When the frenzied and irregular foodrecruitment dances of bumblebees were first discovered, it was thought that they might represent an evolutionary prototype to the honeybee waggle dance. It later emerged that the primary function of the bumblebee dance was the distribution of an alerting pheromone. Here, we identify the chemical compounds of the bumblebee recruitment pheromone and their behaviour effects. The presence of two monoterpenes and one sesquiterpene (eucalyptol, ocimene and farnesol) in the nest airspace and in the tergal glands increases strongly during foraging. Of these, eucalyptol has the strongest recruitment effect when a bee nest is experimentally exposed to it. Since honeybees use terpenes for marking food sources rather than recruiting foragers inside the nest, this suggests independent evolutionary roots of food recruitment in these two groups of bees.

A multiresidue method for determining more than 70 pesticides in air has been validated using a single injection with gas chromatography/tandem mass spectrometry (GC/MS/MS). The method validation considered both stages of sampling and analysis. The sampling method, based on active sampling using sorption in sorbent cartidges, was validated by generating standard atmospheres. Performance parameters of the method were evaluated, with a reduction in the limits of quantification by injecting a higher volume of sample extract, and increase of selectivity by the use of MS/MS detection mode. The method was based on solid-phase extraction, which permits a degree of automation. The best adsorbents were found to be Chromosorb 106 and Tenax TA. The retention capacity of these sampling sorbents allows up to 1440 L of air to be sampled without any breakthrough for most of the compounds. Data were generated for assessing the potential exposure of bystanders. The application of the method to the analysis of the air in urban locations near agricultural areas showed that pesticides were present in most of the samples.

An analytical method has been applied to determine volatile organic compounds in zucchini flowers. In a first step, the analytical method was applied to characterize the main scents emitted by whole male and female living flowers of three main commercial cultivars of zucchini (Tosca, Chapin, and Consul). In a second step, the compounds were quantified in different parts of the living flowers to identify the contribution of nectar, petals, anther, and stigma to the aroma profile of the flower. The analytical method is based on headspace solid-phase microextraction coupled on-line with GC and tandem MS detection (HS-SPME-GC-MS/MS). A reference compound is added to samples as part of the field quality control procedure to check for likely analyte losses or sample decomposition. The reference compound also acts as an internal standard for quantification purposes. Results have been statistically studied applying principal component analysis (PCA), which shows that three components explain more than 91% of the variance. PCA emphasizes the great importance of nectar as being the main source of 1,4-dimethoxybenzene and 1,2,4-trimethoxybenzene, which influence the aroma profile of flowers. The remaining components can be accounted for by emissions from petals and sexual organs (adroecium and gynoecium anthers or stigmas).

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