Waste paper represents a valuable secondary source of cellulose fibres, contributing to the reduction of virgin wood consumption in paper production. To support sustainable development objectives, the integration of natural fibres with synthetic polymers is increasingly explored across industrial sectors. Reliable use of waste paper materials requires baseline data on pollutant content and migration potential. In this study, cellulose fibres were separated using 0.2 M acetic acid (CH ₃ COOH) extraction, followed by washing. This method effectively removed precipitated calcium carbonate-based filler from office paper, achieving an extraction efficiency of 86%. A total of 138 compounds were identified in waste paper, originating from: virgin wood ( n = 31), paper manufacturing and recycling processes ( n = 19 + 15 fragrance compounds), and printing inks ( n = 67), with solvents ( n = 25) forming the largest subgroup. Additional substances were associated with surface treatments and ink formulations. Compound hazard profiles were assessed using the Globally Harmonized System (GHS). The identified substances were, among others, persistent organic pollutants, including benzophenone , butylated hydroxytoluene , and bis(2-ethylhexyl) phthalate , bisphenol A, and bisphenol S , while solvents exhibited the highest proportion of hazardous classifications. Following CH ₃ COOH extraction, concentrations of hazardous solvents were reduced by 93%, indicating the method’s potential for pollutant mitigation in fibre recovery.

Soot and ash as residues from the combustion of peat briquettes were analysed by chemical and mineralogical methods. The study aimed to characterize combustion in domestic boilers of two different emission classes. Ten samples of soot deposited in exhausting ways of boilers were obtained (five of each emission class). The analyses of organic substances in soot were performed using a combination of the methods for the determination of elemental and organic forms of carbon with analytical pyrolysis. Pyrolysis gas chromatography with mass spectrometric detection (Py-GC/MS) allowed the identification of organic compounds belonging to twenty different groups. The major and minor elements in peat briquettes, char and soot, were determined by X-ray fluorescence spectroscopy. The identification of grains and the chemical character of soot was performed using a scanning electron microscope with energy dispersive X-ray spectrometry. The mineral phases in ash were determined by X-ray diffraction. The behaviour of the inorganic elements in combustion products (ash and soot) was studied by means of an enrichment factor. The analytical results are used for characterizing the technological conditions of combustion. The soot deposits from the more advanced boilers with increased combustion temperature contain more organic compounds which indicate the highly carbonized cellulose (benzofurans and dibenzofurans). The increased combustion temperature is indicated by increased concentrations of heterocyclic and aliphatic nitrogen compounds, while the total concentrations of nitrogen in soot from boilers of both types are comparable.

Volatile organic compounds (VOCs) emitted from indoor surface coatings can significantly impact indoor air quality and health. This study compared emissions from water-based polyurethane (PUR) and acrylate–polyurethane (ACR–PUR) coatings, identifying 94 VOCs across 16 chemical classes. Time-resolved concentrations were analysed via Principal Component Analysis (PCA), which revealed distinct temporal emission patterns and chemically coherent clusters. Aromatic hydrocarbons, alcohols, esters, and isocyanates dominated the emission profiles, with ACR–PUR releasing markedly higher concentrations of symptom-relevant compounds. Acute exposure was linked to toluene, styrene, phenol, and methyl butyl ketone (MBK), which decreased sharply within 60 days, while compounds such as 1,3-dioxolane, isopropylbenzene, and ethenyl acetate exhibited persistent emissions, suggesting increased chronic risk. Although total VOC levels remained below the German UBA “excellent” threshold (<200 µg/m³), neurotoxic and carcinogenic compounds remained detectable. The combination of PCA-based temporal insights with toxicological profiling and emission transfer dynamics offers a refined framework for indoor air risk assessment. These results underscore the need to complement total VOC indices with symptom-oriented, time-resolved screening protocols to better evaluate SBS risk in indoor environments using water-based coatings.