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1.
Anal Methods ; 16(27): 4539-4550, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38910531

RESUMEN

Dithiocarbamates are a class of fungicides widely used in many countries. In this study, methods for determining the ethylene-bis-dithiocarbamate (EBDC) subclass, and their degradation product ethylenethiourea (ETU) were validated by UHPLC-MS/MS in different types of dry herbs, which can be used as food and/or medicinal purposes. Mancozeb was used in the validation of the EBDC method, where it was initially complexed with EDTA, derivatized, extracted with dimethyl sulfate in acetonitrile, magnesium sulfate (MgSO4), and sodium chloride (NaCl), and then purified using primary secondary amine (PSA). In the ETU method, L-cysteine hydrochloride monohydrate was added to the samples before extraction with acetonitrile, MgSO4, and NaCl, followed by purification with PSA. A pesticide-free blend of seven herbs (boldo, artichoke, "espinheira-santa", cat's claw, senna, chamomile, and cascara buckthorn) comprising distinct parts of the plants (leaves, bark, flowers and/or stems) was used as a control for method validation. Recoveries ranged from 79 to 113% for EBDC and 81 to 109% for ETU. Repeatability and intermediate precision were <20% for both methods. The limit of quantification was 0.03 mg kg-1 for EBDC (0.02 mg kg-1 of CS2) and ETU. The limit of detection (LOD) was set at 1/3 of the LOQ (0.01 mg kg-1 for both analytes). In total, 103 samples of 33 different dry herbs were analyzed, of which 19.4% were positive for EBDC (≥LOD), but no ETU residues were found in any of the analyzed samples. Given the absence of registered dithiocarbamates for use in the investigated herbs in Brazil, the positive results suggest potential illegal pesticide use or cross-contamination, especially considering the low concentrations detected in most samples. Although exposure to EBDC through the consumption of medicinal herbs from positive samples did not indicate a health risk to consumers, these plants must be monitored to prevent illicit pesticide usage, particularly when the herbs are intended for therapeutic purposes.


Asunto(s)
Etilenotiourea , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Etilenotiourea/análisis , Etilenotiourea/química , Fungicidas Industriales/análisis , Fungicidas Industriales/química , Etilenobis(ditiocarbamatos)/química , Etilenobis(ditiocarbamatos)/análisis , Límite de Detección , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Reproducibilidad de los Resultados , Plantas Medicinales/química
2.
Biol Res ; 52(1): 27, 2019 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-31054579

RESUMEN

BACKGROUND: To assess the expression of T-box transcription factor 4 (TBX4) during the anorectal development in normal and ethylenethiourea (ETU)-induced anorectal malformations (ARM) rat embryos. METHODS: Anorectal malformations was induced by ETU on the 10th gestational day (E10) in rat embryos. Spatio-temporal expression of TBX4 was evaluated in normal (n = 490) and ETU-induced ARM rat embryos (n = 455) from E13 to E16 by immunohistochemical staining, Western blot analysis and real-time RT-PCR. RESULTS: In the normal embryos, immunohistochemical staining revealed that TBX4 expression was detected in the epithelium of hindgut and urorectal septum (URS) on E13. TBX4-immunopositive cells were increased significantly in the epithelium of hindgut and URS, the future anal orifice part of cloacal membrane on E14. On E15, abundant stained cells were observed in the rectum, URS and dorsal cloacal membrane and the expression of positive cells reached its peak. On E16, only sporadic positive cells were distributed in the epithelium of the distal rectum. In the ARM embryos, the hindgut/rectum, URS and dorsal cloacal membrane were faint for TBX4 immunohistochemical staining. In the normal group, TBX4 protein and mRNA expression showed time-dependent changes in the hindgut/rectum from E13 to E16 on Western blot and real-time RT-PCR. On E13 and E15, the expression level of TBX4 mRNA in the ARM group was significantly lower than that in the normal group (P < 0.05). On E15, the expression level of TBX4 protein in the ARM group was significantly lower than that in the normal group (P < 0.05). CONCLUSIONS: The expression of TBX4 was downregulated in ETU-induced ARM embryos, which may play important roles in the pathogenesis of anorectal development.


Asunto(s)
Malformaciones Anorrectales/genética , Etilenotiourea/farmacología , Regulación de la Expresión Génica/genética , Proteínas de Dominio T Box/genética , Animales , Malformaciones Anorrectales/inducido químicamente , Western Blotting , Femenino , Inmunohistoquímica , Embarazo , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteínas de Dominio T Box/metabolismo
3.
Environ Sci Pollut Res Int ; 26(5): 4498-4509, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29943251

RESUMEN

Ethylenethiourea (ETU) is a toxic degradation product of one class of fungicide which is largely employed in the world, the ethylenebisdithiocarbamates. In this study, ETU was degraded by ozonation enhanced by UV-C light irradiation (O3/UV-C) in aqueous medium. Degradation experiments were conducted at natural pH (6.8) and neutral pH (7.0, buffered). ETU was promptly eliminated from the reactive medium during ozonation in the presence and absence of light. Within the first few minutes of reaction conducted in natural pH, the pH decreased quickly from 6.8 to 3.0. Results show that ETU mineralization occurs only in the reaction conducted in neutral pH and that it takes place in a higher rate when enhanced by UV-C irradiation. Main intermediates formed during the O3/UV-C experiments in different conditions tested were also investigated and three different degradation mechanisms were proposed considering the occurrence of direct and indirect ozone reactions. At pH 7, ethylene urea (EU) was quickly generated and degraded. Meanwhile, at natural pH, besides EU, other compounds originated from the electrophilic attack of ozone to the sulfur atom present in the contaminant molecule were also identified during reaction and EU was detected within 60 min of reaction. Results showed that ozonation enhanced by UV-C promotes a faster reaction than the same system in the absence of light, and investigation of the toxicity is recommended.


