Fungal Contamination in Thermal Springs: A Comparative Study Between Pool Water and Air Samples

Abstract

Thermal springs have been used for therapeutic purposes in Türkiye for centuries and remain popular for both health-related treatments and recreational activities. However, the increasing use of thermal pools without strict hygiene measures has been associated with rising incidences of infections such as folliculitis, dermatitis, otitis, conjunctivitis, and respiratory, genitourinary, and gastrointestinal infections. In this study, 24 water and air samples from eight indoor spa pools were examined, yielding 205 fungal isolates. Microfungal counts ranged from 5 to 1,228 cfu/m³ in air and 2,000 to 228,000 cfu/m³ in water. The isolates belonged to genera including Aspergillus, Penicillium, Alternaria, Paecilomyces, Mucor, Rhizopus, Fusarium, Pythium, and others. The fungal community was dominated by Penicillium (35%) and Aspergillus (29%). Among the 69 Aspergillus isolates, medically important species such as A. fumigatus, A. terreus, A. niger, and A. flavus were detected. These findings demonstrate that thermal pools may serve as reservoirs for opportunistic fungi, underscoring the need for molecular surveys and stricter monitoring to minimize public health risks.

Keywords

• Aspergillus
• thermal waters
• indoor air
• airborne microfungi

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