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A high-resolution mass spectrometric selected ion monitoring (HRMS-SIM) methodology for the analysis of all tetra-through octachlorinated dibenzo-p-dioxins (Cl/sub x/DD, x = 4-8) and dibenzofurans (Cl/sub x/DF, x = 4-8) utilizing an alternative lockmass system has been developed at the Ministry of the Environment (MOE). Incorporation of the MOE lockmass system gives an enhancement in sensitivity, easier control of the lockmass concentration in the ion source, and greater resolution between the lockmass and the sample ion signals than dose the conventional perfluorokerosene (PFK) lockmass system. In addition, the method can be adapted to any sector instrument having a similar lockmass facility and to any HRMS-SIM analysis with the appropriate choice of reference standards. A comparison of the MOE and PFK systems is reported.

The study of an environmental sample using a variety of mass spectral techniques, in order to identify as many components as possible, indicates the presence of a number of novel chlorinated compounds. These compounds are characterised by mass spectrometry and 360 mHz 1H NMR and their synthetic route is proposed.

14 C-Tetrahydrocannabinol (THC) was injected i.v. into a total of 92 adult Wistar rats. At 14 times ranging from 2 min to 48 hr afterwards, groups of animals were examined for total 14 C activity and thin-layer chromatographic (TLC) pattern of 14 C distribution in blood, brain, heart, kidney, liver, lung, muscle, spleen and perirenal fat. The time course of rise and fall of radioactivity in the various organs and tissues closely resembled that of thiopental and other strongly lipophilic substances. Relatively high levels persisted in fat 48 hr, but levels in brain were quite low. TLC analysis showed the early appearance of 7-hydroxy-THC in all tissues, followed by increasing amounts of more polar compounds and disappearance of THC, except in fat. Levels were much lower after i.p. injection, and whole body autoradiography showed most of the activity remaining in the peritoneal cavity.

The acid fraction from an extract of a test well sample obtained from a landfill site has been examined by capillary gas chromatography mass spectrometry, and liquid chromatography mass spectrometry. In the latter case conventional and glass-lined stainless steel microbore liquid chromatography columns were used. Desorption chemical ionization and field desorption mass spectrometry have been used to profile the major components present in the mixture. This combined approach enables a more detailed characterization of the sample to be obtained and the techniques have been found to be mutually complementary. Glass-lined stainless steel microbore columns used with a gradient system are shown to provide high quality liquid chromatographic mass spectrometric data.

The effects on the house fly, Musca domestica (L.), of a series of cis-9 alkenes containing 19–25 carbon atoms were investigated. An unexpectedly wide spectrum of these homologous hydrocarbons showed biological activity. Synergism and interesting changes in behavioural responses (excitement, mating, and orientation) varying with structure and concentration were observed.

Recent developments in the coupling of a liquid chromatograph with a mass spectrometer are reviewed with particular emphasis on commercially available systems. A new interface of the moving belt type enables molecular weight to be obtained by electron impact or chemical ionization from a wider range of compounds than was previously possible with interfaces of this type. Use of fast atom bombardment mass spectrometry with a moving belt interfaces shows promise for further extension of the compounds amenable to LC/MS study. Improvements in the methods of feeding the sample onto the belt, by use of a nebulizer or microbore liquid chromatography have resulted in improved. sample detection limits and easier handling of mobile phases with a high water content. The range of compounds amenable to study by interfaces of the direct liquid introduction type have also been extended. Thermospray ionization systems show considerable potential for handling more difficult molecules and in providing improved detection limits. Advances in the use of atmospheric pressure ionization in this area are also described. Finally the utility of LC/MS in the environmental area is reviewed and analysis of testwell samples from a landfill site using the technique is described.

In the inverse Diels–Alder reactions of mono-substituted s-tetrazines, 3-p-tolyltetrazine and phenyl-acetylene gave 3,4-diphenylpyridazine, while the same tetrazine and methylacetylene gave the 3,5-disubstituted product.