Asunto(s)
Etilenotiourea/química , Ozono/química , Contaminantes Químicos del Agua/química , Cromatografía Líquida de Alta Presión/métodos , Fungicidas Industriales/química , Concentración de Iones de Hidrógeno , Imidazolidinas/química , Espectrometría de Masas/métodos , Oxidación-Reducción , Rayos Ultravioleta , Agua/química , Purificación del Agua/métodos
4.
Biol. Res ; 52: 27, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1011429

RESUMEN

BACKGROUND: To assess the expression of T-box transcription factor 4 (TBX4) during the anorectal development in normal and ethylenethiourea (ETU)-induced anorectal malformations (ARM) rat embryos. METHODS: Anorectal malformations was induced by ETU on the 10th gestational day (E10) in rat embryos. Spatiotemporal expression of TBX4 was evaluated in normal (n = 490) and ETU-induced ARM rat embryos (n = 455) from E13 to E16 by immunohistochemical staining, Western blot analysis and real-time RT-PCR. RESULTS: In the normal embryos, immunohistochemical staining revealed that TBX4 expression was detected in the epithelium of hindgut and urorectal septum (URS) on E13. TBX4-immunopositive cells were increased significantly in the epithelium of hindgut and URS, the future anal orifice part of cloacal membrane on E14. On E15, abundant stained cells were observed in the rectum, URS and dorsal cloacal membrane and the expression of positive cells reached its peak. On E16, only sporadic positive cells were distributed in the epithelium of the distal rectum. In the ARM embryos, the hindgut/rectum, URS and dorsal cloacal membrane were faint for TBX4 immunohistochemical staining. In the normal group, TBX4 protein and mRNA expression showed time-dependent changes in the hindgut/rectum from E13 to E16 on Western blot and real-time RT-PCR. On E13 and E15, the expression level of TBX4 mRNA in the ARM group was significantly lower than that in the normal group (P < 0.05). On E15, the expression level of TBX4 protein in the ARM group was significantly lower than that in the normal group (P < 0.05). CONCLUSIONS: The expression of TBX4 was downregulated in ETU-induced ARM embryos, which may play important roles in the pathogenesis of anorectal development.


Asunto(s)
Animales , Femenino , Embarazo , Ratas , Regulación de la Expresión Génica/genética , Proteínas de Dominio T Box/genética , Etilenotiourea/farmacología , Malformaciones Anorrectales/genética , Inmunohistoquímica , Western Blotting , Ratas Wistar , Proteínas de Dominio T Box/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Malformaciones Anorrectales/inducido químicamente
5.
Environ Health Perspect ; 126(5): 057007, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29847083

RESUMEN

BACKGROUND: Although growing evidence suggests that early-life excess manganese (Mn) impairs neurodevelopment, data on the neurodevelopmental effects of mancozeb, a fungicide containing Mn, and its main metabolite ethylenethiourea (ETU) are limited. OBJECTIVE: We examined whether prenatal mancozeb exposure and excess Mn were associated with neurodevelopment in 355 1-y-old infants living near banana plantations with frequent aerial mancozeb spraying in Costa Rica. METHODS: We measured urinary ETU, hair Mn, and blood Mn concentrations in samples collected 1-3 times during pregnancy from mothers enrolled in the Infants' Environmental Health (ISA) study. We then assessed neurodevelopment in their 1-y-old infants using the Bayley Scales of Infant and Toddler Development, 3rd edition (BSID-III). We estimated exposure-outcome associations using linear regression models adjusted for maternal education, parity, gestational age at birth, child age, Home Observation for Measurement of the Environment score, and location of neurodevelopmental assessment. RESULTS: Median (P25-P75) urinary ETU, hair Mn, and blood Mn measured during pregnancy were 3.3 µg/L (2.4-4.9; specific gravity-corrected), 1.7 µg/g (0.9-4.1), and 24.0 µg/L (20.3-28.0), respectively. Among girls, higher ETU was associated with lower social-emotional scores [ß per 10-fold increase=-7.4 points (95% CI: -15.2, 0.4)], whereas higher hair Mn was associated with lower cognitive scores [-3.0 (-6.1, 0.1)]. Among boys, higher hair Mn was associated with lower social-emotional scores [-4.6 (-8.5, -0.8)]. We observed null associations for blood Mn, language, and motor outcomes. CONCLUSIONS: Our findings indicate that maternal exposure to mancozeb and excess Mn during pregnancy may have adverse and sex-specific effects on infant neurodevelopment. https://doi.org/10.1289/EHP1955.


Asunto(s)
Salud Ambiental/métodos , Maneb/toxicidad , Manganeso/toxicidad , Zineb/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Etilenotiourea/toxicidad , Femenino , Fungicidas Industriales/toxicidad , Humanos , Lactante , Masculino , Exposición Materna/efectos adversos , Trastornos del Neurodesarrollo/inducido químicamente , Trastornos del Neurodesarrollo/epidemiología , Embarazo
6.
Acta toxicol. argent ; 24(3): 180-186, dic. 2016. ilus, tab
Artículo en Español | LILACS | ID: biblio-837864

