Regarding the importance of the prevention of hazards and adverse environmental impacts in industrial and populated areas such as southern parts of Tehran city, the response of impulsive period ground-supported tanks were assessed. Having considered the study area's soil properties, the response of ground-supported tanks was modelled. Regarding the soil properties of southern parts of Tehran, the soil structure interaction method explained in FEMA 368 revealed that the interactional impulsive period (~T) was greater than non-interactional one (T). In addition, results showed that Poisson's ratio and stiffness ratio (K/Kx) were more effective regarding the response of the interactional period of ground-supported tank systems. According to the achieved results, the liquid mass density effect on impulsive period was as low as the thickness of the ground-supported walls effect. Results showed that wall materials significantly affected the variation within the impulsive period. Generally, concrete materials were shown to be more periodic than steel materials. Overall, in southern parts of Tehran, when the soil fluid structure interaction method was used, the period increased from 1 to up to 3.6 times greater than the normal impulsive period.

Environmental heavy metal exposure has been considered to be the risk factor for neurodevelopmental disorders in children. However, the available data on the associations between multiple metals exposure and the risk of dyslexia in China are limited. The purpose of our study was to examine the associations between urinary metal concentrations and Chinese dyslexia risk. A total of 56 Chinese dyslexics and 60 typically developing children were recruited. The urinary concentration of 13 metals were measured by inductively coupled plasma-mass spectrometer (ICP-MS). Binary logistic regression and the Probit extension of Bayesian kernel machine regression (BKMR-P) were used to explore the associations between multiple metal exposure and the risk of Chinese dyslexia. Our results indicated that Co, Zn and Pb were significantly associated with Chinese dyslexia in the multiple-metal exposure model. After adjusting the covariates, a positive association was observed between Pb and the risk of Chinese dyslexia, with the odds ratio (OR) in the highest quartiles of 6.81 (95%CI: 1.07–43.19; p–trend = 0.024). Co and Zn were negatively associated with the risk of Chinese dyslexia. Compared to the lowest quartile, the ORs of Co and Zn in the highest quartile are 0.13 (95%CI: 0.02–0.72; p–trend = 0.026) and 0.18 (95%CI: 0.04–0.88; p–trend = 0.038), respectively. In addition, BKMR-P analysis indicated that with the cumulative level across Co, Zn and Pb increased, the risk of Chinese dyslexia gradually declined and then rebounded, albeit non-significantly, and Pb was the major contributor in this association. In general, the urinary concentrations of Co, Zn and Pb were significantly associated with Chinese dyslexia. More prospective studies are needed to confirm the health effects of multiple metals exposure in children with Chinese dyslexia.

Single-chemical thresholds cannot comprehensively evaluate the risk of chemical mixture exposure in indoor air. Moreover, a large number of researches have focused on short-term and high-concentration co-exposure scenarios related to different species, based on diverse endpoints, which hampers the application and improvement of existing risk evaluation models of chemical mixture exposures. More importantly, current risk evaluation models are not user-friendly for construction practitioners who do not have sufficient toxicological knowledge. Therefore, in this study, an inhalation experiment system and a hazard index (HI) were developed to investigate the risks associated with low-concentration and long-term inhalation exposure scenarios of formaldehyde and benzene, individually and combined, based on Drosophila melanogaster mortality. The results showed that the system exhibited good reproducibility in providing stable exposure concentrations during D. melanogaster life cycle. Furthermore, in a range of experimental concentrations, the interaction between formaldehyde and benzene was additive or synergistic, which was concentration- and ratio-dependent. This study is of great significance in harmonising and providing toxicity data under long-term and low-concentration exposure scenarios, which is beneficial for establishing a new user-friendly risk evaluation model for indoor chemical mixture exposures. It should be noted that the proposed HI value could indicate the hazard degrees of long-term inhalation exposures of formaldehyde and benzene, individually and combined, to D. melanogaster. However, the applicability of this index requires further experiments to evaluate the exposure risks of other volatile organic compounds (VOCs) to D. melanogaster.

