Pyrene Concentration Research Articles

Homology Modeling of Laccase Enzyme of Filamentous Fungus Trichoderma sp. CNSC-2 and Its Role in Pyrene Degradation

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants that impart several hazardous effects on the environment. Extracellular enzymes released by filamentous fungi are well-known participants in the degradation of such organic pollutants. The present study aims to determine the interaction of pyrene with Lac1 protein, coding for the extracellular laccase enzyme from Trichoderma sp. CNSC-2. Lac1 sequence analysis revealed the stable and acidic nature of the laccase enzyme. The dominance of random coils (54.8%) and extended strands (28.3%) in secondary structure defined protein flexibility. 3D homology modeling followed by validation revealed a high-quality model with 94.8% residues in the favored zone of Ramachandran plot. Molecular docking study with pyrene displayed a significant binding affinity of −7.82 kcal mol−1 with the amino acid residues at the active binding site of Lac1, indicating a strong role in pyrene binding. Trichoderma sp. CNSC-2 achieved 69.42 ± 0.4% of pyrene removal efficiency at 100 mg l−1 pyrene concentration on day 12 of incubation. Laccase activity during pyrene degradation simultaneously increased, and the highest activity was observed on day 6 of incubation. Enzyme production was found to be optimum at pH 6 (p < 0.001) and 30°C temperature (p < 0.0001). FTIR analysis showed deviation in the amide bands of laccase in the presence of pyrene, and additional peaks coinciding with pyrene metabolites were observed. The decrease in intensity of laccase due to quenching by pyrene interaction was determined by fluorescence spectroscopy. Thus, this study suggested a strong binding affinity of pyrene to the laccase active site implying the potential role of laccase enzyme from Trichoderma sp. CNSC-2 in pyrene degradation.

Assessing the Combined Pollution and Risks of Potentially Toxic Elements and PAHs in the Urban Soils of the Oldest City in Western Siberia: A Case Study of Tyumen, Russia

Ensuring the sustainability of modern cities is based on creating comfortable living conditions, including reducing negative environmental impacts. The effects of various types of anthropogenic activity are manifested in a particular decrease in the quality of soils. This study aimed to assess the co-contamination of urban topsoils in Tyumen, Russia, with potentially toxic elements (PTEs), priority polycyclic aromatic hydrocarbons (PAHs), and the associated ecological and health risks. A set of 241 soil samples were analyzed using X-ray fluorescence and high-performance liquid chromatography to identify PTEs and PAHs, respectively. The most hazardous substances were Ni, As, Pb, naphthalene (NAP), fluoranthene, and high-molecular-weight PAHs causing low-to-very-high individual pollution. In general, the contribution of PAHs to soil pollution was higher than that of PTEs. It was found that 96% of the samples could be classified as clean according to the total pollution index (Zc), widely used in Russia. At the same time, one-third of the samples were characterized by low-to-high contamination according to the Nemerov pollution index (NPI). Thus, the NPI was more informative for estimating total soil pollution than the Zc. The As, Pb, NAP, and benzo[a]pyrene (BaP) contents exceeded the maximum permissible concentrations in soils by an order of magnitude, reaching an extremely dangerous level. However, the average ecological risk was assessed as minimal. Non-carcinogenic risks were predominantly due to PTE exposure and were moderate for children and low for adults. Throughout the city, carcinogenic risks exceeded the threshold but generally corresponded to a low level. The main source of carcinogenic risk was exposure to Co, As, and Pb. In general, the quality of Tyumen soils in terms of the content of PTEs and PAHs can be described as satisfactory. A spatial analysis of soil pollution and associated risks identified hot spots requiring further monitoring.

