A quantitative method to assay accumulated polychlorobiphenyls (PCB) in Rho
notorula glutinis is described which avoids any interference of extracellul
ar adsorbed compounds. This method is based on a prior appropriate treatmen
t of the cells before the extraction of derivatives by supercritical CO2 an
d GC analysis. The prior treatment consists in a double fixation of the sam
ples with glutaraldehyde and osmium tetroxyde. After this fixation process
the elimination of the extracellular PCBs can be achieved by washing the fi
xed yeast cells with organic solvents.