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Papers by octavio carvajal

Revista Internacional De Contaminacion Ambiental, Sep 1, 2005

Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs a... more Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs and livestock to combat ectoparasites. Due to their chemical stability, persis tence and lipophility, their residues bioconcentrate in lipidrich tissues, according to the equilibrium pattern of internal transport and lipid tissue content. The studies on their role as estrogenic or antiandrogenic agents have related these pesticides to breast cancer. Therefore, organochlorine pesticides were determined in breast adipose tissue of women subjected to surgery due to the diagnosis of breast abnormalities. The study pool consti tuted 127 women with malignant breast tumors, 127 with benign breast tumors and 127 in a control group without breast abnormalities. The pesticides determined were: HCB, b HCH, pp'DDE, op'DDT, pp'DDT and SDDT. Comparing the studied groups, the highest residue levels were determined in the benign breast tumor group. The determined levels from the control group through malignant to benign cases increased stepwise; HCB: 0.045, 0.099, 0.116 mg kg 1 , bHCH: 0.163, 0.265, 0.319 mg kg 1 , pp'DDE: 0.782, 0.980, 1.761 mg kg 1 , op'DDT: 0.035, 0.094, 0.176 mg kg 1 , pp'DDT: 0.296, 0.351, 0.661 mg kg 1 , SDDT: 1.112, 1.423, 2.601 mg kg 1 , respectively. Paired analyses of the three groups revealed divergences among them and correlation of these pesticide levels with breast tumors. Calculated relative risk (RR) values for the benign to control group and the malignant to control cases presented the following values:

La isotretinoina es un retinoide sintetico utilizado en el tratamiento de diversas enfermedades d... more La isotretinoina es un retinoide sintetico utilizado en el tratamiento de diversas enfermedades dermatologicas, de las cuales la mas frecuente es el acne inflamatorio severo. Desde el inicio de su utilizacion se ha reportado un aumento de los casos de depresion e ideacion suicida en pacientes tratados con este medicamento, aunque no se ha determinado si se trata de una relacion directa con el medicamento o con la enfermedad de fondo en una poblacion especialmente susceptible. En esta revision se analiza la informacion mas reciente acerca de la posibilidad de una relacion directa entre el consumo de isotretinoina y el riesgo de intento de suicidio o suicidio consumado.

Revista Internacional De Contaminacion Ambiental, 2004

Revista Internacional De Contaminacion Ambiental Vol 20 No 4 185 192, Sep 13, 2011

Many papers describe the analytical methods for organochlorine pesticide residue determination in... more Many papers describe the analytical methods for organochlorine pesticide residue determination in environmental samples. Gas chromatography with electron capture detection requires an efficient clean-up step of extracts. To reach this purpose, the adsorbents such as florisil, aluminium oxide and silica gel are employed. Most of organochlorine pesticides are resistant to sulfuric acid, characteristic that was used in the destruction of organic compounds of sample origin. The analytical methods that use sulfuric acid as a clean-up medium during the determination of organochlorine pesticide residues in the following samples are described: soil and sediments, vegetables and tubercles, grains, straw, tobacco, fatty samples of animal origin such as adipose tissue and milk fat, blood serum and semen. The analytical quality study done for each sample type, expressed as mean with standard deviation and percent of variation, gave values higher than 90 % of recovery and a variation smaller than 10 %. According to the criteria of the Association of Official Analytical Chemists of USA, the obtained values considered the described methods as excellent in recovery and with acceptable variability. Moreover, the use of sulfuric acid makes the method cheap, eliminating the adsorbents and diminishing the volume of solvents.

Salud Pública de México, 1997

Carvajal O, Angulo O. Efecto de los ácidos grasos polinsaturados n-3 en el perfil lipídico de mex... more Carvajal O, Angulo O. Efecto de los ácidos grasos polinsaturados n-3 en el perfil lipídico de mexicanos voluntarios.

