Highly sensitive analytical method for herbicide clopyralid residue in cattle manure compost with ultraperformance liquid chromatography tandem mass spectrometry

Abstract

A micro liquid-liquid extraction has been applied to sample preparation in the current authorized method for clopyralid in compost. The method rendered matrix effects practically negligible during determination with ultraperformance liquid chromatography-electrospray ionization tandem mass spectrometry with an improved limit of quantification of 0.7 µg/kg dry weight. Moreover, it had good accuracy and reproducibility. Therefore, the method is proposed as a highly effective routine analytical technique for investigating the actual status of clopyralid residue in compost.

Change of clopyralid concentration in recycled beef cattle compost

“…To analyze clopyralid in raw material or compost, material was dried at 40℃ for 2 days and ground to less than 0.5 mm so that a sample could be extracted with methanol under alkali conditions. The sample extracts were cleaned with cartridges of a copolymer (Oasis HLB; Waters Corp.) and a micro‐liquid–liquid extraction, using dichloromethane (Wako Pure Chemical Industries Ltd.) and then analyzed by liquid chromatography‐tandem mass spectrometry, LC‐MS/MS (LC: Agilent 1,200 Infinity Series, MS/MS: Agilent 6,460 Triple Quad LC/MS; Agilent Technologies, Inc.) (Watanabe et al., 2019). Preparation of samples was conducted by the authors, and extraction, cleaning up, and analyzing were consigned to a private analytical institution (Miura Co., Ltd., Matsuyama, Japan).…”

“…The above Japanese manual and related authorities instruct emphatically that compost application needs to be reduced according to the clopyralid concentration of the compost or the sensitivity of crops to clopyralid and that compost application should be abandoned in some cases (MAFF, 2018a; NARO, 2009). In addition, bioassays for residues in soil or compost that investigate physiological responses of leguminous plants (Fauci et al., 2002; Sato et al., 2010) and a highly sensitive chemical analysis for clopyralid in compost have been developed recently (Watanabe et al., 2019).…”

The Influence of Herbicides to Marine Organisms Aliivibrio fischeri and Artemia salina

“…It is often found in drinking water [59], even at higher concentrations than the permitted value (0.1 µg•L −1 ) for this pesticide [60]. Clopyralid residues were also found in several crops grown on soil contaminated with this herbicide [61] and has also been detected in processed cereals, such as wheat or barley bran; great attention is paid to its accumulation in compost [62][63][64][65].…”