The particle penetration factor is an important parameter to determine the concentration of indoor particles. In this paper, a mathematical model for calculating this parameter was established by combining with the decay of the indoor PM₂.₅ and CO₂ concentrations measured in a bedroom with an air cleaner. The convergence of the penetration factors was analyzed under different working conditions. The results show that the particle penetration factors converge to stable values within the range of 0.69 to 0.84 close to the value from the empirical formula when the indoor PM₂.₅ concentration decays to stable values. When the role of particle deposition is ignored, the penetration factors at the low and middle airflow modes are 0.78 and 0.69, respectively. The particle penetration factors are mainly determined by the clean air delivery rate (CADR) of the air cleaner, clearance airflow, and I/O ratio during the balanced phase when the roles of indoor particle deposition and exfiltration can be ignored. This work can provide a convenient method for the calculation of the particle penetration factor.

Due to their pervasive applications, phthalic acid esters or phthalates have ample presence in all environmental compartments. A principal source of their existence in freshwater is phthalate-laden wastewater treatment plant effluents. For its sustainable operation and biogas production, wastewater treatment scheme of up flow anaerobic sludge blanket (UASB) and polishing pond is more prevalent in developing countries. This yearlong study focused on evaluating the occurrence, fate and risk of four priority phthalates, diethyl phthalate (DEP), dibutyl phthalate (DBP), benzylbutyl phthalate (BBP), and diethylhexyl phthalate (DEHP) in a UASB+ polishing pond-based wastewater treatment plant. Concentration of the phthalates in raw wastewater ranged from nd to 17.36 μg/L (DEP), 0.92 to 18.26 μg/L (DBP), nd to 6.54 μg/L (BBP), and nd to 53.21 μg/L (DEHP). DEHP concentrations in UASB sludge were below 100 mg/kg, the recommended limit by the European Union for safe disposal of dewatered sludge. All four compounds were removed approximately 80% in the wastewater treatment plant, with larger removal in polishing pond than UASB. Sorption contributes a significant portion of BBP and DEHP removal (15–24%) in UASB than DEP and DBP (0–3%). Seasonally, larger removals of phthalates were observed during the summer season. Risk assessment showed that the treated effluents had low risk of DEP, DBP, and BBP. However, the hazard quotient (HQ) of DEHP was greater than 1. To comply with regulations, dilution requirement of effluents was investigated which showed that a dilution factor of 4.4 in summer and 2.1 in winter is required for effluents of UASB + Pond-based treatment plant.

Thermal desorption (TD) technology is the preferred treatment technology for treating soil contaminated by organic compounds. Under laboratory conditions, eggshell and plant ash were studied as additives during thermal desorption to further improve the soil thermal desorption efficiency and the quality of soil after thermal desorption. The results showed that temperature was still an important factor affecting the soil quality and removal efficiency of PAHs (polycyclic aromatic hydrocarbons). The efficiency of the thermal desorption of soil was significantly improved (from 91.7 to 96.6%) by adding two additives, and the agglomeration of the soil was alleviated to some extent according to the decreased amount of large soil particle (100–400 μm). Moreover, the TOC (total organic carbon) and CEC (cation exchange capacity) of the soil were increased. This work suggested that the addition of similar alkaline additives to the soil during thermal desorption might have a positive impact on both thermal desorption behavior and soil quality.

This paper investigates the relationship between greenhouse gas emissions, energy consumption, and output growth among African OPEC countries (Libya, Nigeria, Angola, Algeria, Equatorial Guinea, and Gabon) using the panel autoregressive distributed lag model (PARDL) estimated by means of mean group (MG) and pooled mean group (PMG) for the period 1970–2016. The paper estimated three panel models comprising the components of greenhouse gasses which includes nitrous oxide, carbon dioxide (CO2), and methane and examined their relationship with economic growth and energy consumption. The findings of the study showed evidence of a positive impact of economic growth on both CO2 and methane emissions in the long run. Its impact on nitrous oxide emissions although positive was found to be statistically insignificant. Energy consumption was also found to produce an insignificant positive impact on CO2, methane, and nitrous oxide emissions in the long run. In the short run, economic growth exerts a significant positive effect on methane emissions; however, its effect on CO2 and nitrous oxide emissions although positive was found to be statistically insignificant. Energy consumption produces an insignificant impact on all components of greenhouse gasses in the short run. In addition, our empirical results showed the presence of a non-linear relationship between methane emissions and economic growth, confirming the existence of the environmental Kuznets curve (EKC) only in the case of methane emissions model.