Nutrition Research, 2002

We examined clearance rates in serum of lymph lipids collected from rats fed a diet containing on... more We examined clearance rates in serum of lymph lipids collected from rats fed a diet containing one of four types of structured triglycerides containing linoleic and medium-chain fatty acids, 1) sn-1 (3) medium-chain fatty acids-sn-2 linoleic acid (MLM), 2) interesterified MLM (iMLM), 3) sn-2 mediumchain fatty acids-sn-1 (3) linoleic acid (LML), and 4) interesterified LML (iLML). Rats with permanent cannulation of thoracic duct were fed a diet containing one of the structured triglycerides and then, thoracic duct lymph was collected. The lymph was injected into the right superior vena cava in rats fed the same diet for a week. Half-life of triglyceride was significantly longer in rats injected the lymph originated from rats fed LML compared to the other groups. Half-life of retinyl palmitate, a marker of chylomicron remnant, tended to be longer in the LML group. These observations suggest that the structural differences in triglycerides containing medium-chain fatty acids and linoleic acid can alter the rate of lipid clearance in serum of rats.

Journal of the Science of Food and Agriculture, 2003

Honey is obtained from the hives of European honeybees. Honeybees can be infested by Varroa paras... more Honey is obtained from the hives of European honeybees. Honeybees can be infested by Varroa parasitism, which affects honey production. The acaricide τ-fluvalinate used in beehives to control Varroa mites, can leave its residues in honey, pollen and wax. A monitoring study was undertaken to determine the τ-fluvalinate residues in honey samples taken from treated hives. The τ-fluvalinate residues were determined by gas chromatography using a short, non-polar packed column with electron capture detection. Analysis of 50 samples showed an average residue level of 15 µg kg−1. The same samples were filtered through Whatman filter paper to separate the honey from residual suspended particles. The filtered honeys showed no acaricide residues above the detection limit of 3 µg kg −1, while the average residue level determined in the sediments was 392 µg kg −1. Thus the residues of τ-fluvalinate in honey can be eliminated by separating the honey from residual suspended particles that contain acaricide residues. Copyright © 2003 Society of Chemical Industry

Journal of Agricultural and Food Chemistry, 2004

The organochlorine pesticides are lipophilic and persistent and tend to accumulate in soils and g... more The organochlorine pesticides are lipophilic and persistent and tend to accumulate in soils and growing plants. The contamination of growing plants occurs by adhesion of volatile substances from the air to the plant surface and by the migration of contaminants through xylem in inner ascendant transport. Persistent organochlorine pesticides (HCB, alpha,gamma-HCH, pp'DDE, op'DDT, pp'DDT) levels were determined in soils and rye plants. The aims of the study were the monitoring of organochlorine pesticide concentrations and the comparison of these levels among soil, rye straw, and rye grains. Fifty soil samples and 50 rye plant (50 straw and 50 grains) samples were taken. The GLC-ECD chromatographic results indicated the following contamination levels distributed among soil, straw, and grains: HCB (0.7-1.2-0.7 microg.kg(-1)), alpha-HCH (0.6-3.4-1.2 microg.kg(-1)), gamma-HCH (1.8-27.3-4.4 microg.kg(-1)), Sigma-HCH (2.5-30.7-5.6 microg.kg(-1)), pp'DDE (1.0-7.8-5.5 microg.kg(-1)), op'DDT (16.1-20.4-17.0 microg.kg(-1)), pp'DDT (38.0-41.7-49.6 microg.kg(-1)), and Sigma-DDT (54.2-63.2-72.1 microg.kg(-1)). The study verified the presence of organochlorine pesticides in the Mexican agricultural environment and their migration from soil to the growing rye plants. However, DDT has been banned since 1999 for sanitary reasons, and Lindane is applied only in some cases as a seed dresser. The determined organochlorine pesticide levels in rye plants are low, at residual levels that are below Codex Alimentarius Commission maximum residue limits.

