Mercury and selenium were assessed in Mustelus henlei, which is a carnivorous predatory shark that is important for the coastal communities of the northern Mexican Pacific (NMP). Sixty-two individuals were sampled; muscle and liver were isolated and analyzed by atomic absorption spectrophotometry. The mean Hg concentrations (wet weight) obtained for muscle (0.08 ± 0.10 μg g⁻¹) and liver (0.09 ± 0.26 μg g⁻¹) were below the allowed limits (< 1.0 μg g⁻¹ Hg). The average Se concentration was 0.03 ± 0.01 μg g⁻¹ in muscle and 0.13 ± 0.05 μg g⁻¹ in liver. The Se/Hg molar ratio of muscle was 1.83; however, the selenium health benefit value (HBVSₑ) was of 0.08. We calculated that an adult man (70 kg), an adult woman (60 kg), and a child (16 kg) could consume 1595, 838, and 223 g/week of M. henlei muscle, respectively, without risks to health. In conclusion, the concentrations and molar ratio of Hg and Se in M. henlei muscle mean that consumption of this shark’s meat does not represent neither a benefit nor a public health risk.

In this study, the experimental and kinetic modeling investigations were performed to evaluate the ability of mesoporous and microporous canola stalk-derived activated carbon (CSAC) on 2,4-dichlorophenoxyacetic acid (2,4-D) removal from synthetic and natural water in both batch and continuous systems. Three empirical models (pseudo-first-order equation (PFOE), pseudo-second-order equation (PSOE), and the Elovich equation (EE)) and three theoretical models (film diffusion model (FDM), particle diffusion model (PDM), and second-order chemical reaction rate model (SOCRRM)) were compared in terms of diffusion coefficients, maximum 2,4-D adsorption, and rate constants at various operating conditions. CSAC was prepared at 600 °C and activated with water steam under a controlled flow and subsequently characterized by various analytical methods. The results showed that the maximum 2,4-D uptake by CSAC was achieved as 135.8 mg g⁻¹ under a pH of 2 and an initial 2,4-D concentration of 150 mg L⁻¹. The CSAC removed 38.3% of Na⁺, 43.49% of K⁺, 8.96% of Mg²⁺, 45.14% of Ca²⁺, 17.2% of Cl⁻¹, 39.48% of HCO₃⁻, 63.74% of SO₄²⁻, and 100% of the herbicide from agricultural subsurface drainage water and also retained its usability after regenerated by acetone for five cycles. It was concluded that the 2,4-D was adsorbed on the surface of the CSAC through its aromatic ring interaction with the reactive functional groups of the adsorbent. The model result indicated that the PDM is the best-fitting kinetic model for the adsorption of 2,4-D by CSAC, followed by FDM, SOCRRM, PSOE, PFOE, and EE. The mass balance equation based on PDM describes the dynamic behavior of the column satisfactorily. Graphical abstract

Scholarly debates on the unique features of transit-oriented developments (TODs) have surged over the last decade. Studies have examined their amenities and disamenities; however, lacking is exploring the relationship between TOD sound levels and buildings. Understanding this relationship has implications for communities and the urban form from environmental pollution aspects. This study explores the implications of sound on TOD buildings in the Dallas-Fort Worth metropolitan area by comparing them with non-TODs, specifically the relationship between buildings and street characteristics, and sound, as well as the potential effects of this relationship on TOD residents. Data include sound pressure levels through TOD buildings and streets compared with non-TOD buildings and streets. Using a two-level hierarchical linear model (HLM) help examine such characteristics at both micro and macro levels. The findings show that buildings located within TODs are exposed to higher sound levels with 1.4 dB(A) difference. The study provides insights into the relationship between sound, environmental pollution, building science, and transportation-featured elements of the built environment.