RESUMEN

El Zineb es un plaguicida perteneciente a la familia de los etilenbisditiocarbamatos (EBDC) ampliamente utilizado en la provincia de Jujuy (Argentina). La toxicidad de este fungicida está dada por la etilentiourea (ETU) que es el principal producto de su degradación. La ETU tiene efectos mutagénicos, teratogénicos y cancerígenos en animales. La EPA la clasifica como probable cancerígeno humano. El objetivo del trabajo fue determinar la transformación del Zineb a ETU en acelgas cultivadas en Jujuy, por efecto del calor húmedo por tratamiento térmico. El método se basó en la extracción de la ETU con agua y su posterior reextracción con diclorometano a pH alcalino. El extracto se purificó por cromatografía en columna de alúmina y la ETU se cuantificó por HPLC con un detector UV-Visible a 232 nm. Para cumplir con el objetivo planteado se realizó un cultivo experimental de acelgas a las que se aplicó el fungicida Zineb, el cual luego se cuantificó a diferentes periodos de tiempo. La ETU se cuantificó con y sin aplicación de calor húmedo. La concentración de ETU en las acelgas sometidas a tratamiento térmico fue de 8,07 mg/kg y transcurridos 30 días disminuyó a 0,05 mg/kg, lo que representa una disminución de más del 99 % respecto a la concentración inicial. Simultáneamente, se determinó la concentración de Zineb en las acelgas y se obtuvo, inicialmente, 44 mg/kg y luego de 36 días la concentración de Zineb disminuyó a 3,83 mg/kg, lo que representa una disminución del 91 % respecto a la concentración del plaguicida al inicio. La detección de ETU en acelgas sometidas a tratamientos térmicos confirma la transformación del fungicida Zineb a un producto de degradación clasificado según el IARC en el grupo 3. Esto pone en discusión la reglamentación Argentina vigente, por cuanto al finalizar los tiempos de carencia no se evalúan la presencia de metabolitos o productos de degradación potencialmente tóxicos.


Zineb is a pesticide belonging to the family of ethylenebisdithiocarbamates (EBDC) widely used in the province of Jujuy, Argentina. The toxicity of this fungicide is given by the ethylenethiourea (ETU) which is the main product of degradation. The ETU has mutagenic, teratogenic and carcinogenic effects in animals. The EPA classifies it as a probable human carcinogen. The aim of the study was to determine the transformation of Zineb to ETU in cultivated chards in Jujuy, by treatment with humid heat. The method is based on extraction of ETU with water and subsequent extraction of the aqueous phase with dichloromethane. The extract was cleaned by alumina column chromatography and the ETU was quantified by HPLC with a UV-Visible detector at 232 nm. An experimental cultivation of chards was carried out and the Zineb fungicide was applied and then quantified at different time periods. The ETU was quantified with and without application of moist heat. The concentration of ETU in heat treated chards was 8.07 mg/kg and after 30 days decreased to 0.05 mg/kg, representing a decrease of more than 99 % over the initial concentration. Simultaneously, Zineb concentration in chard was initially determined as 44 mg/kg and, 36 days later, the Zineb concentration decreased to 3.83 mg/kg, representing a 91% decrease with respect to the concentration of the pesticide at the beginning. Detection of ETU in chards subjected to heat treatment confirms the transformation of the fungicide Zineb to a degradation product classified by the IARC as group 3. This puts into discussion the current Argentine regulations since, at the end of the deficiency times the presence of potentially toxic metabolites or degradation products is not evaluated.


Asunto(s)
Humanos , Beta vulgaris , Etilenotiourea/toxicidad , Tratamiento Térmico/efectos adversos , Zineb/toxicidad , Argentina/epidemiología , Biodegradación Ambiental
7.
Environ Pollut ; 215: 247-257, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27208757

RESUMEN

Elevated manganese (Mn) in drinking water has been reported worldwide. While, naturally occurring Mn in groundwater is generally the major source, anthropogenic contamination by Mn-containing fungicides such as mancozeb may also occur. The main objective of this study was to examine factors associated with Mn and ethylenethiourea (ETU), a degradation product of mancozeb, in drinking water samples from villages situated near banana plantations with aerial spraying of mancozeb. Drinking water samples (n = 126) were obtained from 124 homes of women participating in the Infants' Environmental Health Study (ISA, for its acronym in Spanish), living nearby large-scale banana plantations. Concentrations of Mn, iron (Fe), arsenic (As), lead (Pb), cadmium (Cd) and ethylenethiourea (ETU), a degradation product of mancozeb, were measured in water samples. Only six percent of samples had detectable ETU concentrations (limit of detection (LOD) = 0.15 µg/L), whereas 94% of the samples had detectable Mn (LOD = 0.05 µg/L). Mn concentrations were higher than 100 and 500 µg/L in 22% and 7% of the samples, respectively. Mn was highest in samples from private and banana farm wells. Distance from a banana plantation was inversely associated with Mn concentrations, with a 61.5% decrease (95% CI: -97.0, -26.0) in Mn concentrations for each km increase in distance. Mn concentrations in water transported with trucks from one village to another were almost 1000 times higher than Mn in water obtained from taps in houses supplied by the same well but not transported, indicating environmental Mn contamination. Elevated Mn in drinking water may be partly explained by aerial spraying of mancozeb; however, naturally occurring Mn in groundwater, and intensive agriculture may also contribute. Drinking water risk assessment for mancozeb should consider Mn as a health hazard. The findings of this study evidence the need for health-based World Health Organization (WHO) guidelines on Mn in drinking water.


Asunto(s)
Contaminantes Atmosféricos/análisis , Agua Potable/análisis , Etilenotiourea/análisis , Fungicidas Industriales/análisis , Maneb/análisis , Manganeso/análisis , Zineb/análisis , Adulto , Factores de Edad , Agricultura , Costa Rica , Salud Ambiental , Monitoreo del Ambiente , Femenino , Humanos , Musa , Factores Socioeconómicos , Adulto Joven
8.
Arch Environ Occup Health ; 71(1): 3-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-24972111

RESUMEN

This study describes the use of pesticides mixtures and their potential association with comet assay results in 223 rice field workers in Colombia. Thirty-one pesticides were quantified in blood, serum, and urine (15 organochlorines, 10 organophosphorus, 5 carbamates, and ethylenethiourea), and the comet assay was performed. Twenty-four (77.42%) pesticides were present in the workers. The use of the maximum-likelihood factor analysis identified 8 different mixtures. Afterwards, robust regressions were used to explore associations between the factors identified and the comet assay. Two groups of mixtures--α-benzene hexachloride (α-BHC), hexachlorobenzene (HCB), and ß-BHC (ß: 1.21, 95% confidence interval [CI]: 0.33-2.10) and pirimiphos-methyl, malathion, bromophos-methyl, and bromophos-ethyl (ß: 11.97, 95% CI: 2.34-21.60)--were associated with a higher percentage of DNA damage and comet tail length, respectively. The findings suggest that exposure to pesticides varies greatly among rice field workers.


