Determinación de etilentiourea en acelgas tratadas con Zineb: Efecto del calor húmedo por ebullición / Determination of ethylenethiourea in chard treated with Zineb: Effect of wet heat by boiling

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.

Effects of polymeric zinc propylen-bis-dithiocarbamate (propineb) on nasal mucosa in rats / Efectos de los polímeros del zinc propileno-bis-ditiocarbamato (propineb) en la mucosa nasal de ratas

The objective of this study was to evaluate the histopathologic and immunohistochemical effects of propineb on rat nasal mucosa. Twenty adult Sprague-Dawley rats weighing 180­220 g, were used as experimental animals. The rats were divided into propineb and control groups. The control group received distilled water with spray at the same time period. The experiment was terminated after three weeks. In each case, sections of the nosewere taken. In experimental group, microscopic examination of nasal respiratory mucosa revealed that degenerative changes in epithelium were observed in sections of propineb-treated group. There were also leukocyte infiltration and vascular dilatation detected in the connective tissue.We detected CD34-immunoreactive mononuclear cells and endothel cells in the lamina propria of propineb group. In propineb group compared to the control group, the respiratory epithelium, goblet and basal cell nuclei were stained positive for PCNA. Propineb inhalation may be irritating to the nasal mucosa.

El objetivo de este estudio fue evaluar los efecto histopatológicos e inmunohistoquímicos del Propineb en la mucosa nasal de 20 ratas Sprague-Dawley adultas con un peso de 180-220 g, las que fueron utilizadas como animales de experimentación. Las ratas se dividieron en grupos Propineb y Control. El grupo control recibió agua destilada en aerosol nasal en el mismo período de tiempo que el grupo Propineb. El experimento duró tres semanas. Posteriormente, en cada caso se tomaron muestras de la mucosa nasal. En el grupo experimental, tratado con Propineb, el examen microscópico de la mucosa respiratoria nasal reveló cambios degenerativos en el epitelio. Se detectó también infiltración de leucocitos y dilatación vascular en el tejido conectivo, junto con células mononucleares CD34 inmunorreactiva y células endoteliales en la lámina propia. En el grupo Propineb, en comparación con el grupo control, los núcleos de la porción respiratoria, las células caliciformes y basales resultaron positivas a la tinción del antígeno nuclear de proliferación celular (PCNA). La inhalación de Propineb puede ser un irritante para la mucosa nasal.

The effects of polymeric zinc propylen-bis-dithiocarbamate (Propineb) on tooth development in rats / Efectos del propileno-bis-ditiocarbamato de zinc polimérico (Propineb) sobre el desarrollo de los dientes en ratas

Dithiocarbamate propinebs are organometal fungicides that are widely used for the control of diseases in plants. In this study, pregnant female rats received 400 ppm propineb concentrations in 5 ml distilled water for 16 days of gestation, and then infant rats were obtained by cesarean section. In the histological analysis on the frontal sections, the use of propineb was found effective on odontoblast cell hyperplasia, cell infiltration in the dental papilla, and degeneration in the mesenchymal cells of the outer enamel. The expression of MMP-2 (Matrix Metalloproteinase-2) and VEGF (Endothelial cell growth factor) in the connective tissue was evaluated by immunohistochemistry. The drinking water given to the mothers in propineb tooth bud, enamel and dentin, resulted in morphological changes suggestive of a delay in formation, which cross the placental barrier and possibly affect the tooth development.

