Children absorb tris-BP flame retardant from sleepwear: urine contains the mutagenic metabolite, 2,3-dibromopropanol.

The flame retardant, tris(2,3-dibromopropyl)phosphate (tris-BP), which is a mutagen and causes cancer and sterility in animals is absorbed from fabric by people. 2,3-Dibromopropanol, a metboloite of tris-BP and a mutagen itself, has been found in the urine samples of ten children who were wearing or who had worn tris-BP-treated sleepwear. Eight of these children were wearing well-washed sleepwear and the possibility of absorption of tris-BP from well-washed sleepwear discussed. 2,3-Dibromopropanol was not found in the urines of one child and one adult who had never worn tris-BP-treated garments.

Metabolism of diethylstilbestrol in the C3H mouse: chromatographic systems for the quantitative analysis of DES metabolic products.

Initial excretion studies with orally administered [monoethyl-1-3H] DES demonstrated the feces to be the principal mode of elimination of DES in the C3H mouse. Metabolic studies with tritiated DES and/or [UL-14C] DES were performed with orally dosed C3H high (MTV+) and low (MTV-) titer MMTV female mice. Extraction and partitioning of the fecal radioactivity demonstrated 77 to 86% (n = 4) to be benzene soluble and the remainder H2O soluble. The principal product in the organic phase following Sephadex LH-20 and HPLC purification was DES. The aqueous phase was resolved by LH-20 into two conjugate fractions that were partially hydrolyzed by beta-glucuronidase. The principal aglycone was chromatographically identical with authentic DES. The urinary conjugates were resolved into six fractions. The four major fractions were 80% hydrolyzable with beta-glucuronidase. Two of these fractions had trans-DES as the principal aglycone, whereas the other two had a major peak similar to but not chromatographically coincident with cis-DES. In certain experiments mice were sequentially dosed with tritium (24 hr) followed by a 14C dose (24 hr). Two mice (MTV+) were also previously fed 1000 ppb DES prior to these experiments. The tritated and 14C products were combined and analyzed simultaneously. This experiment did not reveal significant differences in the metabolism due to the modes of radioactive labeling, MMTV titer, or the prior feeding of DES. The developed methodology was judged to purify quantitatively 90% or more of the DES radioactive products.

Characterization of sterols by gas chromatography-mass spectrometry of the trimethylsilyl ethers.

The utility of combined gas chromatography-mass spectrometry in the analysis and characterization of sterols has been explored. Methylene unit (MU) values and principal mass spectrometric data are presented for trimethylsilyl ethers of 28 sterols, including the major natural sterols. The diagnostic value of the fragmentation of trimethylsilyl ethers of Delta(5)-3 beta-hydroxysteroids has been confirmed. Characteristic fragmentations of Delta(4)-3 beta-trimethylsilyloxysteroids, and of Delta(5,7)-3 beta-trimethylsilyloxysteroids were also found. Location of side-chain hydroxyl groups is facilitated by the alpha-cleavages typical of the trimethylsilyl ethers. Fragmentations of saturated sterols, and of Delta(7), Delta(8(9)) and Delta((14)) stenols, are less influenced by trimethylsilyl ether formation, but the derivatives still afford satisfactory mass spectra. The combination of gas chromatographic and mass spectrometric information allows positive identification of any of the sterols examined, whereas application of either technique alone may give inconclusive results.

High-resolution biomedical gas chromatography. Determination of human urinary steroid metabolites using glass open tubular capillary columns.

Recently developed analytical procedures for the qualitative and quantitative analysis of human urine for major and minor steroid metabolites are described. Steroid profile samples were obtained by enzymic hydrolysis with beta-glucuronidase and sulfatase. Methoxime-trimethylsilyl ether derivatives of steroid metabolites were prepared; the recommended procedure converts all ketone groups (except the 11-one group) into methoxime groups and all hydroxyl groups into trimethylsily ether groups. These derivatives are thermally stable, readily volatilized, not subject to dehydration or adsorption on gas chromatographic columns, and suitable for both quanlitative and quantitative analytical studies. Thermostable glass open tubular capillary columns, coated with the non-polar phase SE-30, and containing dispersed particles of silanized silicic acid, were used for the gas chromatographic separation. Illustrations of profiles for normal female and male subjects, and patients with a testosterone-secreting ovarian tumor, congenital adrenal insufficiency and a dehydroepiandrosterone-secreting adrenal tumor are included.

Concurrent determination of alpha-tocopherol and free fatty acids in human plasma by glass open tubular capillary column gas chromatography.

A new gas chromatographic procedure was developed for the concurrent analysis of mixtures of long-chain acids (as methyl esters), cholesterol (as the trimethylsilyl ether) and the tocopherols (as trimethylsilyl ethers). This method was used in a study of free fatty acids and alpha-tocopherol in the plasma of normal subjects and stroke patients. The chromatographic separation was based upon the use of thermostable glass open tubular capillary columns prepared with Silanox (procedure of Lin, Pfaffenberger and Horning) and a new polar liquid phase (Schwartz-Mathews polyphenyl ether sulfone phase). The German-Horning injection system was used in a modified gas chromatograph.