Subcutaneous fat samples from 25 workers in a styrene polymerization plant have been analyzed for styrene, ethyl benzene, toluene, benzene, and benzaldehyde by gas chromatography. Styrene was found in samples from 13 of 17 workers who had been heavily exposed within the previous 3 days, 5 of 13 having been exposed 2-3 days earlier. Six workers 4-90 days removed from exposure and two 2-3 days removed from low (less than 5 ppm) exposures had no detectable styrene in fat tissue samples. Toluene and ethyl benzene were found in varying amounts in many samples, and benzene was observed in three samples. Benzaldehyde was observed at levels of 5-53 microng/g in all samples. Although urinary metabolites and breath levels of styrene are reported to be detectable for less than 24 hr following exposure, styrene was found in subcutaneous fat from the subjects of this study for as long as 3 days after the most recent occupational exposure. The combination exposures in such a setting are reflected in the variety of hydrocarbons found in fat samples of workers.