Presence Of Polycyclic Aromatic Hydrocarbons Research Articles

The levels of polycyclic aromatic hydrocarbons in traditional cigarettes and E-cigarettes in Saudi Arabia markets: a comparative risk assessment study

BackgroundTwo validated and effective extraction techniques have been developed to ascertain the presence of polycyclic aromatic hydrocarbons (PAHs) in traditional cigarettes and E-cigarettes. PAHs are a class of chemicals that occur naturally, and these contaminants may cause cancer and other harmful effects in human beings. Traditional cigarettes and E-cigarettes contain many PAHs.MethodIn terms of linearity, limit of detection, limit of quantification, accuracy (%), and precision (%), the two in-house lab setups for 7PAHs extraction from traditional cigarettes and E-cigarette were validated using high-performance liquid chromatography-fluorescence detection.ResultsThe concentration of Σ7PAHs for traditional cigarettes and E-cigarettes ranged from 6.23 ± 0.04 ng/cig to 75.61 ± 0.02 ng/cig, and non-detectable to 3.56 ± 2.71 ng/puff. The PAHs recovery in traditional cigarettes and E-cigarettes ranged from 92.74–110.45%, and 97.20–111.74%. The toxicity of equivalent (TEQs) of carcinogens revealed that traditional cigarettes brands have higher TEQs than E-cigarettes.ConclusionThis study highlights the detection of 7PAHs levels and its risk assessment in product brands for traditional cigarettes and E-cigarettes marketed in Saudi Arabia. The results suggested that the developed methods are a precise and versatile approach for measuring 7PAHs in traditional cigarettes and E-cigarettes.

Toxicity prediction based on PAHs in fruits and vegetables − A machine learning approach

This study analyses the toxicity levels of fruits and vegetables by identifying the presence of polycyclic aromatic hydrocarbons (PAHs), particularly in areas affected by industrial and vehicle pollution. The presence of PAHs on plant surfaces, caused mostly by air pollution particulate matter, raises serious concerns about the nutritional value of these foods. Traditional techniques for measuring PAH levels include Gas Chromatography/Mass Spectrometry (GC/MS) and High-Performance Liquid Chromatography (HPLC). Although successful, these procedures are expensive and time-consuming. Toxicity detection is often based on expert knowledge or experimental analysis relative to the European Food Safety Authority’s (EFSA) limits. In response to these challenges, this work uses artificial intelligence approaches to determine toxicity levels using 16 PAHs. Data on PAH concentrations in fruits and vegetables were collected from a variety of sources, classified as safe or harmful, and verified using statistical analysis. The validated dataset was subsequently classified using several machine learning techniques. The level of toxicity is scaled and compared to the expected outputs using the results obtained from the neural network. An experimental investigation validates the promising findings of level of toxicity classification using artificial intelligence approaches, which are then evaluated statistically. The study shows that machine learning algorithms obtained classification accuracies of over 90 %, including the evaluation of harmfulness. The accuracy for the two-class (Safe and Unsafe) category was 98.27 %, while the accuracy for the four-class (No harm, Low harm, Moderate Harm, and Severe harm) category was 98.68 %. These findings highlight the potential of artificial intelligence in improving food safety and public health by presenting an innovative multidisciplinary method to assessing the impacts of environmental pollutants on the edibility of fruits and vegetables in the context of climate change.

Evaluation and Determination of the Physical Properties of Gasoline and the Presence of Fine Particles in the Ten Districts of the City of N'djamena

The context, which allowed to write this article is the fact that we have noticed an increase in the environmental impact caused by the poor management of car parks and fuel sellers as well as the proliferation of service stations that do not respect any standards. The illegal storage and marketing of petroleum products, especially gasoline, in the city of N'Djamena is the main factor of vulnerability and criticality of air pollutants, thus demonstrating the growing environmental impact in the city of N'Djamena. The presence of Polycyclic Aromatic Hydrocarbons (PAHs) as well as that of fine particles which are part of the Persistent Organic Pollutants (POPs) and characterize by their toxicities, their persistence in the environment, their bioaccumulation in living tissues, and their long-distance transport. Thus, the main objective of this work is to determine and evaluate the physical properties of gasoline and the presence of fine particles in the ten districts of the city of N'Djamena. These are the species sold on the street and presenting a danger to users. The main idea would be to look for gas stations and points of sale that comply with the regulations in force and those that do not. Then physical analyses were carried out on different types of gasoline consumed and then the air quality was measured with a Purple Air sensor. In conclusion, a complete structure of the ten districts with their degrees of pollution as well as the number of gas stations and fuel sellers on the street will be listed.