Los ditiocarbamatos (Propineb) son fungicidas organometálicos que son ampliamente utilizados para el control de enfermedades en las plantas. En este estudio, ratas hembras preñadas recibieron concentraciones de 4000 ppm de propineb en 5 ml de agua destilada durante 16 días de su gestación. Luego, las crías de las ratas fueron obtenidas mediante cesárea para su estudio estudio histológico. En el análisis histológico de las secciones frontales, el uso de propineb fue positivo para la hiperplasia de las células odontoblástica, infiltración de células en la papila dental, y la degeneración en las células mesenquimales del epitelio externo del esmalte. La expresión de MMP-2 (metaloproteinasa de la matriz 2) y VEGF (factor de crecimiento de células endoteliales) en el tejido conectivo se evaluó por inmunohistoquímica. El agua potable con propineb dada a las madres actuó sobre el brote dentario, esmalte y dentina; se tradujo en cambios morfológicos indicativos de un retraso en la formación. Por tanto, el propineb atraviesa la barrera placentaria y posiblemente afecten el desarrollo de los dientes.

Protective effect of olive oil against Teratogenecity induced by Mancozeb in albino rats

Aim: this study aimed to investigate the protective effect of extra-virgin olive oil [EVOO] against teratogenicity of the fungicide mancozeb

Methods: after pregnancy confirmation, 32 pregnant rats were divided into 4-groups [n=8]. The 1[st] group orally administered tap water [-ve control], the 2[nd] group [+ve control] was administered EVOO [0.5ml/dam] from the1[st] to 20[th] day of pregnancy. The 3rd and the 4[th] groups were administered 200 mg/kg mancozeb during the period of organogenesis, from the 6[th] to 15[th] day of pregnancy. The 4[th] group received the mentioned dose of EVOO prior to the pesticide administration. Cesarean section was performed on day 20 of pregnancy and the maternal and fetal parameters were recorded

Results: mancozeb induced maternal toxicity manifested as lower body weight gain of dams, increased number of late resorption sites/litter in comparison with the control group and mancozeb group pretreated with EVOO. Mancozeb evoked a decrease in fetal body weight, altered sex ratio [M/F] as well as increased incidence of fetal external, visceral and skeletal abnormalities. Treatment with virgin oil reduced the congenital malformations

Conclusively, the present study elucidates the protective role of EVOO as a result of antioxidant activity which scavenges the reactive oxygen species which induced cytotoxicity and increased prenatal mortalities.

Ultrastructural effects of the propineb on brain of fetuses during rat pregnancy / Efectos ultraestructurales de propineb en el cerebro de fetos durante el embarazo de ratón

Propineb is a fungicide with a propylene-bis-dithiocarbamate structure. Pregnant Wistar rats were exposed to 400 ppm propineb concentrations in 5 ml distilled water, 5 days per week until the end of pregnancy. The rats were treated with propineb for 16 days and the brains of litter rats were sacrificed at first day of birth after which their brains were collected. Ultrastructural examination of the brains of the fetuses and propineb-treated pregnant females revealed a variety of histopathological effects. We suggest that mitochondrial damage may be an effective factor for neuron necrosis. These results supported the proposal that the exposure to fungicides such as propineb and to other naturally occurring compounds which inhibit mitochondrial function, may contribute to Parkinson's disease development.

El Propineb es un fungicida con una estructura de propileno-bis-ditiocarbamato. Ratas Wistar preñadas fueron expuestas a concentraciones de depropineb (400 ppm) en 5 ml de agua destilada, 5 días por semana hasta el final de la preñez. Las ratas fueron tratadas por 16 días y las crías fueron sacrificados el primer día de nacimiento para recolectar sus cerebros. El examen ultraestructural de los cerebros de los fetos y las hembras preñadas tratadas con propineb reveló una variedad de efectos histopatológicos. Sugerimos que el daño mitocondrial puede ser un factor eficaz para la necrosis neuronal. Estos resultados apoyaron la propuesta de que la exposición a los fungicidas tales como propineb y de otros compuestos de origen natural que inhiben la función mitocondrial, puede contribuir al desarrollo de la enfermedad de Parkinson.

