In this study, an effective gas chromatography–tandem mass spectrometry method was developed to determine 47 pesticide residues in tea. Sample preparation involved a quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure, wherein the sample is extracted by acetonitrile and cleaned up with multiwalled carbon nanotubes and primary secondary amine adsorbents; dispersive liquid–liquid microextraction (DLLME) was subsequently performed using carbon tetrachloride as extractive solvent and the extract obtained by QuEChERS as dispersive solvent. Factors influencing DLLME efficiency, including type and volume of extractive solvent, volume of dispersive solvent, and extraction time were evaluated. For validation purposes, recovery studies were performed using matrix blanks fortified with pesticides at three concentrations, namely, 10, 50, and 100 μg kg−1. Most of the analytes were recovered at an acceptable range of 70‒120% and RSDs ≤ 20% were acquired for green tea, oolong tea, black tea, and puer tea. Limits of quantification of pesticides obtained for these teas were sufficiently low, and most pesticides levels were lower than 10 μg kg−1, which satisfies the requirements for maximum residue levels (MRLs) as prescribed by the European Community. Twenty-four commercially available tea samples were analyzed using this optimized method. Results revealed that the contents of chlorpyrifos and alpha-HCH from different green tea samples exceed the MRLs, and chlorpyrifos, bifenthrin, lambda-cyhalothrin, and cypermethrin are among the most frequently detected pesticides in teas.
Chromatographia – Springer Journals
Published: Jul 28, 2017
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera