A micro-scale analytical method combined with PTV-GC–MS to determine polycyclic aromatic hydrocarbons in human lungs

Abstract

The analysis of polycyclic aromatic hydrocarbon (PAH) in human lungs is a challenge, due to low amount of target analytes, low amount of available sample and complexity of the matrix. In this study, a micro-scale analytical method is proposed to determine PAH in human lungs. The method employs micro-scale extraction, clean-up, and programmable temperature vaporisation-gas chromatography-mass spectrometry (PTV-GC–MS) analysis. The sample treatment was minimized. PTV was an excellent option to introduce up to 50 µL with a variation of <10%. Determination coefficients (r2) ranged from 0.967 for acenaphthene to 0.996 for indeno[1,2,3-cd]pyrene (p < 0.05). Instrumental detection limits were between 100 fg µL−1 (benzo[a]pyrene) and 5 pg μL−1, for acenaphthylene; the method detection limits were between 100 pg g−1 (indeno[1,2,3-cd]pyrene) and 6.7 ng g−1 (pyrene). Recovery ranged from 46 ± 12% (indeno[1,2,3-cd]pyrene) to 79 ± 16% (benzo[e]pyrene) with ≤5 ng of PAH, and between 82 ± 15% (acenaphthylene) and 98 ± 7% (benzo[k]fluoranthene) with ~10 ng of PAH in the lungs. The Analytical Eco-Scale metric classified our methodology as an acceptable green analysis. The analytical method was applied to determine PAH in real lung samples. No PAH were found in any sample. Cholesterol and derivatives, in addition to palmitic and oleic acid, were the most abundant compounds. Our proposal is a microscale, green and sensitive method to determine PAH levels in human lung tissues.