Asunto(s)
Agricultura , Daño del ADN/efectos de los fármacos , Exposición Profesional/efectos adversos , Oryza , Plaguicidas/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carbamatos/efectos adversos , Carbamatos/análisis , Colombia , Ensayo Cometa , Estudios Transversales , Etilenotiourea/efectos adversos , Etilenotiourea/análisis , Femenino , Humanos , Hidrocarburos Clorados/efectos adversos , Hidrocarburos Clorados/análisis , Masculino , Persona de Mediana Edad , Exposición Profesional/análisis , Compuestos Organofosforados/efectos adversos , Compuestos Organofosforados/análisis , Plaguicidas/sangre , Adulto Joven
9.
Acta Cir Bras ; 30(8): 517-22, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26352330

RESUMEN

PURPOSE: To investigate the effect of folic acid (FA) in an experimental model of anorectal malformations (ARMs) ethylenethiourea (ETU) induced. METHODS: Eight female Wistar rats were divided randomly in two groups. Group A - ETU; Group B - FA+ETU; Dams from group B received daily, since two weeks before pregnancy to the end of pregnancy, FA (50mg/kg) by gavage. Dams from groups A and B, received 1% ETU (125 mk/kg) by gavage on gestational day (GD) 11. Their fetuses were harvested by cesarean section on GD21 and were examined looking for ARMs. The thickness of anal stratified squamous epithelium (ASSE) and intestinal epithelium (IE) were analyzed. p < 0.05*. RESULTS: One hundred and one embryos were harvested. The number of embryos; number of ARMs; mean statistical % (± SD) were determined to be, respectively: ETU - 49 [30;65% (± 24%)] versus FA+ETU - 52 [1;02% (± 3%)] (p = 0.025). AMRs were significantly lower in FA+ETU group than in ETU group (p = 0.025). The thickness (µm) of ASSE (± SD) and IE (± SD) were measured, respectively: ETU - [27.75 (± 0.56) and 18.88 (± 0.93)] versus FA+ETU - [28.88 (± 0.61) and 21.11 (± 0.16)] (p = 0.001). The thickness of IE was significantly enlarged when FA was given (p=0.001). CONCLUSION: Folic acid reduces the number and enlarged the IE of ARMs ETU-induced.


Asunto(s)
Ano Imperforado/prevención & control , Ácido Fólico/uso terapéutico , Complejo Vitamínico B/uso terapéutico , Canal Anal/anomalías , Canal Anal/embriología , Animales , Malformaciones Anorrectales , Ano Imperforado/inducido químicamente , Modelos Animales de Enfermedad , Etilenotiourea , Femenino , Feto/anomalías , Embarazo , Distribución Aleatoria , Ratas Wistar , Recto/anomalías , Recto/embriología , Reproducibilidad de los Resultados
10.
Acta cir. bras ; Acta cir. bras;30(8): 517-522, Aug. 2015. tab, ilus
Artículo en Inglés | LILACS | ID: lil-757983

RESUMEN

PURPOSE: To investigate the effect of folic acid (FA) in an experimental model of anorectal malformations (ARMs) ethylenethiourea (ETU) induced.METHODS:Eight female Wistar rats were divided randomly in two groups. Group A - ETU; Group B - FA+ETU; Dams from group B received daily, since two weeks before pregnancy to the end of pregnancy, FA (50mg/kg) by gavage. Dams from groups A and B, received 1% ETU (125mk/kg) by gavage on gestational day (GD) 11. Their fetuses were harvested by cesarean section on GD21 and were examined looking for ARMs. The thickness of anal stratified squamous epithelium (ASSE) and intestinal epithelium (IE) were analyzed. p<0.05*.RESULTS:One hundred and one embryos were harvested. The number of embryos; number of ARMs; mean statistical % (± SD) were determined to be, respectively: ETU - 49 [30;65% (±24%)] versus FA+ETU - 52 [1;02% (±3%)] (p=0.025). AMRs were significantly lower in FA+ETU group than in ETU group (p=0.025). The thickness (µm) of ASSE (± SD) and IE (± SD) were measured, respectively: ETU - [27.75 (±0.56) and 18.88 (±0.93)] versus FA+ETU - [28.88 (±0.61) and 21.11 (±0.16)] (p=0.001). The thickness of IE was significantly enlarged when FA was given (p=0.001).CONCLUSION:Folic acid reduces the number and enlarged the IE of ARMs ETU-induced.