Polycyclic aromatic hydrocarbons (PAHs) in crude oil-contaminated water and soil and their removal using locally available plant materials

ABSTRACT The presence of polycyclic aromatic hydrocarbons (PAHs) in water and soil can be harmful to human life when ingested. PAHs are determined in the water and soil of the B-Dere community of Rivers State, Nigeria. The extent of risk and source identification were carried out. The water samples were treated with garlic and Moringa seed extracts, while the soil samples were treated with garlic and Fenton oxidation reagents. PAHs were extracted before and after treatment. The gas chromatograph mass spectrometer analyses showed 13 PAHs in the water and 10 PAHs in thesoil. The highest concentration in water was recorded for benzo(ghi)perylene, with a mean value of 27.7 ± 0.25 ngL−1, while that of soil was recorded for benz(a)anthracene, with a mean value of 14.4 ± 0.631 ngkg−1. The source of PAHs in water was pyrogenic, while that of soil was petrogenic. Garlic extract removed 100% of benz(a)anthracene and benzo(b)fluorothane from the water, while Moringa removed 100% biphenylene from the water. However, garlic extract removed 2.59% of acenaphthylene, while Fenton reagents removed 100% of anthracene, phenathrene, and chrysene from the soil. Moringa seed and garlic extracts can be used in PAH's polluted water treatment.

Novel insights into the factors influencing rhizosphere reactive oxygen species production and their role in polycyclic aromatic hydrocarbons transformation

Reactive oxygen species (ROS) are recognised as pivotal biogeochemical process drivers. However, the factors influencing ROS production in the rhizosphere and their role in pollutant transformation remain elusive. We investigated ROS with a focus on spatiotemporal variations in superoxide radicals (O2•−), hydrogen peroxide (H2O2), and hydroxyl radicals (•OH) in the rhizosphere of maize during root development, and elucidated the impact of environmental conditions on ROS production. In-situ visualisation by fluorescence imaging showed that ROS hotspots gradually shifted from seminal to lateral roots during maize growth, indicating that newly developed roots are the major contributors to ROS production. The three types of ROS contents changed with root growth, suggesting that root development regulates ROS production. The ROS contents reached a maximum at 25 °C and 45% maximum field capacity. Both ambient temperature and soil moisture indirectly influenced ROS production by regulating the release of root exudates to induce changes in water-soluble phenols and dissolved organic carbon (DOC). In contrast, ROS content gradually increased with oxygen availability, which directly mediated ROS generation by acting as a precursor. More interestingly, the presence of polycyclic aromatic hydrocarbons (PAHs) significantly enhanced ROS generation, which further promoted PAH removal with a contribution of 31.4–43.3%. These findings provide new insights into the occurrence, distribution, and environmental effects of ROS in the rhizosphere.

Characterising polycyclic aromatic hydrocarbons in road dusts and stormwater in urban environments.

The presence of polycyclic aromatic hydrocarbons (PAHs) pollution on urban road surfaces is one of the major environmental concerns. However, knowledge on the distribution variability of PAHs in road dusts (RDS) and stormwater is limited, which would restrict the further risk evaluation and mitigation implementation of PAHs in road stormwater runoff. This study collected RDS samples and stormwater samples on fourteen urban roads in Shenzhen, China. This study investigated the variation of sixteen PAHs species in RDS and stormwater, and further evaluated the intrinsic and extrinsic factors which influence PAHs accumulation on urban road surfaces. The research outcomes showed significant differences on spatial distribution of PAHs in RDS and in stormwater. The land use types, industrial, commercial and port areas and vehicular volume have a positive relationship with PAHs abundance while dust particle size showed a negative correlation with PAHs abundance. For two phases in stormwater, fluctuation of PAHs with the rainfall duration in total dissolved solid (TDS) was more intensive than in dissolved liquid phase (DLP). This indicated when PAHs attached to RDS enter stormwater, most of PAHs still tend to be on solid particles than in liquid. The study outcomes are expected to contribute to efficient designs of PAHs polluted stormwater mitigation.

