Open Access

Subsociality and wood-eating or xylophagy are understood as key drivers in the evolution of eusociality in Blattodea (cockroaches and termites), two features observed in the cockroach genus Cryptocercus, the sister group of all termites. We analyze two high-quality genomes from this genus, C. punctulatus from North America and C. meridianus from Southeast Asia, to explore the evolutionary transitions to xylophagy and subsociality within Blattodea. Our analyses reveal evidence of relaxed selection in both Cryptocercus and termites, indicating that a reduction in effective population size may have occurred in their subsocial ancestors. These findings challenge the expected positive correlation between dN/dS ratios and social complexity, as Cryptocercus exhibits elevated dN/dS values that may exceed those of eusocial termites. Additionally, we infer a reduction in the number of Ionotropic Receptors and a change from uni- to bimodal methylation signatures in protein coding genes in a common ancestor of Cryptocercus and termites, mechanisms previously thought to have evolved with the emergence of eusociality in termites. Future studies incorporating additional genomic data from diverse blattodean species can further build on these findings and provide deeper insights into the molecular mechanisms driving transitions to xylophagy and eusociality.

Rapid detection and localization of liquid fuel spills is critical for first responders assessing fire and health hazards, yet current methods require ground-based sampling or specialized instrumentation, limiting their practicality for wide-area emergency response. We present a drone-based passive colorimetric sensor system using test strips impregnated with Nile red, similar to colored confetti. Nile red is a solvatochromic dye that undergoes distinct visible color transitions upon exposure to different liquids. The dye is embedded within a polymer matrix that minimizes leaching while providing high optical contrast between dry, water-exposed, and fuel-exposed states. The sensor strips exhibit solvent-specific colorimetric responses within one minute of exposure, readily detectable by standard RGB cameras mounted on unmanned aerial vehicles (UAVs) at altitudes up to 50 m. Automated classification was validated at 20 m altitude, enabling remote surveillance of contaminated surfaces without specialized equipment. Color-corrected image analysis using Calibrite ColorChecker calibration ensures reliable interpretation under variable field illumination (625–77,000 lux). Systematic laboratory evaluation of twelve fossil and bio-derived fuels revealed characteristic hue shifts that clearly discriminate ethanol-containing gasoline blends from diesel-range fuels. Rather than identifying specific molecules, the method functionally categorizes contamination into gasoline/ethanol blends versus diesel-type fuels, reflecting bulk polarity rather than molecular composition. Field validation confirmed localization and classification of fuel-exposed sensors, achieving F1 scores of 0.94 for gasoline and 0.98 for diesel detection with no false positives in the tested scenarios. This cost-effective and scalable approach provides actionable information on both contamination location and fuel type, crucial for rapid hazard assessment in emergency response scenarios.

Incineration is currently the only commercial full-scale technology available to destroy per- and polyfluoroalkyl substances (PFAS) in large solid and liquid waste streams. Given previous experience of dioxin formation during halogenated waste incineration, concerns about the emission of products of incomplete destruction (PIDs) from PFAS incineration exist. The overarching objective of this project is to track the fate of fluorine during full-scale hazardous waste incineration in order to demonstrate the readiness, viability, and level of safety for thermal PFAS destruction in various waste streams. The specific objectives of this project are to enhance our understanding of key variables and conditions on PFAS incineration performance, to identify major PIDs under insufficient treatment conditions, to explore the catalytic role of fly ash and other process-relevant surfaces in thermal PFAS decomposition, and to determine the potential formation of polyfluorinated dibenzodioxins and dibenzofurans

The analysis of paper-based food contact materials (FCM) has gained increasing attention due to the widespread use of per- and polyfluoroalkyl substances (PFAS) and their known toxic effects and environmental persistence. As regulatory frameworks for PFAS in FCM remain limited, sensitive and reliable analytical methods are necessary to ensure food safety. While PFAS analysis is predominantly performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), a systematic development of gas chromatography coupled to mass spectrometry (GC-MS)-based methods for multiple PFAS classes remains limited. In this study, two pre-column derivatization techniques were optimized and evaluated for GC-MS determination of perfluoroalkyl carboxylic acids (PFCA), fluorotelomer alcohols (FTOH), and fluorotelomer carboxylic acids (FTCA). Both derivatization methods enabled qualification and quantification of the targeted PFAS with comparable limits of detection in the low ng/mL range. N,N-Dimethylformamide dimethyl acetal (DMFDMA) derivatization proved to be more sensitive with a limit of detection down to 0.85 ng/mL. In addition, this derivatization approach was successfully automated within the GC-MS workflow, resulting in sample preparation times comparable to those of LC-MS-based methods. The application of this optimized method to paper-based FCM demonstrated its suitability for real world FCM analysis. Results of PFAS content per targeted PFAS of 26.6 to 261.4 ng/g highlight the potential of GC-MS analysis, particularly when combined with automated derivatization, as a viable alternative or complement to LC-MS for PFAS analysis in FCM.

In this work, the first systematic study evaluating microwave-assisted extraction (MAE) as a sample-preparation method for extractable organic fluorine (EOF) in soil samples, using modified polytetrafluoroethylene (PTFE-TFM) vessels was conducted. EOF is increasingly used as a sum parameter to estimate PFAS contamination in environmental matrices (mostly surface waters and more recently in soils). EOF was determined in a soil sample using high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). Key MAE parameters, such as temperature, heating time, and extraction-solution composition were optimized. The possible leaching of fluoropolymers and thus, the increase in blank values in PTFE-TFM vessels was evaluated. The proposed MAE method was compared to an ultrasound-assisted extraction (UAE) method to evaluate the EOF extraction efficiency from a soil sample. The use of 0.5% acetic acid in methanol as the extracting solution in MAE influenced both EOF extraction and blank levels. By using quartz inserts inside PTFE-TFM vessels this problem was minimized. Under the conditions of 1 g of soil sample, 20 mL of 0.5% (v/v) acetic acid in methanol, a heating program of 5 min up to 80 °C and 15 min hold at 80 °C by MAE, the agreement between the proposed MAE and UAE method was 98 ± 6% for EOF extraction. Furthermore, the method presented an outstanding selectivity of EOF extraction even in the presence of fluoride in soil samples (up to 50 µg g−1). Therefore, the proposed method represents a new pathway in sample preparation that is superior in the extraction efficiency of EOF from soil samples compared to UAE methods.