Asunto(s)
Animales , Femenino , Embarazo , Ano Imperforado/prevención & control , Ácido Fólico/uso terapéutico , Complejo Vitamínico B/uso terapéutico , Canal Anal/anomalías , Canal Anal/embriología , Ano Imperforado/inducido químicamente , Modelos Animales de Enfermedad , Etilenotiourea , Feto/anomalías , Distribución Aleatoria , Ratas Wistar , Reproducibilidad de los Resultados , Recto/anomalías , Recto/embriología
11.
Acta cir. bras. ; 30(8): 517-522, Aug. 2015. tab, ilus
Artículo en Inglés | VETINDEX | ID: vti-334082

RESUMEN

To investigate the effect of folic acid (FA) in an experimental model of anorectal malformations (ARMs) ethylenethiourea (ETU) induced. Eight female Wistar rats were divided randomly in two groups. Group A - ETU; Group B - FA+ETU; Dams from group B received daily, since two weeks before pregnancy to the end of pregnancy, FA (50mg/kg) by gavage. Dams from groups A and B, received 1% ETU (125mk/kg) by gavage on gestational day (GD) 11. Their fetuses were harvested by cesarean section on GD21 and were examined looking for ARMs. The thickness of anal stratified squamous epithelium (ASSE) and intestinal epithelium (IE) were analyzed. p<0.05*. One hundred and one embryos were harvested. The number of embryos; number of ARMs; mean statistical % (± SD) were determined to be, respectively: ETU - 49 [30;65% (±24%)] versus FA+ETU - 52 [1;02% (±3%)] (p=0.025). AMRs were significantly lower in FA+ETU group than in ETU group (p=0.025). The thickness (µm) of ASSE (± SD) and IE (± SD) were measured, respectively: ETU - [27.75 (±0.56) and 18.88 (±0.93)] versus FA+ETU - [28.88 (±0.61) and 21.11 (±0.16)] (p=0.001). The thickness of IE was significantly enlarged when FA was given (p=0.001). Folic acid reduces the number and enlarged the IE of ARMs ETU-induced.(AU)


Asunto(s)
Animales , Femenino , Embarazo , Ano Imperforado/prevención & control , Ácido Fólico/uso terapéutico , Complejo Vitamínico B/uso terapéutico , Canal Anal/anomalías , Canal Anal/embriología , Ano Imperforado/inducido químicamente , Modelos Animales de Enfermedad , Etilenotiourea , Feto/anomalías , Distribución Aleatoria , Ratas Wistar , Recto/anomalías , Recto/embriología , Reproducibilidad de los Resultados
12.
Environ Sci Pollut Res Int ; 22(2): 903-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25256586

RESUMEN

The objective of this work was to study the degradation and mineralization of ethylenethiourea (ETU) in water by ozonation at different pH values and in the presence of hydrogen peroxide. Degradation experiments were performed using an initial ETU concentration of 50 ppm for 180 min with a gas flux of 0.25 dm(3) min(-1) and an O3 production rate of 12.1 mg min(-1). Degradation of by-products was monitored by direct injection electrospray ionization mass spectrometry (ESI-MS), ETU concentration was determined by HPLC-UV, and its mineralization was detected by total organic carbon (TOC) analysis. Optimum degradation of ETU in water was observed at pH = 11, whereas at pH = 3, the degradation of ETU was slowest, indicating that the reaction occurred through different mechanisms. The additional effects of hydroxyl radicals formed at the highest pH can be used to explain the results obtained in this study. Peroxone experiments were carried out in the presence of 400 and 800 mg L(-1) H2O2; the degradation of ETU was faster at 400 mg L(-1) H2O2. This was attributed to the scavenging effect of the excess H2O2. ETU treatment by ozonation produced several by-products of degradation such as ethylene urea and 2-imidazoline.


Asunto(s)
Etilenotiourea/química , Ozono/química , Contaminantes Químicos del Agua/química , Etilenotiourea/análisis , Oxidación-Reducción , Plaguicidas/análisis , Plaguicidas/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua
13.
Environ Health Perspect ; 122(12): 1321-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25198283

RESUMEN

BACKGROUND: Mancozeb and its main metabolite ethylene thiourea (ETU) may alter thyroid function; thyroid hormones are essential for fetal brain development. In Costa Rica, mancozeb is aerially sprayed at large-scale banana plantations on a weekly basis. OBJECTIVES: Our goals were to evaluate urinary ETU concentrations in pregnant women living near large-scale banana plantations, compare their estimated daily intake (EDI) with established reference doses (RfDs), and identify factors that predict their urinary ETU concentrations. METHODS: We enrolled 451 pregnant women from Matina County, Costa Rica, which has large-scale banana production. We visited 445 women up to three times during pregnancy to obtain urine samples (n = 872) and information on factors that possibly influence exposure. We determined urinary ETU concentrations using liquid chromatography mass spectrometry. RESULTS: Pregnant women's median urinary ETU concentrations were more than five times higher than those reported for other general populations. Seventy-two percent of the women had EDIs above the RfD. Women who lived closest (1st quartile, < 48 m) to banana plantations on average had a 45% (95% CI: 23, 72%) higher urinary ETU compared with women who lived farthest away (4th quartile, ≥ 565 m). Compared with the other women, ETU was also higher in women who washed agricultural work clothes on the day before sampling (11%; 95% CI: 4.9, 17%), women who worked in agriculture during pregnancy (19%; 95% CI: 9.3, 29%), and immigrant women (6.2%; 95% CI: 1.0, 13%). CONCLUSIONS: The pregnant women's urinary ETU concentrations are of concern, and the principal source of exposure is likely to be aerial spraying of mancozeb. The factors predicting ETU provide insight into possibilities for exposure reduction.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Etilenotiourea/análisis , Fungicidas Industriales/efectos adversos , Maneb/efectos adversos , Exposición Materna , Zineb/efectos adversos , Adolescente , Adulto , Agricultura , Costa Rica , Exposición a Riesgos Ambientales , Femenino , Edad Gestacional , Humanos , Embarazo , Diagnóstico Prenatal
14.
J Environ Sci Health B ; 49(4): 263-70, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24502213

