Large-scale fate profiling of butralin between cultivated and processed garlics for multi-risk estimations

Insights into the Occurrence, Distribution and Dissipation of Widespread Agrochemicals in Celery Agrosystems for Joint Risk Assessment

Elucidating exposure risks associated with the most widely used agrochemicals and their metabolites in celery agrosystems are vital for food safety and human health. The occurrence, distribution, dissipation and metabolism of imidacloprid (IMI), acetamiprid (ACE), thiamethoxam (THM) and difenoconazole (DIF) in celery tissues reflected by initial depositions, uptake characteristics, half-lives, concentration variations. DIF exhibited unacceptable ecological risk to soil organisms under multi-risk evaluation models, including toxicity exposure ratio, risk quotient, and BITSSD model. The joint dietary risks of target pesticides were 37.273-647.454% and 0.400-2522.016% based on deterministic and probabilistic models, with non-carcinogenic risks of 30.207-85.522% and 1.229-2524.662%, respectively. Children aged 1-6 years suffered the highest exposure, with the leaves posing higher risk than other tissues. Long-term exposure risks should be continuously assessed for ecological sustainability and human health, given the widespread usage and cumulative effects of target pesticides, especially for rural children.

Dissipation behavior and risk assessment of imidacloprid and its metabolites in apple from field to products

Pesticides play vital roles in controlling pests and boosting crop yields. Imidacloprid is widely used all over the world and may form in agricultural products. The presence of pesticide residues in apples raises serious health concerns. Understanding the residual fate of imidacloprid is critical for food safety and human health. In this study, the dissipation behavior, metabolism, household processing and risk assessment of imidacloprid and its metabolites in apple were investigated from filed to products. Field experiment results suggested that the half-lives of imidacloprid at 5 times the recommended dosage was 1.5 times that of the standard dosage. And the final residues of imidacloprid were less than the established maximum residue limits (MRLs). Clarification and simmering had little effect on the reduction the residues of imidacloprid and its metabolites. The calculated processing factors were lower than 1 for imidacloprid and its metabolites, implying that the residual ratios of imidacloprid and its metabolites in each steps of the food processing were reduced. The risk quotients were <1 for all Chinese people, indicating that acceptable risks associated with dietary exposure to imidacloprid in apple. However, the higher risks were observed in young people than adults, and females faced higher risks than males. Given high residue levels in pomace, imidacloprid and its metabolites should be further studied in commercial byproducts.

Comprehensive effects of thiamethoxam from contaminated soil on lettuce growth and metabolism

The second-generation neonicotinoid thiamethoxam, is prevalent in soils because of its extensive application and persistence. However, the comprehensive effects of thiamethoxam residue in soils on cultivated plants are still poorly understood. This study examined variations of growth state, physiological parameters, antioxidant activity, and metabolites in lettuce after thiamethoxam exposure; the removal effects of different washing procedures were also investigated. The results indicated that thiamethoxam in soils significantly increased the fresh weight, seedling height and chlorophyll content in lettuce, and also altered its lipid, carbohydrate, nucleotide and amino acids composition based on untargeted metabolomics. KEGG pathway analysis uncovered a disruption of lipid pathways in lettuce exposed to both low and high concentrations of thiamethoxam treatments. In addition, the terminal residues of thiamethoxam in lettuce were below the corresponding maximum residue limits stipulated for China. The thiamethoxam removal rates achieved by common washing procedures in lettuce ranged from 26.9% to 42.6%. This study thus promotes the understanding of the potential food safety risk caused by residual thiamethoxam in soils.