QuEChERS Extraction and PAHs Analysis

Acetone, n-hexane of analytical grade, and petroleum ether for GC were obtained from Chempur, Poland. Salts used for extraction using the QuEChERS method included sodium chloride, magnesium sulfate, disodium citrate sesquihydrate, trisodium citrate (Chempur, Poland), together with sorbents used for clean-up – primary and secondary amines, PSA (Agilent, USA), and magnesium sulfate (Chempur, Poland). A certified mixture of standard solutions, EPA 525 PAHs Mix B, was obtained from Sigma-Aldrich, USA. Furthermore, methanol LC-MS (Honeywell, USA), 2,3,5-triphenyltetrazolium chloride – TTC (Sigma-Aldrich, USA) and 1,3,5-triphenyl tetrazolium formazan – TPF (Tokyo Chemical Industry, Japan) were used for the DHA analysis.