RESUMEN

In this study, photocatalytic (photo-Fenton and H2O2/UV) and dark Fenton processes were used to remove ethylenethiourea (ETU) from water. The experiments were conducted in a photo-reactor with an 80 W mercury vapor lamp. The mineralization of ETU was determined by total organic carbon analysis, and ETU degradation was qualitatively monitored by the reduction of UV absorbance at 232 nm. A higher mineralization efficiency was obtained by using the photo-peroxidation process (UV/H2O2). Approximately 77% of ETU was mineralized within 120 min of the reaction using [H2O2]0 = 400 mg L(-1). The photo-Fenton process mineralized 70% of the ETU with [H2O2]0 = 800 mg L(-1) and [Fe(2+)] = 400 mg L(-1), and there is evidence that hydrogen peroxide was the limiting reagent in the reaction because it was rapidly consumed. Moreover, increasing the concentration of H2O2 from 800 mg L(-1) to 1200 mg L(-1) did not enhance the degradation of ETU. Kinetics studies revealed that the pseudo-second-order model best fit the experimental conditions. The k values for the UV/H2O2 and photo-Fenton processes were determined to be 6.2 × 10(-4) mg L(-1) min(-1) and 7.7 × 10(-4) mg L(-1) min(-1), respectively. The mineralization of ETU in the absence of hydrogen peroxide has led to the conclusion that ETU transformation products are susceptible to photolysis by UV light. These are promising results for further research. The processes that were investigated can be used to remove pesticide metabolites from drinking water sources and wastewater in developing countries.


Asunto(s)
Etilenotiourea/química , Plaguicidas/química , Contaminantes Químicos del Agua/química , Cinética , Fotólisis , Rayos Ultravioleta , Purificación del Agua
15.
J Occup Environ Med ; 55(11): 1286-92, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24164757

RESUMEN

OBJECTIVE: To compare workplace characteristics, workplace behaviors, and the health beliefs of female farmworkers of childbearing age with actual biomarkers of exposure to organophosphate pesticides and to the fungicide mancozeb. METHODS: Hispanic and Haitian farmworkers between the ages of 18 and 40 years working in nursery or fernery operations were recruited to participate in a cross-sectional survey, examining demographics, work practices, work-related hygiene, and pesticide exposure beliefs. Single-void (spot) urine samples were analyzed for organophosphate and ethylenethiourea metabolites. RESULTS: Women in nurseries worried less frequently about the effects of pesticides on their health than those in fernery operations. In summary, organophosphate and ethylenethiourea levels in nursery workers were significantly higher than levels in fernery workers and the control group. CONCLUSIONS: Results showed that perceived pesticide exposure did not correspond to actual metabolite levels within differing agricultural subpopulations.


Asunto(s)
Agricultura , Conocimientos, Actitudes y Práctica en Salud , Insecticidas/orina , Exposición Profesional/análisis , Organofosfatos/orina , Adulto , Biomarcadores/orina , Estudios Transversales , Etilenotiourea/análisis , Femenino , Florida , Fungicidas Industriales/orina , Haití/etnología , Hispánicos o Latinos/psicología , Humanos , Higiene , Maneb/orina , Percepción , Lugar de Trabajo , Zineb/orina
16.
Acta Cir Bras ; 27(12): 897-904, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23207758

RESUMEN

PURPOSE: To evaluate hepatic morphological-histological abnormalities in newborns from female rats exposed to ethylenethiourea. METHODS: A randomized study was conducted on fifty-five newborn Wistar rats were studied: 34 in the experimental group, whose mothers had been exposed to 1% ethylenethiourea; and 21 in the control group, whose mothers had received 0.9% physiological solution. The solution was administered via gavage on the 11(th) day of gestation. Cesarean section was performed on the 20(th) day of gestation. The newborns' livers were examined and any morphological-histological abnormalities were registered. The presence of megakaryocytes was quantified in 50 microscope fields, as the total number of these cells per mm(2). RESULTS: The entire experimental group presented abnormalities of embryonic formation, with musculoskeletal anomalies, digestive system anomalies, hepatic congestion and friability, hydrops and delayed intrauterine growth. The histopathological analysis showed that morphological-histological hepatic destructuring had occurred in all entire experimental with removal of the hepatic trabeculae and severe hepatic megakaryocytosis. The mean megakaryocyte density ranged from 107.9 to 114.2 per mm(2), and it was eight times greater than in the control group, thus characterizing a situation of extramedullary hematopoiesis. CONCLUSION: The fetal exposure to ethylenethiourea caused hepatic damage characterized by severe extramedullary hematopoiesis.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Etilenotiourea/toxicidad , Plaguicidas/toxicidad , Efectos Tardíos de la Exposición Prenatal/patología , Animales , Animales Recién Nacidos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Femenino , Hematopoyesis Extramedular/efectos de los fármacos , Modelos Animales , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Distribución Aleatoria , Ratas , Ratas Wistar
17.
Acta cir. bras ; Acta cir. bras;27(12): 897-904, dez. 2012. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-657975

RESUMEN

PURPOSE: To evaluate hepatic morphological-histological abnormalities in newborns from female rats exposed to ethylenethiourea. METHODS: A randomized study was conducted on fifty-five newborn Wistar rats were studied: 34 in the experimental group, whose mothers had been exposed to 1% ethylenethiourea; and 21 in the control group, whose mothers had received 0.9% physiological solution. The solution was administered via gavage on the 11th day of gestation. Cesarean section was performed on the 20th day of gestation. The newborns' livers were examined and any morphological-histological abnormalities were registered. The presence of megakaryocytes was quantified in 50 microscope fields, as the total number of these cells per mm². RESULTS: The entire experimental group presented abnormalities of embryonic formation, with musculoskeletal anomalies, digestive system anomalies, hepatic congestion and friability, hydrops and delayed intrauterine growth. The histopathological analysis showed that morphological-histological hepatic destructuring had occurred in all entire experimental with removal of the hepatic trabeculae and severe hepatic megakaryocytosis. The mean megakaryocyte density ranged from 107.9 to 114.2 per mm², and it was eight times greater than in the control group, thus characterizing a situation of extramedullary hematopoiesis. CONCLUSION: The fetal exposure to ethylenethiourea caused hepatic damage characterized by severe extramedullary hematopoiesis.