Obtaining the pollutant release mass at a timely manner is crucial in emergency response for river pollution accidents. However, compared to the instantaneous source, release mass estimation of finite-duration source has been rarely studied. In addition, few studies involve the influence of partial observation data and observation data with different levels of noise on inversion results. Based on the adjoint equation method (AEM), this study developed a new release mass estimation model to make up the above deficiencies. In this model, one-dimensional physical transport advection–dispersion equation was used as governing equation to describe pollutant transport and the finite-duration sources and instantaneous sources were both considered. Two synthetic experiments and two field experiments were used to evaluate this model. In synthetic experiments, detailed analysis of the influence of observation errors and incomplete concentration data due to equipment failure was conducted. Results indicate that the effect of observation errors on the inverse estimation results was within the relative error of 12%; the incomplete concentration data could also be used to obtain inverse estimation results. The two field experiments gave confidence to the application of this model in release mass estimation in actual pollution accidents with a relative error within 10%. These findings will assist in the decision-making for dealing with actual river pollution accidents.

The ranking of power generation sources is a very important prerequisite for power generation installation planning and power supply security. This study proposed a new multi-criteria system for ranking regional power generation sources in one country, including resources, economy, technology, environment, and society, using 11 sub-criteria. Based on the system, a novel decision-maker (DMs) preference-based integrated MCDM framework involving four methods (Visekriterijumsko Kompromisno Rangiranje (VIKOR), Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE), and Weighted Sum Method (WSM)) was developed for ranking six power generation sources (thermal, nuclear, wind, hydro, solar PV, and biomass) at the level of China’s 30 provinces. Six different preferences of DMs are considered in the ranking according to five criteria. The results show that wind should be the power generation source given the top priority in most provinces in China whereas nuclear power and thermal power are the last choice for 26 provinces. Biomass is the most preferable power source for 17 provinces based on technological preference in which DMs regard the technology criteria is prior to all other criteria. Thermal power would still the preferred or secondary power source for provinces rich in coal resources such as Shanxi, Inner Mongolia, Henan, and Shaanxi.

Cave dwelling is an ancient and unique type of residence in the Loess Plateau of Northern China, where the economics are less-developed. The majority of the local dwellers rely on traditional solid fuels for cooking and heating, which can emit large amounts of particles into both indoor and outdoor environments. In this study, we measured the real-time household concentrations of PM₂.₅ and explored the association between personal daily PM₂.₅ exposure and blood pressure (BP). Cooking and heating activities with different energies made a great variation in the household PM₂.₅ air pollution, and residents using biomass had the highest personal PM₂.₅ exposure. Temperature and relative humidity are both significantly linear correlated with household PM₂.₅ air pollution. Besides, systolic blood pressure (SBP) was demonstrated to be positively associated with personal PM₂.₅ exposure: with each 10-μg/m³ incremental PM₂.₅ concentration when controlling all the other factors, SBP will increase by 0.36 mmHg (95% confident interval (CI) 0.05–0.0.77 mmHg). If solid fuels could be replaced with clean energies, personal PM₂.₅ exposure and SBP would reduce by more than 21% and 3.7%, respectively, calling for efficient intervention programs to mitigate household air pollution of cave dwellings and protect health of those residents.

The internal critical concentration represented by the critical body residue (CBR) is an ideal indicator for reflecting the toxicity of a chemical. Although some authors have realized that the CBR₅₀ can be calculated from the LC₅₀ via the bioconcentration factor (BCF), the effects of exposure time and exposure concentration on the relationship between the LC₅₀ and CBR₅₀ have not been investigated to date. In this paper, the LC₅₀ and CBR₅₀ of ortho-dinitrobenzene in zebrafish were experimentally determined and their relationship was investigated. The results showed that ortho-dinitrobenzene exhibited excess toxicity and cannot completely be identified as a reactive compound based on toxic ratio. Comparison of the measured CBR₅₀ and the CBR₅₀ calculated from the LC₅₀ via the BCF showed that there was a 0.46 log unit difference. Investigation of the relationship between the concentration in fish calculated by the toxicokinetic model and exposure time showed that the bio-uptake of fish was fast and reached a steady state in the toxicity test, indicating that the difference in CBR₅₀ values could not be attributed to the different exposure times used in toxicity and BCF assays. On the other hand, investigation of the measured bioconcentration ratio (BCR) showed that the BCR (or BCFₐₚₚ) decreased with increasing exposure concentration. Compared with the CBR₅₀ calculated from the LC₅₀ via the BCF, the CBR₅₀ calculated from the LC₅₀ via the BCFₐₚₚ is close to the measured CBR₅₀, suggesting that the difference in CBR₅₀ values is attributed to the different exposure concentrations used in the BCF and toxicity assays.

