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Heavy metals in soils pose serious ecological and health risks. To make efficient strategies for mitigating the underlying hazards, it is critical to reveal the pollution sources and their links with the risks. Researchers have investigated source identification and risk evaluation of heavy metals in soils, yet few have systematically deciphered the source-sink relationship of soil metals and the links between source apportionment and risk assessment. In the study, an integrated technological framework has been proposed to address the gaps, and applied to characterize the pollution risks, sources and their links of soil metals in a typical coal resource city in China. The assessment using geochemical tool and ecological risk index shows the soils in study area are polluted by Cd, Hg, Cr, As and Pb in varied degrees, and particularly, Cd and Hg present significant ecological risk. Two advanced receptor models (multivariate curve resolution-weighted alternating least-squares and multilinear engine 2) are comparatively applied for apportioning the potential sources of soil metals, and the results suggest the two models have identified similar sources (r2 > 0.90), including agricultural activities, atmospheric depositions and industrial discharges with contributions of 35.5 %-38.3 %, 30.3 %-35.1 %, and 26.6 %-34.1 %, respectively. Then, apportionment results of the two models are jointly employed for evaluating the source-specific health risks of metals in the environment using a probabilistic risk assessment model. The risk levels within the area are overall acceptable or tolerable, and relatively, the industrial discharges present higher contribution on the non-carcinogenic and carcinogenic risks of soil metals to public. Findings will help the managers to design targeted policies for reducing the risks of soil metals, and the framework proposed provides a useful guideline to better understand the source-risk relationship of soil metals in other environments worldwide.

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In 2018, China implemented the Veterinary Antimicrobial Use Reduction Action to curb the rapid development of antibiotic resistance (AR). However, the AR-related pollutions in animal farms after the reduction policy has been poorly investigated. Here, we performed a comprehensive investigation combining UPLC-MS/MS, metagenomic, and bacterial genomic analyses in eight representative large-scale chicken farms in Guangdong, China. Our results showed that antibiotics and ARGs contaminations were more severe in broiler farms than in layer farms. Notably, diverse tet(X) variants were prevalent in the chicken farms. These tet(X)s was carried by diverse E. coli lineages and obviously correlated with ISCR2 and IS1B transposases. The resistomes in chicken farms was significantly correlated with microbial community, and multiple factor analyses indicated that the joint effect of antibiotics-microbial community-MGEs was the most dominant driver of ARGs. Host tracking identified a variety of ARG bacterial hosts and the co-occurrence of ARGs-MRGs-MGEs. Source tracking indicated that the inherent component represented the main feature of resistomes in different hosts, while ARG transfer between the chicken gut and farm environments were frequent. A multiperspective evaluation of AR risk revealed that the early effect of antibiotic reduction was exhibited by the mitigation of maximum level of risky ARGs, prevalence of environmental AR pathogens, and HGT potential of ARGs mediated by phage structures. Overall, our findings provide insights into the antibiotic and ARG profiles in large-scale chicken farms with different rearing strategies and demonstrate a preliminary view of the performance of antibiotic reduction actions in China.

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Pyrolysis stands out as an effective method for the disposal of phytoremediation residues in abandoned mines, yielding a valuable by-product, biochar. However, the environmental application of biochar derived from such residues is limited by the potential environmental risks of heavy metals. Herein, Miscanthus sp. residues from abandoned mines were pyrolyzed into biochars at varied pyrolysis temperatures (300-700 °C) to facilitate the safe reuse of phytoremediation residues. The results showed that pyrolysis significantly stabilizes heavy metals in biomass, with Cd exhibiting the most notable stabilization effect. Acid-soluble/exchangeable and reducible fractions of Cd decreased significantly from 69.91 % to 2.52 %, and oxidizable and residue fractions increased approximately 3.24 times at 700 °C. The environmental risk assessment indicated that biochar pyrolyzed over 500 °C pose lower environmental risk (RI < 30), making them optimal for the safe utilization of phytoremediation residues. Additionally, adsorption experiments suggested that biochars prepared at higher temperature (500-700 °C) exhibit superior adsorption capacity, attributed to alkalinity and precipitation effect. This study highlights that biochars produced by pyrolyzing Miscanthus sp. from abandoned mines above 500 °C hold promise for environmental remediation, offering novel insight into the reutilization of metal-rich biomass.

