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7 resultados encontrados para: AUTOR: Pérez Maldonado, Iván Nelinho
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Índice | Resumen en: Español |
Resumen en español

En el presente trabajo se realizó un monitoreo en familias de jornaleros expuestos a Compuestos Orgánicos Persistentes (COPs) en las comunidades de Cárdenas, Huixtla y Chetumal, utilizando biomarcadores de exposición a COPs en sangre mediante cromatografía de gases acoplado a un espectrómetro de masas (GC/MS), así como la aplicación del biomarcador de genotoxicidad conocido como “ensayo cometa” , para la evaluación del daño al ácido desoxirribonucleico (ADN) en células mononucleares de sangre periférica (PBMC). Los resultados indicaron que la comunidad de Chetumal presentó los mayores niveles de mezcla de COPs al igual que los mayores niveles de daño al ADN en los jornaleros de la caña de azúcar con una diferencia estadística significativa (P < 0.05), comparado con las comunidades Control, Cárdenas y Huixtla. Asimismo, se encontró que el (1,1-Dicloro-2,2-bis (4- clorofenil) etileno) DDE principal metabolito del DDT (1, 1,1-tricloro-2,2-bis (4-clorofenil) etano) fue el compuesto con mayor influencia sobre la fragmentación de la molecular del ADN presentando una correlación estadística significativa (P = 0.001, r2 = 0.6146).

Índice

Capítulo 1. Introducción
Capítulo 2. Revisión bibliográfica
2.1 Los contaminantes orgánicos persistentes
2.1.1 Clasificación
2.1.2 Efectos en organismos
2.1.3 Mecanismos de acción tóxica de los COPs sobre el ADN
2.1.4 Plan Nacional de Implementación del Convenio de Estocolmo en México
2.1.5 Los COPs en México
2.1.6 Biomarcadores
Capitulo 3. Justificación
3.1 Problema de investigación
Capitulo 4 Objetivos
4.1 Objetivo General
4.2 Objetivos específicos
Capítulo 5. Metodología
5.1 Selección de los sitios
5.2 Procedimiento para la obtención de información
5.3 Recolección de muestras
5.4 Procedimiento para el análisis de los datos
5.4.1 Ensayo cometa
5.4.2 Cuantificación de metabolitos
5.5 Análisis estadístico
5.6 Aspectos éticos de la investigación
Capítulo 6. Resultados
6.1 Evaluación de daño al ADN por comunidad
6.2 Evaluación de la exposición a COPs
6.2.1 COPs no detectados en sangre
6.2.2 COPs encontrados en sangre
6.2.3 α-HCH; β-HCH; y, γ-HCH
6.2.4 ΣDDTs
6.2.5 PCBs
6.3 Factores sociodemográficos y su relación con los niveles de COPs y daño al ADN
6.3.1 El lugar de residencia y su relación con los niveles de COPs y daño al ADN
6.3.2 El sexo y su relación con los niveles de COPs y Daño al ADN
3.3.3 La edad y su relación con los niveles de COPs y el Daño al ADN
3.3.4 La ocupación y su relación con los niveles de COPs y el Daño al ADN
3.3.5 La aplicación de plaguicidas y su relación con los niveles de COPs y el Daño al ADN
3.3.6 El consumo de tabaco y su relación con los niveles de COPs y el Daño al ADN
3.3.7 El consumo de alcohol y su relación con los niveles de COPs y el Daño al ADN
6.4 Relación del Daño al ADN con los niveles de la mezcla de COPs
6.4.1 Relación del Daño al ADN con los niveles de ΣHCHs-ΣPCBs y ΣDDTs

6.4.2 Relación del Daño al ADN con los niveles de ΣDDTs, DDT y DDE
Capítulo 7. Discusión
7.1 Daño al ADN por comunidad
7.2 Niveles de ΣCOPs
7.2.1 Niveles de ΣHCHs
7.2.2 Niveles de ΣDDTs
7.2.3 Niveles de PCBs en sangre
7.3 Factores sociodemográficos y su relación con el daño al ADN y los niveles de COPs
7.4 Relación del daño al ADN y los niveles de ΣCOPs (HCHs, DDTs, y PCBs)
7.4.1 Relación del Daño al ADN con los niveles de ΣHCHs-ΣPCBs y ΣDDTs
7.4.2 Relación del Daño al ADN con los niveles de ΣDDTs, DDT y DDE
Capítulo 8. Conclusiones
Capítulo 9. Perspectivas de investigación
Capítulo 10. Literatura Citada
Capítulo 11. Anexos


