Application of Nemacur in Gaza strip increased rapidly as a potential alternative to the widely used soil sterilizing agent methyl bromide. Nemacur application may contaminate soil, water and plant systems due to its ...Application of Nemacur in Gaza strip increased rapidly as a potential alternative to the widely used soil sterilizing agent methyl bromide. Nemacur application may contaminate soil, water and plant systems due to its high solubility in water. The objective of this study was to determine Nemacur residues soil, water, and cucumber samples collected from a field plots applied Nemacur at different field rates (0.0, 0.5 F, 1 F, 2 F) where F is the recommended field rate of Nemacur (4 kg/Hectare). Nemacur residues were determined by chemo-assay and bioassay techniques. Results revealed that considerable Nemacur concentrations were found in cucumber fruits and plant leaves. Nemacur residues were higher in water samples collected from sandy soil (7.2 μg/L) than from clay soil (3.4 μg/L). Furthermore, Nemacur residues in sandy soil (0.23 μg/kg) were lower than those in clay soil (1.3 μg/kg). In addition, Nemacur concentration in top soil layer in clay soil was lower than other layers. Nemacur residues in cucumber fruits grown in sandy soil were lower than those in cucumber fruits grown in clay soil. Nemacur residues in cucumber fruits collected from the market were below detection limit of HPLC technique. Chemo-assay techniques determined lower concentration of Nemacur than bioassay techniques. It can be concludes that considerable concentrations of Nemacur were found in all tested samples. Comparing with maximum residues limits (MRLS). Nemacur concentrations in various environmental samples were less than the maximum residues limits.展开更多
Application of Nemacur (Fenamiphos) for pest control may contaminate soil, water and plant with harmful residues and pose threats to human life. This study developed an easy method for the determination of Nemacur res...Application of Nemacur (Fenamiphos) for pest control may contaminate soil, water and plant with harmful residues and pose threats to human life. This study developed an easy method for the determination of Nemacur residues in cucumber fruits collected from the central markets and from the farm. The method is based on extracting the active ingredients of Nemacur from the commercial formulation and used as a standard material to calibrate the HPLC to determine Nemacur residues in cucumber fruits collected from the central market. Results showed that more than 70% of the active ingredient was extracted from the commercial formulations. Standardization of HPLC with extracted materials showed strong positive association between concentration and peak area relationship. Bioassay investigation showed high mortality of tested organism (fish). Statistical analysis of mortality % between the commercial formulation and those of the extracted ingredient showed no significant differences. These results demonstrated the effectiveness of extracted Nemacur to calibrate HPLC and in bioassay test. Nemacur residues in Cucumber fruits collected from the market were below the detection limit of HPLC, recovery % of Nemacur from control group of cucumber was above 80%. It can be concluded that the method is easily developed and validated by bioassay and chemo-assay.展开更多
文摘Application of Nemacur in Gaza strip increased rapidly as a potential alternative to the widely used soil sterilizing agent methyl bromide. Nemacur application may contaminate soil, water and plant systems due to its high solubility in water. The objective of this study was to determine Nemacur residues soil, water, and cucumber samples collected from a field plots applied Nemacur at different field rates (0.0, 0.5 F, 1 F, 2 F) where F is the recommended field rate of Nemacur (4 kg/Hectare). Nemacur residues were determined by chemo-assay and bioassay techniques. Results revealed that considerable Nemacur concentrations were found in cucumber fruits and plant leaves. Nemacur residues were higher in water samples collected from sandy soil (7.2 μg/L) than from clay soil (3.4 μg/L). Furthermore, Nemacur residues in sandy soil (0.23 μg/kg) were lower than those in clay soil (1.3 μg/kg). In addition, Nemacur concentration in top soil layer in clay soil was lower than other layers. Nemacur residues in cucumber fruits grown in sandy soil were lower than those in cucumber fruits grown in clay soil. Nemacur residues in cucumber fruits collected from the market were below detection limit of HPLC technique. Chemo-assay techniques determined lower concentration of Nemacur than bioassay techniques. It can be concludes that considerable concentrations of Nemacur were found in all tested samples. Comparing with maximum residues limits (MRLS). Nemacur concentrations in various environmental samples were less than the maximum residues limits.
文摘Application of Nemacur (Fenamiphos) for pest control may contaminate soil, water and plant with harmful residues and pose threats to human life. This study developed an easy method for the determination of Nemacur residues in cucumber fruits collected from the central markets and from the farm. The method is based on extracting the active ingredients of Nemacur from the commercial formulation and used as a standard material to calibrate the HPLC to determine Nemacur residues in cucumber fruits collected from the central market. Results showed that more than 70% of the active ingredient was extracted from the commercial formulations. Standardization of HPLC with extracted materials showed strong positive association between concentration and peak area relationship. Bioassay investigation showed high mortality of tested organism (fish). Statistical analysis of mortality % between the commercial formulation and those of the extracted ingredient showed no significant differences. These results demonstrated the effectiveness of extracted Nemacur to calibrate HPLC and in bioassay test. Nemacur residues in Cucumber fruits collected from the market were below the detection limit of HPLC, recovery % of Nemacur from control group of cucumber was above 80%. It can be concluded that the method is easily developed and validated by bioassay and chemo-assay.
