Mirel Glevitzky

Growing interest in waste valorization and sustainable cleaning products motivated the development and characterization of an eco-friendly powder detergent based on soap derived from waste cooking oil and enriched with juniper essential oil. Waste sunflower oil was pretreated and, together with coconut oil, subjected to cold saponification; the resulting soap base was incorporated at 30% into a detergent formulated with sodium carbonate, sodium bicarbonate, sodium percarbonate and natural zeolite. The raw materials—waste sunflower oil, coconut oil, clinoptilolite and juniper essential oil—were characterized using physicochemical analyses: DSC for coconut oil and Raman spectroscopy for oils, XRF for zeolite, and physicochemical analysis and GC-FID for the essential oil. The soap exhibited pH 9.93, 14.8% moisture, 24 cm foam capacity, and a 3.0 g/min dissolution rate, versus pH 9.33, 10.5% moisture, 12 cm foam capacity, and 1.0 g/min dissolution rate for the detergent. In vitro antibacterial activity was assessed against Escherichia coli and Staphylococcus aureus by agar well diffusion. At 500 mg/mL, inhibition zones reached 8.53 and 17.00 mm for the soap and 7.47 and 15.03 mm for the detergent. Two-way ANOVA confirmed significant effects of sample type and concentration (p < 0.001), with the strain being the dominant source of variation (η²_p = 0.983); both products reached 71.0–87.7% of a commercial reference and were more effective against S. aureus. Antibacterial activity decreased significantly with decreasing concentration (p < 0.001 for all pairwise comparisons), while both formulations showed greater efficacy against S. aureus than against E. coli. The results demonstrate the potential for valorizing waste cooking oil into functional cleaning products and highlight the possibility of contribution of juniper essential oil to the antimicrobial performance of the formulations, supporting the development of sustainable and environmentally compatible detergent products within a circular economy approach.

Waste cooking oils represent an important household and institutional waste stream with significant environmental impacts when disposed of improperly. In the context of the circular economy, this study investigates their valorization through conversion into solid soaps by cold-process saponification. The oils were pretreated by mechanical filtration, chemical purification with 10% NaCl solution and natural purification using eggshells, and their quality was assessed through total polar compounds, acid, peroxide and iodine values. Raman spectroscopy showed similar molecular profiles of the soaps obtained from the two purification treatments. The purified oils were converted into solid soaps using sodium hydroxide with a 5% superfat, and essential oils of Pimpinella anisum L., Ocimum basilicum L. and Coriandrum sativum L., characterized by GC-FID, were incorporated to provide an additional functional characteristic. The soaps were evaluated for physicochemical characteristics and antimicrobial activity against Staphylococcus aureus and Escherichia coli. All soaps showed antibacterial activity, with inhibition zones up to 10.87 mm against S. aureus and 7.77 mm against E. coli for basil essential oil soap. Two-way ANOVA confirmed significant effects of sample type and concentration (p < 0.001), the essential-oil soaps exceeding the base soaps by 0.83 and 1.88 mm, while no statistically significant difference was detected between soaps prepared from the two purification treatments. Waste cooking oils thus constitute a potential secondary raw material for functional soap production. The proposed approach demonstrate that, following appropriate pretreatment, waste cooking oils constitute a viable secondary raw material for the production of solid soaps with satisfactory quality and preliminary in vitro antimicrobial activity, supporting waste valorization and contributing to the development of circular economy approaches.

Steel dust is a waste generated during steelmaking in an electric arc furnace (EAF), which contains a high proportion of iron-bearing compounds, leading to the inclusion of this waste as a resource in the circular economy for steelmaking. In addition to the limitation related to granulation (the waste must be processed to obtain larger particle sizes), a limiting factor is the increasingly high Zn content due to the low-quality ferrous charge. For the recycling of steelmaking dust, preliminary processing is necessary to reduce zinc. The paper presents, in addition to qualitative characterization of steel dust, laboratory experiments on the compositional changes associated with zinc redistribution applying the hydrometallurgical leaching process in an alkaline environment, using sodium hydroxide (NaOH). The changes in the chemical composition were identified and evaluated using X-ray fluorescence (XRF) and energy-dispersive X-ray spectroscopy (EDX). The experiments consisted of treating steel dust samples with 5 M NaOH at 25, 70, 80 and 90 °C for 60 min, using solid-to-liquid ratios of 10, 15, and 25 g/L. The results indicate a reduction in ZnO content ranging from 4.52% to 16.82%, as determined from Na₂O-free normalization data. Room-temperature samples show only marginal changes in ZnO content. The XRF and EDX analyses indicate a moderate and condition-dependent redistribution of zinc in the solid phase after alkaline treatment, as evaluated using Na₂O-free normalized data. These values are derived exclusively from solid-phase measurements (XRF/EDX) and do not include zinc in the leachate; therefore, true zinc extraction efficiency cannot be determined. The research results attest to the viability and efficiency (as a solid-phase compositional transformation process) using NaOH as a leaching agent for the studied steel dust, thus providing a potential pathway for improved waste recycling in the steel industry.