Resumen en: Inglés |
Resumen en inglés

It has been demonstrated that the human biomonitoring of susceptible populations is a valuable method for the identification of critical contaminants. Therefore, the purpose of this study was to assess the exposure profile for arsenic (As), lead (Pb), mercury (Hg), 1-hydroxypyrene (1-OHP), 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in children living in Ciudad Juarez, Chihuahua, Mexico (a major manufacturing center in Mexico). In 2012, we evaluated a total of 135 healthy children living in Ciudad Juarez since birth. The total PBDEs levels ranged from nondetectable (< LOD) to 215 ng/g lipid, with a mean total PBDEs level of 29.5 ± 53.0 ng/g lipid (geometric mean ± standard deviation). The mean total PCBs level in the study participants was 29.0 ± 10.5 ng/g lipid (range 4.50–50.0 ng/g lipid). The mean concentration of total DDT (DDT + DDE) was 11.9 ± 6.70 ng/g lipid (range 3.00–26.0 ng/g lipid). The mean 1-OHP levels was 1.2 ± 1.1 µmol/mol creatinine (range <LOD to 3.90 µmol/mol creatinine). Regarding heavy metals levels, the mean urinary As levels was 19.5 ± 3.07 µg/g creatinine, for urinary mercury the levels ranged from <LOD to 11.5 µg/L, with a mean value of 2.10 µg/L, and finally, the mean blood lead level was 4.20 ± 3.80 µg/dL. In conclusion, our data indicate high exposure levels to chemicals analyzed in the children living in the study community. Therefore, a biomonitoring program for the surveillance of the child population in Ciudad Juarez is necessary.


Resumen en: Inglés |
Resumen en inglés

The purpose of this study was to assess the levels of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDE), and four heavy metals (arsenic, cadmium, and lead) in outdoor surface soils (50 samples) collected from the metropolitan area of Monterrey in Mexico. Total PBDEs levels ranged from 1.80 to 127 µg/kg, with mean total PBDEs level of 14.2 ± 21.5 µg/kg (geometric mean ± standard deviation). For PCBs, the mean total level in the studied soils was 23.5 ± 20.2 µg/kg (range 4.0–65.5 µg/kg). An important finding in our study was that all soil samples (100 %) had detectable levels of the metabolite p,p′-DDE. Moreover, the mean total DDT level (∑p′p-DDT and p′p-DDE) was approximately 132 ± 175 µg/kg. The mean levels for arsenic, cadmium, and lead in soil were 5.30 ± 1.35 (range 1.55–7.85) mg/kg, 2.20 ± 1.20 (range 0.65–6.40) mg/kg, and 455 ± 204 (range 224–1230) mg/kg, respectively. Our study has several limitations, the most notable of which is the small sample of soils evaluated. However, this screening study provided concentration data for the occurrence of POPs and four heavy metals in soil from the metropolitan area of Monterrey, Nuevo Leon, Mexico, and taking into consideration that soil is an important pathway of exposure for people, a biomonitoring program for the surveillance of the general population in the metropolitan area of Monterrey, Nuevo Leon is deemed necessary.


Resumen en: Inglés |
Resumen en inglés

The Coatzacoalcos Region in Veracruz, Mexico houses one of the most important industrial complexes in Mexico and Latin America. Lead is an ubiquitous environmental pollutant which represents a great risk to human health and ecosystems. Amphibian populations have been recognized as biomonitors of changes in environmental conditions. The purpose of this research is to measure exposure to lead and evaluate hematological and biochemical effects in specimens of giant toads (Rhinella marina) taken from three areas surrounding an industrial complex in the Coatzacoalcos River downstream. Lead levels in toads' blood are between 10.8 and 70.6 μg/dL and are significantly higher in industrial sites. We have found a significant decrease in the delta-aminolevulinic acid dehydratase (δ-ALAD) activity in blood from 35.3 to 78 % for the urban-industrial and industrial sites, respectively. In addition, we have identified a strong inverse relationship between the δ-ALAD activity and the blood lead levels (r = -0.84, p < 0.001). Hemoglobin and mean corpuscular hemoglobin levels, as well as the condition factor, are found to be lower at industrial sites compared with the reference sites. Our results suggest that the R. marina can be considered a good biomonitor of the δ-ALAD activity inhibition and hematological alterations at low lead concentrations.


5.
- Artículo con arbitraje
Resumen en: Inglés |
Resumen en inglés

In Mexico, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) was used until the year 2000, principally in agriculture and anti-paludal program health campaigns. The southeastern region of Mexico was an important area of malaria, and from 1957 DDT was applied indoors every 6 months, with a coverage of 2 g/m2. The current study was performed in Tabasco, a Mexican state located in the southeastern region of Mexico. DDT and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene (DDE) were analyzed by gas chromatography/mass spectrometry. In general, low levels were found in household outdoor samples; the levels of DDT ranged from not detectable to 0.048 mg/kg, and of DDE from 0.001 to 0.068 mg/kg. An important finding was that, in all communities where DDT in blood was analyzed, exposure to DDT was found, indicating both past and present exposure. Although the levels found in this study were lower than other studies in Mexico, there is a need to evaluate whether the people living in the study area are at risk.