Bulletin of Environmental Contamination and Toxicology, 2005

Bulletin of Environmental Contamination and Toxicology, 2002

Bulletin of Environmental Contamination and Toxicology, 2004

Bulletin of Environmental Contamination and Toxicology, 2008

Agricultural cultivation assists organochlorine pesticide migration from contaminated soils to gr... more Agricultural cultivation assists organochlorine pesticide migration from contaminated soils to growing plants. This phenomenon is caused by retention processes that modify volatile pesticide exchange between soil, air and plants. The aim of the study was to monitor organochlorine pesticide (HCB, aand c-HCH, pp 0 DDE, op 0 DDT, pp 0 DDT) levels and compare these concentrations in soil, carrot roots and carrot leaves. Fifty soil samples, 50 carrot root and 50 carrot leaf samples were taken from the same fields and analyzed by GLC-ECD. The results reveal organochlorine pesticide diffusion from agricultural soils to growing carrot plants and their vapors adsorbtion by leaves. Within the carrot plant, organochlorine pesticides accumulate especially in carrot root peel, 3-7 times more than in root flesh.

Bulletin of Environmental Contamination and Toxicology, 2009

Breast milk is considered the most important route in the elimination of deposited organochlorine... more Breast milk is considered the most important route in the elimination of deposited organochlorine pesticides in a mother's body. The equilibrium of organochlorine pesticides in the human body considers the elements of internal transport processes, the equilibrium pattern between pesticides and tissue fat contents, and the mobilization of lipids and lipoproteins among body parts. The aim of this study was to determine organochlorine pesticide levels in breast milk samples from the 4th to the 30th day of lactation and the trend in their concentration time so as to forecast the time tendency of residue levels and the pesticide excretion pattern. Milk samples were taken from forty participants and analyzed by GLC-ECD. The organochlorine pesticide residues determined in the breast milk samples during lactation decreased: b-HCH from 0.095 to 0.066 mg/kg, pp 0 DDE from 1.807 to 1.423 mg/kg and pp 0 DDT from 0.528 to 0.405 mg/kg, at the characteristic rate for each compound. The obtained results compared with the calculated fits of forecasts were parallel and did not exhibit significant differences. The newborn baby exposed during lactation had organochlorine pesticide residues whose levels decreased permanently. The levels depended not only on the breast milk nutrition, but also on the total environmental exposures which included air pollution as a significant contamination source.

Bioscience, Biotechnology, and Biochemistry, 2000

Revista Internacional …, 2010

Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs a... more Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs and livestock to combat ectoparasites. Due to their chemical stability, persis tence and lipophility, their residues bioconcentrate in lipidrich tissues, according to the equilibrium ...

Archives of Environmental Health: An International Journal, 2004

Samples of human blood sera (N = 118) for the determination of organochlorine pesticide levels we... more Samples of human blood sera (N = 118) for the determination of organochlorine pesticide levels were obtained at autopsy from auto accident victims in Veracruz, Mexico, during the years 2000 and 2001. The presence of hexachlorobenzene (HCH), beta-hexachlorocyclohexane (beta-HCH), 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDT), and o,p'-DDT was confirmed by gas-liquid-electron-capture detection chromatography. During the years 2000 and 2001, the respective mean levels of (a) HCB, (b) beta-HCH, (c) p,p'-DDE, (d) o,p'-DDT, (e) p,p'-DDT, and (f) total DDT were (a) 2.1 ng/ml and 1.4 ng/ml, (b) 3.0 ng/ml and 3.6 ng/ml, (c) 21.1 ng/ml and 23.8 ng/ml, (d) 1.2 ng/ml and 0.8 ng/ml, (e) 3.3 ng/ml and 2.5 ng/ml, and, finally, (f) 25.4 ng/ml and 27.1 ng/ml, respectively. High levels of persistent organochlorine pesticides were--and continue to be--present in the blood of individuals who live in Mexico. Levels of insecticide metabolites (e.g., beta-HCH, p,p'-DDE) in blood have increased during recent years (1997-2001), but levels of p,p'-DDT decreased in 2001 because the use of DDT for the control of malaria in Mexico was restricted.

