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English :
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Study on the effect of some chemical compounds on some organisms in aquatic media
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Arabic :
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دراسه تأثير بعض المركبات الكيميائية علي بعض الكائنات في البيئة المائية
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| Abstract |
Agrochemical residues are recognized as serious pollutants to aquatic environment, with deleterious effect on the associated organisms. Different research programs focused the remarkable hazard of pesticide residues on human health. As we known fish present one of the important source protein in Egypt. So, its contamination may create a public health menace. So proper disposal and detoxication of these pollutants from the environment has become very important.
So, this study was directed to focus the hazard of some insecticides (deltamethrin, dimethoate and lannate) and their mixture with the foliar fertilizer stimufol, on some aquatic organisms [Insect (Culex pipiens L.) and some fish (Gambusia affinis, Tilapia nilotica and Cyprinus carpio)].
Also, this study was investigated to employ a simple chromatographic and biochemical analysis methods for detecting the pesticides residues in water and fish to protect human health from their hazards.
The results could be summarized in the following points:
1. Determination of the toxicity of the tested compounds against some aquatic organisms.
a. Against mosquito larvae Culex pipiens L. The obtained results indicated that deltamethrin was the most potent compound tested against the 4th instar larvae with LCso of 1.1 x 10-4 ppm followed by lannate and dimethoate with LC50 of 0.897 and 4.5 ppm, respectively, while stimufol showed not toxic to the concentration of 150 ppm.
b. Against fish:
The results revealed that deltamethrin was the most potent compound tested against Gambusia affinis, Tilapia nilotica and Cyprinus carpio fish with LCso of 0.066, 0.008 and 0.133 ppm, respectively. Lannate and dimethoate showed less toxic than deltamethrin. Their LC50’s were 1.1, 0.56 and 0.552 ppm for lannate and 43.40, 33.67 and 84.85 ppm for dimethoate, respectively, while, stimufol showed not toxic against all kinds of fish to the concentration of 200 ppm.
2. The efficacy of the previous insecticides against all kind of tested fish in the presence of water plant (Ceratophylum demersum) and some phytoplankton using the lowest LC50’s of 0.008, 0.552, 33.67 ppm for deltamethrin, lannate and dimethoate respectively were determined. The results revealed a different changes in the toxic effect of the compounds against fish after 24 hours of treatment.
3. The effect of the tested compounds on the propagation of phytoplankton using the concentration of 0.008, 0.552 and 33.67 ppm for deltamethrin, lannate and dimethoate, respectively were studied. The obtained results indicated that, there is no significant effect on its propagation 24 hours after treatment.
4. The interaction effects of the tested insecticides at the LCZS concentration against mosquito larvae and at the 1/2 LC50 concentration against fish with the non toxic concentration (1 ppm) stimufol were studied. The obtained results after 24 hours of treatment revealed that:
a. With Culex pipiens, a synergistic effect was found in the case of deltamethrin and dimethoate, while only an additive effect was found with lannate.
b. With Gambusia affinis, a synergistic effect was found with lannate and dimethoate and an additive effect were showed with deltamethrin.
c. With Tilapia nilotica and Cyprinus carpio fish, the same effect was obtained with both kind of fish. Dimethoate showed a synergistic effect and an additive effect with deltamethrin and an antagonistic effect with lannate.
5. Thin-layer chromatographic analysis (TLC) was used to separate the tested compound from water, water-plant and fish extracts using different solvent systems.
a. For the separation of the insecticides tested and/or their mixtures with stimufol form water, solvent systems were used:
Benzene: Methylene chloride: Acetone (4: 1: 1) [A]
Acetone: Ethyl acetate: Petroleum ether (0.5: 45: 2) [B]
Methylene chloride: Petroleum ether: Acetone (3: 1: 1) [C]
No interference was found in all cases.
b. For the separation of the insecticides from water-plant extract (Ceratophyllum demersum), two solvent systems were used: Methylene chloride: Petroleum ether: Acetone (3: 1: 1) was used with deltamethrin and lannate, while the solvent system, acetone: ethylacetate: Petroleum ether (0.5: 4: 2) was used with dimethoate without any interference with plant extracts.
c. For the separation of the insecticides tested from fish (alive and dead), two solvent systems were used:
Acetone: ethylacetate: petroleum ether (0.5: 4: 2), and Methylene chloride: Petroleum ether: Acetone (3: 1: 1). The data revealed that no interference between insecticides and fish extracts.
6. Detection limits of deltamethrin, dimethoate, lannate and stimufol on developed TLC chromatoplates were determined using iodine vapor. Results revealed that this technique was found to be sensitive for detecting 4 jig for lannate, dimethoate and stimufol and 40 pg for deltamethrin.
7. The emulsion stability test of the previous compounds showed that all of these compounds and/or the mixtures with stimfol were stable in clean water up to 24 hours, while these preparation were not stable in the presence of fish in the same time. Also TLC chromatographic analysis showed that these emulsion were not stable at intervals with time, some degraded compounds were found 7 days after emulsions preparation.
8. Qualitative determination of insecticide residues in fish extracts were made using TLC technique. Results showed the presence of some degraded compounds in dead and alive fish after 24 hours of treatments, compared with that control extract.
9. Quantitative determination of total protein content in treated and untreated fish, revealed a decrease in protein level in treated fish. This decrease in total protein was less in alive fish than in dead fish.
10. The activity of acetyl cholinesterase (AchE) was determined in treated fish (alive and dead). The obtained data showed that dimethoate was the most potent compound in all cases than lannate or deltamethrin.
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| Publication year |
1994
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| Availability location |
معهد بحوث وقاية النباتات - ش نادى الصيد - الدقى - الجيزة
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| Availability number |
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| Organization Name |
Plant Protection Research Institute (PPRI)
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| Country |
Egypt
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| Publisher |
Name:
كليه الزراعه-جامعه طنطا
Place:
طنطا-مصر
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| Author(s) from ARC |
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| Agris Categories |
Protection of plants - General aspects
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AGROVOC
TERMS |
Aquatic organisms.
Culex pipiens.
Cyprinus carpio.
Dimethoate.
Fertilizer application.
Foliar application.
Gambusia affinis.
Oreochromis niloticus.
Pesticides.
Pollutants.
Residues.
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| Publication Type |
Master Thesis
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