Dissipation kinetics and processing behavior of boscalid and pyraclostrobin in greenhouse dill plant (Anethum graveolens L.) and soil.

BACKGROUND Determining the environmental behavior and fate of chemical compounds during technological processing of plants is a task of great significance nowadays. However, the current knowledge is still incomplete for unique herbal matrices belonging to minor crops. The research presents, for the first time, the dissipation kinetics and processing behavior of carboxamide boscalid (BOS) and stobilurin pyraclostrobin (PYR) fungicides during greenhouse dill (Anethum graveolens L.) cultivation. RESULTS The half-lives (t1/2) of BOS and PYR after application at the recommended and double dosage were in the range: 1.62-2.01 days in plant and 2.08-4.85 days in soil, respectively. The processing behavior in dill was estimated after washing, hot air drying and drying in sunlight without/with pretreatment. Processing factors (PFs) were above 1 after drying (PF= 1.24-1.39 hot air; PF=1.15-1.28 sunlight) and below this value when the washing step was applied (PF=0.31-0.42 hot air; PF=0.21-0.34 sunlight), indicating the highest effectiveness of reduction, up to 73% BOS and 79% PYR. CONCLUSION BOS/PYR residues at pre-harvest intervals after both doses were below EU MRLs. The highest effectiveness was noted for drying carried out with the washing step, which has a great influence on the concentration of residues in the final product. The findings can supplement PF databases not set for minor crops and can be used to establish MRLs and determine human exposures more accurately in risk assessment studies. This article is protected by copyright. All rights reserved.