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Toxic risk by the use of pesticides
Abstracts / Toxicology Letters 259S (2016) S73–S247
PP23.23 Toxic risk by the use of pesticides I. Santiago Roque 1 , A.L. Rendón Ramírez 2 , S.L. González Herrera 1 , C. Tapia Pale 1 , L. Rosas Silva 1 , M.F. Hernández Caro 1 , J.C. Álvarez Alonso 1 , S.A. Landa Hernández 1 , J.A. Palma Jacinto 1 , Z.J. Flores López 1 1 Neurotoxicology Laboratory UV-CA-379. FRHQS Facultad de Bioanálisis. Universidad Veracruzana, Xalapa, Veracruz, Mexico 2 University Country Vasco Adela Rendón PHD Biophysics Unit (CSIC-UPV/EHU) Fundación Biofisíca Bizkaia, Spain
Introduction: Pesticide intoxication still remains as a general problem of public health. According to the National Epidemiological Bulletin of Mexico until the week 17th of 2016, 959 cases were reported in the country since 2015, Veracruz state ranks fifth in frequency with 6.5% (n = 63). These data do not reflect the total number of workers acutely intoxicated by pesticides; not all cases are reported, generally because patients are located away from the health centers. These intoxications are generally attributable to inadequate use of clothing or equipment, improper preparation, breach of the relevant rules and lack of expert management supervision. In addition, some pesticides present high toxicity, and some of them are prohibited in other countries, and there are bad practices for the final destination of agrochemical containers. These situations may happen in the community of Teocelo, Veracruz, Mexico, where most of the population are farmers. Objective: To identify the agriculture practices related to the use of pesticides. Materials and methods: A prospective cohort transversal study was conducted, for which a survey was applied to the population of the communities of Texin, Llano Grande, Loma Alta and Monte Blanco that conform the Teocelo’s municipality of Veracruz. The variables included were: (A) Type of activity; the surveyed population were asked to provide information about the types of pesticides used during the last working year. (B) If the farmers had presented a pesticide poisoning. (C) Type of personal protection equipment used when using pesticides. (D) The handling and final destination of pesticide residues and containers. Results: A total of 1573 individuals were surveyed, 23% (n = 362) was dedicated to agriculture, 72% (n = 261) referred using some agrochemicals in agriculture, 17.4% from 23% presented symptoms of pesticide intoxication. Anyone used to wear protection clothes in theirs agricultural activities. Any farmer knew the correct procedures in handling the pesticide residues, neither the way to eliminate these empty containers, which generates a secondary source of pollution. The most commonly used compounds were: 20% organochlorines such as dicamba (dimethylamine salt of 3,6-dichloro-2-methoxybenzoic acid) and ametrine. While cypermethrin, glyphosate-isopropylamine salt of N-(phosphonomethyl) glycine, a mixture of chlorpyrifos (OPs) and permethrin (pyrethroid), and the bipyridyl, paraquat reached 80%. Conclusion: Most of pesticides used by farmers are represented by organophosphate herbicides, fungicides and insecticides, carbamates and organochlorines; and farmers did not follow protective measures such as wearing appropriate clothing and footwear and handling the correct pesticide doses, which leads to a toxic risk. Perspectives: To evaluate biomarkers, quantity of pesticides and metabolites to identify the exposure to these substances in vulnerable populations such as children, pregnant women and occupationally exposed populations, to raise intervention strategies and prevent poisonings by pesticides.
