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.

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.

The article focuses on verifying the potential of using cellulose obtained from waste cardboard to improve the soil’s water retention capacity, depending on its texture and type, in accordance with the principles of the circular economy. The study compares reference cellulose (RFC) and waste carton-extracted cellulose (WCC) in terms of their structure and water-holding capacity (WHC), using FTIR spectroscopy and experiments across various soil types. Results showed that WCC has a significantly higher WHC (12.6 g/g) than RFC (0.75 g/g) due to its greater proportion of amorphous sections and the presence of lignin and hemicellulose. In contrast, the high crystalline content of RFC limits its water sorption capabilities. Soil texture and soil organic matter (SOM) play a crucial role in water retention. The highest WHC values were observed in fine-grained soils classified as silt loam. The study confirms that SOM has a stronger influence on WHC than texture alone. Applying WCC led to a linear increase in WHC across different soil types. Even soils with initially low WHC showed notable improvement with low doses of WCC (1%). The findings highlight the potential of waste carton-extracted cellulose as a soil amendment to enhance water retention in agricultural soils, especially in adapting to climate variability and drought conditions.

The use of waste from the regional production of waste wood, waste paper, and cardboard in the form of briquettes may be causing an increase in local emissions, both of major elements and trace elements. When burning paper and cardboard briquettes, more than 70% of Mn, Zn, As, and Pb is released into the air from the total content of trace elements in the fuel. The largest amounts of major and trace elements are released when burning paper briquettes (56 g/kg of fuel); half of these amounts are released from burning briquettes from waste wood and coal (23 g/kg of fuel). The pursuit of alternative uses for those cardboard components that are not suitable for recycling cannot be directed to the production of briquettes for residential combustion in the framework of the application of the principles of the circular economy. In particular, the high concentrations of undesirable elements in the emissions released in the gas phase into the atmosphere are an obstacle existing even when the parameters of the PM₁₀ emissions of a boiler are met. This is related to the high ash content of the cardboard (13.5%). Waste paper or cardboard could be added to waste wood at a maximum of 10% to make the pollution produced comparable to the burning of coal briquettes.

The chemical complexity of post-consumer plastics represents a major challenge for achieving high-quality recycling. In this study, post-consumer high-density polyethylene (HDPE) packaging materials were analysed using pyrolysis–gas chromatography–mass spectrometry (Py-GC/MS) to investigate relationships between compound origin, degradation pathways, and contaminant profiles. More than one hundred organic compounds were detected and classified into four main groups: product-related inputs, polymer formulation chemistry, polymer degradation processes, and external contamination. Polymer degradation products, particularly radical rearrangement and cyclisation compounds, represented the most diverse group, indicating advanced transformation of the polymer matrix associated with repeated processing. Additive-derived compounds, including phenolic structures and epoxide-containing species, contributed to the pool of non-intentionally added substances (NIAS), while persistent compounds, such as fluoropolymer-derived residues, were detected across most samples. In contrast, product-related inputs showed high variability and a generally lower contribution. Multivariate analysis revealed that samples were not clustered according to product category but rather distributed along gradients defined by degradation, additive transformation, and contamination processes. These findings demonstrate that the chemical composition of recycled HDPE is determined or influenced by multiple independent factors. The results support the need for chemistry-informed recycling strategies.

Recycled polyethylene terephthalate (rPET) intended for food-contact applications contains complex mixtures of non-intentionally added substances (NIAS) originating from polymer degradation, recycling, packaging-related inputs, and external contamination. Although non-targeted analytical techniques can characterise these complex chemical fingerprints, a standardised framework for their systematic interpretation is lacking. This study introduces a literature-informed, pattern-based framework for interpreting Py-GC/MS fingerprints of commercial PET bottles. Twenty-two commercial PET beverage bottles were analysed by pyrolysis–gas chromatography–mass spectrometry (Py-GC/MS), and detected compounds were organised into four diagnostic profile groups: PET transformation products (C-PET), packaging-associated compounds (E-PS/PVC/FCM), mixed-origin compounds (M-MIX), and condensed aromatic structures (A-AROM). Principal component analysis and a composite Quality Index (QI) were used to evaluate chemical variability. PET transformation products formed a consistent chemical baseline across all samples, whereas chemical variability was primarily associated with packaging-associated compounds and condensed aromatic structures. Bottles containing 100% rPET spanned the full range of chemical profiles, suggesting that the observed variability may be influenced more strongly by feedstock quality, packaging-related inputs, and processing history than by declared recycled content alone. The proposed framework enables a systematic interpretation of Py-GC/MS fingerprints through diagnostic chemical patterns rather than unique source attribution of individual compounds. The proposed framework provides a scalable methodology for comparative evaluation of recycled PET. It highlights that improving chemical quality requires controlling feedstock purity, packaging-related contamination, and processing conditions rather than relying solely on recycled content.