Identification of the Fungal Pathogen that Causes Strawberry Anthracnose in Bangladesh and Evaluation of In Vitro Fungicide Activity

This study was conducted to identify the Colletotrichum species causing anthracnose disease of strawberry in Balgladesh and to evaluate in vitro activity of commercial fungicides it. Based on morphological and cultural characteristics, all 22 isolates were identified as Colletotrichum gloeosporioides. They developed white or glittery colonies with grey to dark grey reverse colony colors and they produced cylindrical conidia. The efficacy of five commercial fungicides, Bavistin DF, Dithane M-45, Sulcox 50 WP, Corzim 50 WP and Rovral 50 WP, were tested against the fungus. Bavistin inhibited radial growth completely and was followed in efficacy by Dithane M-45. In Bavistin DF treated media, the fungus did not produce conidia. The percent inhibition of radial growth of the fungus was increased with the increasing concentrations of fungicide.

Inhibitory Effect of Algal Extracts on Mycelial Growth of the Tomato-Wilt Pathogen, Fusarium oxysporum f. sp. lycopersici

The present study was undertaken to explore the inhibitory effect of cyanobacterial extracts of Nostoc commune FA-103 against the tomato-wilt pathogen, Fusarium oxysporum f. sp. lycopersici. In an optimal medium, cell growth, antifungal activity, and antifungal compound production could be increased 2.7-fold, 4.1-fold, and 13.4-fold, respectively. A crude algal extract had a similar effect as mancozeb at the recommended dose, both in laboratory and pot tests. In vitro and in vivo fungal growth, spore sporulation and fungal infection of wilt pathogen in tomato seeds were significantly inhibited by cyanobacterial extracts. Nostoc commune FA-103 extracts have potential for the suppression of Fusarium oxysporum f. sp. lycopersici.

Testing of seed-borne fungi of Glycyrrihiza seed and disinfection effect of several fungicides on seed-borne fungi / 中国中药杂志

<p><b>OBJECTIVE</b>To study the dominant seed-borne fungi of Glycyrrihiza seeds which were from different producing area and compare the disinfection effect of several fungicides on seed-borne fungi of Glycyrrihiza seed.</p><p><b>METHOD</b>Petri-dish testing was used to determine the external and internal seed-borne fungi and the disinfection effect of fungicides.</p><p><b>RESULT AND CONCLUSION</b>The result showed that the amount of spore on the surface of one Glycyrrihiza seed varied from 0.3% to 37.0% among samples. Penicillium spp. and Aspergillus spp. were the two major dominant fungi and there was few differences in the type of the fungi among producing areas but differences in the isolation frequency of the furgi; Penicillium spp. , Rhizopus spp. , Aspergillus spp. and Alternaria spp. were the internally dominant seed-borne fungi, including seed capsule and the internal tissue of seed and their fungi-carrying percentage was 8.0%-48.3% and 3.5%-42.0% respectively. There were differences in fungi percentage and dominant seed borne fungi among different producing areas. The disinfection effect of both mancozeb and thriam was up to 89.0%, so it is suggested to use them to disinfect Glycyrrihiza seed.</p>

[Investigation and measurement of pesticidal residues; benomil and mancazeb in cucumber produced in Mazandaran]

Considering the importance and usefulness of fruits in people's daily diet as they play an important role in determining public health and also considering the significance of pesticide residues in foods and fruits, measurement of which has been repeatedly reiterated by WHO and FAO, this research was done. Irregular use of pesticides by farmers knowingly or unknowingly without observing its caress period has led to the contact of these pesticides with humans through foods and fruits and in the long run, they will surely cause chronic complications. In this study, after collecting cucumbers form 76 sample regions, we rinsed them carefully, sliced them thinly and mashed them up. Then, we extracted them three times with n butyl acetate. Later, we evaporated the solvent. At the end, we measured the residue by chromatographic gas [GC] and detector [ECD]. The results obtained were analyzed with the help of two-way ANOVA. It indicated that there is a correlation between the investigated regions and the residual amount [P>0.05]. Calculation of the mean ratings showed that the levels of these two pesticides are higher than the acceptable level in most of the regions. [0.01]

Persistence and degradation of metalaxyl, mancozeb fungicides and its metabolite ethylenethiourea in soils.