De-carbonization of the transport sector is an important pathway to climate-change mitigation and presents the potential for future lower emissions. To assess the potential quantitatively under different optimization measures, this paper presents a hybrid model combining an integrated machine learning model with the scenario analysis. We compare the training accuracy of the back-propagation neural networks (BPNN), Gaussian process regression (GPR), and support vector machine (SVM) fitting model with different training datasets. The results indicate that the performance of the SVM model is superior to other methods. And the particle swarm optimization (PSO) algorithm is then used to optimize hyper-parameters of the SVM model. Two scenarios including business as usual (BAU) and best case (BC) are set according to the current trends and target trends of driving factors identified by the extended stochastic impacts by regression on population, affluence, and technology (STIRPAT) model. Finally, to find the de-carbonization potentials in the transport sector, the PSO-SVM model is applied to predict transport emissions from 2015 to 2030 under two scenarios. Results show that transport emissions reduce by about 131.36 million tons during 2015–2020 and 372.86 million tons during 2021–2025 in the BC scenario. The findings can effectively track, test, and predict the achievement of policy goals and provide practical guidance for de-carbonization development.

Due to expected changes in climate, it is predicted that disease-carrying mosquitoes will expand their geographical range, resulting in increased use of insect growth regulators (IGRs) to face their proliferation. Among IGRs, pyriproxyfen (PXF) is widely used and has been shown to prevent larvae from developing into adults, rendering them unable to reproduce. However, because of the similarity of crustacean and insect endocrine systems, PXF could also impact aquatic crustaceans. In addition, when spreading in the environment, PXF is found in a mixture with other pollutants such as metallic trace elements, which could alter its effect. Consequently, the present work was devoted to analysing the effects of PXF on the methylfarnesoate (MF) hormonal pathway of the freshwater amphipod Gammarus pulex, as well as its combined binary effects with cadmium (Cd), by measuring MF concentration, as well as the relative transcriptional expression of the farnesoic acid O-methyltransferase (FAMeT) (enzyme limiting the MF production), the methoprene-tolerant receptor (Met), and the broad-complex (BrC) as a transcription factor. Results revealed that single exposures to PXF or Cd have mainly overexpressed FAMeT, Met, and BrC but did not significantly affect MF concentration. Conversely, the mixture exposures seemed to suppress these effects and even achieve antagonistic effects. This work confirmed that PXF single exposure could impact non-target organisms such as amphipods through changes in hormonal pathways of MF. In the same way, it highlighted that Cd could also impair the endocrine system of exposed organisms. However, antagonistic effects have been observed in exposure to mixtures, suggesting different long-term consequences on the growth of amphipods under realistic exposure conditions.

The genotoxicity and cytotoxicity of lanthanum (La(III)) were studied in fish micronucleus analysis in erythrocytes of the rare minnow (Gobiocypris rarus). Fish were exposed to 0.04, 08, 0.16, 0.32, and 0.80 mg L–¹ of La concentration for 21 days. Several important morphological alterations of the nucleus were noted, such as the ratio of micronucleated erythrocyte, and total ratio of erythrocytes with nuclear anomalies, blebs, notches, and so on. The total ratio of nuclear anomalies was significantly higher (P < 0.05) in G. rarus exposed to La(III) (except for 0.04 mg L–¹) compared with the control. Hypsometric analysis indicated significant dose-dependent changes in erythrocyte and nucleus dimensions (P < 0.05). Various abnormal morphological forms of erythrocytes were also observed. These results showed that La(III) was cytotoxic to erythrocytes of the rare minnow.