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In the European Medicines Agency (EMA) "Guideline for Environmental Risk Assessment of Medicinal Products for Human Use," a fish bioconcentration factor (BCF) study is triggered in Phase I for pharmaceuticals having log Kow >4.5, to support Persistence, Bioaccumulation and Toxicity (PBT) screening, and in Phase II to assess secondary poisoning and bioaccumulation ('B') potential when log Kow ≥3. The standard sampling schedule outlined in OECD Test Guideline 305 (TG305) may require assessment of approximately 200 fish following exposure to low- and high-test concentrations and a negative control. We report experimental log Kow and BCF values for 64 human pharmaceuticals that were used to evaluate the current BCF testing trigger of log Kow ≥3, and whether a single BCF exposure concentration allows accurate classification of bioaccumulation potential. Our data support raising the BCF testing trigger to log Kow ≥4, and use of a single test concentration. The resulting reduction in the use of fish is consistent with the 3 R s principle and did not adversely affect classification accuracy. An assessment of potential risk of secondary poisoning was also conducted for three drugs classified as either B or vB, and no risks were identified.

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This study focuses on the diffusion patterns of principal ore-forming elements (Pb and Zn) and associated elements (Cd, Cu, Cr, and As) in lead-zinc ore. Sampling points in upwind and downwind directions of lead-zinc ore areas at various densities (1 N/km2 - 4 N/km2) were categorized. This study analyzed the statistical relationship between the content of PTEs in the soil around lead-zinc ore and the source strength and dominant wind direction, constructed one-dimensional and two-dimensional diffusion model, and simulated the EER scope caused by PTEs. The findings indicate that: (1) concerning source strength, the content of PTEs in soils of high-density ore aggregation areas is significantly higher than in low-density ore aggregation areas. However, the impact of source strength decreases with decreasing ore grade, with a difference in Pb content of 1.71 times among principal ore-forming elements and almost consistent Cd content among associated elements. (2) Regarding the transport pathways, for most PTEs, the inverse proportion coefficients downwind are higher than upwind, approximately 1.18-3.63 times, indicating greater migration distances of PTEs downwind due to atmospheric dispersion. (3) By establishing a two-dimensional risk diffusion model, the study simulates the maximum radius of risk diffusion (r = 5.7 km), the 50% probability radius (r = 3.1 km), and the minimum radius (r = 0.8 km) based on the maximum, median, and minimum values statistically obtained from the EER. This study provides a scientific basis for implementing preventive measures for PTEs accumulation in soil within different pollution ranges. Different risk prevention and control measures should be adopted for PTEs accumulation in soil within the three ranges after cutting off pollution sources. Subsequent research should further investigate the impact and contribution of atmospheric transmission and surface runoff on the diffusion of PTEs in areas with high risk near lead-zinc ore.

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Carbon:nitrogen:phosphorus (C:N:P) stoichiometry plays a vital role in regulating P transformation in agriculture ecosystems. However, the impact of balanced C:N:P stoichiometry in paddy soil, particularly regarding relative soil P transformation, remains unknown. This study explores the response of C:N:P stoichiometry to manure substitution and its regulatory role in soil P transformation, along with the associated release risk to the environment. Based on a 5-year field study, our findings reveal that replacing 30 % of chemical P fertilizer with pig manure (equal total NPK amounts with chemical P fertilizer treatment, named CFM) increased soil total C without altering soil total P, resulting in an elevated soil C:P ratio, despite the homeostasis of crop stoichiometry. This increase promoted microbial diversity and the accumulation of organic P in the soil. The Proteobacteria and Actinobacteria produced lower C:PEEA metabolism together, and enhanced in vivo turnover of P. Additionally, by integrating high-resolution dialysis (HR-Peeper), diffusive gradients in thin films (DGT), DGT-induced fluxes in the soil (DIFS), and sediment P release risk index (SPRRI) models, we observed that, in addition to organic P, CFM simultaneously increased soil Al-P, thereby weakening the diffusion and resupply capacity of P from soil solids to the solution. Consequently, this decrease in P release risk to the environment was demonstrated. Overall, this study establishes a connection between crop-soil-enzyme C:N:P stoichiometry, soil microorganisms, and soil P biogeochemical processes. The study further evaluates the P release risk to the environment, providing a novel perspective on both the direct and indirect effects of manure substitution on soil P cycling.