Macromolecular Conformation of Low-Generation PAMAM Dendrimers Probed by Pyrene Excimer Formation

A series of pyrene-labeled PAMAM dendrimers (PyCX-PAMAM-GY, where X (=4, 8, or 12) and Y (=0, 1, or 2) represent the number of atoms in the pyrenyl linker and the dendrimer generation, respectively) were studied by acquiring their time-resolved fluorescence decays in N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The fluorescence decays were fitted globally according to the model-free analysis (MFA), which yielded the average rate constant ⟨k⟩ for pyrene excimer formation (PEF). ⟨k⟩ was compared with the local pyrene concentration [Py]loc inside the dendrimers, which was calculated by assuming that the segments constituting the dendrimer interior obey Gaussian statistics. ⟨k⟩ was found to increase linearly with [Py]loc in both solvents, but the straight lines had different slopes due to differences in solvent viscosity and polarity. These differences were accounted for by dividing ⟨k⟩ by kdiff, which is the bimolecular rate constant for PEF generated by n-hexyl-1-pyrenebutyramide used as a model compound. The ⟨k⟩/kdiff ratios obtained for all the PyCX-PAMAM-GY samples in DMF and DMSO collapsed onto a single master line where ⟨k⟩/kdiff increased linearly with [Py]loc. The strong correlation found between ⟨k⟩ and [Py]loc suggested that the oligomeric segments constituting the interior of the low-generation (Y = 0, 1, and 2) PAMAM dendrimers obeyed Gaussian statistics. This fact was further supported by using the Gaussian approximation to calculate the radius of gyration (Rg) of PAMAM dendrimers and compare them to the Rg values obtained by molecular dynamics simulations. The excellent agreement obtained between the two sets of Rg values validated the assumption. Furthermore, the direct relationship between ⟨k⟩ and [Py]loc established in this study demonstrates that ⟨k⟩ provides a quantitative measure of the internal density of the dendrimers, an observation with considerable implications for the quantitative conformational characterization of macromolecules with a complex architecture in solution.

Persistence Length and Encounter Frequency Determination from Fluorescence Studies of Pyrene-Labeled Poly(oligo(ethylene glycol) methyl ether methacrylate)s

A series of nine pyrene-labeled poly(oligo(ethylene glycol) methyl ether methacrylate)s (Py-PEGnMAs) with n equal to 0–5, 9, 16, and 19 were prepared by random radical copolymerization of 1-pyrenebutyl methacrylate and nine different EGnMA monomers. The process of pyrene excimer formation (PEF) in the Py-PEGnMA samples was characterized in acetone, THF, toluene, N,N-dimethylformamide (DMF), dioxane, and dimethyl sulfoxide (DMSO). The fluorescence decays of all Py-PEGnMA samples were acquired in the six solvents and analyzed with the fluorescence blob model (FBM) to yield the number Nblob of structural units (SU) in the subvolume of the polymer coil probed by an excited pyrene and referred to as a blob, and the rate constant kblob describing the encounters between two SU bearing an excited and a ground-state pyrenyl label located inside a same blob. Nblob and kblob remained constant with pyrene content for a same series of Py-PEGnMA samples. After averaging Nblob and kblob over all pyrene contents for a same Py-PEGnMA series, ⟨Nblob⟩ and the product ⟨kblob × Nblob⟩ were found to decrease with increasing side chain length reflecting a progressive stiffening and decrease in the internal dynamics of the polymethacrylate backbone, respectively. ⟨Nblob⟩ and ⟨kblob × Nblob⟩ could be parametrized as a function of the molecular weight of an SU and the solvent viscosity. The parametrized form of ⟨Nblob⟩ was applied to determine the persistence length (lp) of the PEGnMA samples using the Kratky–Porod equation. lp was found to increase linearly with the square of the side chain length of the PEGnMA samples, as expected theoretically. The parametrized form of ⟨kblob × Nblob⟩ was used as a calibration curve against which the internal dynamics of several polypeptides and poly(methyl acrylate) could be compared in DMSO. This study illustrates the ability of PEF measurements to determine the persistence length and quantify the internal dynamics of polymers in solution, two important parameters in the characterization of macromolecules.

Different sorption behaviours of pyrene onto polyethylene microplastics in a binary system with water and a ternary system with water and sediment

