Exploring Sustainable Remediation Options: The Mycodegradation of Halogenated Nitroaromatic Compounds by Caldariomyces fumago

Chlorinated and fluorinated nitrophenols (HNCs) are widely used in agriculture and industry, with a global market valued at USD $25 billion, one which is expected to grow by 5% by 2030. However, these compounds pose significant environmental risks; they are classified as toxic by the International Agency for Research on Cancer (IARC). Existing treatment methods include advanced oxidation, adsorption, and bioremediation, though to date, there has been only limited research on fungal remediation of these halogenated pollutants. This study aims to explore a sustainable approach by using fungi’s potential to degrade HNCs in minimal media. Ten fungi were selected through literature screening; Caldariomyces fumago and Curvularia sp. were highly effective, degrading over 50% of 2-chloro-4-nitrophenol (2C4NP) and 80% of 5-fluoro-2-nitrophenol (5F2NP) within 24 and 48 h, respectively. Additionally, five strains showed degradation potential for fluorinated compounds. Further studies revealed C. fumago could degrade up to 1 mM of chlorinated compounds and 12 mM of fluorinated compounds, far exceeding any known environmental concentrations of HNCs; importantly, ecotoxicology tests demonstrated reductions in toxicity of 77% and 85%, respectively. This work highlights fungi’s underexplored ability to degrade toxic HNCs, offering a sustainable mycoremediation strategy and positioning mycology as a critical tool for future environmental remediation efforts.