OBJETIVO: Avaliar alterações hepáticas morfohistológicas em recém-nascidos de ratas prenhes expostas à etilenotioureia. MÉTODOS: Realizado ensaio randomizado em animais de experimentação, onde foram estudados 55 recém-nascidos de ratas Wistar, 34 do Grupo Experimento, expostas a etilenotioureia 1% e 21 do Grupo Controle, em que a rata prenhe recebeu solução fisiológica 0,9%, ambos por gavagem no 11º dia de gestação. Realizada no 20º dia de gestação cesariana, analisados os fígados dos recém-nascidos e registradas as alterações morfohistológicas. Realizou-se a quantificação dos megacariócitos em 50 campos microscópicos, avaliando a quantidade total destas células por mm². RESULTADOS: Todos os recém-nascidos do Grupo Experimento apresentaram alterações na formação embrionária, com anomalias musculoesqueléticas, anormalidades do sistema digestório, congestão e friabilidade hepática, hidropisia e crescimento intrauterino retardado. A análise histopatológica mostrou desestruturação hepática morfohistológica em todos os recém-nascidos expostos à etilenotioureia, com destrabeculação dos hepatócitos e intensa megacariocitose hepática, apresentando média da densidade de megacariócitos de 107,9 até 114,2 por mm² sendo cerca de oito vezes maior que no Grupo Controle, caracterizando hematopoese extramedular. CONCLUSÃO: A exposição fetal a etilenotioureia provocou danos hepáticos caracterizados pela intensa hematopoese extramedular.


Asunto(s)
Animales , Femenino , Embarazo , Ratas , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Etilenotiourea/toxicidad , Plaguicidas/toxicidad , Efectos Tardíos de la Exposición Prenatal/patología , Animales Recién Nacidos , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Hematopoyesis Extramedular/efectos de los fármacos , Modelos Animales , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Distribución Aleatoria , Ratas Wistar
18.
Acta Cir Bras ; 27(3): 244-50, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22460255

RESUMEN

PURPOSE: The pathophysiology of abnormalities associated with myenteric plexus lesions remains imperfectly understood. Such abnormalities have been correlated with subocclusive intestinal conditions in children with Hirschsprung's disease, cases of chronic constipation and, postoperatively, in cases of anorectal anomalies. This study evaluated abnormalities of the myenteric plexus in fetus from female rats that received ethylenethiourea. METHODS: Female rats were exposed to ethylenethiourea on the 11(th) day of pregnancy (experimental group) or to 0.9% physiological solution (control group). Abnormalities were only found in the experimental group. The digestive tract muscle layer was analyzed morphometrically and changes to the frequencies of nerve plexus cells and interstitial cells of Cajal were evaluated, using hematoxylin-eosin, S-100 protein, neuron-specific enolase and C-Kit, respectively. RESULTS: Muscle and skeletal abnormalities were observed in 100%, anorectal anomalies in 86%, absent tail in 71%, short tail in 29%, duodenal atresia in 5%, esophageal atresia in 5% and persistent omphalomesenteric duct in 5%. Histopathological analysis showed a thinner muscle layer associated with lower frequencies of ganglion cells and interstitial cells of Cajal, in all gastrointestinal tract. CONCLUSION: Severe nerve plexus abnormalities associated with muscle layer atrophy were observed throughout the gastrointestinal tract in newborn rats exposed to ethylenethiourea.


Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Anomalías del Sistema Digestivo/inducido químicamente , Etilenotiourea/toxicidad , Atrofia Muscular/inducido químicamente , Plexo Mientérico/anomalías , Embarazo/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Músculos Abdominales/inervación , Animales , Animales Recién Nacidos , Anomalías del Sistema Digestivo/clasificación , Anomalías del Sistema Digestivo/patología , Modelos Animales de Enfermedad , Femenino , Feto/efectos de los fármacos , Ganglios/citología , Células Intersticiales de Cajal/citología , Atrofia Muscular/patología , Efectos Tardíos de la Exposición Prenatal/patología , Distribución Aleatoria , Ratas , Ratas Wistar , Coloración y Etiquetado/métodos , Estadísticas no Paramétricas
19.
Acta cir. bras ; Acta cir. bras;27(3): 244-250, Mar. 2012. ilus, graf
Artículo en Inglés | LILACS | ID: lil-617964

RESUMEN

PURPOSE: The pathophysiology of abnormalities associated with myenteric plexus lesions remains imperfectly understood. Such abnormalities have been correlated with subocclusive intestinal conditions in children with Hirschsprung's disease, cases of chronic constipation and, postoperatively, in cases of anorectal anomalies. This study evaluated abnormalities of the myenteric plexus in fetus from female rats that received ethylenethiourea. METHODS: Female rats were exposed to ethylenethiourea on the 11th day of pregnancy (experimental group) or to 0.9 percent physiological solution (control group). Abnormalities were only found in the experimental group. The digestive tract muscle layer was analyzed morphometrically and changes to the frequencies of nerve plexus cells and interstitial cells of Cajal were evaluated, using hematoxylin-eosin, S-100 protein, neuron-specific enolase and C-Kit, respectively. RESULTS: Muscle and skeletal abnormalities were observed in 100 percent, anorectal anomalies in 86 percent, absent tail in 71 percent, short tail in 29 percent, duodenal atresia in 5 percent, esophageal atresia in 5 percent and persistent omphalomesenteric duct in 5 percent. Histopathological analysis showed a thinner muscle layer associated with lower frequencies of ganglion cells and interstitial cells of Cajal, in all gastrointestinal tract. CONCLUSION: Severe nerve plexus abnormalities associated with muscle layer atrophy were observed throughout the gastrointestinal tract in newborn rats exposed to ethylenethiourea.