Assessment of polycyclic aromatic hydrocarbon (PAH) levels and health risks in kitchen dust from wood, kerosene, and gas cooking systems in Cumilla, Bangladesh

This study investigates the presence of polycyclic aromatic hydrocarbons (PAHs) in kitchen dust from households in the Cumilla District of Bangladesh, utilizing three different cooking systems: wood, kerosene, and gas. Sixty dust samples were collected from various kitchen surfaces and analyzed for 18 PAH compounds. The extraction and analysis of PAHs were performed using gas chromatography-mass spectrometry (GC-MS) with selective ion monitoring (SIM) mode. The results indicated significant variations in PAH concentrations across different cooking systems, with the highest levels observed in kitchens using wood stoves, followed by kerosene and gas stoves. Diagnostic ratios were used to identify the sources of PAHs, revealing a combination of pyrogenic and petrogenic origins. Health risk assessments, including Incremental Lifetime Cancer Risk (ILCR) and Hazard Index (HI), were conducted to evaluate the potential risks associated with PAH exposure. The findings demonstrated a higher carcinogenic risk associated with wood stove systems, while kerosene and gas systems posed comparatively lower risks. The study's findings have practical implications for public health and policy development, as they underscore the need for continuous monitoring of indoor PAH levels and the development of policies to mitigate exposure, highlighting the critical importance of addressing indoor pollution to ensure public health safety.

Preliminary study for Polycyclic aromatic Hydrocarbons mobilization from contaminated marine sediment using synthetic and natural surfactants

The persistent presence of Polycyclic Aromatic Hydrocarbons (PAHs) in soils and sediments due to their chemical properties requires new methods to mobilize and make them more available for remediation purposes. In this work, the evaluation of the abilities of eight different non-ionic sugar-based and totally biodegradable surfactants, such as synthetic alkyl polyglycosides (APGs), biological sophorolipids (SLs) and biological rhamnolipids (RLs), was conducted in order to provide a preliminary guideline for the selection of the surfactant and the technical approach for PAHs extraction from the sediment. The reference sample was a marine sediment collected from Bagnoli (Naples, Italy) that was characterized to evaluate the level of PAHs contamination, which resulted equal to 3.51 g Kg−1 of total PAHs in the sediment. By using surfactants solutions with a surfactant concentration five times greater than critical micelle concentration (Cs = 5x CMC), a preliminary washing test in batch configuration was conducted, then followed by multiple consecutive washes (MCW) of the sediment to assess the solubilization of PAHs from the sediment by the action of selected surfactants. The results show an evident advantage given by the employment of each studied surfactant in mobilizing PAHs, compared to distilled water as benchmark. In detail, the synthetic alkyl polyglycosides APG2 led to a 3.4 % of total PAHs mobilization in the preliminary washing test with a maximum peak of 9.8 % for a single compound. The MCW test demonstrates that more consecutive washes can increase the amount of total PAHs removed, with a similar contribution from each wash, and that biosurfactants can be more attractive after several washes thanks to the increased capacity of PAHs mobilization. Interestingly, the high efficiency of surfactant to mobilize PAHs makes the soil washing a more attractive technology for removing PAHs from the marine sediments.

Presence of polycyclic aromatic hydrocarbons and persistent organochlorine pollutants in human Milk: Evaluating their levels, association with Total antioxidant capacity, and risk assessment

Breastfeeding provides numerous health benefits for both infants and mothers, promoting optimal growth and development while offering protection against various illnesses and diseases. This study investigated the levels of polychlorinated biphenyls (PCB), organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) in human milk sampled in Zadar (Croatia). The primary objectives were twofold: firstly, to evaluate the individual impact of each compound on the total antioxidant capacity (TAC) value, and secondly, to assess associated health risks. Notably, this study presents pioneering and preliminary insights into PAH levels in Croatian human milk, contributing to the limited research on PAH in breast milk worldwide. PCB and OCP levels in Croatian human milk were found to be relatively lower compared to worldwide data. Conversely, PAH levels were comparatively higher, albeit with lower detection frequencies. A negative correlation was established between organic contaminant levels and antioxidative capacity, suggesting a potential link between higher antioxidative potential and lower organic contaminant levels. Diagnostic ratio pointed towards traffic emissions as the primary source of the detected PAH. The presence of PAH suggests potential health risk, underscoring the need for further in-depth investigation.

Assessment of anthropogenic pollution in Guanabara Bay (SE Brazil) through biogeochemical data and stable isotope mixing models.

