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A simple and rapid capillary gas chromatography (GC) method is described for the quantitative determination of 2,6-di-tert-butyl-4-"methylphenol (BHT) antioxidant in soap bars, fatty acids, and related intermediates. The procedure involves blending the sample with dimethylformamide in the presence of 2,4-di-tert-butylphenol (DTBP) internal standard, filtering the mixture, silylating an aliquot with BSTFA (bis-trimethylsilyltrifluoroacetamide) and quantifying by capillary GC using flame ionization detection. The silyl derivatization and nonpolar capillary column (12 m, methyl silicone, fused silica) provided resolution of BHT from certain fragrance component interferences. The method has a detection limit of approximately 10 ppm. Soaps fortified with BHT showed recoveries of 97.1 -+ 3.7% at the 200 ppm level and 92.3 -+ 2.2% when spiked at the 75 ppm level. The effect of bar soap storage time on BHT content is also demonstrated.

A colorimetric method has been developed, suitable for determining low levels (10–200 ppm) of phosphorous in detergent formulations containing large amounts of silicate. Samples are ashed to remove organic matter, hydrolyzed to convert all phosphates to ortho‐phosphate, and centrifuged to remove any SiO2, carbon or other solids. Phosphomolybdic acid is formed and extracted into an organic solvent, where it is reduced to the classic molybdenum blue color by stannous chloride. The procedure yields accurate and reproducible results, with reliability at the 25 ppm phosphorous level of ±3 ppm.

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Methodology is described for the determination of very low levels (~< 100 ng/ml) of triclocarban and triclosan in blood. The technique involves the use of a special continuous distillation extraction apparatus for separating these bacteriostats from blood in a relatively selective and automatic manner. In this procedure the triclosan distills intact, while the triclocarban is hydrolyzed, and the hydrolysis products are distilled and extracted. In addition to describing the apparatus, data are presented on the completeness of the extraction procedure and recoveries from fortified blood samples. Final measurements of the bacteriostats are accomplished by electron capture gas chromatography following appropriate derivative formation to enhance detection sensitivity.