Microplastics (MPs) and polycyclic aromatic hydrocarbons (PAHs) are two ubiquitous coexisting pollutants that pose potential threats to the environment and organisms and have attracted increasing attention in recent years. However, the interaction between these two pollutants in water, with and without sediment, and the associated mechanisms have not been fully understood. This study aims to explore differences in the sorption behaviours of pyrene at environmentally realistic concentrations by polyethylene MPs (PE-MPs) in binary (water-MPs) and ternary (water-MPs-sediment) systems and to elucidate the role of sediment in the sorption process. Kinetic and isothermal studies show that sediment acted as a “sponge” to adsorb the vast majority of pyrene at the beginning of the sorption experiment in the ternary system, which behaved differently than in the binary system. The sediment-sorbed pyrene was then gradually released but re-adsorbed by PE-MPs, while the concentration of pyrene in water remained at a steady low level. These findings reveal that PE-MPs exhibited a higher pyrene affinity than sediment and being potential pyrene carriers in aqueous systems. Through sorption kinetics and isotherm models study, it was found that pseudo-second-order (PSO) kinetics (0.9773), Elovich (0.9314) and Henry’s (0.9850) models has the highest R2 value, indicating that chemisorption and hydrophobic interactions were attributed to the sorption process. The present study also demonstrates the competition between sediment and MPs in adsorption of pyrene, and highlights the impact of sediment and MPs in the partitioning of PAHs in aquatic environments, which may change the fate of pollution carried by MPs.

Heavy Metals and Hydrocarbon Level in Nile Tilapia (Oreochromis niloticus), Mullet Fish (Liza falcipinus) and Crab (Callinectes amnicola) from Crude Oil Contaminated Jetty Rivers in Port Harcourt, Nigeria

In this study, the level of polycyclic aromatic hydrocarbons and heavy metals (Pb, Cr, Zn, Cd, Cu, Fe and Mn) contamination were determined in Nile tilapia, Mullet fish and Crab collected from crude oil polluted rivers (Abuloma and Woji Jetty). Average individual PAHs concentration ranged from 0.0001mgkg-1 to 11.22±0.02mgkg-1 in Nile tilapia, 0.0001mgkg-1 to 13.43±0.17mgkg-1 in mullet fish and 0.0001mgkg-1 to 12.23±0.06mgkg-1 in crab. Benzo[a]pyrene (a carcinogenic PAH) concentrations detected in fish and seafood in this study exceeded the acceptable limit set by the European Commission (0.002mgkg-1) for fish considered safe for human consumption. The levels of Pb and Cr in fish and seafood were found to have remarkably higher concentrations which exceeded the acceptable levels (FAO/WHO) in food sources for human consumptionand that of Cd, Fe, Zn, Cu and Mn were lower. Results from this study revealed high levels of PAHs and heavy metals in seafood samples from all study locations. These high PAHs levels in these commonly consumed seafoods from the rivers question their safety for human consumption.

Potential of Coupling Metaheuristics-Optimized-XGBoost and SHAP in Revealing PAHs Environmental Fate.

Polycyclic aromatic hydrocarbons (PAHs) refer to a group of several hundred compounds, among which 16 are identified as priority pollutants, due to their adverse health effects, frequency of occurrence, and potential for human exposure. This study is focused on benzo(a)pyrene, being considered an indicator of exposure to a PAH carcinogenic mixture. For this purpose, we have applied the XGBoost model to a two-year database of pollutant concentrations and meteorological parameters, with the aim to identify the factors which were mostly associated with the observed benzo(a)pyrene concentrations and to describe types of environments that supported the interactions between benzo(a)pyrene and other polluting species. The pollutant data were collected at the energy industry center in Serbia, in the vicinity of coal mining areas and power stations, where the observed benzo(a)pyrene maximum concentration for a study period reached 43.7 ngm-3. The metaheuristics algorithm has been used to optimize the XGBoost hyperparameters, and the results have been compared to the results of XGBoost models tuned by eight other cutting-edge metaheuristics algorithms. The best-produced model was later on interpreted by applying Shapley Additive exPlanations (SHAP). As indicated by mean absolute SHAP values, the temperature at the surface, arsenic, PM10, and total nitrogen oxide (NOx) concentrations appear to be the major factors affecting benzo(a)pyrene concentrations and its environmental fate.

