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41.
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Abstract

Potato tubers were applied with radiolabelled lindane (U‐14C γ‐ 1,2,3,4,5,6 hexachlorocyclohexane) at three dose levels 30, 150, and 300 ppm and stored for 30, 60 and 90 days at room temperature. The data revealed that lindane penetrated into the pulp tissues through the epidermal layer. The amounts recovered in the peel were found to increase with a greater storage period up to 60 days followed by a drop at 90 days. On the other hand, there was a slight increase in radioactivity in the pulp tissue from 30 to 60 days followed by significant increase after 90 days. The incorporation of the compound in the tubers was dose independent. Methanol extraction showed binding of about 8.1% and 5.8% ofthe applied dose in peel and pulp tissues, respectively. The insecticide was found to be bioavailable when rats health hazard. It is therefore, desirable to demonstrate that the quantity of the terminal residues may be safe for the consumer. In the present investigation an attempt was made to determine the fate and bioavailability of lindane when applied to stored potato tubers.  相似文献   
43.
Mussels (Brachidontes Sp.) collected in April 2000 from the Red Sea coastal of Egypt in order to determine the contamination by hydrocarbons. The study included 11 sampling stations covering about 450 Km of the Egyptian Red Sea coast for the first time. Total concentrations of 20 aliphatics (average 0.105 ng g(-1) of wet weight) and sixteen polycyclic aromatic hydrocarbons (PAHs) (average 5452 ng g(-1) of wet weight) were generally lower in comparison with those reported for some of the published surveillance and monitoring studies of coastal areas from various regions. These results suggest that the coastal area in the Red Sea of Egypt might be considered as a relatively unpolluted.  相似文献   
44.
Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants of concern because of their ubiquitous presence in surface and ground water; analytical methods that can be used for rapid comprehensive exposure assessment and fingerprinting of PFAS are needed. Following the fires at the Intercontinental Terminals Company (ITC) in Deer Park, TX in 2019, large quantities of PFAS-containing firefighting foams were deployed. The release of these substances into the Houston Ship Channel/Galveston Bay (HSC/GB) prompted concerns over the extent and level of PFAS contamination. A targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based study of temporal and spatial patterns of PFAS associated with this incident revealed presence of 7 species; their levels gradually decreased over a 6-month period. Because the targeted LC-MS/MS analysis was focused on about 30 PFAS molecules, it may have missed other PFAS compounds present in firefighting foams. Therefore, we utilized untargeted LC-ion mobility spectrometry-mass spectrometry (LC-IMS-MS)-based analytical approach for a more comprehensive characterization of PFAS in these water samples. We analyzed 31 samples from 9 sites in the HSC/GB that were collected over 5 months after the incident. Our data showed that additional 19 PFAS were detected in surface water of HSC/GB, most of them decreased gradually after the incident. PFAS features detected by LC-MS/MS correlated well in abundance with LC-IMS-MS data; however, LC-IMS-MS identified a number of additional PFAS, many known to be components of firefighting foams. These findings therefore illustrate that untargeted LC-IMS-MS improved our understanding of PFAS presence in complex environmental samples.  相似文献   
45.
Aim of this study is to evaluate the protective role of Glycine max L. (soybean) against aluminum sulfate-induced genotoxicity. A diet containing 30% soybean and extracts obtained with various organic solvents were administered orally to male white Swiss mice prior to intraperitoneal injection of Al2(SO4)3. Light microscopy was used for the examination of genotoxicity involving somatic cells, germ cells, and sperms. The main secondary metabolites contained in each extract were isolated and identified by chromatographic and spectral analyses. Administration of soy diet and extracts to the examined mice induced significant anti-mutagenic activity against bone marrow aberrations and spermatocyte and sperm abnormalities. At the end of this study, maximum protection was achieved using the methanolic extract (83% and 79%) followed by those obtained with chloroform (71% and 49%) and n-hexane (51% and 39%) for bone marrow aberrations and spermatocyte abnormalities, respectively. The observed activity of soybean extracts might be related to the main constituents isolated and identified. These main constituents were the isoflavone glycosides genistin and daidzin in addition to saponins (methanol extract), lignan matairesinol (chloroform extract), and β-sitosterol, unsaturated fatty acids as well as phospholipids (n-hexane extract). The results illustrated that soy extracts can be considered as alternative anti-mutagenic nutraceuticals and promising source for developing anti-mutagenic drugs.  相似文献   
46.
An indirect competitive enzyme-linked immunosorbent assay (ELISA) has been developed and optimized for atrazine determination in soil at different depths (0-10, 10-20, and 20-30 cm) before and after 48 h of application, corn shoot and cow milk samples collected from Dina farm, Egypt. This assay was based on a specific polyclonal antibodies (PAb) raised by immunizing New Zealand rabbits with an immunogen prepared by coupling 3-{4-(ethylamino)-6-(isopropylamino)-1,3,5-triazine-2-yl} thiopropanoic acid to bovine serum albumin (BSA) via N-hydroxysuccinimide (NHS) active ester method. The sensitivity (estimated as IC?? value) was 17.5 μg mL?1 with a detection limit of 0.1 ng mL?1. The maximum atrazine concentration was found in soil especially in the deepest layer (325 and 890 μg kg?1 before and after application, respectively). Atrazine concentration in corn shoot was 333.28, μg kg?1 dry plant, while there was no detectable amount in milk. All samples screened by ELISA were validated by gas chromatography mass spectrometer procedure (GC/MS). Good correlation was achieved between the two methods (r = 0.997 for soil and 0.9814 for plant). This study demonstrates the utility and convenience of the simple, practical and cost-effective ELISA method in the laboratory for analysis of environmental samples. The method is ideal for the rapid screening of large numbers of samples in laboratories where access to GC/MS facilities, is limited or lacking.  相似文献   
47.
