Phosphorus (P), an irreplaceable nutrient for all living organisms, is facing scarcity via phosphate resources. In this research, the effect of suitable additives and temperature on P and heavy metals speciation during sewage sludge (SS) thermochemical treatment was investigated. The results demonstrated that additives (CaO and MgO) could promote the conversion of non-apatite inorganic phosphorus (NAIP) to apatite phosphorus (AP). X-ray diffraction measurements indicated that the phosphorus mineral phase in sewage sludge ash (SSA) mainly was AP, with addition of MgO and CaO. Moreover, orthogonal testing revealed that the optimal molar ratio of Mg:Ca:P for P recovery as AP was 1:3.5:1 at 750 °C. Risk index results implied that the heavy metals in the phosphorus-enriched SSA have low potential ecological risk. Thermodynamic equilibrium calculations revealed that P reacted with the other metal ions was in the following order: Ca²⁺ > Mg²⁺ > Al³⁺ > Fe³⁺ > Zn²⁺ > K⁺. Graphical Abstract

Previous study found out that Chinese household have a higher awareness of environmental protection but less positive initiative to protect the environment. With the increasing Chinese income, higher education, and changing environment state, public awareness and behavior on environment protection are changing. This paper tries to find out the current public willingness to participate in environment protection, by using the latest data from China Household Finance Survey (CHFS) which is investigated in 2017 that covered 31 provinces with a sample of more than 40 thousand households. Besides, logit regression model is adopted to find out the impact of pollution and household demographic on environment protection behavior. The results show that around 71.6% of surveyed households have willingness to pay for the environment protection. Rural residents and higher educated individuals are more likely to participate in environment protection. However, things are different if they face different degrees of pollution. Results can be explained with China’s current economic situation and would have some implications for future study on China’s public willingness to pay for the environment.

Emerging economies are experiencing considerable economic changes due to change in energy demand and CO₂ emissions. To explore the link between energy demand and CO₂ emissions, this study disaggregates energy consumption into renewable and nonrenewable, and investigates its impact on carbon (CO₂) emissions by incorporating the role of trade openness using the environment Kuznets curve (EKC) framework. Emerging economies from 1990 to 2015 are examined based on Morgan Stanley Capital International’s (MSCI’s) classification. This empirical study uses cross-sectional dependence (CD) test and second-generation panel unit root test for precise estimation. The Pedroni and Westerlund panel cointegration tests are used to examine the long-run equilibrium. Continuously updated fully modified (CUP-FM) and continuously updated bias-corrected (CUP-BC) approaches are applied to investigate long-run output elasticities while the vector error correction model (VECM) is used to examine the direction of causal relationships among the variables. The results show that renewable energy consumption affects the CO₂ emissions negatively while nonrenewable energy consumption positively impacts the CO₂ emissions. The study also supports the EKC hypothesis. Trade openness adversely affects the CO₂ emissions which are an imperative inclination of these economies towards globalization. Moreover, in the long run, energy consumption from renewable energy and economic growth Granger cause CO₂ emission, nonrenewable energy, and trade openness. In the short run, renewable energy Granger causes economic growth, while economic growth Granger causes nonrenewable energy. The study offers some vital policy suggestions for these emerging economies and some interesting lessons for the developing economies.

