The Effect of Neonicotinoids Exposure on Oreochromis niloticus Histopathological Alterations and Genotoxicity

This study aimed to examine the side effects of selected neonicotinoids (Acetamiprid, Aceta, and Imidacloprid, Imid) on Oreochromis niloticus juveniles. The acute toxicity, Probit method, revealed an LC₅₀ of 195.81 and 150.76 ppm for Aceta/96 h and Imid/72 h respectively. The fish were divided into three groups that were exposed, for 21 days (n?=?5/replicate), to 1/10 of the LC₅₀ of either neonicotinoids, however, the third was an unexposed control group. Results of erythrocytic micronucleus (MN), and nuclear abnormalities (NA) showed that Aceta and Imid exposure caused a significant (p?<?0.05) increase in MN by?~?2.2 and?~?10 folds, respectively relative to control. NAs occurred at the order of kidney-shaped?>?budding?>?binucleated in Aceta, however, budding?>?binucleated?>?kidney-shaped was noticed in the Imid group. Histopathological changes in gills, liver, and muscles were observed significantly in both exposed groups with more severity in the Imid group. Collectively, Aceta and Imid have potential genotoxicity and histopathological alterations in O. niloticus.

     

Contamination of Cows Milk by Heavy Metal in Egypt

The present investigation was carried out to assess the residues levels of five metals (Cadmium, Copper, Lead, Iron and Zinc) in cow milk collected from different sites in El-Qaliubiya governorate, Egypt. A total of 100 cow milk samples were collected from twenty cows in each location sites during the morning milking in the period from March to April, 2011. The highest average concentration are those of iron (16.38 μg/g) followed by zinc (10.75 μg/g) and lead (4.404 μg/g), while the lowest mean concentration are 2.836 and 0.288 μg/g for copper and cadmium, respectively. The results showed that most of the milk samples from the different sites containing all the studied metals with concentration higher than those recommended for milk by international dairy federation standard and Codex.     

Distribution of Heavy Metal Residues in Fish from the River Nile Tributaries in Egypt

The distribution patterns of some metals (zinc, iron, copper, cadmium and lead) in fish samples collected from El Menofiya Governorate, Egypt were studied. The samples were collected from El Menofiya, canal water supplies (El Sarsawia, El Bagoria and Bahr Shebin), in addition to El Embaby, El Menofi and Miet Rabiha drainage canals each 2 month during periods of 16 month, June 2007–Septemper 2008. In the present investigation, the high concentrations of metals were found in fish samples collected from the drainage canal. The highest mean concentration of lead (1.864 μg/g), copper (1.495 μg/g) and cadmium (1.840 μg/g) were found in fish samples collected from El-Embaby drain. While the highest mean concentration of iron (108.26 μg/g) and zinc (24.35 μg/g) were present in fish samples collected from Miet-Rabiha drain. Lead and cadmium were found in higher concentration than those recommended by FAO for fish.     

Level and Fate of Etoxazole in Green Bean (<Emphasis Type="Italic">Phaseolus vulgaris</Emphasis>)

The objective of this study was to estimate the total etoxazole residues balance (residue in pods, leaves and soil under the treated plant) in green bean and for identification of the degradative metabolites of etoxazole in soil under the treated plant. The results showed half life (t_1/2) values of 3.13, 2.73 and 2.11 days for etoxazole in green bean pods, leaves and soil, respectively. According to the maximum residue limits (MRL) the pre harvest intervals (PHI) of etoxazole on green bean pods was 4-days after the treatment. The results of GC–Ms analysis of soil extracts under the treated plant showed that, at zero time unchanged etoxazole was found. The proportion of etoxazole in soil extracts detected decreased with the time. GC–Ms analysis of soil extracts show the presence of compound having the formula of C₁₄H₂₃NO₂ which was suggested to be 2-amino-2(4-tert-butyl-2-ethoxyphenyl) ethanol. The other founded compound has the formula C₁₃H₁₈O₃ and suggested to be 4-tert-butyl-2-ethoxybenzoic acid.     