S225
Acknowledgement: Students of the Toxicology Section, NRC: 52343, 38479, 38478, who help in the survey. Comprehensive Program of Institutional Strengthening, PIFI 2014. http://dx.doi.org/10.1016/j.toxlet.2016.07.540 PP23.24 Removal of pentachlorophenol using chayote (Sechium edule Sw) peroxidase A.I.A. Alonso 1 , E. Chávez 1 , D. Polo 1 , E. Ayala 1 , E. Vidal 1 , G. Salazar 2 1
Facultad de Ingeniería Química de la Benemérita Universidad Autónoma de Puebla, Mexico 2 Tecnológico de Monterrey Campus Puebla, Mexico Introduction: The pentachlorophenol (PCP) is a highly toxic and persistent halogenated hydrocarbon pesticide used for preserving wood against fungi, bacteria and insects. The PCP has serious long-term effects, its mutagenic and can cause alterations in the immune and endocrine system. It is possible to remove this contaminant by oxidoreductases such as peroxidases extracted from chayote (Sechium edule Sw), whose mechanism of action by oxidation generates free radicals which then are polymerized to low toxicity products. Objective: To polymerize pentachlorophenol using chayote peroxidase to remove the oxidation products. Methods: Two samples were prepared with 150 and 200 ppm of PCP diluted in 10 ml of distilled water. These solutions were then tested for the transformation of pentachlorophenol in their reaction products by adding 2.5 ml of each of the solutions in a quartz cell and then adding 10 l of chayote peroxidase and 10 l of 0.0123 M H2 O2 sequentially. An UV–Vis spectra was obtained using a range of wavelengths ranging from 250 to 700 nm with a Cary 50 Varian equipment until no change in absorption, shape or position of the spectroscopic bands were observed. Then the samples were kept for 24 h and centrifuged at 8500 rpm for 10 min to separate the solid phase from the supernatant, which then was measured at 500 nm to determine the percentage of removal of the products formed. Results: The water prepared with PCP at the different concentrations was initially colorless, this was confirmed by observing a strong absorbance with a wavelength of 315 nm, which falls within the UV region of the spectra. When 20 L of enzyme and 20 L of H2 O2 were added to the sample, a gradual change of color to yellow was observed and insoluble reaction products were formed; from these products, 90% of them could be removed by centrifugation. Conclusions: Oxidation products of pentachlorophenol were removed by a chayote peroxidase, a mesoamerican fruit used exclusively for food. There have been reports of horseradish peroxidases and fungi peroxidases, which oxidize PCP to quinone-type polymeric products that are less toxic. http://dx.doi.org/10.1016/j.toxlet.2016.07.541
PP23.23 Toxic risk by the use of pesticides I. Santiago Roque 1 , A.L. Rendón Ramírez 2 , S.L. González Herrera 1 , C. Tapia Pale 1 , L. Rosas Silva 1 , M.F. Hernández Caro 1 , J.C. Álvarez Alonso 1 , S.A. Landa Hernández 1 , J.A. Palma Jacinto 1 , Z.J. Flores López 1 1 Neurotoxicology Laboratory UV-CA-379. FRHQS Facultad de Bioanálisis. Universidad Veracruzana, Xalapa, Veracruz, Mexico 2 University Country Vasco Adela Rendón PHD Biophysics Unit (CSIC-UPV/EHU) Fundación Biofisíca Bizkaia, Spain
Introduction: Pesticide intoxication still remains as a general problem of public health. According to the National Epidemiological Bulletin of Mexico until the week 17th of 2016, 959 cases were reported in the country since 2015, Veracruz state ranks fifth in frequency with 6.5% (n = 63). These data do not reflect the total number of workers acutely intoxicated by pesticides; not all cases are reported, generally because patients are located away from the health centers. These intoxications are generally attributable to inadequate use of clothing or equipment, improper preparation, breach of the relevant rules and lack of expert management supervision. In addition, some pesticides present high toxicity, and some of them are prohibited in other countries, and there are bad practices for the final destination of agrochemical containers. These situations may happen in the community of Teocelo, Veracruz, Mexico, where most of the population are farmers. Objective: To identify the agriculture practices related to the use of pesticides. Materials and methods: A prospective cohort transversal study was conducted, for which a survey was applied to the population of the communities of Texin, Llano Grande, Loma Alta and Monte Blanco that conform the Teocelo’s municipality of Veracruz. The