This work intends to identify pollution sources along the margins of Guanabara Bay (GB; SE Brazil) through a multiproxy approach and Bayesian stable isotopic mixture model (BSIMM). For this purpose, 33 surface sediment samples were collected and analyzed for granulometry, geochemistry (heavy metals, total organic carbon-TOC, stable isotopes of carbon and nitrogen-δ13C and δ15N, Rock-Eval pyrolysis parameters-REPP), and physicochemical parameters. Metal concentrations (E) dissolved in water (EW), adsorbed by organic matter (EOM) and by Mn hydroxides (EMn), and total extracted concentrations (ET) were analyzed. Sampling was conducted in 2018 after an oil spill from Reduc Oil Refinery. Potential Ecological risk index (PERI), based on metals, classified 85% of the analyzed stations as having moderate to considerable ecological risk. The metals with the potential to cause the highest ecological risk were CdW, CdOM, PbOM, and HgOM. The combination of BSIMM and REPP data was an effective proxy for oil spill detection by indicating the presence of polycyclic aromatic hydrocarbons (PAHs). Relatively high TOC contents suggested that the analyzed stations are eutrophicated environments. BSIMM discriminated three groups of stations with different sources of organic matter (OM), endorsing the result previously shown by the cluster analysis: (A) Niterói region, Botafogo marina, Glória marina, Fiscal and Fundão islands with diffuse sources of OM, including marine phytoplankton and material of continental origin from highly polluted rivers and domestic sewage; (B) region near Fundão and Governador islands and Mangue Channel outlet with OM (≃70%) supplied by highly polluted streams and a small contribution of PAHs; (C) Duque de Caxias and Botafogo-Urca inlet with significant contributions of PAHs, materials from C-3 plants and rivers polluted by urban sewage. Results of linear regressions in conjunction with BSIMM indicate that HgMn and PbOM mainly affect Group A's stations. Although the eastern margin of GB (Niterói; Group A) showed greater oceanic interaction than the other groups, it presented substantial concentrations of metals, potentially harmful (i.e., Hg and Pb) to marine biota and human health.

Investigation of organic micropollutant pollution in İzmit Bay: a comparative study of passive sampling and instantaneous sampling techniques.

In this study, we used a comprehensive array of sampling techniques to examine the pollution caused by organic micropollutants in İzmit Bay for the first time. Our methodology contains spot seawater sampling, semi-permeable membrane devices (SPMDs) passive samplers for time-weighted average (TWA), and sediment sampling for long-term pollution detection in İzmit Bay, together. Additionally, the analysis results obtained with these three sampling methods were compared in this study. Over the course of two seasons in 2020 and 2021, we deployed SPMDs for 21days in the first season and for 30days in the second season. This innovative approach allowed us to gather sea water samples and analyze them for the presence of polycyclic aromatic hydrocarbons (Σ15 PAHs), polychlorinated biphenyls (Σ7 PCBs), and organochlorine pesticides (Σ11 OCPs). Using SPMD-based passive sampling, we measured micropollutant concentrations: PAHs ranged from 1963 to 10342pg/L in 2020 and 1338 to 6373pg/L in 2021; PCBs from 17.46 to 61.90pg/L in 2020 and 8.37 to 78.10pg/L in 2021; and OCPs from 269.2 to 8868pg/L in 2020 and 141.7 to 1662pg/L in 2021. Our findings revealed parallels between the concentrations of PAHs, PCBs, and OCPs in both SPMDs and sediment samples, providing insights into the distribution patterns of these pollutants in the marine ecosystem. However, it is worth noting that due to limited data acquisition, the suitability of spot sampling in comparison to instantaneous sampling remains inconclusive, highlighting the need for further investigation and data collection.

PM2.5-bound polycyclic aromatic hydrocarbons (PAHs): quantification and source prediction studies in the ambient air of automobile workshop using the molecular diagnostic ratio

