Seasonal occurrence of Alternaria (1993- 2004) and Epicoccum (1994-2004) spores in Trieste (NE Italy).

Fungal spores are known to trigger allergic respiratory diseases. Very little is known about airborne fungal spore presence in Trieste. This paper reports the seasonal (June-October) Alternaria (1993-2004) and Epicoccum (1994-2004) spore concentrations during these years, using a Hirst sampler. Daily spore counts fluctuate considerably from one day to the next. Airborne spores of Alternaria and Epicoccum tend to display a similar temporal pattern, with the peak daily count occurring in late summer - early autumn; a shifted occurrence towards the early autumn of the maximum peaking day of Epicoccum was observed, compared to Alternaria, on average. A great variability in seasonal spore concentrations was also found throughout the years. Seasonal totals of 6,076 Alternaria spores and 2,796 Epicoccum spores were found over the examined years, on average. 2003 was an exceptionally high year for Alternaria with a seasonal total of 15,021 spores. Statistical analyses comparing daily spore counts with meteorological parameters were carried out. Weather variables have been shown to affect the spore concentrations in the air. Alternaria and Epicoccum respond in a similar way to meteorological factors. Daily spore levels showed a significant positive correlation with temperatures; weak significant negative correlations have been found with the other parameters.