Fungal diversity in lake and sea beaches of Italy: Relevance to human health

Fungal diseases correlated to beach sand or water have not yet been demonstrated due to the lack of epidemiological studies. This study aims to illustrate the fungal population in beach sands of the two largest Italian lakes and in sands and waters of Mediterranean coasts of Southern Italy to contribute to the identification and assessment of causes of microbiological pollution that might impair bathers health. A great difference was observed between the two lakes, where the total of colony-forming units (CFU) ranged from 33.3 to 1049.9 CFU/g. For coastal sands, the total CFU ranged from 216.7 to 538.8 CFU/g, and for coastal waters the total ranged from 185 to 368.7 CFU/ml. The survey revealed the prevalence of opportunistic pathogenic moulds, mainly Aspergillus spp. (A. niger and A. fumigatus) and Penicillium spp., both in freshwater and costal bathing sites. Dermatophytes and yeasts were not detected in the freshwater sands while they were found at low load in coastal waters (3.3 CFU/ml) and sands (1.7 CFU/g). Differences were observed between urban and non-urban coastal beaches with regard to isolation of dermatophytes only from one urban beach. The present study reports a great diversity of fungi in sand and water of bathing beaches confirming that the Mediterranean region has a greater variety of fungal species.

Highlights: Few studies have been conducted on fungal pathologies due to exposure to sand or beach water; Beach sand and recreational water should be monitored for fungi; Differences were observed between urban and non-urban Italian coastal beaches and between lakes; Dermatophytes and yeasts were not detected in freshwater sands.