Congo Red is a complex aromatic azo dye whose metabolites can be toxic due to their carcinogenicity, mutagenicity, and various associated toxic effects on flora, fauna, and humans. Different technologies have been employed to degrade this dye, including biodegradation, radiation-based degradation, and chemical degradation with catalysts and photocatalysis. Among these, the use of TiO₂-based materials combined with photocatalysis has proven to be an effective technology for its degradation. However, the wide bandgap of TiO₂ limits its efficiency under visible light, prompting the need for modifications such as doping with metals, metalloids, and organic compounds. These modifications enhance its photocatalytic performance under visible light, achieving degradation efficiencies of up to 100% under optimal conditions. This article explores recent advances (from 2020 to the present) in the degradation of Congo Red using TiO₂-based photocatalysts under visible light, focusing on their characteristics, synthesis methods, and degradation efficiencies. Additionally, it compares the TiO₂-based photocatalysis with visible light to other available technologies, emphasizing its potential as a sustainable and efficient approach while addressing the importance of monitoring degradation byproducts to prevent the generation of equally or more toxic compounds.

This study examines the significant impact of bacterial, algal, and fungal toxins on foodborne illnesses, and stresses the importance of advanced detection techniques, such as high-performance liquid chromatography (HPLC)-based methodologies. It emphasizes the urgent need for further advancements in these techniques to ensure food safety, as they offer significant benefits, including low detection limits and the ability to be combined with other techniques to detect a wide range of toxins. In this regard, HPLC has emerged as a versatile and sensitive analytical technique for this purpose. Various HPLC methods, often enhanced with detectors such as ultraviolet (UV), fluorescence (FD), and mass spectrometry (MS), have been developed to identify and quantify microbial toxins in a wide variety of food samples. Recent advancements include HPLC-FD methods that utilize the natural fluorescence of certain aflatoxins, improving detection sensitivity. HPLC-MS/MS and UHPLC-MS/MS techniques offer high selectivity and sensitivity, making them suitable for detecting a wide range of toxins in trace quantities. The adaptability of HPLC, combined with innovative detection technologies and sample preparation methods, holds significant potential for enhancing food safety monitoring and reducing the global burden of foodborne diseases.

Aflatoxins (AF) are highly toxic secondary metabolites produced by various species of Aspergillus, posing significant health risks to humans and animals. The four most prominent types are aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), and aflatoxin G2 (AFG2). These mycotoxins are prevalent in various environments, including water sources and food products. Among these mycotoxins, AFB1 is recognized as the most toxic, mutagenic, and carcinogenic to humans. Consequently, most efforts to mitigate the impact of AF have been focused on AFB1, with photocatalysis emerging as a promising solution. Recent research has demonstrated that using semiconductor photocatalysis, particularly titanium dioxide (TiO₂), combined with UV–visible irradiation significantly enhances the efficiency of AF degradation. TiO₂ is noted for its high activity under UV irradiation, non-toxicity, and excellent long-term stability, making it a favorable choice for photocatalytic applications. Furthermore, TiO₂ combined with visible light has demonstrated the ability to reduce AF contamination in food products. This article summarizes the working conditions and degradation rates achieved, as well as the advantages, limitations, and areas of opportunity of these methodologies for the degradation of AF and preventing their production, thereby enhancing food and water safety.