Occupational safety is increasingly addressed through engineering-based, proactive risk management approaches that emphasize early identification and mitigation of hazards within industrial systems. In manufacturing environments, the analysis of minor process deviations, near misses, and low-impact operational failures provides critical insights for improving system reliability and safety performance. This paper proposes an integrated engineering framework that combines the 5M model (Environment, Man, Method, Material, Machine) with Source–Detection Matrix analysis to support structured identification, classification, and control of safety-related process deviations. The approach enables systematic root-cause analysis by categorizing contributing factors according to the 5M model, followed by mapping each deviation based on its origin and point of detection within production processes. The methodology was validated through case studies conducted in cosmetics and perfumery manufacturing, involving process-related hazards such as electrical failures and exposure to volatile substances. Validation was also supported by operational data collected over two 6-month periods before (n₁) and after implementation (n₂), based on incident reports, near-miss records, nonconformity reports, and internal audit data (n₁ = 128; n₂ = 95). Quantitative results show improved safety performance, including an increase in Detection at Source Rate from 42% to 74% and a reduction in Minor Incident Frequency from 11 to 5 cases/month. The results demonstrate that integrating causal analysis with detection mapping enhances early-stage identification of process deviations, effectively limiting failure propagation across operational stages and improving overall process safety performance. The proposed framework provides a practical and data-driven tool for improving process reliability, operational safety, and continuous improvement in complex manufacturing environments.

Formaldehyde emissions from urea–formaldehyde (UF)-bonded particleboards remain a significant environmental and health concern. This study evaluates the effectiveness of flours as bio-based formaldehyde scavengers in particleboard production. Food-based flours (soy, wheat, green pea) and feed flours (hemp, maize DDGS, feather meal) were incorporated into UF resin at concentrations of 0.3–2.0%. Resin characterization included pH, viscosity, gelation time, solid content, and free formaldehyde, while rheological behavior was monitored at 70 °C and 90 °C. The addition of flour decreased pH from 9.1 to 7.9 and increased viscosity from 414 to up to 1600 cP, depending on flour type and dosage. Free-formaldehyde content was reduced from 0.17% to as low as 0.08%, with the most effective reduction observed for hemp flour. At industrial scale, particleboards produced with 0.5% soy and hemp flours significantly reduced free formaldehyde, with emission values of 3.26 mg/m² and 3.05 mg/m², corresponding to reductions of 66–70% compared to the reference (3.97 mg/m²). Mechanical properties, including density (652–665 kg·m⁻³), bending strength (13.2–14.1 N·mm⁻²), and internal bond (0.42–0.45 N·mm⁻²), were maintained within acceptable limits. While feed flours such as feather meal showed strong scavenging potential, they caused significant viscosity increases (up to 1800 cP), limiting processability. These findings demonstrate that adding low levels of flour, particularly soy or hemp, is an effective, renewable, and low-cost strategy to reduce formaldehyde emissions in UF-bonded particleboards, supporting the production of safer and more sustainable wood-based composites.

This study presents an integrated approach combining environmental risk assessment and experimental performance evaluation for asphalt production plants incorporating reclaimed asphalt pavement (RAP). Unlike previous studies, which focus separately on mechanical performance or environmental impact, our methodology applies a semi-quantitative Environmental Impact Score (EIS), calculated using legal requirements (L), pollutant characteristics (P), and control measure effectiveness (C). The EIS framework is based on ISO 14001 and ISO 31000 principles. The results indicate that significant impacts are mainly associated with high-temperature processes and hazardous materials, while mitigation measures effectively reduce residual risks. The experimental investigation compared conventional asphalt mixtures with mixtures containing 9.71% RAP across different bitumen contents. Key quantitative findings include a 3-point increase in EIS for RAP mixtures due to higher volatile organic compound (VOC) emissions and a 3–8% improvement in Marshall stability and stiffness at lower bitumen contents (3.8–4.2%). The results demonstrate that RAP can enhance mechanical performance while supporting circular economy objectives, provided that environmental risks are actively managed through process control and mitigation measures. This work highlights the novel integration of quantitative environmental scoring with laboratory validation, providing a reproducible framework for sustainable and risk-informed asphalt production.

