Persistence of α-cypermethrin residues in milk of lactating donkeys (Equus asinus) using UHPLC-MS/MS

Abstract

The aim of this study was to measure the persistence of residues of the pyrethroid insecticide α-cypermethrin (ACYP) in the milk of lactating donkeys following pour-on treatment. Milk was collected from animals (n = 7) before the treatment and at 12, 24, 36, 48, 60, 72 and 84 h post-treatment. The last sampling was taken 7 days post-treatment (168 h). Milk samples were analysed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The analytical method was validated following requirements of Commission Decision 2002/657/EC. All samples showed levels of ACYP below the maximum residue limit (MRL) of 20 μg kg⁻¹ established for bovine milk (Commission Regulation (EU) No. 37/2010). The results demonstrate that there is minimal partitioning of ACYP into milk in lactating donkeys from pour-on treatment.

Graphical Abstract

Keywords:

• alpha-cypermethrin
• residues
• depletion
• milk
• donkeys
• HPLC-MS/MS

Funding

This work was supported by the Compagnia San Paolo Bank, the Pole of Science and Technology for Life (FARO Project, 2012) and POR Campania FSE 2007–2013 (Project CARINA). No author had a financial or personal relationship with people or organisations that could inappropriately influence or bias the content of this paper.