This meta-analysis aimed to comprehensively assess the effects of long-term air pollution exposure on the risk of type 2 diabetes mellitus (T2DM). Studies were selected from three electronic databases. Random- or fixed-effect model was used to obtain the pooled hazard ratios (HRs) and corresponding 95% confidential intervals (CIs). Stratified analyses by regions of the studies and length of follow-up were conducted to assess the effects in different subgroups. Sensitivity analyses by omitted studies one by one, as well as adjusting certain confounding factors, were also conducted. The search resulted in 1878 studies, among which 16 studies with 18 cohorts were included. The incidence of T2DM was significantly associated with 10 μg/m³ increase of PM₂.₅ (overall HR = 1.11, 95% CI: 1.03, 1.19) and PM₁₀ (overall HR = 1.12, 95% CI: 1.01, 1.23) exposure. Stratified analyses confirmed that PM₂.₅ was significantly associated with increased T2DM incidence in American countries but not European countries. The results in the long follow-up subgroup also confirmed that exposure of PM₂.₅ and PM₁₀ was associated with increased T2DM incidence. Interestingly, educational level and gender could potentially affect the impacts of PM₁₀ and PM₂.₅ on T2DM incidence. The findings show long-term exposure to PM₂.₅, and PM₁₀ could significantly increase the incidence of T2DM, especially in cohorts with long follow-up time.

The particulate matter emissions related to the braking of railway rolling stock are investigated using a reduced scale braking device. Samples of organic materials and cast iron discs are tested for different nominal contact pressures and disc surface temperatures, representative of real conditions. The aim of this work is to investigate the influence of braking conditions on the global amount of particles emitted, their distribution in number and size, and their morphological and chemical characteristics. To be representative, the tested conditions are designed to dissipate the same amount of energy for all the braking events by adjusting the pad application duration. The results show that for the same dissipated energy, a temperature increase above a transition value in the range of 230–280 ∘C depending on the braking conditions modifies the size and number distributions of the generated particles. The results obtained are of interest to better represent their propagation through CFD modelling according to the characteristic of the particle emission.

Mercury (Hg) is deposited temporarily in soil and can be remobilised into rivers and seas. Given that rivers are a significant part of the mercury budget in the southern Baltic region (inland sea located in northern Europe) and meteorological changes (e.g. intense rain, drought) are observed more frequently, it is important to recognize the factors affecting the cycling of bioavailable Hg forms. The aim of this study was to identify the processes influencing the changes of labile and stabile mercury proportion in soil and the potential impact on the outflow of labile Hg into fluvial systems. For this purpose, soil samples, river sediments, and river water were collected from the Reda River (southern Baltic Sea catchment area) during the 2015 hydrologic year. The material was analysed for total and particulate mercury content and Hg forms, by a thermo-desorption method. The analysis showed that due to changes of meteorological and hydrological conditions Hg can enter rivers and then be introduced into the marine environment in various forms. On the one hand due to high precipitation events washing out of labile (i.e. bond with halogenides, MeHg, HgSO₄), Hg forms into the river can be enhanced which affects increasing of availability of the most dangerous Hg form in the water systems. On the other hand the same event can cause the limitation of bioavailable mercury forms by a conversion of labile Hg into the most stable one (HgSO₄ ➔ HgS) under anaerobic conditions.