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Volatile organic compounds (VOCs) are ubiquitous in both indoor and outdoor environments. Evidence on the associations of individual and joint VOC exposure with all-cause and cause-specific mortality is limited. Measurements of 15 urinary VOC metabolites were available to estimate exposure to 12 VOCs in the National Health and Nutritional Examination Survey (NHANES) 2005-2006 and 2011-2018. The environment risk score (ERS) was calculated using LASSO regression to reflect joint exposure to VOCs. Follow-up data on death were obtained from the NHANES Public-Use Linked Mortality File through December 31, 2019. Cox proportional hazard models and restricted cubic spline models were applied to evaluate the associations of individual and joint VOC exposures with all-cause and cause-specific mortality. Population attributable fractions were calculated to assess the death burden attributable to VOC exposure. During a median follow-up of 6.17 years, 734 (8.34 %) deaths occurred among 8799 adults. Urinary metabolites of acrolein, acrylonitrile, 1,3-butadiene, and ethylbenzene/styrene were significantly associated with all-cause, cardiovascular disease (CVD), respiratory disease (RD), and cancer mortality in a linear dose-response manner. Linear and robust dose-response relationships were also observed between ERS and all-cause and cause-specific mortality. Each 1-unit increase in ERS was associated with a 33.6 %, 39.1 %, 109.8 %, and 67.8 % increase for all-cause, CVD, RD, and cancer mortality risk, respectively. Moreover, joint exposure to VOCs contributed to 17.95 % of all-cause deaths, 13.49 % of CVD deaths, 35.65 % of RD deaths, and 33.85 % of cancer deaths. Individual and joint exposure to VOCs may enhance the risk of all-cause and cause-specific mortality. Reducing exposure to VOCs may alleviate the all-cause and cause-specific death burden.

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Antibiotics are emerging pollutants that have detrimental effects on both target and non-target organisms in the environment. However, current methods for environmental risk assessment primarily focus on the risk to non-target organisms in ecosystems, overlooking a crucial risk of antibiotics - the induction of resistance in targeted bacteria. To address this oversight, we have incorporated resistance (R) risk with persistence, bioaccumulation and toxicity (PBT) to establish a more comprehensive PBTR (persistence, bioaccumulation, toxicity, and resistance) framework for antibiotic-specific risk assessment. Using the PBTR framework, we evaluated 74 antibiotics detected in Chinese seawater from 2000 to 2021, and identified priority antibiotics. Our analysis revealed that the priority antibiotics with R risk accounted for the largest proportion (50% to 70%), followed by P risk (40% to 58%), T risk (16% to 35%) and B risk (0 to 13%). To further categorize these priority antibiotics, we assigned them a risk level according to their fulfillment of criteria related to P, B, T, and R. Antibiotics meeting all four indicators were classified as Grade I, representing the highest risk level. Grade II and Grade III were assigned to antibiotics meeting three or two indicators, respectively. Antibiotics meeting only one indicator were classified as Grade IV, representing the lowest risk level. The majority of priority antibiotics fell into Grade IV, indicating low risk (55% to 79%), followed by Grade III (16% to 45%). The highest risk antibiotic identified in this study was clindamycin (CLIN), categorized as Grade II, in the East China Sea. Our findings aligned with previous studies for 25 antibiotics, affirming the validity of the PBTR framework. Moreover, we identified 13 new priority antibiotics, highlighting the advancement of this approach. This study provides a feasible screening strategy and monitoring recommendations for priority antibiotics in Chinese seawater.

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OBJECTIVE: This study aimed to evaluate the association between urinary heavy metal mixture exposure and depression, and the modifying role of physical activity in the effects of heavy metal mixture on depression risk was also considered. METHODS: Data of this study were derived from the National Health and Nutrition Examination Survey 2011-2016. Depression was measured by the Patient Health Questionnaire. We first selected 6 (cadmium, cobalt, tin, antimony, thallium, and mercury) from 14 heavy metals through elastic net regression for further analysis. Then binomial logistic regression, generalized additive model, environment risk score (ERS), and weighted quantile sum (WQS) regression were adopted to assess the effects of six metals individual and cumulative exposure on depression risk. Finally, we also examined whether physical activity could mitigate the effects of heavy metal co-exposure on depression risk. RESULTS: Totally, 4212 participants were included and 7.40% of subjects were with depression. We found urinary tin and antimony were separately associated with increased odds of depression (Sb: OR = 1.285, 95% CI: 1.064-1.553; Sn: OR = 1.281, 95% CI: 1.097-1.495), and a linear dose-response relationship between tin and depression was also noticed (P < 0.05). Meanwhile, urinary heavy metals co-exposure was positively related to depression risk (ERSQ4: OR = 2.691, 95% CI: 1.399-5.174; WQSpositive: OR = 1.465, 95% CI: 1.063-2.021), in which tin, antimony, and cadmium were identified with greater contributions to the overall mixture effect. In both ERS and WQS models, the significant positive association between the metal mixture and depression risk remained only in those who were inactive in physical activity. CONCLUSION: Our study concluded the detrimental effect of heavy metals in combined exposure on the risk of depression, which might be attenuated by physical activity.