How to cite Complete issue More information about this article Journal's homepage in redalyc.org ... more How to cite Complete issue More information about this article Journal's homepage in redalyc.org Scientific Information System Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Non-profit academic project, developed under the open access initiative

Revista Internacional De Contaminacion Ambiental, Sep 1, 2005

Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs a... more Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs and livestock to combat ectoparasites. Due to their chemical stability, persis tence and lipophility, their residues bioconcentrate in lipidrich tissues, according to the equilibrium pattern of internal transport and lipid tissue content. The studies on their role as estrogenic or antiandrogenic agents have related these pesticides to breast cancer. Therefore, organochlorine pesticides were determined in breast adipose tissue of women subjected to surgery due to the diagnosis of breast abnormalities. The study pool consti tuted 127 women with malignant breast tumors, 127 with benign breast tumors and 127 in a control group without breast abnormalities. The pesticides determined were: HCB, b HCH, pp'DDE, op'DDT, pp'DDT and SDDT. Comparing the studied groups, the highest residue levels were determined in the benign breast tumor group. The determined levels from the control group through malignant to benign cases increased stepwise; HCB: 0.045, 0.099, 0.116 mg kg 1 , bHCH: 0.163, 0.265, 0.319 mg kg 1 , pp'DDE: 0.782, 0.980, 1.761 mg kg 1 , op'DDT: 0.035, 0.094, 0.176 mg kg 1 , pp'DDT: 0.296, 0.351, 0.661 mg kg 1 , SDDT: 1.112, 1.423, 2.601 mg kg 1 , respectively. Paired analyses of the three groups revealed divergences among them and correlation of these pesticide levels with breast tumors. Calculated relative risk (RR) values for the benign to control group and the malignant to control cases presented the following values:

La isotretinoina es un retinoide sintetico utilizado en el tratamiento de diversas enfermedades d... more La isotretinoina es un retinoide sintetico utilizado en el tratamiento de diversas enfermedades dermatologicas, de las cuales la mas frecuente es el acne inflamatorio severo. Desde el inicio de su utilizacion se ha reportado un aumento de los casos de depresion e ideacion suicida en pacientes tratados con este medicamento, aunque no se ha determinado si se trata de una relacion directa con el medicamento o con la enfermedad de fondo en una poblacion especialmente susceptible. En esta revision se analiza la informacion mas reciente acerca de la posibilidad de una relacion directa entre el consumo de isotretinoina y el riesgo de intento de suicidio o suicidio consumado.

Revista Internacional De Contaminacion Ambiental, 2004

Revista Internacional De Contaminacion Ambiental Vol 20 No 4 185 192, Sep 13, 2011

Many papers describe the analytical methods for organochlorine pesticide residue determination in... more Many papers describe the analytical methods for organochlorine pesticide residue determination in environmental samples. Gas chromatography with electron capture detection requires an efficient clean-up step of extracts. To reach this purpose, the adsorbents such as florisil, aluminium oxide and silica gel are employed. Most of organochlorine pesticides are resistant to sulfuric acid, characteristic that was used in the destruction of organic compounds of sample origin. The analytical methods that use sulfuric acid as a clean-up medium during the determination of organochlorine pesticide residues in the following samples are described: soil and sediments, vegetables and tubercles, grains, straw, tobacco, fatty samples of animal origin such as adipose tissue and milk fat, blood serum and semen. The analytical quality study done for each sample type, expressed as mean with standard deviation and percent of variation, gave values higher than 90 % of recovery and a variation smaller than 10 %. According to the criteria of the Association of Official Analytical Chemists of USA, the obtained values considered the described methods as excellent in recovery and with acceptable variability. Moreover, the use of sulfuric acid makes the method cheap, eliminating the adsorbents and diminishing the volume of solvents.

Salud Pública de México, 1997

Carvajal O, Angulo O. Efecto de los ácidos grasos polinsaturados n-3 en el perfil lipídico de mex... more Carvajal O, Angulo O. Efecto de los ácidos grasos polinsaturados n-3 en el perfil lipídico de mexicanos voluntarios.