The behavior of chlorantraniliprole (CAP) and dinotefuran (DNF) insecticides was investigated in clay loam soil, a common type of the Egyptian soil. Effect of temperature, pH and particle size of the soil on the adsorption process was studied. Adsorption isotherm by bulk soil and its constituents; humic acid (HA), clay, silt and sand fractions was measured using batch equilibration technique. The results showed that the adsorption of the insecticides tested was significantly affected by the temperature and was a spontaneous interfacial process in the soil. Freundlich model accurately predicted the adsorption behavior of both insecticides. The interaction between soil and insecticides was endothermic and the highest adsorption for CAP and DNF was obtained at pH 9. However, the effect of pH on the adsorption of DNF was lower than that of CAP. Sorption of CAP and DNF on HA fraction was significantly greater than on clay fraction and bulk soil. In addition, the adsorption was significantly increased with particle size decrease. It could be inferred that the adsorption of CAP and DNF on clay loam soil was physical in nature and greatly influenced by the soil components, pH and temperature.  相似文献   
48.
The greater the use of energy in the transportation sectors, the higher the emission of carbon monoxide (CO), and hence inevitable harm to environment and human health. In this concern, measuring and predicting of CO emission from transportation sector—especially large cities—is important as it constitute 90 % of all CO emission. Many urban cities in developing world have not properly experienced such measurements or predictions. In this paper, for the first time, field measurements of traffic characteristics data and corresponding CO concentration have been performed for developing a model for predicting CO emissions from transportation sector for New Borg El Arab (NBC), Egypt. The performance of Swiss-German Handbook Emission Factors for Road Transport (HBEFA v3.1) model has been assessed for predicting the CO concentration at roadside in the study area. Results indicated that HBEFA v3.1 underestimate emission figures. The developed CO dynamic emission model involves the traffic flow characteristics with roadside CO concentrations. Acceptable representation of measured CO concentration has been shown by the developed dynamic CO emission model which introduces R 2?=?0.77, mean biases and frictional biases of ?0.27 mg m?3 and 0.09, respectively. A comparison between predicted CO concentrations using HBEFA v3.1 and the promoted dynamic model indicate that HBEFA v3.1 estimates CO emission concentrations in the study area with a mean error and frictional biases 159.26 and 233.33 %, respectively, higher than those of the developed model.  相似文献   
49.
Transition-metal coordination polymers [M(ndc)(bpy)·(H2O)m]·xH2O (where M = Co(II), Ni(II), Cu(II) and Zn(II), ndc = 1,4-naphthalenedicarboxylate, bpy = 4,4′-bipyridine; m = 0 or 1; x = 1 or 2) were prepared by reacting the ligands and metal ions at room temperature with the aid of microwave irradiation and sonication methods. The structure of the coordination polymers was assigned based on elemental analysis, FT-IR and electronic spectral studies, thermal analysis, scanning electron microscope and X-ray powder diffraction. Thermogravimetric analysis was also used to follow up the possible thermal decomposition steps and to calculate the thermodynamic parameters of the nano-sized metal complexes. The kinetic parameters were calculated making use of the Coats–Redfern and Horowitz–Metzger equations. All obtained results of the different technics used in our study stated the ability to synthesis the metal coordination polymers of our interest using both microwave irradiation and sonication methods.  相似文献   
50.
Seaweeds belonging to 14 different genera of Chlorophyta, Phaeophyta and Rhodophyta were analyzed to determine the levels of heavy metals in two areas of the Egyptian Red Sea coast. Among the trace metals analyzed, Mn and Zn showed the highest mass concentrations in the surface seawaters of the two studied areas. However, algae obtained from Suez area had the highest concentrations of the investigated heavy metals than those collected from Mars Alam area. Nevertheless, a high variability of the metal levels occurs among the studied algae and also between the investigated areas. Moreover, Zn was the most abundant metal in the seaweeds of the Suez area, while Pb was predominant in Mars Alam area in red and brown algae. L. farinosa had the highest average concentration factor of Zn in Suez (29161 fold), while it was 20091 fold in E. intestinalis at Mars Alam. The highest value of metal pollution index (MPI) was recoded in L. farinosa (22.0) at Suez. It represents 4.6 fold of that value recorded in L. farinosa at Mars Alam. Among green, brown and red algae in Suez, the highest values of MPI were recorded in Cladophora (mixed sub-species) and H. comuto (18.2 and 18.3), P. pavonia (16.2) and L. farinosa (22.1), respectively; while at Mars Alam, they were recorded in Cladophora (mixed sub-species) (6.6), P. pavonia (3.4) and L. farinosa (4.8), respectively.  相似文献   
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