The degradation pattern of metalaxyl, mancozeb and its metabolite ethylenethiourea (ETU) residues indicated a close correspondence to first order exponential degradation kinetics in soils. Degradation of fungicides in soils was predominantly biological as well as chemical in nature. Slower degradation ofmetalaxyl was noticed in the soils and their half-life values were higher than mancozeb and ETU as evident by wide range of half-life values from 41.24 to 165.11 days. In case of metalaxyl, Hiriyur soil was found to be superior in degrading the metalaxyl. Lower persistence of mancozeb and ETU was observed in soils resulting in rapid rate of degradation at smaller half-life values as compared to metalaxyl indicating the faster degradation of mancozeb and ETU. In mancozeb applied soils, the ETU formation was increased up to 30 days of incubation and thereafter it declined. Amongsoils, degradation of either mancozeb or ETU is not influenced by soil types. However, mancozeb persistence was higher in Hiriyur soils than Chettalli and Bangalore soils.

Assessment of toxicological effects of mancozeb in male rats after chronic exposure.

Mancozeb, an ethylenebisdithiocarbamate fungicide was administered orally to male rats at doses 0, 500, 1000 and 1500 mg/kg/day for 90, 180 and 360 days produced dose dependent signs of poisoning, loss in body weight gain and mortality. However the signs of toxicity and mortality were more pronounced initially at 0-90 days as compared to 90-360 days of treatment period. A significant increase in the relative weight of liver and slight decrease in the kidney weight were observed in animals exposed to mancozeb (1000 and 1500 mg/kg/day) for 180 and 360 days associated with pathomorphological changes in liver, brain and kidney. Mancozeb has produced significant enzymatic changes in the activities of aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and acetylcholinesterase (AChE) throughout the period of study in a dose dependent manner. The alterations in the activity of enzymes associated with pathomorphological changes suggest that the chronic exposure of mancozeb produced significant toxicological effects in rats.

Fungitoxic action of dithanes in presence of surfactant micelles.

A rationale of arriving at the concentration of surfactant additives in the pesticidal formulations has been discovered. Fungitoxic activity of each of the two dithanes, Dithane M-45 (maneb) and Dithane Z-78 (zineb) has been estimated in the presence of various concentrations of three surfactants namely sodium lauryl sulphate, cetyl pyridinium chloride and Tween 80. Data reveal that the concentration of the surfactant additives in the pesticidal formulations should be at least equal to its critical micelle concentration (CMC) for enhanced biological activity. This rationale for the concentration of surfactant additives in the pesticidal formulation has so far not been clearly brought out in the literature. Since biological activity of the pesticides is enhanced in the presence of surfactant additives the present study is relevant to the reduction of environmental pollution due to pesticide residues.

Influence of mancozeb on mitogenically responsive lipids in rat cerebrum and liver.

Mancozeb, a commonly used fungicide, has been shown to induce tumours in mouse skin and maneb, unit constituent of mancozeb, is reported to induce tumours in rats. The mechanism by which mancozeb induced tumorigenicity is not known. Since the levels of inositol phospholipids and phosphatidic acid have roles in the regulation of cell proliferation, the effects of mancozeb on the levels of these lipids were studied in rats. Daily oral administration of commercial grade mancozeb at a concentration of 50 mg/kg body wt for 30 days (5 days a week) caused no significant change in the levels of inositol phospholipids and phosphatidic acid (PA) in both cerebrum and liver, while at high concentration (250 mg/kg body wt) under the same treatment schedule mancozeb increased the levels of these lipids. In cerebrum, the levels of phosphatidylinositol (PI) and PA were increased by 36 and 43% respectively without affecting the levels of polyphosphoinositides, whereas in liver the levels of not only PI (50%) and PA (49%) but also those of polyphosphoinositides were increased. These results show that mancozeb influences the levels of PA and inositol phospholipids, involved in phospholipase C-pathway of signalling.