Benzo[a]pyrene stress impacts adaptive strategies and ecological functions of earthworm intestinal viromes

The earthworm gut virome influences the structure and function of the gut microbiome, which in turn influences worm health and ecological functions. However, despite its ecological and soil quality implications, it remains elusive how earthworm intestinal phages respond to different environmental stress, such as soil pollution. Here we used metagenomics and metatranscriptomics to investigate interactions between the worm intestinal phages and their bacteria under different benzo[a]pyrene (BaP) concentrations. Low-level BaP (0.1 mg kg−1) stress stimulated microbial metabolism (1.74-fold to control), and enhanced the antiphage defense system (n = 75) against infection (8 phage-host pairs). Low-level BaP exposure resulted in the highest proportion of lysogenic phages (88%), and prophages expressed auxiliary metabolic genes (AMGs) associated with nutrient transformation (e.g., amino acid metabolism). In contrast, high-level BaP exposure (200 mg kg−1) disrupted microbial metabolism and suppressed the antiphage systems (n = 29), leading to the increase in phage-bacterium association (37 phage-host pairs) and conversion of lysogenic to lytic phages (lysogenic ratio declined to 43%). Despite fluctuating phage-bacterium interactions, phage-encoded AMGs related to microbial antioxidant and pollutant degradation were enriched, apparently to alleviate pollution stress. Overall, these findings expand our knowledge of complex phage-bacterium interactions in pollution-stressed worm guts, and deepen our understanding of the ecological and evolutionary roles of phages.

The Ability of Airborne Microalgae and Cyanobacteria to Survive and Transfer the Carcinogenic Benzo(a)pyrene in Coastal Regions.

Air pollution has been a significant problem threatening human health for years. One commonly reported air pollutant is benzo(a)pyrene, a dangerous compound with carcinogenic properties. Values which exceed normative values for benzo(a)pyrene concentration in the air are often noted in many regions of the world. Studies on the worldwide spread of COVID-19 since 2020, as well as avian flu, measles, and SARS, have proven that viruses and bacteria are more dangerous to human health when they occur in polluted air. Regarding cyanobacteria and microalgae, little is known about their relationship with benzo(a)pyrene. The question is whether these microorganisms can pose a threat when present in poor quality air. We initially assessed whether cyanobacteria and microalgae isolated from the atmosphere are sensitive to changes in PAH concentrations and whether they can accumulate or degrade PAHs. The presence of B(a)P has significantly affected both the quantity of cyanobacteria and microalgae cells as well as their chlorophyll a (chl a) content and their ability to fluorescence. For many cyanobacteria and microalgae, an increase in cell numbers was observed after the addition of B(a)P. Therefore, even slight air pollution with benzo(a)pyrene is likely to facilitate the growth of airborne cyanobacteria and microalgae. The results provided an assessment of the organisms that are most susceptible to cellular stress following exposure to benzo(a)pyrene, as well as the potential consequences for the environment. Additionally, the results indicated that green algae have the greatest potential for degrading PAHs, making their use a promising bioremediation approach. Kirchneriella sp. demonstrated the highest average degradation of B(a)P, with the above-mentioned research indicating it can even degrade up to 80% of B(a)P. The other studied green algae exhibited a lower, yet still significant, B(a)P degradation rate exceeding 50% when compared to cyanobacteria and diatoms.

Changes in metabolic profiles of amphipods Allorchestes compressa after acute exposures to copper, pyrene, and their mixtures

Amphipods are ideal indicators for biomonitoring and ecotoxicological studies of environmental contaminants because they are extensively distributed in aquatic environments, are easy to collect and are important in nutrient cycling. Marine amphipods (Allorchestes compressa) were exposed to two concentrations of copper and pyrene, and their mixtures, for 24 and 48 h. Changes in polar metabolites were assessed using Gas Chromatography Mass Spectrometry (GC-MS)-based untargeted metabolomics. Generally, limited metabolite changes were observed for copper and pyrene single exposures (eight and two significant metabolites, respectively), while 28 metabolites had changed following exposures to mixtures. Furthermore, changes were mainly observed after 24 h but had seemingly returned to control levels after 48 h. Multiple types of metabolites were affected including amino acids, Tricarboxylic acid (TCA) cycle intermediates, sugars, fatty acids, and hormones. This study highlights the sensitivity of metabolomics in assessing the impacts of low concentrations of chemicals compared to traditional ecotoxicological endpoints.