The presence of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere has been linked to health concerns, including cancer. Automobile workshops are significant contributors to PAH emissions due to their operations. Hence, this investigation aimed to identify and quantify the sources of PM2.5-bound PAHs in the ambient air of automobile workshops in Benin City, Nigeria, using molecular diagnostic ratios. PM2.5 samples were collected from 60 automobiles over 1 year, during the rainy (April to November) and dry (December to March) seasons of 2019. Sample collection utilized a low-volume air sampler with quartz filter paper, and extraction was performed using a 1:1 mixture of acetone and dichloromethane. The analysis involved an HP Agilent Technology 6890 Gas Chromatography (GC) system with a flame ionization detector. The annual average concentrations of PM2.5-bound PAHs in Benin City were 269.87 ± 249.32 ng/m3 (dry season) and 216.30 ± 204.89 ng/m3 (wet season). Molecular diagnostic ratios, such as Fl/(Fl + Py), An/(An + Phe), BaP/(BaP + Chry), BbF/BkF, InP/(InP + BghiP), and BaA/(BaA + Chr), aided in identifying PAH sources. Gasoline combustion, diesel combustion, traffic emissions, and emissions from automobile panel welders were found to be the primary sources of PAHs near vehicle workshops. These findings provide crucial insights for developing effective strategies to reduce emissions and protect public health in the air surrounding automobile workshops in Benin City.

Mixing temperature optimization and modification mechanism of medical masks modified asphalt: Insights from computational chemistry

Masks modified asphalt (MMA) offers a solution to pollution caused by discarded medical masks. Mixing temperature plays a crucial role in storage stability and even rheological performance of MMA. Traditional selection method overly relies on trial-and-error experiment, neglecting the convenience offered by computational chemistry. Furthermore, previous literature lacks precise elucidation of MMA’s physical modification mechanism, especially concerning the binding mode and energy composition. To address these issues, the optimal mixing temperature for MMA was recommended based on molecular dynamics. The rationality of recommended temperature was validated through laboratory tests, simultaneously investigating the impact of heating time. Fluorescence microscopy and multi-band spectroscopy were employed to acquire the microstructure. Binding modes in MMA were determined using binding sites exploration, evaluating the energy composition of each binding mode through quantum chemistry. The interaction mechanism was explained based on surface properties of isolated molecules. Results indicated that 170℃ was the recommended optimal mixing temperature derived from mixing free energy and Flory-Huggins interaction parameter. The fluctuations in softening point difference (ΔTR&B) and separation ratio (RS) concurrently tended towards stability, thereby validating the reliability of recommended temperature. Moreover, even after 72 h heating, MMA prepared at recommended temperature remained within a reasonable range concerning ΔTR&B, RS, and microscopic structure. Perpendicular, parallel, toroidal, and spherical modes emerged in MMA. Perpendicular and parallel modes exhibited the highest binding energies, while circular mode demonstrated the lowest. Binding energy is primarily governed by van der Waals interaction, attributed to the dominance of dispersion term on MMA’s molecular surface. Besides, due to the presence of polycyclic aromatic hydrocarbons in asphalt molecules, electrostatic interaction contributed to specific molecular bindings.

A multi-omics approach to unravelling the coupling mechanism of nitrogen metabolism and phenanthrene biodegradation in soil amended with biochar

The presence of polycyclic aromatic hydrocarbons (PAHs) in soil negatively affects the environment and the degradation of these contaminants is influenced by nitrogen metabolism. However, the mechanisms underlying the interrelationships between the functional genes involved in nitrogen metabolism and phenanthrene (PHE) biodegradation, as well as the effects of biochar on these mechanisms, require further study. Therefore, this study utilised metabolomic and metagenomic analysis to investigate primary nitrogen processes, associated functional soil enzymes and functional genes, and differential soil metabolites in PHE-contaminated soil with and without biochar amendment over a 45-day incubation period. Results showed that dissimilatory nitrate reduction to ammonium (DNRA) and denitrification were the dominant nitrogen metabolism processes in PHE-contaminated soil. The addition of biochar enhanced nitrogen modules, exhibiting discernible temporal fluctuations in denitrification and DNRA proportions. Co-occurrence networks and correlation heatmap analysis revealed potential interactions among functional genes and enzymes responsible for PHE biodegradation and nitrogen metabolism. Notably, enzymes associated with denitrification and DNRA displayed significant positive correlation with enzymes involved in downstream phenanthrene degradation. Of particular interest was stronger correlation observed with the addition of biochar. However, biochar amendment inhibited the 9-phenanthrol degradation pathway, resulting in elevated levels of glutathione (GSH) in response to environmental stress. These findings provide new insights into the interactions between nitrogen metabolism and PHE biodegradation in soil and highlight the dual effects of biochar on these processes.

