Cellular metabonomics-particularly using mass spectrometry-shows great promise as a technique to evaluate the response of biological systems to toxic insult.We have been developing shotgun lipidomic assays via ultra-high resolution mass spectrometry for analyzing the effect of toxic insult to cells in culture.Lipidomics-a variety of metabonomics-is well-suited to analysis by mass spectrometric techniques, due to the ease of lipid extraction and the high response of lipids in electrospray mass spectrometry.Because there is little known about the lipid profiles expected for different cell types, our first goal was to determine a baseline profile for the rat lung macrophage cell line we were using.We have been making use of the Van Krevelen diagram (H/C vs. O/C ratios) to graphically display the lipid profiles thus generated.A typical van Krevelen diagram representing the negative ion mode scan of control macrophage lipid extract is shownbelow (with color representing peak intensity).

The two major modes of cell death include apoptosis and necrosis. Some chemical compounds, Iike Staurosporine and Spermine-NONO-ate, are known to induce apoptosis or necrosis, respectively.We have been comparing the effects of a number of toxic compounds to the effects generated by the two positive control chemicals with known cell death mechanisms. The quinone compounds we are using were chosen to represent compounds which may be present in the oxidized condensed aromatic fraction of airborne particulate matter, based on previous conclusions from concentration curve comparisons.