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Estrous Cycle and Early Pregnancy of White Mice Exposed to Methomyl
2019
Toledo, J. M. | Gamalo, L. E. | Maligalig, M. D. | Suetos, K. J. | Galapon, M.
Methomyl is an oxime carbamate pesticide that is widely used in the Philippines. This insecticide is known to be an endocrine disrupting chemical and a potent genotoxic in mammalian cells. However, limited studies were conducted specifically on its direct effects on estrous cycle and its teratogenic effect. This study aimed to (a) assess the effect of methomyl on the body weight and on the estrous cycle of mice, and; (b) examine the teratogenic effect of methomyl on the progeny of the female albino mice. Five week-old experimental mice in three treatment setups were used in the study for both independent experiments. The treatment schedule for pregnant mice was administered during organogenesis (day 6 to 15 of gestation). Results showed that the average gained weight of the mice of both high dose (HD) and low dose (LD) groups were lower as compared to the average gained weight of the control group but did not show any statistical significant differences (p=0.562). For the experiment 1, methomyl significantly (p=0.013) affect the estrous cycle of the mouse especially in LD group. For experiment 2, results revealed that there was a significant difference among the treatment set-ups (p=0.0001) in terms of fetal morphometric measurement. Furthermore, abnormality and high number of resorption was also observed in both LD and HD treatment groups. Therefore, methomyl significantly affect the body weight, estrous cycle and fetal morphometry. This further confirm that methomyl is an endocrine disrupting and genotoxic chemical that affects the estrous cycle and causes teratogenic effect.
Mostrar más [+] Menos [-]Side-effects of pesticides on ground-dwelling predatory arthropods in arable ecosystems.
1989
Everts J.W. | Aukema B. | Hengeveld R. | Koeman J.H.
Trends in organochlorine and mercury levels in gannet eggs.
1990
Newton I. | Haas M.B. | Freestone P.
Organochlorine and heavy metal contamination in non-viable eggs and its relation to breeding success in a Spanish population of lesser kestrels (Falco naumanni).
1993
Negro J.J. | Donazar J.A. | Hiraldo F. | Hernandez L.M. | Fernandez M.A.
Organochlorine pesticide residues in marine sediment and biota from the Northern Florida reef tract.
1995
Glynn P.W. | Rumbold D.G. | Snedaker S.C.
Persistent organochlorine residues in harbour porpoise (Phocoena phocoena) from the Black Sea.
1997
Tanabe S. | Madhusree B. | Ozturk A.A. | Tatsukawa R. | Miyazaki N. | Ozdamar E. | Aral O. | Samsun O. | Ozturk B.
Evaluation of fate and exposure models - Pesticides and groundwater quality protection - Calibrating a simple model for ranking the contamination potential.
1994
Bacci E. | Franchi A. | Bensi L. | Gaggi C.
A simple approach for ranking the leaching of pesticides from surface soil presented and tentatively calibrated with field data from an agricultural a The approach is based on the calculation of a leaching index indicating the proportion of active ingredient, with respect to the quantity applied, leac from a soil model in a given time interval (one year). In the selected area wells tapping an unconfined aquifer were sampled for groundwater pesticide residue analysis, in order to explore the index region between leachers and nonleachers.
Mostrar más [+] Menos [-]Physical limitation of pesticides (chlordecone) decontamination in volcanic soils: Fractal approach and numerical simulation
2020
Woignier, Thierry | Rangon, Luc | Clostre, Florence | Mottes, Charles | Cattan, Philippe | Primera, Philippe | Jannoyer, Magalie
In the French West Indies, the chlordecone (organochloride pesticide) pollution is now diffuse becoming new contamination source for crops and environment (water, trophic chain). Decontamination by bioremediation and chemical degradation are still under development but the physical limitations of these approaches are generally not taken into account. These physical limitations are related to the poor physical accessibility to the pesticides in soils because of the peculiar structural properties of the contaminated clays (pore volume, transport properties, permeability, and diffusion). Some volcanic soils (andosols), which represent the half of the contaminated soils in Martinique, contain nanoclay (allophane) with a unique structure and porous properties. Andosols are characterized by pore size distribution in the mesoporous range, a high specific surface area, a large pore volume, and a fractal structure. Our hypothesis is that the clay microstructure characteristics are crucial physico-chemical factors strongly limiting the remediation of the pesticide. Our results show that allophane microstructure (small pore size, hierarchical microstructure, and tortuosity) favors accumulation of chlordecone, in andosols. Moreover, the clay microporosity limits the accessibility of microorganisms and chemical species able to decontaminate because of poor transport properties (permeability and diffusion). We model the transport properties by two approaches: (1) we use a numerical model to simulate the structure of allophane aggregates. The algorithm is based on a cluster–cluster aggregation model. From the simulated data, we derived the pore volume, specific surface area, tortuosity, permeability, and diffusion. We show that transport properties strongly decrease because of the presence of allophane. (2) The fractal approach. We characterize the fractal features (size of the fractal aggregate, fractal dimension, tortuosity inside allophane aggregates) and we calculate that transport properties decrease of several order ranges inside the clay aggregates. These poor transport properties are important parameters to explain the poor accessibility to pollutants in volcanic soils and should be taken into account by future decontamination process. We conclude that for andosols, this inaccessibility could render inefficient some of the methods proposed in the literature.
Mostrar más [+] Menos [-]Do constructed wetlands in grass strips reduce water contamination from drained fields?
2015
Vallée, Romain | Dousset, Sylvie | Schott, François-Xavier | Pallez, Christelle | Ortar, Agnès | Cherrier, Richard | Munoz, Jean-François | Benoît, Marc | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement (INEE) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Chambre Régionale d'Agriculture de Lorraine (CRA Lorraine [Laxou]) ; Chambre Régionale d'Agriculture Grand Est | Laboratoire d'hydrologie de Nancy (LHN) ; Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES) | Agro-Systèmes Territoires Ressources Mirecourt (ASTER Mirecourt) ; Institut National de la Recherche Agronomique (INRA) | Agence de l'Eau Rhin-Meuse [09A54015]; Zone Atelier Moselle
International audience | This study evaluates the efficiency of two small constructed wetlands installed in the regulatory grass strips between a drained plot and a river. The observed nitrate removal efficiencies were independent of the season or type of constructed wetland and ranged from 5.4 to 10.9% of the inlet amounts. The pesticide mass budgets ranged from −618.5 to 100%, depending on the molecule. The negative efficiencies were attributed to runoff and remobilization. In contrast, the highest efficiencies were associated with pesticides with high Koc and low DT50 (half-life) values, suggesting sorption and degradation. However, the effectiveness of these wetlands is limited for pesticides with low Koc or high DT50 values; thus, the use of these molecules must be reduced. Increasing the number of these small, inexpensive and low-maintenance wetlands in the agricultural landscape would reduce the level of water pollution whilst preserving the extent of cultivated land, but their long-term effectiveness should be evaluated.
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