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The aim of this work is to determine the content of essential and toxic elements in 25 raw propolis samples, when considering pollution agents and geographical and botanical factors. The microwave-assisted digestion was the most reliable and accurate method for determination of inorganic elements in propolis samples. The results were obtained using certified reference materials in a good agreement with certified values. Inductively coupled plasma atomic emission spectroscopy was used for the determination of 23 macro- and microelements (Ag, Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Sb, Se, Si, Sn, and Zn). A Mercury analyzer was also utilized for the detection of the total Hg. Among the analyzed metals, Ca, K, Mg, Zn, Si, S, Fe, Al, P, and Na were found to be the most predominant. Heavy metals (As, Cd, Hg, and Pb) were determined in minimal concentration, and Pb was the highest mean contained toxic (<3.80 mg/kg), without influence on provisional tolerable weekly intake values. The method can be applied for routine analysis and quality and environmental pollution controls of toxic elements in propolis samples. The results obtained indicate no pollution of the collection areas and naturally high concentration of Al (460 ± 62.2 mg/kg).

The present investigation constitutes the first comprehensive report on the phenolics identified in southern Spanish propolis. The results revealed that the samples tested showed a high scavenging activity and therefore indicate the possible use of Andalusian propolis as an important source of natural anti-oxidants.

Summary — Twenty-nine hives infested by Varroa jacobsoni were sampled over a 2-year period in order to find out their degree of infection by Nosema apis. The hives were situated in ten apiaries distributed throughout southern Spain. N apis has been found in 90% of the apiaries sampled and in 55.17% of the hives studied, but only 5.1% of the bees were infected. We have found a low correlation between the average number of spores per infected bee in the positive samples and the percentage of infected bees (r 2 = 0.2438; P < 0.001; n = 33), and between the average number spores in the composite samples of 60 bees and the percentage of infected bees (r 2 = 0.4557; P < 0.001, n = 33).Our results show that N apis and V jacobsoni could develop independently and that those samples which manifested a low, medium and high infestation by V jacobsoni had percentage infections with N apis of 22.6% ± 3.6% vs 47.5% ± 16.2% vs 16.7% ± 10.4% respectively, without significant differences (F = 0.2817; P = 0.7567). A progressive increase in the number of spores per individual was detected with increasing levels of

—Two hundred and two samples of bees from 35 beehives distributed among 12 apiaries were analysed. They were collected between October 1990 and October 1992 in southern Spain. The thoraxes of 25 bees taken from each sample were examined individually (5 050 in total) to look for diptera larvae (myiasis). Twenty-four fly larvae were discovered in the anterior dorsal part of the bees' thoraxes. The flies were widely distributed throughout southern Spain although honeybee infestations reached a low rate of incidence (0.48%), mainly in July.