The valorization of waste cooking oils (WCOs) provides a strategy to reduce environmental impact while converting residues from the food industry into valuable products. This study developed and characterized antimicrobial soaps from purified WCOs (sunflower, palm, and pumpkin oils) enriched with natural bioactive ingredients. WCOs were purified by filtration, treatment with 10% NaCl, and bleaching with 3% H₂O₂, followed by cold saponification with NaOH. Twelve soap formulations were prepared, including six enriched with bee products (propolis, poly-floral honey, linden, acacia, honeydew, and sunflower) and six enriched with essential oils (EOs) (clove, rosemary, mace, nutmeg, white pepper, and juniper). The WCOs, natural bioactive ingredients, and soaps were characterized using physico-chemical methods (FTIR, GC-FID, phenols, flavonoids, etc.), while their antibacterial activity was determined against two microbial strains: Staphylococcus aureus and Escherichia coli. The antimicrobial activity of soaps is related to their alkaline pH, while the addition of honey, propolis, or EOs contributes to additional antimicrobial effects. Among honey- and propolis-enriched soaps, those with propolis produced the largest inhibition zones (up to 8.67 mm for S. aureus and 7.0 mm for E. coli). EO-based soaps exhibited higher activity, with rosemary EO-based soap showing the largest zones (up to 9.5 mm for S. aureus and 7.5 mm for E. coli). These data support the potential of enriched soaps containing honey, propolis, and EOs for antimicrobial applications, highlighting their value as a sustainable alternative in the valorization of WCOs.

The valorization of waste materials is essential for sustainability, with used cooking oils (UCOs) offering potential for transformation into valuable functional products. The study investigates the oxidative stability of sunflower and olive oils subjected to high temperatures (160–200 °C) and frying on their physico-chemical properties (acidity, peroxide and iodine value, total polar compounds). Significant deterioration occurred above 180 °C, with increased peroxide and polar compounds and reduced iodine values. A technological process for the purification and saponification of UCOs (sunflower, olive, and palm oils) was developed, demonstrating the potential to transform pollutant waste into a valuable and sustainable product—soap. The incorporation of oregano and thyme essential oils (EOs), identified by GC-FID as rich sources of carvacrol, thymol, p-cymene, and limonene, improved the functional properties of the soaps. The antimicrobial activity of soaps largely relates to their alkaline pH, while the incorporation of EOs contributes to additional antimicrobial effects, obtaining zones of inhibition of up to 10.8 mm against Staphylococcus aureus and up to 7.6 mm against Escherichia coli for palm oil. The study highlights a sustainable approach that transforms waste oils into functional soaps with EOs for added antimicrobial benefits.

Occupational health and safety (OHS) is essential for protecting the life, health, and physical integrity of workers. In a complex and dynamic professional context, the prevention of occupational risks has become a priority for employers and decision-makers, going beyond legal compliance to create a safe and efficient work environment. This article explores the history and the main theoretical aspects of OHS and explores the implementation of the ISO 45001 standard and introduces managing workplace health and safety (WHS) risks based on the 5M Method and a weighted composite algorithm for OHS risk assessment integrating factors such as severity, probability, frequency of exposure, number of exposed employees, organizational response capacity, and incident history. Applied in a mixed industrial case study, this approach demonstrated superior risk prioritization compared to the classic severity–probability model. The findings have practical applications: organizations can use the Weighted Composite Score to prioritize interventions, allocate resources efficiently, and prevent high-risk incidents. The approach is adaptable across industries, supporting data-driven safety decisions. The integration of this method supports ISO 45001’s principles of a systematic, proactive, and continuous improvement approach to OHS management.

The Arieș River, in the Apuseni Mountains of Romania, has been historically impacted by gold mining, resulting in elevated concentrations of metal trace elements. This study assessed the river’s ecological status between 2022 and 2024 by integrating physico-chemical parameters at four sites and diatom-based bioindicators at the same sites in 2024 across monitoring sectors. Key results showed strong mining influence downstream of Baia de Arieș, with episodic acidification (pH down to 5.7), elevated conductivity (>400 μS/cm), and notable exceedances in metal trace elements, particularly Cu (up to 237 μg/L) and Cd (up to 4.18 μg/L). Analysis showed a dominance of α-mesosaprobic taxa (e.g., Amphora ovalis, Navicula cryptocephala, Nitzschia inconspicua), including teratological forms, at polluted sites, while sensitive species persisted upstream. Multivariate analyses indicated that metal trace elements and nutrients are the main drivers of chemical and biological patterns. These findings highlight diatoms as sensitive bioindicators of mining-related impacts. Incorporating diatom-based monitoring into management strategies can support early detection of pollution and more effective protection of freshwater ecosystems.