The current immunoassay screening methodologies used to detect sympathomimetic amines within the context of workplace drug testing may fail to detect a number of the emerging designer drugs, for example β-keto amphetamines and piperazine derivatives, commonly referred to as 'legal highs'. Therefore, a rapid multi-analyte qualitative screening method, using ultra-high-pressure liquid chromatography-tandem mass spectrometry (LC-MS/MS), was investigated for analysis of new designer drugs that have emerged from the former legal highs market. Eight analytes were targeted as model compounds: 4-methylmethcathinone (mephedrone), 3,4-methylenedioxymethcathinone (bk-MDMA, 'methylone'), 2-methylamino-1-(3,4-methylenedioxyphenyl)butan-1-one (bk-MBDB, 'butylone'), 4-methoxymethcathinone (bk-PMMA, 'methedrone'), 1-benzylpiperazine (BZP), 1-(3-trifluoromethyl phenyl)-piperazine (TFMPP), 1-(3-chloro phenyl)-piperazine (mCPP), and 3, 4-methylenedioxypyrovalerone (MDPV). The LC-MS/MS method developed encompassed direct analysis following a 1:4 dilution of urine with mobile phase to reduce matrix effects. Although not all compounds were completely resolved chromatographically, two product ions conferred sufficient specificity to allow target analyte identification. Although all target analytes were readily detected at 500 ng/ml, a cut-off of 1000 ng/ml was chosen to mirror the amphetamine screening cut-off commonly used for routine analysis of workplace drug testing samples. In conclusion, direct analysis using LC-MS/MS offers an attractive way forward for the development of a rapid routine screen for new psychoactive substances, particularly given the growing number of novel compounds.

Alternatives to highly-volatile ethanol or analytically complex cooking oil were examined as potential fatty-food simulants which would undergo high-temperature exposures to food-packaging polymers in food-packaging evaluation studies. The alternatives consisted of alcohols containing four to eight carbons. As test cases, the migration of Irganox 1010 antioxidant from high-density polyethylene and polypropylene into the higher alcohols was compared to the migration of Irganox 1010 into aqueous ethanol solutions and cooking oil, the US Food and Drug Administration's currently recommended fatty-food simulants. The data obtained showed slightly greater migration of the antioxidant into 95% ethanol than into cooking oil, and slightly less migration into 50% ethanol than into cooking oil. The migration of the antioxidant into the alcohols consisting of four or more carbons was much greater than the migration observed in cooking oil. In many experiments the polymers became depleted of the antioxidant prior to the end of the short, high-temperature exposure period (i.e. 2 h at 250 degrees F) to the higher alcohols. Also, for all experiments run under the same time/temperature/simulant conditions, migration of the antioxidant was greater from polypropylene than from high-density polyethylene. Diffusion coefficients generated for 95% ethanol and corn oil from these data compare closely with data from the literature.

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A comparison was undertaken between two machines that utilise accelerated methods to measure oxidative stability: the Rancimat (Metrohm, Switzerland) and the single channel chemiluminescence instrument (ACL Instruments, Switzerland). The results from the machines showed good correlation for the measurement of the oxidation induction time of corn oil. For the ACL Instrument, the effect of the sample holder material (aluminium or borosilicate glass) was also investigated and clear differences were noted. Finally, a stability study was carried out over a period of 6 months, with corn oil, stored in the dark at three temperatures: ~4, ~27, ~40 °C and it was observed that it was possible to track subtle changes in oxidative stability using chemiluminescence.