New insights into the Ferrate-Sulfite system for the degradation of polycyclic aromatic Hydrocarbons: A dual role for sulfite

The presence of polycyclic aromatic hydrocarbons (PAHs) in water is a significant environmental concern due to their potential health risks. While sulfite activation of ferrate (Fe(VI)) has shown promise in enhancing the degradation of antibiotics and pesticides in water systems, its applicability to the degradation of PAHs remains largely unexplored. Here, we investigated the efficiency and mechanisms of PAH degradation via sulfite-activated ferrate. The ferrate-sulfite system significantly accelerated PAH degradation, achieving a 1.53 to 3.13-fold rate increase compared to ferrate-only treatment. Key active species involved in PAHs degradation were Fe(V), Fe(IV), and SO4●−. Sulfite accelerated the degradation of PAHs by undergoing a swift reaction with Fe(VI), leading to the formation of Fe(V) and SO4●−. Sulfite accelerated the degradation of PAHs by undergoing a swift reaction with Fe(VI) resulting in the production of Fe(V) and SO4●−. Through the reduction of ferrate species by sulfite, Fe(III) were produced and accelerated the decomposition of residual Fe(VI) into Fe(IV). Sulfite accelerates the degradation of PAHs by ferrate through these two processes. It promotes Fe(V) and Fe(IV) production from ferrate in a different way. Importantly, the toxicity of PAHs degradation intermediates is significantly reduced. Overall, these findings indicate that the ferrate-sulfite combination has significant potential to address environmental and health concerns associated with PAHs in water sources.

Polycyclic aromatic hydrocarbons concentration and spatial distribution in the soils of Santiago de Compostela (northwestern Spain)

Organic pollutants are commonly accumulated in urban soils, interfering with the normal functions of soils and ecosystems, and representing potential risks for human health and well-being. Here we have studied the presence of polycyclic aromatic hydrocarbons (PAHs) in 55 soils from the city of Santiago de Compostela (Spain). The soils include different land uses: urban grasslands, urban forests, urban and periurban agricultural soils. Sample preparation was carried out by miniaturized ultrasound-assisted extraction and analytical determination was performed by gas chromatography-tandem mass spectrometry. Results revealed the presence in the soils of 17 out of the 18 PAHs analyzed, with total concentration levels up to μg g−1 in 28% of the analyzed soils. The sum of their concentrations varied widely, between 4 and 4728 ng g−1, with a mean value of 508 ng g−1 (median 217 ng g−1). The sum of the 16 EPA PAHs ranged from 4 to 4216 ng g−1, with a median of 193 ng g−1. The values found are similar to other similar-sized cities with low population densities. The study of PAHs distribution with depth in one soil showed that these compounds are mainly concentrated in the top 20 cm. Spatial distribution was very heterogeneous and without a clear pattern. In general, all PAHs were strongly intercorrelated except naphthalene, whereas no correlations have been found to soil physicochemical properties. Strong correlation of PAHs with Pb was observed, suggesting a common major source for these pollutants, probably combustion by traffic and households.

Growing of 2D/3D graphene structures on natural substrates from aromatic plastic wastes by scalable thermal-based upcycling process with a comparative CO2 footprint analysis

Recycling aromatic plastics, such as polystyrene (PS) and polyethylene terephthalate (PET), is complex and strongly sensitive to the process design and conditions due to the presence of polycyclic aromatic hydrocarbons and interunit CO and/or CC linkages. Herein, the upcycling process becomes crucial to attain high-value-added products from aromatic plastics. With this study, graphene growth was achieved on the natural substrates of talc and organically modified montmorillonite (OMMT), from waste PS and PET sources via a sustainable, affordable, and environment-friendly upcycling technique. This promising method promotes the formation of 2D and 3D graphene structures from waste PS and PET. This provides dimension-controlled graphene growth by tailoring the substrate type and size, surface composition of the substrate, and the degree of aromaticity in the polymer. In addition, polymer processing techniques of twin-screw extrusion and thermokinetic mixing, were investigated in the development of graphene-grown hybrid additives to tailor the degree of crystallinity. Regarding structural characterization results, a high shear rate mixer led to the change in crystalline planes of talc, whereas conventional twin screw extrusion preserved the structure of talc indicating that high shear rate triggered the exfoliation of talc. Furthermore, a systematic life cycle assessment was conducted to evaluate the CO2 footprint of upcycled graphenes grown on talc and OMMT compared to graphene produced from graphite. Upcycled graphene structures obtained by direct carbonization and even catalyst impregnated natural substrate-based graphene growth process with PS or PET source have comparably lower CO2 emission than graphene received from graphite. Therefore, these newly developed and upcycled hybrid additives opens a way for the conversion of aromatic complex plastic wastes into value-added nanomaterials being candidate as reinforcing agent by adopting a circular economy model.