OBJETIVO: As anomalias associadas a lesões dos plexos mioentéricos permanecem sem plena compreensão da sua fisiopatologia. Alterações nos plexos nervosos têm sido correlacionadas com quadros suboclusivos intestinais em crianças portadoras de doença de Hirschsprung, em constipação crônica e no pós-operatório de anomalias anorretais. Este estudo avaliou as anomalias do plexo mioentérico em fetos de ratos fêmea que ingeriram etilenotioureia (ETU). MÉTODOS: Ratos fêmea foram expostos no 11º dia de gestação a ETU 1 por cento no Grupo Experimento e a solução fisiológica 0,9 por cento no Grupo Controle. Foram observadas anomalias apenas no Grupo experimento, sendo realizada morfometria da camada muscular e avaliadas alterações da frequência celular nos gânglios do plexo mioentérico e nas células intersticiais de Cajal (CIC) utilizando hematoxilina-eosina, P S-100, Enolase Neurônio Específica e C-KIT. RESULTADOS: Foram observadas anomalias musculoesqueléticas (100 por cento), anorretais (86 por cento), ausência de cauda (71 por cento), cauda curta (29 por cento), atresia duodenal (5 por cento), atresia esofágica (5 por cento) e conduto onfalomesentérico persistente (5 por cento). A análise histopatológica mostrou adelgaçamento da camada muscular associada às alterações da frequência das células ganglionares e das CIC em todos os segmentos do trato gastrointestinal. CONCLUSÃO: Foram observadas alterações graves nos plexos nervosos associadas ao adelgaçamento da camada muscular de todo o trato gastrointestinal nos fetos expostos a ETU.


Asunto(s)
Animales , Femenino , Ratas , Anomalías Inducidas por Medicamentos/patología , Anomalías del Sistema Digestivo/inducido químicamente , Etilenotiourea/toxicidad , Atrofia Muscular/inducido químicamente , Plexo Mientérico/anomalías , Embarazo/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Animales Recién Nacidos , Músculos Abdominales/inervación , Modelos Animales de Enfermedad , Anomalías del Sistema Digestivo/clasificación , Anomalías del Sistema Digestivo/patología , Feto/efectos de los fármacos , Ganglios/citología , Células Intersticiales de Cajal/citología , Atrofia Muscular/patología , Efectos Tardíos de la Exposición Prenatal/patología , Distribución Aleatoria , Ratas Wistar , Estadísticas no Paramétricas , Coloración y Etiquetado/métodos
20.
Acta cir. bras. ; 27(3): 244-250, 2012. ilus, graf
Artículo en Inglés | VETINDEX | ID: vti-3982

RESUMEN

PURPOSE: The pathophysiology of abnormalities associated with myenteric plexus lesions remains imperfectly understood. Such abnormalities have been correlated with subocclusive intestinal conditions in children with Hirschsprung's disease, cases of chronic constipation and, postoperatively, in cases of anorectal anomalies. This study evaluated abnormalities of the myenteric plexus in fetus from female rats that received ethylenethiourea. METHODS: Female rats were exposed to ethylenethiourea on the 11th day of pregnancy (experimental group) or to 0.9 percent physiological solution (control group). Abnormalities were only found in the experimental group. The digestive tract muscle layer was analyzed morphometrically and changes to the frequencies of nerve plexus cells and interstitial cells of Cajal were evaluated, using hematoxylin-eosin, S-100 protein, neuron-specific enolase and C-Kit, respectively. RESULTS: Muscle and skeletal abnormalities were observed in 100 percent, anorectal anomalies in 86 percent, absent tail in 71 percent, short tail in 29 percent, duodenal atresia in 5 percent, esophageal atresia in 5 percent and persistent omphalomesenteric duct in 5 percent. Histopathological analysis showed a thinner muscle layer associated with lower frequencies of ganglion cells and interstitial cells of Cajal, in all gastrointestinal tract. CONCLUSION: Severe nerve plexus abnormalities associated with muscle layer atrophy were observed throughout the gastrointestinal tract in newborn rats exposed to ethylenethiourea.(AU)


OBJETIVO: As anomalias associadas a lesões dos plexos mioentéricos permanecem sem plena compreensão da sua fisiopatologia. Alterações nos plexos nervosos têm sido correlacionadas com quadros suboclusivos intestinais em crianças portadoras de doença de Hirschsprung, em constipação crônica e no pós-operatório de anomalias anorretais. Este estudo avaliou as anomalias do plexo mioentérico em fetos de ratos fêmea que ingeriram etilenotioureia (ETU). MÉTODOS: Ratos fêmea foram expostos no 11º dia de gestação a ETU 1 por cento no Grupo Experimento e a solução fisiológica 0,9 por cento no Grupo Controle. Foram observadas anomalias apenas no Grupo experimento, sendo realizada morfometria da camada muscular e avaliadas alterações da frequência celular nos gânglios do plexo mioentérico e nas células intersticiais de Cajal (CIC) utilizando hematoxilina-eosina, P S-100, Enolase Neurônio Específica e C-KIT. RESULTADOS: Foram observadas anomalias musculoesqueléticas (100 por cento), anorretais (86 por cento), ausência de cauda (71 por cento), cauda curta (29 por cento), atresia duodenal (5 por cento), atresia esofágica (5 por cento) e conduto onfalomesentérico persistente (5 por cento). A análise histopatológica mostrou adelgaçamento da camada muscular associada às alterações da frequência das células ganglionares e das CIC em todos os segmentos do trato gastrointestinal. CONCLUSÃO: Foram observadas alterações graves nos plexos nervosos associadas ao adelgaçamento da camada muscular de todo o trato gastrointestinal nos fetos expostos a ETU.(AU)


Asunto(s)
Animales , Feto/anomalías , Ratas/clasificación , Tracto Gastrointestinal/anatomía & histología , Anomalías del Sistema Digestivo/veterinaria , Etilenotiourea/análisis
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