Resumen en: Inglés |
Resumen en inglés

The Coatzacoalcos Region in Veracruz, Mexico houses one of the most important industrial complexes in Mexico and Latin America. Lead is an ubiquitous environmental pollutant which represents a great risk to human health and ecosystems. Amphibian populations have been recognized as biomonitors of changes in environmental conditions. The purpose of this research is to measure exposure to lead and evaluate hematological and biochemical effects in specimens of giant toads (Rhinella marina) taken from three areas surrounding an industrial complex in the Coatzacoalcos River downstream. Lead levels in toads' blood are between 10.8 and 70.6 μg/dL and are significantly higher in industrial sites. We have found a significant decrease in the delta-aminolevulinic acid dehydratase (δ-ALAD) activity in blood from 35.3 to 78 % for the urban–industrial and industrial sites, respectively. In addition, we have identified a strong inverse relationship between the δ-ALAD activity and the blood lead levels (r = −0.84, p < 0.001). Hemoglobin and mean corpuscular hemoglobin levels, as well as the condition factor, are found to be lower at industrial sites compared with the reference sites. Our results suggest that the R. marina can be considered a good biomonitor of the δ-ALAD activity inhibition and hematological alterations at low lead concentrations.


7.
Artículo
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Resumen en: Español | Inglés | Portugués |
Resumen en español

Los métodos para evaluar el riesgo en salud se basan, en general, en el monitoreo ambiental y en la estimación de la exposición a través de modelos matemáticos. La incertidumbre de tal estrategia es grande. En consecuencia, para incrementar la certidumbre sobre la evaluación de la exposición a los contaminantes, se ha propuesto el empleo de biomarcadores. No obstante, la complejidad de los nuevos escenarios de riesgo obliga a evaluar no solamente a las poblaciones humanas sino también al resto de la biota. Asimismo, factores ambientales, sociales y de salud, al afectar la vulnerabilidad, también deben ser considerados para la caracterización del riesgo. Estos factores de vulnerabilidad pueden evaluarse a través de indicadores. Al final, con los análisis ambientales, el uso de biomarcadores y el manejo de indicadores ambientales, sociales y de salud, puede evaluarse el riesgo de manera integrada (humanos y biota). En esta revisión se presentan las diversas estrategias empleadas por este grupo de trabajo para evaluar el riesgo en sitios contaminados, comunidades marginadas y en áreas afectadas por el cambio global climático.

Resumen en inglés

The most commonly used methods for risk assessment are based on environmental analysis and the use of mathematical models for the estimation of exposure. However, the uncertainty of this approach is high, as the models are based on scenarios that may be not the correct ones. In order to decrease the uncertainty, the use of biomarkers has been proposed. Furthermore, considering the complexity of pollution in some sites, these biomarkers can be used both in humans and biota in order to obtain better information for the definition of risks at those sites. In addition to biomarkers, social, health and environmental indicators have to be applied for risk characterization, as different factors of vulnerability can modify the extent of health risks in some communities. At the end, with environmental monitoring and the use of biomarkers and indicators of vulnerability, health risks in humans and biota (integrated risk assessment) can be assessed in different scenarios. In this paper we present the strategies that our group developed for the study of hazardous waste sites, vulnerable communities and areas impacted by climate change.

Resumen en portugués

Os métodos para avaliar o risco na saúde se baseiam, em geral, no monitoramento ambiental e na estimação da exposição através de modelos matemáticos. A incerteza de tal estratégia é grande. Em consequência, para incrementar a certeza sobre a avaliação da exposição aos contaminantes, tem sido proposta a utilização de biomarcadores. No entanto, a complexidade dos novos cenários de risco obriga a avaliar não somente as populações humanas mas também ao resto da biota. Da mesma forma, fatôres ambientais, sociais e de saúde, ao afetar a vulnerabilidade, também devem ser considerados para a caracterização do risco. Estes fatôres de vulnerabilidade podem avaliar-se através de indicadores. Finalmente, com as análises ambientais, o uso de biomarcadores e o manejo de indicadores ambientais, sociais e de saúde, pode-se avaliar o risco de maneira integrada (humanos e biota). Nesta revisão se apresentam as diversas estratégias empregadas por este grupo de trabalho para avaliar o risco em lugares contaminados, comunidades marginalizadas e em áreas afetadas pela mudança global climática.