An Alternative Strategy for Screening and Confirmation of 330 Pesticides in Ground- and Surface Water Using Liquid Chromatography Tandem Mass Spectrometry

Abstract

The presence of pesticide residues in water is a huge worldwide concern. In this paper we described the development and validation of a new liquid chromatography tandem mass spectrometric (LC-MS/MS) method for both screening and quantification of pesticides in water samples. In the sample preparation stage, the samples were buffered to pH 7.0 and pre-concentrated on polymeric-based cartridges via solid-phase extraction (SPE). Highly sensitive detection was carried out with mobile phases containing only 5 mM ammonium formate (pH of 6.8) as an eluent additive and using only positive ionization mode in MS/MS instrument. Hence, only 200-fold sample enrichment was required to set a screening detection limit (SDL) and reporting limit (RL) of 10 ng/L. The confirmatory method was validated at 10 and 100 ng/L spiking levels. The apparent recoveries obtained from the matrix-matched calibration (5–500 ng/L) were within the acceptable range (60–120%), also the precision (relative standard deviation, RSD) was not higher than 20%. During the development, 480 pesticides were tested and 330 compounds fulfilled the requirements of validation. The method was successfully applied to proficiency test samples to evaluate its accuracy. Moreover, the method robustness test was carried out using higher sample volume (500 mL) followed by automated SPE enrichment. Finally, the method was used to analyze 20 real samples, in which some compounds were detected around 10 ng/L, but never exceeded the assay maximum level.

Development of a Novel LC-MS/MS Multi-Method for the Determination of Regulated and Emerging Food Contaminants Including Tenuazonic Acid, a Chromatographically Challenging Alternaria Toxin

“…In the analysis of pesticides and mycotoxins, the HPLC separation is generally done under acidic pH or sometimes at neural pH conditions [ 12 , 37 , 38 ]. In contrast, the separation of alkaloids and the Alternaria toxins requires alkaline pH conditions in the eluent recommended by the standards [ 19 , 25 , 26 ].…”

“…In our earlier studies, we found that the mobile phase did not require acidic conditions to obtain high sensitivity for the analysis of pesticides and mycotoxins using LC-MS/MS separation and employing positive ionization [ 37 , 39 ]. The response of DON, aflatoxins and some pesticides (e.g., chlorpyrifos-ethyl/methyl), detected as a protonated molecule ion, slightly increased at alkaline pH in comparison with acidic conditions ( Figure 2 ).…”

Assessment of the Population Risk Because of Leaching From the Soil Into Groundwater of Various Groups of Pesticides Recommended for the Protection of Berry and Melon Crops in the Private Farms of Ukraine

“…Згідно чинного законодавства в Україні 3,4,5 кожний громадянин має право на споживання безпечних харчових продуктів, питної води та ін.…”

“…Однак широке використання пестицидів також означає, що вони з'являються та накопичуються в ґрунті, глині або у зразках води через гідрофобність молекул 6 та можуть негативно впливати на здоров'я населення при споживання контамінованої пестицидами води 7 .…”

Sensitive determination of 4,6-dinitro-o-cresol based on a glassy carbon electrode modified with Zr-UiO-66 metal–organic framework entrapped FMWCNTs

“…Development of fast, easy, and less expensive methods for pesticide detection is gaining significant research focus nowadays owing to the emergent need to check the degradation of the environment as well as to protect human health. 1 Traditionally pesticides are detected by different instrumental techniques such as GC, 2 HPLC, 3 LC-MS, 4,5 GC-MS, 6 etc. However, these methods, although reliable, require time-consuming work-up steps, costly equipment, and trained personnel to run the equipment and hence are not adapted for routine analysis and field deployment.…”