variables included were: (A) Type of activity; the surveyed population were asked to provide information about the types of pesticides used during the last working year. (B) If the farmers had presented a pesticide poisoning. (C) Type of personal protection equipment used when using pesticides. (D) The handling and final destination of pesticide residues and containers. Results: A total of 1573 individuals were surveyed, 23% (n = 362) was dedicated to agriculture, 72% (n = 261) referred using some agrochemicals in agriculture, 17.4% from 23% presented symptoms of pesticide intoxication. Anyone used to wear protection clothes in theirs agricultural activities. Any farmer knew the correct procedures in handling the pesticide residues, neither the way to eliminate these empty containers, which generates a secondary source of pollution. The most commonly used compounds were: 20% organochlorines such as dicamba (dimethylamine salt of 3,6-dichloro-2-methoxybenzoic acid) and ametrine. While cypermethrin, glyphosate-isopropylamine salt of N-(phosphonomethyl) glycine, a mixture of chlorpyrifos (OPs) and permethrin (pyrethroid), and the bipyridyl, paraquat reached 80%. Conclusion: Most of pesticides used by farmers are represented by organophosphate herbicides, fungicides and insecticides, carbamates and organochlorines; and farmers did not follow protective measures such as wearing appropriate clothing and footwear and handling the correct pesticide doses, which leads to a toxic risk. Perspectives: To evaluate biomarkers, quantity of pesticides and metabolites to identify the exposure to these substances in vulnerable populations such as children, pregnant women and occupationally exposed populations, to raise intervention strategies and prevent poisonings by pesticides.
S225
Acknowledgement: Students of the Toxicology Section, NRC: 52343, 38479, 38478, who help in the survey. Comprehensive Program of Institutional Strengthening, PIFI 2014. http://dx.doi.org/10.1016/j.toxlet.2016.07.540 PP23.24 Removal of pentachlorophenol using chayote (Sechium edule Sw) peroxidase A.I.A. Alonso 1 , E. Chávez 1 , D. Polo 1 , E. Ayala 1 , E. Vidal 1 , G. Salazar 2 1
Facultad de Ingeniería Química de la Benemérita Universidad Autónoma de Puebla, Mexico 2 Tecnológico de Monterrey Campus Puebla, Mexico Introduction: The pentachlorophenol (PCP) is a highly toxic and persistent halogenated hydrocarbon pesticide used for preserving wood against fungi, bacteria and insects. The PCP has serious long-term effects, its mutagenic and can cause alterations in the immune and endocrine system. It is possible to remove this contaminant by oxidoreductases such as peroxidases extracted from chayote (Sechium edule Sw), whose mechanism of action by oxidation generates free radicals which then are polymerized to low toxicity products. Objective: To polymerize pentachlorophenol using chayote peroxidase to remove the oxidation products. Methods: Two samples were prepared with 150 and 200 ppm of PCP diluted in 10 ml of distilled water. These solutions were then tested for the transformation of pentachlorophenol in their reaction products by adding 2.5 ml of each of the solutions in a quartz cell and then adding 10 l of chayote peroxidase and 10 l of 0.0123 M H2 O2 sequentially. An UV–Vis spectra was obtained using a range of wavelengths ranging from 250 to 700 nm with a Cary 50 Varian equipment until no change in absorption, shape or position of the spectroscopic bands were observed. Then the samples were kept for 24 h and centrifuged at 8500 rpm for 10 min to separate the solid phase from the supernatant, which then was measured at 500 nm to determine the percentage of removal of the products formed. Results: The water prepared with PCP at the different concentrations was initially colorless, this was confirmed by observing a strong absorbance with a wavelength of 315 nm, which falls within the UV region of the spectra. When 20 L of enzyme and 20 L of H2 O2 were added to the sample, a gradual change of color to yellow was observed and insoluble reaction products were formed; from these products, 90% of them could be removed by centrifugation. Conclusions: Oxidation products of pentachlorophenol were removed by a chayote peroxidase, a mesoamerican fruit used exclusively for food. There have been reports of horseradish peroxidases and fungi peroxidases, which oxidize PCP to quinone-type polymeric products that are less toxic. http://dx.doi.org/10.1016/j.toxlet.2016.07.541