Oil extraction is one of the causes of soil contamination with the total petroleum hydrocarbons. The objective of this study was to clarify the effect of Asteraceae plants on the degradation of petroleum hydrocarbon in contaminated soil. Initial soils with 40 and 90 g kg⁻¹ of total petroleum hydrocarbon (TPH) were prepared. There were three treatments: (1) no addition, (2) addition of FeCl₃ and nitrilotriacetic acid (NTA) solution, and (3) addition of FeCl₃ + NTA and the cultivation of nine Asteraceae plants. The concentration of TPH was measured using infrared spectrophotometer, 2 and 3 months after transplanting (MAT). Shoot and root dry weights were measured 3 MAT. The concentration of TPH in soil cultivated with Cosmos caudatus was lower than that of the initial soil (40 g kg⁻¹ TPH), 2 MAT. The concentrations of TPH in soils cultivated with Calendula officinalis, Callistephus chinensis, C. caudatus, and Tagetes sp. were also lower than that in the initial soil, 3 MAT. The concentrations of TPH in soils cultivated with Achillea filipendulina, Anthemis tinctoria, Tagetes erecta, Chrysanthemum coronarium, C. officinalis, C. chinensis, and C. caudatus were lower than that in the initial soil (90 g kg⁻¹ TPH), 2 MAT. The concentrations of TPH in soils cultivated with T. erecta, A. tinctoria, Zinnia elegans, C. chinensis, C. caudatus, and Tagetes sp. were lower than that in the initial soil, 3 MAT. A. filipendulina and C. coronarium died at both 40 and 90 kg⁻¹ TPH soils. These results suggest that the roots of Asteraceae plants degrade petroleum hydrocarbon in contaminated soil and C. chinensis and Z. elegans are more suitable for using TPH remediation. Plant survival and extensive root system are important factors for the remediation of TPH in contaminated soil.

The CO₂ injection capacity directly affects the CO₂ storage efficiency. Injection temperature and formation sloping degree affect the CO₂ injection capacity. Based on the actual geological conditions of the Shiqianfeng Formation in the Ordos Basin of China, a three-dimensional (3D) simulation model was established to evaluate pressure, temperature, CO₂ spatial distribution, and injection amount. A total of 17 simulation schemes were carried out using the TOUGH2–ECO2N fluid property module. The results showed that the injection temperature had a significant impact on the CO₂ injection capacity in the different sloping degree formations. Increasing the injection temperature resulted in increased formation pressure, CO₂ gas phase, dissolved phase, and total injection amount, while decreasing the CO₂ concentration, and the formation pressure changed obviously with the formation sloping degree. The larger the formation sloping degree was, the less the CO₂ injection amount. Higher injection temperature and smaller sloping degree formation were more favorable for CO₂ injection, and the CO₂ injection capacity was stronger, signaling that it should be selected to store CO₂ in the future.

Anaerobic digested residue (DR) is the main by-product from biogas plants, and it is predominantly used as organic fertilizer after composting. To resolve the problems of long duration and nitrogen loss in conventional composting, bulking agents are always added during the composting process. In this study, oyster shell (OS) was used as a bulking agent for DR composting. Four treatments were conducted by mixing DR and OS at different concentrations (0%, 10%, 20% and 30%, based on wet weight) and then composting the mixtures for 40 days. The results showed that the organic matter (OM) degradation efficiency was enhanced by 5.62%, 12.15% and 16.98% with increasing amounts of OS addition. The increased content of microbial biomass carbon in the compost indicated a suitable living environment for aerobic microbes with added OS, which could explain the increased OM degradation efficiency. Compared with the control, the NH₃ emissions in the treatments with 10%, 20% and 30% OS were decreased by 13.81%, 33.33% and 53.76%, respectively. The increase in total nitrogen content in the compost is probably due to the absorption of NH₃ by OS. Results indicated that OS is a suitable bulking agent for DR composting and that the addition of 20–30% OS can significantly enhance composting performance.

This study investigates the asymmetric dynamic effects of financial development on ecological footprint in Nigeria over the period 1971–2014 using the nonlinear autoregressive distributed lag (NARDL) framework. Ecological footprint in Nigeria is classified into carbon footprint, non-carbon footprint, and total ecological footprint. The results show that in Nigeria, a positive shock in financial development (an increase in financial development) has significant reducing effect on ecological footprint (i.e., improves environmental sustainability) while a negative shock in financial development (a decline in financial development) has significant increasing effect on ecological footprint (i.e., deteriorates environmental sustainability). Asymmetry test shows that a significant difference exists in how negative and positive shocks in financial development impact on carbon footprint and total ecological footprint, but not for non-carbon footprint. On the basis of the total ecological footprint, the adjustment asymmetry from the dynamic multiplier graph shows that the response of ecological footprint to a negative shock in financial development is stronger. Further findings from the analysis show that economic growth, energy consumption, urbanization, and economic globalization are all drivers of environmental sustainability in Nigeria. Overall, the results highlight the need for a deepened financial system, as part of the strategies for achieving sustainable development in Nigeria.