Heavy metals like Cd and Hg removal using novel graphene oxide/ferrous sulfate (GO/FeSO₄) was taken for experimental studies and analysis. In this work, GO/ FeSO₄ was synthesized by both modified Hummer’s and chemical precipitation method. The synthesized composite was characterized by field emission scanning electron microscope (FESEM), Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy for their properties. Brunauer Emmett-Teller (BET) analysis was characterized for the surface analysis of the prepared nanocomposites. FESEM images exhibit flake-like structures in surface morphological studies. FTIR peaks confirmed the presence of carboxyl groups in GO. Raman spectroscopy intensity peak [ID/IG ratio1.18] confirmed the synthesized sample was GO. The experimental parameters such as initial concentration, pH, and adsorbent dosage were optimized to achieve maximum heavy metal removal efficiency. The influence of initial heavy metal concentration (0.2–1 mg/L), pH of solution (pH 3–7), and adsorbent dosage (1–5 g/L) was studied and reported. Adsorption kinetic studies were performed and the process was found to fit well with pseudo-second-order kinetics.

Phenanthrene (PHE), a tricyclic polycyclic aromatic hydrocarbon (PAH), is ubiquitously found in aquatic environments. It is one of the major components in PAH mixtures. It has been identified as one of the 16 priority PAHs for toxicological evaluations. PHE is reported to induce lethal and sub-lethal toxicity in various aquatic indicator organisms. However, no toxicological data of PHE in anuran amphibians could be found. Amphibian larvae (tadpoles) develop in aquatic habitats. Therefore, exposure to PHE could negatively impact their development and fitness in later periods as they move in to the terrestrial habitat following metamorphosis. In the present study, we have analyzed the effects of PHE in Euphlyctis cyanophlyctis tadpoles. PHE induced concentration-dependent lethal effects in the tadpoles. The estimated LC₅₀ values were 16.52, 15.29, 13.69, and 12.28 mg/L at 24, 48, 72, and 96 h of exposure respectively. These LC₅₀ values are significantly higher than the reported environmental concentration of PHE. However, the strong negative correlation (R² = 0.997, p < 0.001) between the LC₅₀ value and exposure time indicates that longer exposure to lower concentration may cause significant lethal effects. Besides, PHE at environmentally relevant concentrations induced significant sub-lethal toxicities. Exposure to sub-lethal concentrations was found to be genotoxic in erythrocyte micronucleus as well as comet assays. Sub-lethal concentrations of PHE significantly increased superoxide dismutase activity and tissue glutathione level as well as induced lipid peroxidation. The present findings clearly indicate that PHE is a potential threat to the early life stages of amphibians. Further investigations are necessary to ascertain the implications of these early effects during adult life stages.

Carbon emissions in the transportation sector are of great concern, since they are the third leading contributor to China’s carbon emissions. This research examines the decoupling relationship between economic outputs and carbon emissions of 11 provinces in 2000–2016 by focusing on Yangtze River Economic Belt (YREB), which is the densest traffic and economic corridor in China. Although many studies have focused on the decoupling state and its driving forces between economic outputs and carbon emissions, few studies further addressed the microscale analysis for decoupling drivers. This paper reveals the characteristic, inequality contribution ratio, and dynamic evolution of the drivers by integrating Dagum’s Gini ratio with kernel density estimation in YREB. Results are as follows: (1) The decoupling states presented weak decoupling state at the whole belt in the majority of the latter observed sub-periods. The decoupling states at the provincial level turned more satisfactory during the four observed sub-periods, especially for Shanghai and Zhejiang. (2) The energy intensity (EI) effect is the predominant driver for promoting the decoupling state in the vast majority of provinces, whereas value added per capita effect is the major role for inhibiting the decoupling state. (3) During the four observed sub-periods, the Gini inequality and transvariation intensity of the EI effect between sub-regions are the main sources of the provincial differences in YREB. The driving force of EI effect is increasing, but the provincial differences are expanding in the upstream and downstream regions by analyzing its dynamic evolution. Understanding the temporal and spatial microscale inequality of the decoupling drivers provides governments with differentiated and forward-looking suggestions towards coordinating regional economic growth and carbon emissions reduction.