Fossil fuel biomarkers in plant waxes as pollution parameters

Hopane and sterane derivatives typical of highly mature sedimentary organic matter, e.g. petroleum, have been identified in several plant species growing near Nancy, France. Analyses of plant waxes by gas chromatography–mass spectrometry over a restricted mass interval (m/z 185–195) allows definition of pollution parameters based on the relative concentration of fossil hopanes versus modern plant n-alkanes. Indeed, such parameters are higher for Pinus nigra growing along a high traffic highway than for Pinus nigra growing in a less polluted suburb area. Molecular pollution parameters based on fossil molecules are thus promising tools for measuring the extent of fossil fuel input into plant and food.