The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry

In this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hydrocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical challenge to analytical chemists. To address this issue we optimized and validated a novel extraction protocol including cryogenic homogenization, liquid-liquid extraction and further preconcentration by evaporation. By using deuterated internal standards in conjunction with matrix-matched calibration, high precision and accuracy were achieved. The limit of detection is estimated in the range of 0.041–0.221 ng/g (for fluorene and fluoranthene, respectively), which is far below the concentration currently assumed to be dangerous for children. The method was successfully applied to real samples available on the Polish market, and it was found that the amount of PAH compounds varies between manufacturers. Most diapers do not have all 15 polycyclic aromatic hydrocarbons in their composition, but there is no diaper that is free of these compounds. The most abundant in diapers was acenaphthalene, where the concentration ranged from 1.6 ng/g diaper up to 362.4 ng/g. The lowest concentration in diapers is chrysene, which is not detected in most diapers. The article is a response to the lack of a harmonized analytical method for the determination of polycyclic aromatic hydrocarbons in disposable sanitary products for children.

The presence of polycyclic aromatic hydrocarbons (PAHs) in air particles and estimation of the respiratory deposition flux

Polycyclic aromatic hydrocarbons (PAHs) in the atmospheric particles constitute a topic of growing health concern. This study aims to calculate PAH concentrations, identify the source, assess the health risk from exposure to carcinogenic PAHs, and the respiratory deposition flux. PM10 and PM2.5 were collected in September 2019 in the urban, semi-urban, and semi-urban-industrial areas of Kuala Lumpur, Batu Pahat, and Bukit Rambai, respectively. A total of 18 PAHs from PM10 and 17 PAHs from PM2.5 were extracted using dichloromethane and determined using gas chromatography coupled with a flame ionization detector (GC-FID). The health risk assessment (HRA) calculated included B[a]P equivalent (B[a]Peq), lifetime lung cancer risk (LLCR), incremental lifetime cancer risk (ILCR), and respiratory deposition dose (RDD). The results show PAHs in PM10 recorded in Kuala Lumpur (DBKL), Batu Pahat (UTHM), and Bukit Rambai are 9.91, 8.45, and 9.57 ng/m3, respectively. The average PAHs in PM2.5 at the three sampling sites are 11.65, 9.68, and 9.37 ng/m3, respectively. The major source of PAHs obtained from the DRs indicates pyrogenic activities for both particle sizes. For PM10, the total B[a]Peq in DBKL, UTHM, and Bukit Rambai were 1.97, 1.82, and 2.32 ng/m3, respectively. For PM2.5 samples, the total B[a]Peq in DBKL, UTHM, and Bukit Rambai were 2.80, 2.33, and 2.57 ng/m3, respectively. The LLCR and ILCR show low to moderate risk for all age groups. The RDD of adults and adolescents is highest in both PM10 and PM2.5, followed by children, toddlers, and infants. Overall, we perceive that adults and adolescents living in the urban area of Kuala Lumpur are at the highest risk for respiratory health problems because of prolonged exposure to PAHs in PM10 and PM2.5, followed by children, toddlers, and infants.

Study of the long-finned pilot whale (Globicephala melas) bile content - An indicator of ocean health

Globicephala melas has been harvested in the Faroe Islands for centuries. Given the distances travelled by this species, tissue/body fluid samples represent unique matrices to be considered as an integration of environmental condition and pollution status of their prey. For the first time, bile samples were analysed for presence of polycyclic aromatic hydrocarbon (PAH) metabolites and protein content. Concentrations of 2- and 3-ring PAH metabolites ranged from 11 to 25 μg mL−1 pyrene fluorescence equivalents. In total, 658 proteins were identified and 61,5 % were common amongst all individuals. Identified proteins were integrated into in silico software and determined that the top predicted disease and functions were neurological diseases, inflammation, and immunological disorders. The metabolism of reactive oxygen species (ROS) was predicted to be dysregulated, which can have consequences to both the protection against ROS produced during dives and contaminant exposures. The obtained data is valuable for understanding metabolism and physiology of G. melas.