Pyrene‐Based Covalent Organic Frameworks for Photocatalytic Hydrogen Peroxide Production

AbstractFour highly porous covalent organic frameworks (COFs) containing pyrene units were prepared and explored for photocatalytic H2O2 production. The experimental studies are complemented by density functional theory calculations, proving that the pyrene unit is more active for H2O2 production than the bipyridine and (diarylamino)benzene units reported previously. H2O2 decomposition experiments verified that the distribution of pyrene units over a large surface area of COFs plays an important role in catalytic performance. The Py‐Py‐COF though contains more pyrene units than other COFs which induces a high H2O2 decomposition due to a dense concentration of pyrene in close proximity over a limited surface area. Therefore, a two‐phase reaction system (water‐benzyl alcohol) was employed to inhibit H2O2 decomposition. This is the first report on applying pyrene‐based COFs in a two‐phase system for photocatalytic H2O2 generation.

Pyrene-Based Covalent Organic Frameworks for Photocatalytic Hydrogen Peroxide Production.

Four highly porous covalent organic frameworks (COFs) containing pyrene units were prepared and explored for photocatalytic H2 O2 production. The experimental studies are complemented by density functional theory calculations, proving that the pyrene unit is more active for H2 O2 production than the bipyridine and (diarylamino)benzene units reported previously. H2 O2 decomposition experiments verified that the distribution of pyrene units over a large surface area of COFs plays an important role in catalytic performance. The Py-Py-COF though contains more pyrene units than other COFs which induces a high H2 O2 decomposition due to a dense concentration of pyrene in close proximity over a limited surface area. Therefore, a two-phase reaction system (water-benzyl alcohol) was employed to inhibit H2 O2 decomposition. This is the first report on applying pyrene-based COFs in a two-phase system for photocatalytic H2 O2 generation.

Dual Function of 4-Aminothiophene in Surface-Enhanced Raman Scattering Application as an Internal Standard and Adsorbent for Controlling Au Nanocrystal Morphology.

The sensitivity and quantitative accuracy of surface-enhanced Raman scattering (SERS) are the main factors that restrict its application. Here, novel Au nanoscale convex polyhedrons (Au NCPs) were designed and fabricated to solve these problems via an embedded standard, including eight pods and six small protrusions. Spherical Au seeds regrew into different sizes of Au NCPs with a face-centered cubic structure. This morphology is due to the dual mechanism of the 4-aminothiophene (4-ATP) molecule that serves as an internal standard and a surface ligand regulator combined with the regulatory role of hexadecyl trimethyl ammonium chloride. The results show that Au NCPs were enclosed by high-index {12 9 1} facets, which greatly improved the local plasma resonance and reduced the lowest SERS detectable concentration of pyrene in standard seawater to 0.5 nM. An effective reference was produced by embedding 4-ATP with a relative standard deviation value less than 2.97% (in the same batch) and 3.92% (between different batches). Our research offers a new strategy for morphological regulation of metal nanocrystals, which is useful for the preparation of highly sensitive SERS substrates and trace analysis.

Modelling benzo(a)pyrene concentrations for different meteorological conditions – Analysis of lung cancer cases and associated economic costs

Air pollution originating from the household presents a significant burden to public health, especially during the wintertime in countries, such as Poland, where coal substantially contributes to the energy market. One of the most hazardous components of particulate matter is benzo(a)pyrene (BaP). This study focusses on the impact of different meteorological conditions on BaP concentrations in Poland and associated impacts on human health and economic burdens. For this study, we used the EMEP MSC-W atmospheric chemistry transport model with meteorological data from the Weather Research and Forecasting model to analyze the spatial and temporal distribution of BaP over Central Europe. The model setup has two nested domains, with the inner domain at 4 km × 4 km over Poland, which is a hotspot for BaP concentrations. The outer domain covers countries surrounding Poland in coarser resolution (12 × 812 km), to ensure that transboundary pollution is properly characterized in the modelling. We investigated the sensitivity to variability in winter meteorological conditions on BaP levels and impacts using data from 3 years: 1) 2018, which represents average meteorological conditions during the winter season (BASE run), 2) 2010 with a cold winter (COLD), and 3) 2020 with a warm winter (WARM). The ALPHA-RiskPoll model was used to analyze the lung cancer cases and associated economic costs. The results show that the majority of Poland exceeds the target level of benzo(a)pyrene (1 ng m−3) mainly due to high concentrations during the cold months. High concentrations of BaP have serious health implications and the number of lung cancers in Poland due to BaP exposure varies from 57 to 77 cases for the WARM and COLD years, respectively. It is reflected in the economic costs, which ranged from 136, through 174 to 185 million euros/year for the WARM, BASE and COLD model runs, respectively.

