Validation and application of a multiresidue method based on liquid chromatography-tandem mass spectrometry for evaluating the plant uptake of 74 microcontaminants in crops irrigated with treated municipal wastewater

tReuse of treated wastewater for agricultural purposes can mitigate water stress in some regions wherethe lack of water is an extended problem. However, the environmental long-term consequences of thispractice are still unknown. It is demonstrated that using reclaimed water for irrigation lead to accu-mulation and translocation of some microcontaminants (MCs) in soil and crops. However, so far, only asmall group of contaminants has been investigated. This study aims to develop and validate a simple andefficient multiresidue method based on QuEChERs (Quick, Easy, Cheap, Effective and Rugged) extractioncoupled to liquid chromatography tandem mass spectrometry (LC–MS/MS). The novelty of the studyrelays in the large number of MCs analyzed (74), some of them not previously investigated, in threecommodities (lettuce, radish and strawberry). Optimized conditions yielded good results for the threecommodities under study. Up to 84% of the compounds were recovered within a 70–120% range, withgood repeatability (relative standard deviations below 20% in most cases). Method detection (MDLs) andquantification limits (MQLs) ranged from 0.01 to 2 ng/g. The proposed method was successfully appliedto assess the potential uptake of MCs by lettuce and radish crops irrigated with wastewater under con-trolled conditions for 3 and 1.5 months, respectively. 12 compounds were detected in the crops withconcentrations ranging from 0.03 to 57.6 ng/g. N-Formyl-4-aminoantipyrine (4FAA) was the most con-centrated compound. The application of this method demonstrated for the first time the accumulation of5 contaminants of emerging concern (CECs) not previously reported: 4FAA, N-Acetyl-4-aminoantipyrine(4AAA), hydrochlorothiazide, mepivacaine and venlafaxine.