D-002 is a new natural product consisting of a mixture of aliphatic fatty alcohols, which shows antioxidant and anti-ulcer effects in experimental models. A new validated methodology for determining simultaneously residual n-hexane and acetone in D-002 using the headspace gas chromatography (HS/GC) is described. The very poor solubility of D-002 in most solvents did necessary sample preparations in solid state. Limit test conditions allowed a detection of residual n-hexane and acetone more sensitively than that recommended for such purposes in the general method of the European Pharmacopoeia. Validation assays, applied to both D-002 residual solvents, proved: suitable sensitivity; very high linearity (correlation coefficients > or =0.999, R.S.D. of slopes < or =0.8% and R.S.D. of response factors < or =5% and no biases) and accuracy (average recoveries between 94.7 and 100.1%); and precision was < or =2.1%. The method was found suitable for quality control and stability studies of this new product.