Multiple comparisons of organic,microbial, and fine particulate pollutants in typical indoor environments: Diurnal and seasonal variations

This study was performed to investigate the possible sources as well as seasonal and diurnal variations of indoor air pollutants in widely used four different environments (house, office, kindergarten, and primary school) in which people spend most of their time. Bioaerosol levels and species, volatile organic compound (VOC) levels, and PM_2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm) levels were determined in different parts of these environments in parallel with outdoor sampling. Air pollution samplings were carried out in each microenvironment during five subsequent days in both winter and summer in Ankara, Turkey. The results indicated that bioaerosol, VOC, and PM_2.5 levels were higher in the winter than in the summer. Moreover, PM_2.5 and bioaerosol levels showed remarkable daily and diurnal variations, whereas a good correlation was found between the VOC levels measured in the morning and in the afternoon. Bacteria levels were, in general, higher than fungi levels. Among the VOCs, toluene was the most predominant, whereas elevated n-hexane levels were also observed in the kindergarten and the primary school, probably due to the frequent wet cleaning during school days. According to factor analysis, several factors were found to be significantly influencing the indoor air quality (IAQ), and amongst them, VOC-based products used indoors ranked first. The overall results indicate that grab sampling in naturally ventilated places may overestimate or underestimate the IAQ due to the inhomogeneous composition of indoor air caused by irregular exchanges with the outdoor air according to the season and/or occupants' habits.

Implications Seasonal and diurnal variations of VOCs, PM_2.5, bioaerosols in house, office, and schools were observed, in which PM_2.5 and bioaeorosols showed marked both intra- and interday variability, but VOCs did not. VOC-containing products were the most common source of air pollutants affecting the indoor air quality. External factors affecting the indoor air quality were season and indirectly ventilation. A grab sample cannot be representative in evaluating the air quality of a naturally ventilated environment precisely.     

The role of rural communities in the transition to a low-carbon Scotland: a review

The Scottish Government is committed to carbon reduction targets which are the most ambitious across the devolved administrations of the UK. Whilst Scotland operates within broader international and UK policy contexts, it has developed particular programmes and approaches to engage communities in the transition towards low-carbon futures. Rural areas have a role in the transition to a low-carbon Scotland; however, beyond land use and agriculture contributions, little research has explored the “rural” dimension of “low-carbon” transitions. The paper presents a policy and literature review relating to the low-carbon agenda in Scotland. It reflects on Scottish low-carbon policy and governance, the positioning of “rural communities” within this, and the opportunities and challenges this might present. Based on this, we develop an understanding of how rural communities may contribute to a low-carbon Scotland and identify a future research agenda to explore in more detail the nature and relative effectiveness of diverse governance structures to support this.     

Bioleaching of heavy metals from sewage sludge,direct action of Acidithiobacillus ferrooxidans or only the impact of pH?

Journal of Material Cycles and Waste Management - The bioleaching process comprises two mechanisms: direct action of the bacteria and indirect effect of low pH. In this work, the effect of bacteria...     

Screening for plants and rhizospheral fungi with bioremediation potency of petroleum-polluted soils in a Tehran oil refinery area

The contamination of soils by toxic and/or hazardous organic pollutants, especially with crude oil, is a widespread problem. This study was conducted in a petroleum-contaminated area in a Tehran oil refinery to find petroleum-resistant plants and their rhizospheral fungal strains with bioremediation potency. The plants growing in the oil-polluted area were collected and determined taxonomically. Root samples of the plant species were collected from a polluted area and fungal strains determined by laboratory methods and taxonomical keys. The growth ability of the isolated fungal strains was studied in media containing 1%–15% crude oil. Results showed that seven plant species were of the highest density in the contaminated area: Alhagi persarum, Hordeum marinum, Peganum harmala, Phragmites australis, Prosopis farcta, Salsola kali, and Senecio glaucus. The root-associated fungi were isolated and showed that the fungal variation in the oil-polluted area is higher than that in a non-polluted area. The growth assay of isolated fungal strains showed that all studied fungal strains were able to form colonies at the applied concentrations but Alternaria sp. and Rhizopus sp. were the most resistant ones. Some plants were resistant to oil pollution, which also had positive effects on the fungal strains.     

Coupling a Detailed Transport Model to the Integrated Assessment Model REMIND

Environmental Modeling & Assessment - The transport sector is a crucial bottleneck in the decarbonization challenge. To study the sector’s decarbonization potential in the wider systems...     

Using Design-Expert to Optimize the Properties of a Polyethersulfone Ultrafiltration Membrane Through the Incorporation of NH2-MIL-53(Fe) and PVP for Maximum Cr(VI) Removal and Flux

Journal of Polymers and the Environment - In this study, an NH2-MIL-53(Fe) functionalized membrane was fabricated for Cr(VI) removal from contaminated groundwater. Design-Expert was employed to...     

TiO2-NPs and cadmium co-exposure: in vitro assessment of genetic and genomic DNA damage on Dicentrarchus labrax embryonic cells

Environmental Science and Pollution Research - The increased titanium dioxide nanoparticles (TiO2-NPs) spread and their interaction with organic and inorganic pollutants arouses concern for the...     

Sorption of phenanthrene by dissolved organic matter and its complex with aluminum oxide nanoparticles

Intent of this study was to explore the potential application of polymerin, the polymeric, dissolved organic matter fraction from olive oil wastewaters, in technologies aimed at remediating hydrophobic organic compounds (HOCs) point-source pollution. Phenanthrene binding with polymerin was investigated. Moreover, the effect of addition of micro and nanoscale aluminum oxides (Al₂O₃) was studied, as well as sorption of polymerin on the oxides. Phenanthrene binding capacity by polymerin was notably higher than the sorption capacities for both types of Al₂O₃ particles. Polymerin sorption on nanoparticles was nearly 100 times higher than microparticles. In a three-phase system, using microparticles, higher phenanthrene sorption was found by adding into water polymerin, oxides and phenanthrene simultaneously. In contrast, using nanoparticles, a considerable enhancement of phenanthrene sorption was shown by adding phenanthrene to a pre-formed and dried polymerin-oxide complex. These findings support the application of polymerin, especially associated with Al₂O₃ nanoparticles, in remediation of water contaminated with HOCs. This work highlights the significant role of nanoparticles.     

A risk-based decision making approach to determine fireproofing requirements against jet fires

API Publication 2218 is one of the most referred practices for fireproofing of onshore structural supports. Despite the extensive citation, it solely considers the effects of pool fire and rarely addresses jet fire outcomes. This absence of an explicit approach is common among all the other major references. Therefore, the basic objective of this paper is to introduce a new approach for determination of the necessity for fireproofing of structural supports against jet fires. For this purpose, the flame geometry and duration of jet fires are simulated for different leak sizes in identified fire potential sources. Then, following a worst-case analysis, those structures that may be impinged by long enough flames are screened out and then characterized by maximum impingement duration for fireproofing purpose. Moreover, each structure is assigned by a failure rate to estimate the degree of vulnerability through a detailed risk assessment. In this regard a new explanatory term called Structure Failure Rate (SFR) is introduced. This approach also enables researchers to quantify the effect of other protective systems (fire and gas detection, emergency shut-down, depressurization and firewalls) on the level of required fireproofing.