Correction to: A Preliminary Toxicology Study on Eco-friendly Control Target of Spodoptera frugiperda

Bulletin of Environmental Contamination and Toxicology - The original version of the article unfortunately contained a mistake in first author. Li-Kui Wang and Fen Li are co-first author in this...     

Simultaneous Determination of Spinetoram Residues in Tomato by High Performance Liquid Chromatography Combined with QuEChERS Method

A sensitive and simple method for simultaneous analysis of spinetoram residues and its dissipation in tomato were studied. Spinetoram residues were extracted from tomato samples with acetonitrile. The extract was cleaned-up with QuEChERS method by dispersive solid-phase extraction with primary secondary amine sorbent to remove co-extractives, prior to analysis by high performance liquid chromatography coupled with diode array detector (HPLC–DAD). This method is characterized by recovery >97 %, relative standard division (RSD) <12.3 %, and limit of quantification (LOQ) of 0.04 mg kg^?1, in agreement with directive for method validation in residue analysis. Also, the results showed that spinetoram dissipation pattern followed the first order kinetics with the half-life of 2.6 days, in tomato. The spinetoram residues in tomato were below the codex maximum residue level (0.06 mg kg^?1) after 10 days of application. This study suggests that spinetoram is acceptable to apply for tomato under the recommended dosage.     

Residue and Dissipation Dynamics of Lufenuron in Tomato Fruit Using QuEChERS Methodology

One field experiment was conducted with lufenuron (Match^® 5 % EC) on tomato crop during August 2011. The main objective was to understand the residue and dissipation behavior of insecticide lufenuron in tomato fruit samples. The dissipation behavior of lufenuron insecticide followed first-order rate kinetics at standard recommended dose application. The average initial deposit of lufenuron in tomato was observed to be 1.299 mg kg⁻¹at single application rate. This lufenuron residue dissipated to bellow LOQ of 0.03 mg kg⁻¹ 21 days after the treatment. Lufenuron residues were lost with pre-harvest intervals of 7 days, following application at the recommended dose by manufacture.

     

A Preliminary Toxicology Study on Eco-friendly Control Target of Spodoptera frugiperda

Pyrethroid and indoxacarb are commonly used pesticides to control the fall armyworm (Spodoptera frugiperda) in the crops. There are a series of consequences caused by the use of pyrethroid and indoxacarb pesticides under emergency control, such as pest resistance development, contamination of soil, water, and farm products. This study analyzed the structure and physiological function of the sodium channel in S. frugiperda, which is an important step to elaborate the resistance mechanism of S. frugiperda to indoxacarb and pyrethroid pesticides. According to genetic analysis, the cloned cDNA sequences of sodium channel in S. frugiperda (SfNa_v) showed the shortest genetic distance with that of the sodium channel in Helicoverpa armigera. Under the induction of three pesticides, the expression of SfNa_v decreased in the first 12 h and then increased after 24 h. It was concluded that SfNa_v had a typical structure of the sodium channel of insects and its down-regulated expression can decrease the combination of S. frugiperda with pyrethroid and indoxacarb pesticides. The up-regulated expression of SfNa_v was conducive to the enhancement of the pesticide resistance.

     

Organophosphorus Pesticides Residues in Fish Samples from the River Nile Tributaries in Egypt

The concentration of organophosphorus pesticides in fish samples from different tributaries of the Nile River in Egypt was monitored. Fish samples were collected from El Menofiya, canal water supplies (El-Sarsawia, El-Bagoria and Bahr Shebin), in addition to El-Embaby, El-Menofi and Miet Rabiha drainage canals each 2 month during periods of 16 month, June 2007–Septemper 2008. Chloropyrifos, cadusafos, diazinon, prothiphos and malathion were detected in fish tissues samples at level below the maximum residue limit. The highest average amount of chlorpyrifos (9.38 ng g⁻¹) and malathion (8.31 ng g⁻¹) were detected in El-Embaby drain. Prothiphos were found in tissues collected from El-Sarsawia canal and Miet-Rabiha drain at mean concentration of 4.91 and 6.55 ng g⁻¹, respectively. Diazinon was only found in one fish sample that collected from El-Menofi drain at the level of 9.23 ng g⁻¹.