Simultaneous removal of sediment and water contaminants in a microbial electrochemical system with embedded active electrode by in-situ utilization of electrons.

In the water environment such as lakes, there is a phenomenon that the sediment and overlying water are polluted at the same time. In this study, A microbial electrochemical system with an embedded active electrode was developed for simultaneous removal of polycyclic aromatic hydrocarbons in sediment and antibiotics in overlying water by in-situ utilization of electrons. In the closed-circuit group, the pyrene concentration in sediment decreased from 9.94 to 2.08mg/L in 96 d, and the sulfamethoxazole concentration in water decreased from 5.12 to 1.12mg/L in 168h. These values were 18.71 % and 31.21 % higher, respectively, than those of the open-circuit group. The pyrene degradation pathway may be from polycyclic aromatic substances to low-cyclic aromatic hydrocarbons via successive breakdown of benzene rings. Multiple metabolites produced by reduction verified that SMX or its intermediates were reductively degraded in water. On the active electrode, the relative abundances of Acetobacterium and Piscinibacter, which were genera related to SMX degradation, was promoted, while the electricity-producing genus Pseudomonas was inhibited. ccdA, pksS, torC, and acsE genes related to extracellular electron transport may accelerate electron transport. Electrons could be transferred to SMX under the influence of proteins involved in extracellular electron transport, and SMX could be degraded reductively as an electron acceptor by microbes. Generation of electrons and in-situ utilization for simultaneous removal of solid-liquid two-phase pollutants will provide mechanistic insight into pollutant biodegradation by microbial electrochemistry and promote the development of sustainable bioremediation strategies for surface water.

Differences in structure and composition of soil humic substances and their binding for polycyclic aromatic hydrocarbons in different climatic zones

Humic substances (HSs) play important roles in the transport and bioavailability of hydrophobic organic compounds (HOCs) in soils. The sorption of HOCs depends on the compositions and structures of HSs which may differ in different climatic zones, however, the sorption behavior of HOCs by HSs in soils from different climatic zones is poorly understood. In this study, different HS fractions (humic acids-HAs, fulvic acids-FAs and humin-HM) in soils from different climatic zones were extracted and used as sorbents for polycyclic aromatic hydrocarbons (PAHs). The results indicated that HSs (including HA, FA and HM fractions) from colder climatic zones contained more oxygen-containing functional groups and exhibited smaller molecular weight as well as higher aliphaticity and polarity than those from warmer climatic zones. The sorption affinity of HAs at the low given concentration (0.05 Sw) of naphthalene (Nap), phenanthrene (Phe), pyrene (Pyr) and benz(α)anthracene (BaA) from warmer climatic zones to colder ones increased from 26.3 to 43.9, from 36.7 to 114.0, from 125.8 to 388.8, and from 322.5 to 876.1, respectively, and the same trends were obtained for FAs and HM at the same PAH concentration. The results indicated that HSs from colder climatic zones showed higher sorption affinity than those from warmer climatic zones. Moreover, the weighted contributions of FAs, HAs and HM to the overall sorption from different climatic zones were 9.1–28.4%, 13.5–59.2% and 23.4–76.9%, respectively. This indicates FA fraction, a previously neglected component, is also an important contributor to binding PAHs in soils. This study suggests that the difference in sorption behaviors of HOCs to HSs among different climatic zones should be considered when predicting HOC fates and bioavailability in soils.

Immune and neurohumoral profile of the children population living in the conditions of exposure to benzo(a)pyrene