Nutrition Research, 2002

We examined clearance rates in serum of lymph lipids collected from rats fed a diet containing on... more We examined clearance rates in serum of lymph lipids collected from rats fed a diet containing one of four types of structured triglycerides containing linoleic and medium-chain fatty acids, 1) sn-1 (3) medium-chain fatty acids-sn-2 linoleic acid (MLM), 2) interesterified MLM (iMLM), 3) sn-2 mediumchain fatty acids-sn-1 (3) linoleic acid (LML), and 4) interesterified LML (iLML). Rats with permanent cannulation of thoracic duct were fed a diet containing one of the structured triglycerides and then, thoracic duct lymph was collected. The lymph was injected into the right superior vena cava in rats fed the same diet for a week. Half-life of triglyceride was significantly longer in rats injected the lymph originated from rats fed LML compared to the other groups. Half-life of retinyl palmitate, a marker of chylomicron remnant, tended to be longer in the LML group. These observations suggest that the structural differences in triglycerides containing medium-chain fatty acids and linoleic acid can alter the rate of lipid clearance in serum of rats.

Journal of the Science of Food and Agriculture, 2003

Honey is obtained from the hives of European honeybees. Honeybees can be infested by Varroa paras... more Honey is obtained from the hives of European honeybees. Honeybees can be infested by Varroa parasitism, which affects honey production. The acaricide τ-fluvalinate used in beehives to control Varroa mites, can leave its residues in honey, pollen and wax. A monitoring study was undertaken to determine the τ-fluvalinate residues in honey samples taken from treated hives. The τ-fluvalinate residues were determined by gas chromatography using a short, non-polar packed column with electron capture detection. Analysis of 50 samples showed an average residue level of 15 µg kg−1. The same samples were filtered through Whatman filter paper to separate the honey from residual suspended particles. The filtered honeys showed no acaricide residues above the detection limit of 3 µg kg −1, while the average residue level determined in the sediments was 392 µg kg −1. Thus the residues of τ-fluvalinate in honey can be eliminated by separating the honey from residual suspended particles that contain acaricide residues. Copyright © 2003 Society of Chemical Industry

Journal of Agricultural and Food Chemistry, 2004

The organochlorine pesticides are lipophilic and persistent and tend to accumulate in soils and g... more The organochlorine pesticides are lipophilic and persistent and tend to accumulate in soils and growing plants. The contamination of growing plants occurs by adhesion of volatile substances from the air to the plant surface and by the migration of contaminants through xylem in inner ascendant transport. Persistent organochlorine pesticides (HCB, alpha,gamma-HCH, pp'DDE, op'DDT, pp'DDT) levels were determined in soils and rye plants. The aims of the study were the monitoring of organochlorine pesticide concentrations and the comparison of these levels among soil, rye straw, and rye grains. Fifty soil samples and 50 rye plant (50 straw and 50 grains) samples were taken. The GLC-ECD chromatographic results indicated the following contamination levels distributed among soil, straw, and grains: HCB (0.7-1.2-0.7 microg.kg(-1)), alpha-HCH (0.6-3.4-1.2 microg.kg(-1)), gamma-HCH (1.8-27.3-4.4 microg.kg(-1)), Sigma-HCH (2.5-30.7-5.6 microg.kg(-1)), pp'DDE (1.0-7.8-5.5 microg.kg(-1)), op'DDT (16.1-20.4-17.0 microg.kg(-1)), pp'DDT (38.0-41.7-49.6 microg.kg(-1)), and Sigma-DDT (54.2-63.2-72.1 microg.kg(-1)). The study verified the presence of organochlorine pesticides in the Mexican agricultural environment and their migration from soil to the growing rye plants. However, DDT has been banned since 1999 for sanitary reasons, and Lindane is applied only in some cases as a seed dresser. The determined organochlorine pesticide levels in rye plants are low, at residual levels that are below Codex Alimentarius Commission maximum residue limits.

