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High-resolution chemical records of main and trace ionic components of snow precipitation over the last 250 years were obtained by analysing the first 36 m of a firn core drilled at Talos Dome, a dome located in the ice divide between northern Victoria Land and Oates Land (East Antarctica Pacific Ocean/Ross Sea sector). The concentration/depth profiles of some relevant chemical parameters are discussed on the basis of a previous stratigraphic dating, set up following the seasonal signatures of non-sea-salt (nss) sulphate deposition and synchronised by using tritium and volcanic temporally known horizons. Particular attention is paid to the study of the temporal trends of the sea spray components (Na+, Cl−, Mg2+) and S and N cycle compounds ( ) to understand the main sources, transport mechanisms and depositional processes of these compounds at the deposition site. Good correlations between the sea spray markers show that the primary marine contribution is relevant, though Talos Dome is located at a relati...

Formaldehyde concentrations were determined in over 1800 snow samples (snowpit, firn cores and superficial snow) from Antarctica by a sensitive spectrofluorimetric Flow Injection Analysis method. The method performances (detection limit: 55 ng/L; reproducibility: 2.5% at 1 µg/L level; linear range: 0.1–3000 µg/L) allowed a reliable determination of formaldehyde content in all the collected samples. The range of determined concentrations was 0–70 µg/L with a mean concentration of 7.7 µg/L and a median concentration of 5.8 µg/L. The formaldehyde background level was estimated at a few micrograms per liter in coastal and plateau areas of Northern Victoria Land. In some stations the background values are modulated by HCHO deposition events recurring over relatively large time periods.

A sensitive method for the formaldehyde determination in aqueous samples by Flow Injection Analysis has been developed. Formaldehyde reacts with acetylacetone, acetic acid and ammonium acetate to form diacetyldihydrolutidine, detectable by its fluorescence; the effects of various surfactants upon this spectrofluorimetric method have been assessed. Fluorescence enhancements from 15-70% were observed in comparison with that without surfactant. The developed method has a detection limit of 55 ng/l and a precision of 2.5% at 1 µg/l level. The calibration graph is linear in over the range 0.1-3000 µ/l. The sensitivity, speed, ease of use and small volume of sample make this method ideal for formaldehyde determination in precipitation samples with concentration from very low to very high by continuous or semicontinuous analysis.