Introduction. Benzo(a)pyrene induces disorders of immune and neurohumoral regulation that are aggravated by the influence of unfavourable climatic and geographical factors in the Far North. In this regard, studies of the features of the immune and neurohumoral profile are of particular relevance for the identification of markers of early health disorders of the population of industrially developed circumpolar territories (using the example of benzo(a)pyrene). Materials and methods. Five hundred 3-6 year children living in the circumpolar territory of Eastern Siberia were examined. Observation group consisted of 352 children living in conditions of exposure to benzo(a)pyrene. Comparison group included 148 children residing at a relatively clean territory. Determination of the content of benzo(a)pyrene in the blood was carried out by HPLC. Phenotyping of CD3+-, CD19+-, CD3+CD95+-, Annexin V-FITC+7AAD- and Annexin V-FITC+7AAD+-lymphocytes was performed by flow cytofluorometry. The level of IgA, IgM, IgG was determined by Mancini radial immunodiffusion, the IgG content to benzo(a)pyrene was determined by allergosorbent testing. The content of acetylcholine, serotonin, and neurotropin-3 was determined by ELISA. Results. Children living in the industrially developed circumpolar territory of Eastern Siberia have an increased level of blood contamination with benzo(a)pyrene (p&lt;0.05). The immune profile is characterized by inhibition of cellular (CD3+ deficiency) and humoral immunity (decreased IgA, IgM, IgG with an excess of CD19+). Violations of apoptosis (decrease in Annexin V-FITC+7AAD-, Annexin V-FITC+7AAD+-lymphocytes; increase in Bcl-2 and CD95+) were revealed (p&lt;0.05). An increased IgG to benz(a)pyrene content were found (p&lt;0.05). The neurohumoral profile of the examined children is characterized by hyperexpression of serotonin with acetylcholine and neurotropin-3 deficiency (p&lt;0.05). Limitations. The results of the study are intended for specialists in the field of hygiene, immunology and allergology. Conclusion. Revealed features of the immune status (deficiency of CD3+, Annexin V-FITC+7AAD-, and Annexin V-FITC+7AAD+-lymphocytes IgA, IgM, IgG, excess CD19+, CD95+, Bcl-2, IgG to benzo(a)pyrene), associated with changes in sympathetic-parasympathetic balance (excess serotonin, deficiency of acetylcholine, neurotropin-3) characterize the features of the immune and neurohumoral profile in the children population of the circumpolar territories of Eastern Siberia under the conditions of exposure to benzo(a)pyrene.

Contamination and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Seasoning Flour Products in Hunan, China.

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants with carcinogenic, teratogenic, and mutagenic effects. Dietary intake is one of the significant exposure pathways of PAHs. In this study, gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) was used to detect 16 priority PAHs listed by the United States Environmental Protection Agency (USEPA) in seasoning flour products distributed in Hunan Province. The consumption of seasoning flour products by the Hunan population was investigated by questionnaire. The results showed that the detection rate of PAHs in seasoning flour products in Hunan Province was 92.41%. Among them, benzo[a]anthracene (BaA), phenanthrene (PHE), fluoranthene (FLA), and chrysene (CHR) were dominant. The total PAHs and benzo[a]pyrene (BaP) contents of soggy seasoning flour product samples were higher than those of crisp samples and chewy samples. The total amount of PAHs in rod-shaped and flaky samples were higher than that in filamentous and granular samples. The margin of exposure (MOE) values of various seasoning flour products and all age groups (children, adolescents, and adults) was much more significant than 10,000. Moreover, the incremental lifetime of cancer risk (ILCR) values of all age groups were below 1 × 10-5. The above results indicate that PAHs in seasoning flour products have a relatively low health risk for the Hunan population. Still, it is recommended that susceptible populations (children, adolescents, etc.) should control their intake of flour products.

Biodegradation of organic compounds in the coal gangue by Bacillus sp. into humic acid.

Coal gangue (CG), one of the world's largest industrial solid wastes produced during coal mining, is extremely difficult to be used owing to its combined contents of clay minerals and organic macromolecules. This study explored a novel process of degrading the harmful organic compounds in the CG into humic acid using a biological method characterized by scanning electron microscope-energy dispersive spectrometer, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and elemental analyzer. The results reveal that adding selected Bacillus sp. to the CG for 40 days can increase the humic acid content by ~ 17 times, reaching 17338.17mg/kg, which is also the best level for promoting plant growth. FTIR and XPS spectra show that the organic compounds in the CG transforms primarily from C=C to C=O, COOH, and O-H groups, indicating that the organic compounds are gradually oxidized and activated, improving the humic acid concentration of soil. In addition, Bacillus sp. decreases pH and benzo[a]pyrene contents, and increases the content of available nutrients. After microbial degradation, coal gangue can be turned into ecological restoration materials.

Benz(a)pyrene content in soil and medicinal plants of Perm Krai (Russian Federation)

Benz(a)pyrene content in soil and medicinal plants of Perm Krai (Russian Federation)