The relationship between metal levels in the Olt River ecosystem in southern Romania (measured during 2018‒2019, with 1064 sediment and water samples) and daily climate data were explored to assess the need for targeted source identification and mitigation strategies. In 2018, there was a strong relationship between the sediment Pb, As, Cd, and Hg contents and temperature (r > 0.8, p < 0.001). Mercury in sediments had a positive correlation with precipitation, and Hg in the water correlated with minimum temperature in May 2018 (p < 0.01). In July 2019, heavy metals were positively correlated with precipitation and negatively correlated with temperature. According to nonsymmetrical correspondence analysis, the four climate parameters analyzed were linearly correlated with the frequency of metal detection (p < 0.001) in both years. The statistical analysis showed strong relationships between heavy metal levels and climatic factors and attributed the discrepancies in elemental concentrations between 2018 and 2019 to climate warming.
The increasing use of engineered nanoparticles (NPs) in consumer and biomedical products has raised concern over their potential accumulation, transformation, and toxicity in biological systems. Accurate analytical methods are essential to detect, characterize, and quantify NPs in complex biological matrices. Inductively coupled plasma mass spectrometry (ICP‐MS) has emerged as a leading technique due to its high sensitivity, elemental selectivity, and quantitative capabilities. This review critically evaluates recent advances (from January 2020 onward) in ICP‐MS‐based methods for analysis of NPs in biological samples. Two main strategies are discussed: single‐particle ICP‐MS (spICP‐MS) and hyphenated techniques coupled to ICP‐MS. spICP‐MS allows direct determination of particle size, concentration, and metal content at environmentally relevant levels. It is the most widely used approach and is therefore examined in greater detail, with attention to extraction procedures, particle types, sample matrices, and inherent limitations. Advances in laser ablation spICP‐MS for tissue imaging and spatially resolved NPs detection are also covered. Methods using hyphenated techniques, such as hydrodynamic chromatography, size‐exclusion chromatography, capillary electrophoresis, Taylor dispersion analysis, and field‐flow fractionation, are increasingly employed to address limitations spICP‐MS. These approaches can provide enhanced insight into particle size distributions, aggregation behavior, and interactions with complex sample matrices. This review offers a comparative evaluation of both single‐particle and hyphenated methods, discussing their respective advantages and limitations. Emphasis is placed on the complementarity of these techniques and how their combined use can offer a more complete understanding of NPs’ fate in biological systems.
A virus-free (VF) A. fumigatus isolate has been shown to be resistant in competition with Pseudomonas as compared to the isogenic line infected with Aspergillus fumigatus polymycovirus 1 (AfuPmV-1), and this phenotype was apparently related to alterations in iron metabolism. Here we investigated further the mechanisms underpinning this phenotype. The extracellular siderophore profiles of five isogenic VF and virus-infected (VI) strains were sampled at 24, 31, 48, 54, and 72 h in submerged cultures and quantitatively examined by liquid chromatography and mass spectrometry. Intracellular profiles of conidia and cultures at the stationary growth phase were defined. VF A. fumigatus demonstrated the best fitness represented by the fastest onset of its exponential growth when grown on an iron-limited mineral medium. The exponential phase and transitional production phase of the extracellular triacetylfusarinine C (TafC) were achieved at 24 and 31 h, respectively, contrary to VI strains, which acted more slowly. As a result, the TafC reservoir was consumed sooner in the VF strain. Additionally, the VF strain had lower ferricrocin and higher hydroxyferricrocin content in the pellet during the stationary phase. All of these differences were significant (Kruskal–Wallis, p < 0.01). In our study, the siderophore reservoir of a VF strain was consumed sooner, improving the fitness of the VF strain in competition with P. aeruginosa.