Magnitude of cyantraniliprole residues in tomato following open field application: pre-harvest interval determination and risk assessment.

Cyantraniliprole is an anthranilic diamide insecticide, belonging to the ryanoid class, with a broad range of applications against several pests. In the presented work, a reliable analytical technique employing high-performance liquid chromatography coupled with photodiode array detector (HPLC-DAD) for analyzing cyantraniliprole residues in tomato was developed. The method was then applied to field-incurred tomato samples collected after applications under open field conditions. The latter aimed to ensure the safe application of cyantraniliprole to tomato and contribute the derived residue data to the risk assessment under field conditions. Sample preparation involved a single step extraction with acetonitrile and sodium chloride for partitioning. The extract was purified utilizing florisil as cleanup reagent. The developed method was further evaluated by comparing the analytical results with those obtained using the QuEChERS technique. The novel method outbalanced QuEChERS regarding matrix interferences in the analysis, while it met all guideline criteria. Hence, it showed excellent linearity over the assayed concentration and yielded satisfactory recovery rate in the range of 88.9 to 96.5%. The half-life of degradation of cyantraniliprole was determined at 2.6 days. Based on the Codex MRL, the pre-harvest interval (PHI) for cyantraniliprole on tomato was 3 days, after treatment at the recommended dose. To our knowledge, the present work provides the first record on PHI determination of cyantraniliprole in tomato under open field conditions in Egypt and the broad Mediterranean region.

Screening and assessing of pesticide residues and their health risks in vegetable field soils from the Eastern Nile Delta, Egypt.

The harmful effects of pesticide misuse on human health and the environment have become evident; so, this study aimed to monitor pesticide residues in soils of vegetable fields collected from the Eastern Nile Delta region, Egypt and to assess the potential health risks associated with them. Pesticide residues were determined using gas chromatography-mass spectrometry. Obtained results revealed that 100% of collected samples were contaminated with pesticides; residues of 33 compounds were detected in analyzed samples belonging to different chemical groups. Most detected pesticides (44%) were non-persistent and 40% were moderately persistent. While 1313% and 3% were persistent and very persistent compounds, respectively. Also, 36.7% and 30% of samples have two and three pesticides. Chlorpyrifos and propamocarb were the most dominant compounds that had widespread use across the study area. The number of detected pesticides per crop ranged from 1 to 16 (potato soil), followed by cucumber and tomato (13 pesticides), while one compound was detected in sweet potato soil. Soil organic matter content had a positive correlation with the total concentration of pesticide residues; however, no correlations were found with soil clay, pH and electrical conductivity contents. The human health risks of pesticides in the study soils were within acceptable levels. However, more attention should be paid in the future to decreasing the pesticide load and take place pesticide residue monitoring on vegetable soils.