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Morphine and 6-acetylmorphine have been measured in the head hair and pubic hair of heroin users by researchers in the UK to try and establish ranges that indicate the level of drug use. Their data throw doubt on a recommendation that the ratio of morphine to 6-acetylmorphine can be used to confirm heroin ingestion.

The effects of different production steps on the profile of volatile compounds in the Brazilian spirit cachaça have been studied by 2D GC. A double distillation step led to a very different profile compared with single distillation, with potential consequences for beverage quality.

Pyrolysis-gas chromatography/mass spectrometry has been used to identify the chemical markers in natural resins used for violoin varnishes, namely colophony, sandarac, manila copal, elemi, amber and benzoin.

The transfer of an ink component from paper-based milk cartons into the milk has been measured by a GC/MS technique with relatively simple sample preparation. The data revealed that the fat content does not affect the contamination.

Simple aromatic amines that find their way from industrial facilities into local waters can be detected and measured in the field at ppm levels using a portable GC following a quick and simple derivatisation reaction.

Read the official report from the 2nd Annual International Conference on Supercritical Fluid Chromatography, which was recently held in Zurich, Switzerland. The conference was organised by the Green Chemistry Group, a non-profit organization dedicated to the advancement of environmentally sustainable chemical research and development throughout the world.

A comprehensive 2-D GC instrument equipped with a flow-switching modulator was used to determine the concentration of ethanol and eight other alcohols in a retail pump sample of E85 fuel.

The effects of steaming, roasting and oil extraction on the levels of the gamma-irradiation-induced hydrocarbons and alkylcyclobutanones in sesame seeds have been determined by GC/MS, in case food processing interferes with their role as irradiation markers.

The malodorous and corrosive alkylmercaptans that are found in natural gas have been determined by two-dimensional GC using a capillary flow technology device for flow switching between the two columns. The improved performance permits non-selective detection, facilitating field deployment.

Two new procedures for measuring the ethanol carbon isotope ratio in wine, using high-performance liquid chromatography and gas chromatography isotope ratio mass spectrometry, have been developed to improve isotopic methods dedicated to the study of wine authenticity.

Chlorinated pesticides which are classified as persistent organic pollutants have been discovered in the colostrum of 33% of tested Chinese mothers who were in preterm labour. The GC-ECD technique employed is simple, fast and reliable and will help to establish the effects of these chemicals on premature delivery.

The complex compositions of different types of biodiesel fuels have been unravelled by 2D gas chromatography which separated the fatty acid methyl esters on the basis of boiling point followed by polarity. The method allows fuels of different origins to be distinguished from each other.

The definition, determination and uses of GC linear retention indices are reviewed, with special reference to the flavour and fragrance field.

Several different classes of plasticizers have been detected in plastic films intended for food packaging by adapting a published GC method for analysing phthalates in plastic toys. Simulated studies revealed that these compounds migrate into food but the rate is independent of the contact time.

The unpleasant odour emitted by car air conditioning systems has been evaluated by Asian scientists in a specially designed model system using gas chromatography and a series of detectors, including trained human sniffers. Alcohols, aldehydes and carboxylic acids were detected.

The false positive determination of benzene during the headspace GC/MS analysis in vitamin C drinks, has been demonstrated. It is formed during high-temperature incubation and is prevented by lowering the headspace vial temperature to 40°C.

The nails of newborn babies can be used to monitor maternal drug use during pregnancy, say Italian scientists. The main obstacle they foresee is the reluctance of parents to collect clippings over the three-month period that are needed to reflect foetal life.

An optical fibre detector has been developed by Portuguese scientists for the measurement of simple alcohols in industrial atmospheres following GC separation. It gives the same sensitivity as GC-FID, providing an inexpensive alternative that is amenable to miniaturisation.

A simple GC method based on silylation coupled with the use of a medium polar column was developed to separate the different classes of fatty compounds in soapstock and deodorizer distillates derived from the vegetable oil refining process.

The geographical origins of cocaine seizures can be distinguished by analysing their residual solvents using headspace gas chromatography, say French researchers, who have optimised the procedure using a fractional factorial design.