Skip to Content
Merck
  • Simultaneous extraction and determination of various pesticides in environmental waters.

Simultaneous extraction and determination of various pesticides in environmental waters.

Journal of separation science (2014-10-02)
Zulin Zhang, Thibault Lefebvre, Christine Kerr, Mark Osprey
ABSTRACT

A simple and rapid method was developed for the simultaneous analysis of nine different pesticides in water samples by gas chromatography with mass spectrometry. A number of parameters that may affect the recovery of pesticides, such as the type of solid-phase extraction cartridge, eluting solvent in single or combination and their volumes, and water pH value were investigated. It showed that three solid-phase extraction cartridges (Strata-X, Oasis HLB, and ENVI-18) produced the greatest recovery while ethyl acetate/dichloromethane/acetone (45:10:45, 12 mL) followed by dichloromethane (6 mL) was efficient in eluting target pesticides from solid-phase extraction cartridges. Different water pH values (4-9) did not show a significant effect on the pesticides recovery. The optimized method was verified by performing spiking experiments with a series of concentrations (0.002-10 μg/L) in waters, with good linearity, recovery, and reproducibility for most compounds. The limit of detection and limit of quantification of this optimized method were 0.01-2.01 and 0.02-6.71 ng/L, respectively, much lower than the European Union environmental quality standard for the pesticides (0.1 μg/L) in waters. The proposed method was further validated by participation in an interlaboratory trial. It was then subsequently applied to river waters from north-east Scotland, UK, for the determination of the target pesticides.

MATERIALS
Product Number
Brand
Product Description

Supelco
Acetone, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
Atrazine-d5, PESTANAL®, analytical standard
Supelco
Chlorpyrifos, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland
Sigma-Aldrich
Methanol, NMR reference standard
Sigma-Aldrich
Sodium azide, ReagentPlus®, ≥99.5%
Sigma-Aldrich
Sodium azide, BioXtra
Supelco
Methanol, analytical standard
Supelco
Acetone, analytical standard
Supelco
Isoproturon, PESTANAL®, analytical standard
Sigma-Aldrich
Sodium azide, BioUltra, ≥99.5% (T)
Supelco
α-Cypermethrin, PESTANAL®, analytical standard
Sigma-Aldrich
Methanol, anhydrous, 99.8%
Sigma-Aldrich
Acetone, suitable for HPLC, ≥99.9%
Supelco
Chlorpyrifos, PESTANAL®, analytical standard
Sigma-Aldrich
Acetone, ≥99%, meets FCC analytical specifications
Sigma-Aldrich
Acetone, natural, ≥97%
Sigma-Aldrich
Sodium azide, purum p.a., ≥99.0% (T)
Sigma-Aldrich
Methanol, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥99.8% (GC)
Sigma-Aldrich
Methanol, puriss., meets analytical specification of Ph Eur, ≥99.7% (GC)
Sigma-Aldrich
Acetone, histological grade, ≥99.5%
Sigma-Aldrich
Methanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Acetone, ACS reagent, ≥99.5%
Sigma-Aldrich
Acetone, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥99.5% (GC)
Sigma-Aldrich
Acetone, ACS reagent, ≥99.5%
Sigma-Aldrich
Methanol, Absolute - Acetone free
Sigma-Aldrich
Methanol, ACS spectrophotometric grade, ≥99.9%
Sigma-Aldrich
Methanol, Laboratory Reagent, ≥99.6%
Sigma-Aldrich
Methanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Methanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Acetone, Laboratory Reagent, ≥99.5%