Radon exhaled from building material surfaces is an important source of indoor radon. Yangjiang, located in the southern part of mainland China, is well-known as a high background radiation area (HBRA). Rather, high levels of radon and thoron concentration have been observed in adobe and brick houses. Reducing the indoor radon concentration remains an important issue in the high background radiation areas of China and the world. Generally, the walls of Chinese dwellings are solid. In this paper, a simple one-dimensional model for predicting the radon diffusion in a cavity wall is proposed, and an analysis formula describing the radon exhalation rate from cavity wall surfaces is presented. The influence on the radon exhalation rate due to leakage through structural joints and building material cracks is analyzed. The simulation results indicate that the radon exhalation rate from a cavity wall surface is far lower than that from a solid wall. The structure of cavity walls themselves is therefore useful as a mechanism for reducing the indoor radon in high background radiation areas across the world.

The study presented in this paper evaluated the effectiveness of surfactants in enhancing mass removal of organophosphorus pesticides (OPPs) from soil under highly alkaline conditions and potential for enhancing in situ alkaline hydrolysis for treatment of OPPs, particularly parathion (EP3) and methyl parathion (MP3). In control and surfactant experiments, hydrolysis products EP2 acid, MP2 acid, and PNP were formed in non-stoichiometric amounts indicating instability of these compounds. MP3 and malathion were found to have faster hydrolysis rates than EP3 under the conditions studied. All surfactants evaluated increased solubility of OPPs under alkaline conditions with four nonionic alcohol ethoxylate products providing the greater affect over the polyglucosides, sulfonate, and propionate surfactants evaluated. The alcohol ethoxylates were shown to provide substantial mass removal of OPPs from soil. Hydrolysis rates were typically slower in the presence of surfactant, despite the relatively higher aqueous concentrations of OPPs; this was likely due to micellar solubilization of the OPPs which were therefore less accessible for hydrolysis. The results of this study support the use of surfactants for contaminant mass removal from soil, particularly under alkaline conditions, and may have implications for use of some surfactants in combination with other technologies for treatment of OPPs.

Street dust and soil samples were collected from three study areas in Jinhua, China: a commercial area and two urban districts. The concentrations of nickel (Ni), lead (Pb), copper (Cu), cadmium (Cd), and particularly zinc (Zn) in street dust exceeded soil background values and Chinese soil screening safe levels in some areas. Zn and Cd concentrations in street dust appeared to pose health concerns in the majority of sample sites, but their levels in soils were noticeably lower, indicating possible contamination from atmospheric deposition. Of the three areas, the most severe pollution occurred in Jindong (JD) District. Practically all the samples from JD District showed contamination to some degree. Based on pollution indices, the contamination levels of heavy metals among the studied sites were ranked in the following descending order: JD District > commercial area (CA) > Wucheng District. Source metal identification assessment revealed that the majority of metals in street dust from Jinhua were significantly related to industrial and traffic activities. Health risk assessment was performed based on the US-Environmental Protection Agency model, and the results showed that virtually, no health risk existed from exposure to individual metals in dust particles. However, the noncarcinogenic risk exponentially increased through exposure to various metals in dust. Thus, the majority of hazard index values surpassed the acceptable level. For carcinogens, the carcinogenic risks of each metal did not supersede the acceptable range for children. This observation demonstrates that although the carcinogenic risk is acceptable, the noncarcinogenic risk remains a genuine health concern for local children.