Bulletin of Environmental Contamination and Toxicology, 2005

Bulletin of Environmental Contamination and Toxicology, 2002

Bulletin of Environmental Contamination and Toxicology, 2004

Bulletin of Environmental Contamination and Toxicology, 2008

Agricultural cultivation assists organochlorine pesticide migration from contaminated soils to gr... more Agricultural cultivation assists organochlorine pesticide migration from contaminated soils to growing plants. This phenomenon is caused by retention processes that modify volatile pesticide exchange between soil, air and plants. The aim of the study was to monitor organochlorine pesticide (HCB, aand c-HCH, pp 0 DDE, op 0 DDT, pp 0 DDT) levels and compare these concentrations in soil, carrot roots and carrot leaves. Fifty soil samples, 50 carrot root and 50 carrot leaf samples were taken from the same fields and analyzed by GLC-ECD. The results reveal organochlorine pesticide diffusion from agricultural soils to growing carrot plants and their vapors adsorbtion by leaves. Within the carrot plant, organochlorine pesticides accumulate especially in carrot root peel, 3-7 times more than in root flesh.

Bulletin of Environmental Contamination and Toxicology, 2009

Breast milk is considered the most important route in the elimination of deposited organochlorine... more Breast milk is considered the most important route in the elimination of deposited organochlorine pesticides in a mother's body. The equilibrium of organochlorine pesticides in the human body considers the elements of internal transport processes, the equilibrium pattern between pesticides and tissue fat contents, and the mobilization of lipids and lipoproteins among body parts. The aim of this study was to determine organochlorine pesticide levels in breast milk samples from the 4th to the 30th day of lactation and the trend in their concentration time so as to forecast the time tendency of residue levels and the pesticide excretion pattern. Milk samples were taken from forty participants and analyzed by GLC-ECD. The organochlorine pesticide residues determined in the breast milk samples during lactation decreased: b-HCH from 0.095 to 0.066 mg/kg, pp 0 DDE from 1.807 to 1.423 mg/kg and pp 0 DDT from 0.528 to 0.405 mg/kg, at the characteristic rate for each compound. The obtained results compared with the calculated fits of forecasts were parallel and did not exhibit significant differences. The newborn baby exposed during lactation had organochlorine pesticide residues whose levels decreased permanently. The levels depended not only on the breast milk nutrition, but also on the total environmental exposures which included air pollution as a significant contamination source.

Bioscience, Biotechnology, and Biochemistry, 2000

Revista Internacional …, 2010

Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs a... more Organochlorine pesticides have been used in Mexico in agriculture, sanitation, malaria programs and livestock to combat ectoparasites. Due to their chemical stability, persis tence and lipophility, their residues bioconcentrate in lipidrich tissues, according to the equilibrium ...

Archives of Environmental Health: An International Journal, 2004

Samples of human blood sera (N = 118) for the determination of organochlorine pesticide levels we... more Samples of human blood sera (N = 118) for the determination of organochlorine pesticide levels were obtained at autopsy from auto accident victims in Veracruz, Mexico, during the years 2000 and 2001. The presence of hexachlorobenzene (HCH), beta-hexachlorocyclohexane (beta-HCH), 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDT), and o,p'-DDT was confirmed by gas-liquid-electron-capture detection chromatography. During the years 2000 and 2001, the respective mean levels of (a) HCB, (b) beta-HCH, (c) p,p'-DDE, (d) o,p'-DDT, (e) p,p'-DDT, and (f) total DDT were (a) 2.1 ng/ml and 1.4 ng/ml, (b) 3.0 ng/ml and 3.6 ng/ml, (c) 21.1 ng/ml and 23.8 ng/ml, (d) 1.2 ng/ml and 0.8 ng/ml, (e) 3.3 ng/ml and 2.5 ng/ml, and, finally, (f) 25.4 ng/ml and 27.1 ng/ml, respectively. High levels of persistent organochlorine pesticides were--and continue to be--present in the blood of individuals who live in Mexico. Levels of insecticide metabolites (e.g., beta-HCH, p,p'-DDE) in blood have increased during recent years (1997-2001), but levels of p,p'-DDT decreased in 2001 because the use of DDT for the control of malaria in Mexico was restricted.

How to cite Complete issue More information about this article Journal's homepage in redalyc.org ... more How to cite Complete issue More information about this article Journal's homepage in redalyc.org Scientific Information System Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Non-profit academic project, developed under the open access initiative