•GC–EI-MS/MS technique in statin analyses.•MRM in quantification.•Determination of statins in wood based fluids.•Hydrolysation of pine with Pleurotus ostreatus. Statins were separated and quantified with gas chromatography–mass spectrometry (GC–EI-MS/MS) using total ion monitoring (TIC) and multiple reactions monitoring (MRM). The MRM method in statins determination has a novelty value, since there are no previous studies on their simultaneous analysis in environmental or plant samples. The method development and optimization was challenging due to the physicochemical similarities of the silylated lovastatin, simvastatin, pravastatin, fluvastatin, and atorvastatin. The results showed that the use of MRM decreased their detection and quantification limits by factors of 2–10 compared to that obtained in TIC monitoring. The concentration calibration was made between 247.5ng/L and 9900ng/L. Limits of detection and quantification were between 50ng/L (lovastatin)–500ng/L (pravastatin) and 250ng/L (lovastatin)–1000ng/L (pravastatin), respectively. Based on the MRM results, the wood bark and phloem samples contained lovastatin, lovastatin–lactone, simvastatin, simvastatin–lactone, and pravastatin. Their concentrations were 250–3000μg/L, i.e. 4.2–50mg/kg in phloem and bark. However, they were not detected in fluids made with Pleurotus ostreatus fermentation of wood core.