Cadmium (Cd) is a toxic heavy metal that is widely distributed in the environment. However, the mechanisms linking Cd exposure and type 2 diabetes risks are not completely elucidated. In this study, we aim to investigate the roles of C-reactive protein (CRP) on the association between urinary Cd and type 2 diabetes risk. We determined urinary Cd and plasma CRP concentrations among 3,140 adults from Wuhan-Zhuhai cohort. Dose-response relationships between urinary Cd, plasma CRP, and type 2 diabetes were explored using multivariate logistic regression and linear mixed regression models. Mediation analysis was performed to investigate the role of plasma CRP in the associations between urinary Cd and type 2 diabetes risk. With adjustment for potential confounders, the odds ratios (ORs) of type 2 diabetes showed an upward trend when urinary Cd concentration gradually increased (P trend <0.01). Significantly positive dose-response relationships were observed between urinary Cd and plasma CRP, as well as between plasma CRP and type 2 diabetes risk. Compared to those when both Cd and CRP levels were low, the adjusted ORs (95%CI) of type 2 diabetes was the highest [2.053(1.395–3.020)] in individuals with high levels of urinary Cd and plasma CRP. Mediation analysis estimated that plasma CRP mediated 4.01% of the association between urinary Cd and type 2 diabetes risk [mediating effect: OR (95%CI) = 1.019(1.002–1.057)]. Individuals with high levels of urinary Cd and plasma CRP had a much higher risk of type 2 diabetes. Plasma CRP may serve as a mediator in the association between urinary Cd and type 2 diabetes risk, providing clues for further study on the biological pathway for type 2 diabetes related to Cd exposure.

The occurrence and transportation of antibiotics in biofilms from natural and engineered sources have attracted increasing interests. Nevertheless, the effects of extracellular polymeric substances (EPS) on the responses of biofilms to the exposure to antibiotics are not clear. In this study, the effects of EPS on the sorption and biological responses to one representative antibiotic, sulfamethizole (STZ), in model biofilms were investigated. Proteins dominated the interactions between the EPS and the STZ and the EPS from a moving bed biofilm reactor exhibited the strongest interaction with the STZ. The EPS served as important reservoirs for the STZ and the tested biofilms all showed reduced sorption capacities for the STZ after the EPS were extracted. The respiratory rates and typical enzymatic activities were reduced after the EPS were extracted. High-throughput 16S rRNA gene sequencing results confirmed that the bacterial community in the biofilm without the EPS was more vulnerable to antibiotic shock as indicated by the community diversity and richness indices. A greater increase in the abundance of susceptible species was observed in the natural biofilm. The results comprehensively suggested that the EPS played important role in biosorption of STZ and alleviated the direct damage of the antibiotic to the cells; in addition the extent of the bacterial community response was associated with the origins of the biofilms. Our study provided details on the responses of multi-species biofilms to the exposure to an antibiotic and highlighted the role of the EPS in interacting with the antibiotic, thereby providing a deeper understanding of the bioremediation of antibiotics in real-life natural and engineered biofilm systems.

The coexistence of per- and polyfluoroalkyl substances (PFASs) and heavy metals have been found in soils. However, the interaction between the combined pollutants in soils remains unclear. In this study, the adsorption processes of single and combined Cr(VI) and chlorinated polyfluoroalkyl ether potassium sulfonate (F–53 B) in red, yellow and black soils were simulated. When compared with the single F–53 B and Cr(VI), the adsorption amount of the combined F–53 B and Cr(VI) on soils changed with the types of soils. The interactions between F–53 B and Cr(VI) in soils affected their adsorption behavior. The adsorption of the combined F–53 B and Cr(VI) best fit second-order kinetics and the Freundlich equation. Moreover, aluminum and iron oxides are highly correlated with adsorption of F–53 B and Cr(VI). Both F–53 B and Cr(VI) can form complexes with aluminum and iron oxides through electrostatic interactions, but PFOS could be bridged with iron oxides to form an inner sphere complex and with aluminum oxides to form an outer sphere complex. The coexistence of F–53 B and Cr(VI) could change the fluorescent group of dissolved organic matter (DOM) in soils due to the complexation between F–53 B and DOM. In addition, F–53 B increased the acid-soluble portion of Cr and decreased its residual form, which promoted the environmental risk of Cr in soils.

Selenium (Se) plays an indispensable role in minimizing cadmium (Cd) hazards for organisms. However, their potential interactions and co-exposure risk in the naturally Se–Cd enriched paddy field ecosystem are poorly understood. In this study, rice plants with rhizosphere soils sampled from the Enshi seleniferous region, China, were investigated to resolve this confusion. Here, translocation and bioaccumulation of Cd showed some abnormal patterns in the system of soil-rice plants. Roots had the highest bioaccumulation factors of Cd (range: 0.30–57.69; mean: 11.86 ± 14.32), and the biomass of Cd in grains (range: 1.44–127.70 μg, mean: 36.55 ± 36.20 μg) only accounted for ∼10% of the total Cd in whole plants (range: 14.67–1363.20 μg, mean: 381.25 ± 387.57 μg). The elevated soil Cd did not result in the increase of Cd concentrations in rice grains (r² = 0.03, p > 0.05). Most interestingly, the opposite distribution between Se and Cd in rice grains was found (r² = 0.24, p < 0.01), which is contrary to the positive correlation for Se and Cd in soil (r² = 0.46, p < 0.01). It is speculated that higher Se (0.85–11.46 μg/g), higher Se/Cd molar ratios (mean: 5.42 ≫1; range: 1.50–12.87), and higher proportions of reductive Se species (IV, 0) of the Enshi acidic soil may have the stronger capacity of favoring the occurrence of Se binding to Cd ions by forming Cd–Se complexes (Se²⁻ + Cd²⁺ =CdSe) under reduction conditions during flooding, and hence change the Cd translocation from soil to roots. Furthermore, the negative correlation (r² = 0.25, p < 0.05) between the Cd translocation factor (TFwₕₒₗₑ gᵣₐᵢₙₛ/ᵣₒₒₜ) and the roots Se indicates that Cd translocation from the roots to rice grains was suppressed, possibly by the interaction of Se and Cd. This study inevitably poses a challenge for the traditional risk assessment of Cd and Se in the soils-crops-consumers continuum, especially in the seleniferous area.

