Residue analysis, dissipation patterns of chlorfenapyr, diafenthiuron and their corresponding metabolites in tea trees, and dietary intake risk assessment

Abstract

BACKGROUND: Recently, chlorfenapyr and diafenthiuron have been widely used to prevent and control diseases and pests in tea production. However, rare studies have investigated the dissipation patterns of chlorfenapyr, diafenthiuron and their metabolites simultaneously in tea matrices. Here, we established an analytical method to investigate the degradation patterns of five target compounds in tea shoots and made tea samples. Moreover, the dietary intake risk assessment of chlorfenapyrdiafenthiuron mixture among Chinese populations was evaluated based on the supervised field experiment.RESULTS: The mean recoveries of the primary analytes at five spiking levels were between 95.6% and 112.6% in tea shoots and made tea, respectively, and the values of RSD (relative standard deviation) were lower than 9.7% for all the target analytes. The field trial results showed that the half-lives of chlorfenapyr and diafenthiuron based on the residue definition were 10.0-12.4 days and 4.3-5.9 days, respectively, in tea shoots. For the dietary intake risk assessment, the risk quotient (RQ) values in made tea ranged from 30.4% to 73.9% at the pre-harvest interval of 14 days, which were significantly less than 100%.CONCLUSION: The accuracy and precision of the developed method were satisfied by the measurement requirements according to the validation results. The dynamic dissipation experiments suggested that diafenthiuron was much easier to dissipate than chlorfenapyr. Moreover, the existence of tralopyril made the half-life of chlorfenapyr significantly increase, indicating that practical application of chlorfenapyr should take careful consideration of its metabolite. Finally, the potential chronic dietary risks of the chlorfenapyr-diafenthiuron mixture to human communities were within the acceptable range.

Traceable and Integrated Pesticide Screening (TIPS), a Systematic and Retrospective Strategy for Screening 900 Pesticides and Unknown Metabolites in Tea

“…However, diafenthiuron is easily degraded to diafenthiuron–urea and diafenthiuron–methanimidamide in plants, which are considered to have higher toxicity than the parent pesticides. These metabolites accumulate in the lung and liver, thereby threatening human health . Wu et al indicated that the chronic hazard quotient of diafenthiuron and its metabolites was high and caused an unacceptable health risk to tea consumers due to the high residue and low ADI, even though there was a lower transfer rate in tea infusion.…”

“…These metabolites accumulate in the lung and liver, thereby threatening human health. 57 Wu et al 41 indicated that the chronic hazard quotient of diafenthiuron and its metabolites was high and caused an unacceptable health risk to tea consumers due to the high residue and low ADI, even though there was a lower transfer rate in tea infusion. In addition, these metabolites could be detected after 21 days, revealing that they were persistent in tea plants.…”

Development of a gold nanoparticle-based lateral flow immunoassay for the fast detection of diafenthiuron in cabbage and apples

“…8 Moreover, in mammals the decomposition products of DIAF are toxic to target organs such as the liver and lungs, and the widespread use of DIAF will inevitably lead to environmental pollution and threaten human health. 9,10 Cabbage is a widely used and popular cruciferous vegetable, which is also an important ingredient in Chinese sauerkraut. 11,12 Apples are a rich source of bioactive compounds and micronutrients that are essential for a normal diet.…”

Identification and biocontrol potential evaluation of a naturally occurring Metarhizium pingshaense isolate infecting tea weevil Myllocerinus aurolineatus Voss (Coleoptera: Curculionidae)

“…Tea weevils are currently controlled primarily via the application of chemical insecticides. However, using chemical insecticides may lead to an increased risk of pesticide residues in tea and tea products (Xu et al 2022). In addition, some of these chemicals are potentially harmful to non-target beneficial organisms, with inevitable detrimental effects on the environment (Sutar et al 2022).…”