Frederic Coulon

Real-time insight into the characteristics of bioaerosol emissions is crucial to better understand the potential risks and to develop effective solutions to manage bioaerosol emissions from biowaste management and other industrial sources.

The behaviour of chemical warfare agents (CWAs) on urban materials significantly impacts forensic and military responses to chemical incidents. This study examines the persistence of two CWA simulants for blister and nerve agents, methyl salicylate and benzyl salicylate, at two temperatures (8 and 18°C) over the course of one month on two commonly used building materials in the United Kingdom (UK). A novel aspect of the work is the kinetic comparison of contaminant behaviour on highly fragmented, UK-relevant construction materials, representing conditions that may arise following explosive dissemination. Half-lives and activation energies (Ea) for the composite process of CWA dissipation, which includes evaporation, diffusion and degradation, were calculated under various conditions. Results showed that matrix properties and external temperature strongly influenced dissipation rates, with fibre cement board promoting simulant retention compared with brick. Methyl salicylate, a simulant for HD, displayed a half-life of 3.2 to 3.7 days in brick at two temperatures. Comparatively, benzyl salicylate, a simulant for A-series agents, was found to be much more persistent, with half-lives of 144 and 289 days in brick. Caution should be exercised when interpreting the half-lives given the one-month experimental duration and limited overlap with kinetic models. Furthermore, elevated temperatures were found to decrease persistence. Differences in dissipation among the urban materials were linked to their physicochemical properties as well as diffusion/matrix retention. The challenges of CWAs recovery one-month post-exposure are highlighted in this study, providing insights for improving sampling, identification, and decontamination strategies under realistic conditions.

The growing accumulation of microplastics (MPs) in the environment highlights the urgent need for greener, more scalable treatment options compared to traditional physicochemical methods. In this review, we summarize progress in the microbial breakdown and enzymatic depolymerization of major plastic types, mapping out the distinct biochemical degradation routes for polyolefins, polystyrene, polyvinyl chloride, and polyesters. To clarify how these processes are validated experimentally, we detail the key analytical tools used to confirm MP biodegradation. We also evaluate the practical engineering limitations that currently prevent these technologies from being deployed at an industrial scale. Key hurdles discussed include short hydraulic retention times in standard wastewater treatment plants, interference from complex pollutants in real-world matrices, and the poor kinetic rates of enzymes when applied at economically realistic concentrations. To tackle these scalability issues, we explore several promising solutions, including advanced chemo-physical pretreatments and the genetic engineering of microbes for upcycling plastics into valuable biochemicals. Ultimately, these advances in biotechnology lay the groundwork for integrating biological plastic degradation into broader, closed-loop waste management systems, offering a practical route to achieving a true circular economy.

The corrosion of sea-dumped munitions represents a long-term source of explosive contamination in marine environments. However, the coupled processes controlling release and transformation remain poorly understood. This study presents a laboratory-scale munition analogue that simultaneously quantifies corrosion, TNT release, and transformation within an intact corroding system under controlled marine conditions. Cast iron casings (height = 4.2 cm, radius = 0.3 cm, and thickness = 0.045 cm) weighing 1.9 ± 0.15 g containing TNT cylinders of dimensions 3.9 cm height, 0.2 cm radius, and 1.1 g in weight were exposed to synthetic seawater for 90 days. Corrosion resulted in substantial material degradation, with a mass loss of 3.2 % and a thickness reduction of 17.7 %. The corrosion rate was 0.33 ± 0.05 mm year⁻¹ and the TNT release rate was found to be 1.61 × 10⁻¹⁰ kg s⁻¹ (13.9 mg day⁻¹), which aligns with the measured aqueous concentrations using HPLC (<1 mg L⁻¹) in the 15 L system. However, the concentration profiles showed pronounced temporal fluctuations, indicating non-steady release behaviour. A Buckingham Π-based analysis yielded a dimensionless coefficient (β ≈ 10⁻⁸), indicating that release was strongly constrained by casing geometry and internal transport limitations. Additionally, corrosion-derived iron minerals may contribute to TNT transformation, as observed by the enhanced formation of ADNT. Collectively, the results demonstrate that TNT fate is governed by coupled interactions among structural degradation, diffusion-limited transport, and corrosion-driven geochemical processes. The proposed mechanistic framework and Buckingham Π-based scaling approach provide a basis for improving predictive assessments of long-term contaminant release from sea-dumped munitions.

This study underscores the immense potential of Klebsiella pneumoniae as a robust cell factory for efficient valorization of arabinose- and glucose-rich sugar beet pulp hydrolysates into 2,3-butanediol, a product with huge commercial potential.

The co-occurrence and combined dietary health risks of per- and polyfluoroalkyl substances (PFASs) and heavy metals (HMs) in rice remain poorly understood. This study analyzed 29 PFAS compounds and 4 HMs in rice tissues collected from paddy fields. HFPO-DA was dominant in brown rice (4.84–15.99 ng/g), while PFOA primarily accumulated in leaves and straw. Cd and Cu showed elevated grain concentrations. PFASs exhibited higher bioaccumulation and translocation factors than HMs, especially in aboveground tissues, whereas Cd and As accumulated most in roots. Correlation analyses suggest dual root and foliar uptake contributed to HFPO-DA and Cd grain accumulation. Dietary assessment revealed that HFPO-DA, PFOS, Cd, and Cu in brown rice exceeded safety thresholds across different age groups. Specifically, the cumulative hazard index (HI) reached 10.7 in brown rice for toddlers, twice that of white rice, raising significant health risk concerns. These findings provide critical insights for future food safety monitoring and risk management.

Reliable, targeted sampling of chemical warfare agent (CWA) residues following explosive dissemination remains a critical challenge in forensic chemistry and chemical incident response. This study integrates controlled detonation experiments with quantitative residue analysis and statistical analysis, demonstrating the importance of matrix-specific and complementary sampling approaches for accurate residue detection. Two physicochemically diverse CWA simulants, methyl salicylate and malathion, as analogues for sulfur mustard (HD) and VX, were applied to steel ball bearings using cotton-polyester fabric or cotton wool across three deposition methods to evaluate their influence on simulant retention following detonation. Residues were quantified by high-performance liquid chromatography (HPLC) to assess both retention and secondary transfer. Results show matrix-dependent residue behaviour, with fabric consistently exhibiting the highest retention of methyl salicylate (up to 6 mg/L), while non-porous materials such as ball bearings and plastic fragments generally retained minimal residues. Container fragments selectively retained malathion more effectively, consistent with differences in physicochemical properties. Secondary transfer was confirmed by the detection of residues on initially uncontaminated fragments. Statistical significance of retention and transfer trends was evaluated using binary logistic regression. Findings demonstrate that matrix characteristics, deposition method, and simulant physicochemistry strongly govern post-blast residue patterns of CWAs. Importantly, residual contamination on fragments may remain sufficient to pose transdermal and/or inhalation hazards, given the extreme acute toxicity of VX, which exhibits an oral LD50 of 0.04 mg/kg. Overall, the study provides novel, quantitative insight into post-detonation behaviour, informing forensic sampling strategies, hazard management, and chemical, biological, radiological, and nuclear (CBRN) incident response.