Applications of aluminium (Al) salt or lanthanum (La) modified bentonite (LMB) have become popular methodologies for immobilizing phosphorus (P) in eutrophic lakes. The presence of humic substances, has been shown to inhibit this form of treatment due to the complexation with La/Al. However, the effects of other dissolved organic matter (DOM), especially that derived from phytoplankton (the dominant source in eutrophic lakes) are unknown. In this study, the interaction with La/Al of Suwannee River Standard Humic Acid Standard II (SRHA) and algae-derived DOM (ADOM) were investigated and compared. Differed to SRHA which was dominated by polyphenol-like component (76.8%, C1-SRHA), majority in ADOM were protein-like substance, including 41.9% tryptophan-like component (C2-ADOM) and 21.0% tyrosine-like component (C3-ADOM). Two reactions of complexation and coprecipitation were observed between SRHA/ADOM and La/Al. Complexation dominated at low metal inputs less than 10 μM and coprecipitation was the main reaction at higher metal inputs. For ADOM, the tryptophan-like component (C2-ADOM) was the important component to react with metal. The reaction rate for C2-ADOM with La were about two-third of that for C1-SRHA, indicating that the influence of C2-ADOM was significant during the P immobilization by La/Al-based treatment in eutrophic lakes. The P removal data in the presence of ADOM confirmed the significant inhibition of ADOM. In addition, based on the composition of coprecipitates and relatively biodegradable character of tryptophan-like substances (C2-ADOM), the coprecipitation of ADOM was assumed to reduce the stability of precipitated P in eutrophic lakes. The release of P from the potential biodegradation of the coprecipitates and thus the possible decline of the performance of P immobilization by La/Al-based treatments is an important work in the future.

Particulate organic matter (POM) significantly affects the distribution of heavy metals in contaminated soil. However, the effect of POM on the fate of heavy metals during in situ-aided phytostabilization of waste slag is unclear. The objective of this study was to investigate the distributions of heavy metals such as Cu, Pb, Zn, and Cd in the POM fractions at a zinc smelting waste slag site under in situ-aided phytostabilization after five years. The results showed that the litters and residues of four plants―Arundo donax, Broussonetia papyrifera, Cryptomeria fortunei, and Robinia pseudoacacia―decomposed to form different POM size fractions. The percentage of the 0.05–0.25 mm POM size fraction was the highest, followed by the >1 mm and 0.5–1 mm POM size fractions, and that of the 0.25–0.5 mm POM size fraction was the lowest. The masses of POM derived from the four plants were in the following order: C. fortunei > B. papyrifera > A. donax > R. pseudoacacia. The contents, enrichment coefficients, and mass loads of heavy metals such as Cu, Pb, Zn, and Cd in the POM increased with decreasing POM size, and those in the 0.05–0.25 mm POM size fraction were the highest. The mass load of heavy metals in the POM occurred in the following order: Cu > Cd > Zn > Pb. The surfaces of the POM with coarser and smaller size fractions were smoother and rougher, respectively, and the smaller POM size fractions had larger specific surface areas. The main functional groups in the different POM size fractions were –COOH, –OH, CO, CC, C–H, Si–O, and –CH₃. The POM fractions played a significant role in determining the distribution of heavy metals in the revegetated waste slag. These findings have important implications for aided phytostabilization, which significantly influences the fate and speciation of heavy metals at the phytoremediation site.

The increased applications and production of graphene oxide (GO) make the necessity to study information on the interaction of GO with minerals. In this work, adsorption and desorption were used to study the reversibility of interaction between GO and goethite/kaolinite. Result showed that the pH value, ionic strength, and temperature had significant effects on the adsorption and desorption behavior of GO. Interaction force was stronger between GO and goethite than that of kaolinite. The interaction may be attributed to the electrostatic, hydrogen-bonding, and Lewis acid base interactions. The irreversible interaction between GO and minerals may be a main mechanism for the observed desorption hysteresis. These results are important for evaluating the fate and health risk of GO in the environment.