg/L.