In this study, we analyzed the concentrations of metals in sediments and Corbicula fluminea in China’s Dongting Lake to assess the suitability of C. fluminea as an effective biomonitor of metal contamination in sediments and food safety. We analyzed the biota-accumulation capacity by calculating the biota-sediment accumulation factor (BSAF) and assessed the potential human health risk of metals exposure via consumption of C. fluminea using the target hazard quotient (THQ) and total target hazard quotient (TTHQ). The results showed that the average concentrations of As (31.93 mg kg⁻¹), Cd (5.54 mg kg⁻¹), Cr (105.50 mg kg⁻¹), Cu (32.53 mg kg⁻¹), and Zn (207.89 mg kg⁻¹) in sediments were higher than their respective standard set by the General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China. The sediment metals, which were mainly anthropogenic in origin, were at high levels and pose a relatively high ecological risk. Cadium (Cd) showed very high potential ecological risk levels and should be included in the prior pollutants list in the studied area. The mean levels of As (0.81 mg kg⁻¹) in C. fluminea were 1.62-times higher than that set by the National Health Commission of the People’s Republic of China. BSAF values of the soft tissues of C. fluminea were between 0.05 and 2.14, with higher values for Cu (2.14), Cd (1.77), Zn (1.60), and Ni (1.27). Soft tissues of C. fluminea were able to reflect spatial differences in Sr within sediments around Dongting Lake. The results indicated that C. fluminea could be an potential biomonitor for sediment metals assessment in biomonitoring programs, especially for Cu, Cd, Zn, Ni, and Sr. The mean values for THQ and TTHQ of all the analyzed metals were below 1.0, indicating that the intake of metals via comsumption of C. fluminea does not result in an appreciable risk to human health.

The irrigation with sewage water can be useful if it has no negative effects on food crop yield, soil pollution, and health of humans. However, it includes various types of contaminants like heavy metals that pollute the soil and crops. In this regard, the aim of this study was to evaluate the possible health risks of heavy metals in forages. Forages both of summer and winter were grown with different water treatments (sewage water and tap water) in Department of Botany, University of Sargodha. The concentration of iron (Fe) in water, soil, and plant samples was determined. The Fe values in tap and sewage water were observed as 0.090 and 0.115 mg/L, respectively. The highest mean concentration of Fe was 9.608 mg/kg in the soil where Trifolium alexandrinum is grown, and the lowest mean concentration was 0.154 mg/kg which occurred in the soil where Trifolium resupinatum is grown in winter. The maximum mean concentration of Fe in the root samples of plants was observed as 2.483 mg/kg in Pennisetum typhoideum, and the minimum mean concentration occurred as 0.390 mg/kg in Zea mays grown in summer. The maximum bioconcentration factor value of Fe was observed for T. resupinatum (5.259) grown in winter. The maximum pollution load index value of Fe was observed for T. alexandrinum (0.1688). The maximum value of daily intake of metals was observed as 0.0731 in Medicago sativa, and the maximum health risk index value was determined as 0.1091 in P. typhoideum.

To determine the concentration of particulate matters (PM₂.₅ and PM₁₀), 36 samples were collected from indoor/outdoor air of hookah cafés (HS), cigarette cafés (CS), both hookah and cigarette (HCS), and no-smoking building (NS) in Tehran City from December 2017 to March 2018. The mean ± SD of PM₁₀ concentration in the indoor air of the cafés in terms of HS, CS, HCS, and NS sites has been 702.35, 220.20, 1156.60, and 60.12 μg/m³, while for PM₂.₅, the values have been 271.92, 111.80, 619.10, and 22.25 μg/m³, respectively. It was also found that the PM concentration inside the cafés was higher during weekend session (with a higher number of active smokers), than during the weekday sessions. Moreover, the PM levels in the indoor air of the cafés were considerably higher than those of the outdoors (p < 0.05). Based on path analysis, the number of “active smokers” had the highest influence on production of PM inside the cafés, followed by the tobacco type. Finally, the mean excess lifetime cancer risk (ELCR) for PM₂.₅ in the indoor air of cafés was observed in the range of 0.64 × 10⁻⁵–14.98 × 10⁻⁵. Also, the mean of hazard quotient (HQ) for PM2.5 and PM₁₀ was calculated in range of 0.82–18.4 and 0.16–3.28, respectively, which corresponds to an unacceptably high risk for human health. The PM levels in the indoor air of smoking cafés in Tehran are significantly high, such that it can cause serious risks for the health of both the customers and personnel. Thus, it is necessary that suitable controlling strategies be adopted for this public health threat.

