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Laboratory bioassays on insecticidal activity of essential oils (EOs) extracted from six Mediterranean plants (Achillea millefolium, Lavandula angustifolia, Helichrysum italicum, Foeniculum vulgare, Myrtus communis, and Rosmarinus officinalis) were carried out against the larvae of the Culicidae mosquito Aedes albopictus. The chemical composition of the six EOs was also investigated. Results from applications showed that all tested oils had insecticidal activity, with differences in mortality rates as a function of both oil and dosage. At the highest dosage (300 ppm), EOs from H. italicum, A. millefolium, and F. vulgare caused higher mortality than the other three oils, with mortality rates ranging from 98.3% to 100%. M. communis EO induced only 36.7% larval mortality at the highest dosage (300 ppm), a similar value to those recorded at the same dosage by using R. officinalis and L. angustifolia (51.7% and 55%, respectively). Identified compounds ranged from 91% to 99%. The analyzed EOs had higher content of monoterpenoids (80-99%) than sesquiterpenes (1-15%), and they can be categorized into three groups on the basis of their composition. Few EOs showed the hydrocarbon sesquiterpenes, and these volatile compounds were generally predominant in comparison with the oxygenated forms, which were detected in lower quantities only in H. italicum (1.80%) and in M. communis (1%).

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A simple and rapid method is reported for the routine determination 1-phenylazo-2-naphthol (Sudan I) in chilli powder and in chilli-containing food products. The method involved Soxtec extraction from the products followed by high-pressure gel permeation chromatographic clean-up collecting the appropriate fraction. Analysis of this fraction was by HPLC with UV/VIS detection. The limit of detection was 7 microg kg(-1) and the limit of quantification was 13 microg kg(-1). The identity of Sudan I in food products was established by electrospray LC/MS with MS/MS confirmation. From a small survey of 30 retail samples, 11 samples of crushed chilli, Italian pasta, chilli-snack and vegetable sauce contained levels of Sudan I ranging from 24 to 5591 microg kg(-1).