Plants can improve indoor air quality, and affect the work efficiency and subjective perceptions. However, the conclusions of existing experiments regarding how plants affect work efficiency are not uniform. To further explore this subject, this study designed five different working conditions, and selected a variety of “general tasks” and “tasks requiring concentration” as operational tasks. The effects of the plant arrangement and quantity on work efficiency were studied by analyzing the performance of subjects in different working conditions. The effects of the plants on the subjective perceptions were investigated using questionnaires. The experimental results show that the effects of plants on work efficiency were related to the nature of the work, the placement of the plants, and the number of plants. Plants had no effect on the efficiency of general tasks such as “symmetry breadth,” but had a positive impact on the efficiency of general tasks such as “operational breadth.” Moreover, by changing the arrangement and quantity of plants, the efficiency of general tasks could be increased by up to 19.1%. In contrast, plants placed within a coincident view had a negative impact on the efficiency of “tasks requiring concentration,” and the work efficiency could be reduced by up to 12.4%. In addition, plants could increase enthusiasm and willingness to work by 12.5% and 11.8%, respectively.

Organic enrichment due to human impact is one of the major threats that affect benthic communities in semi-enclosed marine ecosystems, such as the Mediterranean Sea. However, many emerging sources of organic pollutants, such as those released to nature through human practices related to esthetics and cosmetics, remain underestimated, despite being an increasingly important source of organic matter input following a decade of expansion by the cosmetic industry. Therefore, an experiment was designed to explore the influence of collagen, the main component of commercialized skin anti-aging products, on a Mediterranean community of free-living marine nematodes from a beach in Rimel, northeast Tunisia. The effects of exposure for 30 days to a control treatment and three test treatments, corresponding to three levels of sedimentary enrichment with collagen (3, 6, and 12 ppm dry weight (DW)), were examined using a microcosm approach. Reductions in abundance and diversity were noted with an increase in collagen enrichment, together with a slight increase in individual weight. The presence of three species characteristic of control microcosms, Ptycholaimellus ponticus, Theristus modicus, and Kraspedonema reflectans, was clearly affected at the lowest dose; these were therefore classified as “collagen-sensitive.” In contrast, the numbers of “collagen-tolerant” species, including Sigmophoranema rufum, Lauratonema hospitum, Enoploides spiculohamatus, and Trichotheristus mirabilis, increased significantly in the treated microcosms.

The Aedes albopictus mosquito is a vector of several deadly diseases of humans and domesticated animals. Usually, synthetic insecticides are used for mosquito control. The excessive use of synthetic insecticides is hazardous for humans and the environment. Therefore, there is a need to develop environment-friendly and novel mosquito larvicides. In the current study, we evaluated larvicidal and bite protection properties of Seriphidium brevifolium essential oil (SBEO) and its active constituents against this mosquito. SBEO and its active constituents, α, β-thujone, and limonene, were toxic to A. albopictus, with LC₅₀ values of 21.43, 45.99, 47.38, and 49.46 μg/mL. The cream formulation of EO at 5 % (w/v) provided complete protection against mosquito bites until 70 min after application. Among the EO constituents tested, α and β-thujone showed considerable protections against mosquito bites but lower as compared with the whole oil. Furthermore, 1:1 combinations of active constituent α-thujone and β-thujone and 1:1:1 combinations of α-thujone, β-thujone, and limonene displayed a synergistic effect against the larvae. Particularly, the EO and its active constituents were safer to Poecilia reticulata a mosquito predator, with LC₅₀ ranging from 3934.33 to 14,432.11 μg/mL. Our current study indicated that SBEO and some of its constituents can be used for the control of A. albopictus mosquito, as a novel alternative to hazardous synthetic insecticides and to overcome the problem of increasing insecticides resistance.