The synergistic effects of trace elements selenium (Se) and cadmium (Cd) are well known. But the reasons for the trending accumulation behavior in both trace elements are under debate in the scientific community. The present investigation was conducted to evaluate the impact of heat units on the accumulation behavior in two environments. Se and Cd were applied in three groups (T₀; 0:0, T₁; 0.4:1, T₂; 1:2) mg kg⁻¹. As the time of planting and heat units consumed by the crop to attain its physiological maturity appears to be different. The sunlight may contribute as an important manipulating factor for the accumulation of heavy metals in the plant. The results of the present study indicated that the behavior in the accumulation pattern of both elements appears to be distinct in the same material. The increased fertilizer treatment in soil bulk linearly increased the metal contents in rice grain. The studies between different plant parts disclosed panicle as the primary reservoir for Se and Cd accumulation. The plant sown earlier accumulates more Se than Cd while the plants uptake more Cd when sown 1 month later. The plant completes the critical developmental phases (tillering, heading, and flowering) within 20–30 days interval depending on the variety. But the late-sown plants complete these transitional phases within 9–10 days interval ultimately result in less utilization of heat units. These quick transitional changes may lead to the uptake of an ample amount of Cd contents in rice grain even at a low level of Cd stress (1 and 2 mg kg⁻¹), making rice unsafe for edible purposes. The proper time of planting could be effective in timely acclimatization of Se and Cd sequestration and translocation in rice various components. Graphical Abstract

The Loess Plateau is the most severely degraded soil area worldwide and represents one of the lowest areas of soil productivity. To solve the conundrum between increasing populations and decreasing agricultural acreage, enhancing the quantity of cultivated land, gully land consolidation projects has been implemented. However, the new creation farmland soil is not enough to satisfy the demand of agricultural production. An incubation experiment was conducted to determine the effects of biochar on the new creation farmland soil. Five levels of amendments (0, 1%, 2%, 5%, and 10% (wt%) biochar soil) were used, and the soil columns remained in the laboratory for approximately 2 months. The results show that biochar proportion was a more important factor than incubation time across all soils tested. The soil moisture content and particle size clearly increased as the amendment level increased; however, the soil pH decreased gradually with incubation time and tended to slow soil salinization. These findings will have to be verified under field conditions.

In this study, the long-term operational performance of an on-site NF facility at a full-scale oil-field wastewater desalination plant was monitored. The NF facility with poor permeability due to membrane fouling enables efficient multivalent salt removal (rejections of Mg²⁺, Ca²⁺, Fe³⁺, and Al³⁺ were approximately 100%). Moreover, a comparison of the cleaning efficiencies of two on-site cleaning modes indicated that PL-007 cleaning helped to improve the effectiveness of subsequent acid cleaning in the removal of inorganic foulants. Furthermore, a spiral-wound NF membrane module harvested from the plant was unfolded and autopsied. The results showed that both anionic polyacrylamide (APAM) and crude oil were identified as the predominant organic matter on the membrane surface and collectively accounted for a substantial fraction (86.3%) in terms of dry weight. Additionally, dissolved organics with a high molecular weight were prone to accumulation on the membrane surface. Multivalent elements, including Mg, Ca, Al, Fe, and Si, were the primary inorganic species in the fouling layer. Among the inorganic elements, Si occupied a high proportion and existed in the form of SiO₂ in the fouling layer. According to the autopsy results, organic fouling combined with inorganics was responsible for the decline in the flux.

In this presented study, it was aimed to determine the effects of pesticides on non-target organisms on the freshwater amphipod, Gammarus pulex, by biochemical responses. Acute toxicity value (LC₅₀) in G. pulex of the dimethoate pesticide was determined. The superoxide dismutase (SOD), glutathione S-transferaz (GST), glutathione peroxidase (GPx), and catalase (CAT) activities and malondialdehyde (MDA), glutathione (GSH) levels of the G. pulex organism exposed to the subletal concentrations were analyzed by ELISA for 24 and 96 h. In conclusion, the present study demonstrated the abilities of dimethoate pesticide induce to oxidative stress. The results revealed that MDA, GSH levels SOD, CAT, GPx, and GST activities of G. pulex can be used as an effective biomarkers.