Analysis of alcohol ethoxylates and alkylamine ethoxylates in agricultural soils using pressurised liquid extraction and liquid chromatography?mass spectrometry

Abstract

Nonionic surfactants e.g. alcohol ethoxylates (AEOs) and alkylamine ethoxylates (ANEOs) are commonly utilised as adjuvants in pesticide formulations to enhance their effectiveness. In this study, analytical methods for AEO and ANEO determination in soil samples using pressurised liquid extraction (PLE) were developed and used in connection with LC-MS. The recovery of the method, which was highly dependent on the soil properties, varied in the range 47-106% for AEO and 27-109% for ANEO. Detection limits (LOD) were 7-13 microg kg(-1) for AEO and 24-43 microg kg(-1) for ANEO. The developed method has been applied to determine AEOs and ANEOs in surface soil samples from fields sprayed with glyphosate herbicides. Tallowalkylamine ethoxylates (an ANEO) were detected in the soil before and after pesticide application, with increasing concentrations after treatment. The highest concentration in the soil samples was observed for the ANEO homologues with the longest ethoxy chains; in the clay soil the concentration decreased with the length of the ethoxy chain. ANEOs added to pesticide formulations as a technical mixture will, as demonstrated in this study, behave as individual homologues, which is reflected in their behaviour in the environment.

Determination of dodecanol and ethoxylated fatty alcohols from environmental samples using diatomaceous earth as a green sorbent for solid-phase extraction

“…In both variants the obtained recovery rates of C 12 OH and C 12 EO 1‐9 ranged between 33 and 99%, and were comparable to the results reported by Krogh et al. .…”

“…In this case the results obtained for both studied sorbent-eluent systems were comparable. In both variants the obtained recovery rates of C 12 OH and C 12 EO 1-9 ranged between 33 and 99%, and were comparable to the results reported by Krogh et al [44,45].…”

“…Krogh et al. obtained recovery rates of 48–103% for C 12 EO 3‐9 in spiked water and 39–69% in spiked ground water. In this case the extraction was carried out using a Porapak RDX (divinylbenzene‐vinylpyrrolidone, Waters, Miliford) column with a methanol/acetonitrile (1:2) elution mixture .…”

Analysis of Surfactants in Environmental Samples by Chromatographic Techniques

“…Solid samples (sewage sludges, soils or sediments) are also kept at low temperature once they are collected to avoid any degradation of the analytes during the transport to the laboratory. Later, they are usually dried in a heater [47], at room temperature [25], or frozen at -20 ºC and later freeze-dried [48]. Once dried, samples are milled and strained through a sieve to a particle size of less than 2 mm, and then stored at 4 to -20 ºC for further extraction and analysis.…”

Determination of Dodecanol and Short‐Chained Ethoxylated Dodecanols by LC–MS/MS (with Electrospray Ionization) After Their Derivatization (with Phenyl Isocyanate)

“…Different detectors can be used for determination of ethoxylated surfactants. The most popular are the ultraviolet detector (UV) [15][16][17], fluorescence detector [10,18], flame ionization detector (FID) [19], evaporative lightscattering detector (ELSD) [20,21], corona-charged aerosol detector (CAD) [1], MS detector and MS/MS detector [6,11,18,[22][23][24][25][26].…”