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COVID-19 has disrupted all spheres of life, including country risk regarding the exposure of economies to multi-dimensional risk drivers. However, it remains unexplored how COVID-19 has impacted different drivers of country risk in a probabilistic network setting. This paper uses two datasets on country-level COVID-19 and country risks to explore dependencies among associated drivers using a Bayesian Belief Network model. The drivers of COVID-19 risk, considered in this paper, are hazard and exposure, vulnerability and lack of coping capacity, whereas country risk drivers are economic, financing, political, business environment and commercial risks. The results show that business environment risk is significantly influenced by COVID-19 risk, whereas commercial risk (demand disruptions) is the least important factor driving COVID-19 and country risks. Further, country risk is mainly influenced by financing, political and economic risks. The contribution of this study is to explore the impact of various drivers associated with the country-level COVID-19 and country risks in a unified probabilistic network setting, which can help policy-makers prioritize drivers for managing the two risks.

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In modern society, law is one of the most important means of risk prevention and control. Under the challenge of ecological and environmental risks, China's legal governance experience provides important historical experience and theoretical samples for other countries. Faced with problems, such as the difficulty of eliminating risks, risk decisions themselves bring risks, and the huge social cost of risk response, the social system theory can provide novel and new ideas for the cognition and response of environmental risks. Combining the experience of judicial practice with social theory, especially Niklas Luhmann's doctrine of the risk/danger dichotomy, a clearer functional orientation can be given to judicial powers based on risk communication and risk attribution. By reviewing the ecological judicial practices in China, Germany, and other countries, the role of the legal system in stabilizing the normative expectations of the whole of society can be summarized, which will provide a reference for the risk response and legal governance of the global ecological environment.

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In response to the economic and social hazards posed by the COVID-19 global pandemic, many countries have adopted various information technologies to rapidly track and control the spread of the epidemic. Health Quick Response (QR) codes are emergency measures implemented by the Chinese government in the epidemic environment to balance epidemic prevention and control with recovery of economic and social development, and facilitate public mobility across regions and access to various public spaces. The use of health codes by the public is a practical necessity, but the satisfaction of their use is influenced by multiple factors such as environment, technology, and organization. In this paper, we collected data through a questionnaire to analyze the basic situation of public satisfaction with the use of health QR codes in China and its influencing factors. The results show that perceived quality and platform trust directly affect the satisfaction of health code usage, while environmental risk and platform trust indirectly affect the satisfaction of health code usage through the mediating effect of perceived quality.

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The study examined the effects of swimming pools on healthcare professionals' willingness to engage in recreational activities, physical anxiety, and physical and mental well-being in the context of COVID-19. The research adopted the mixed research method, used SPSS 26.0 statistical software to test the reliability of the questionnaire, and then collected 840 valid questionnaires; first analyzed the data with basic statistics, t-test, ANOVA, and PPMCC test methods, and then used the interview method to collect expert opinions. A multi-check approach assembled all data and discussions. The study found that the use of personnel dynamic tracking systems or measures, combined with sodium hypochlorite and repeated filtration to stabilize water quality, could maintain the confidence of most medical workers in the swimming pool sports environment for epidemic prevention and avoid violations. The government could formulate safety prevention and control mechanisms in traffic and establish appropriate traffic routes. Next, formulated a prescription for swimming or other physical activity mechanisms for men aged 31-50 and redesigned measures for medical staff over 51 years old to have tense head issues and physical fatigue, promote blood circulation and improve sleep quality. This will promote the purpose of relieving stress and regulating the physical and mental health of medical staff after engaging in swimming.

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The study was conducted to assess the impacts of Cai Dau and An Cu landfills in An Giang province, Vietnam on soil quality using relative soil quality index (RSQI), potential ecological risk index (PERI), and multivariable statistical methods and associated health risks. Forty-eight soil samples were collected in two layers: A (0-20 cm) and B (60-80 cm) and analyzed for five physiochemical soil parameters and eight heavy metals during the rainy and dry seasons. The results showed that pH fluctuated from weak acid to neutral, and organic matters and nutrients in soil were from poor to moderate. Heavy metal concentrations were within the Vietnamese standards. The concentrations of the soil quality parameters tended to be higher during the rainy season at the Cai Dau landfill, but lower at the An Cu landfill. The RSQI was rated as bad to good and hazardous to bad at the Cai Dau and An Cu landfills, respectively. The principal component analysis (PCA) and absolute principal component score-multiple linear regression analysis demonstrated the contribution of landfill and agricultural impacts to soil quality variability, accounting for 81.38-90.64 %. Landfills contributed greater 35 % and 50 % to heavy metal contents at Cai Dau and An Cu, respectively. The heavy metal accumulation at Cai Dau landfill was in the decreasing order of Ni > Cr > As, but that was not found at An Cu landfill. The pollution load index (PLI) indicated medium and low risks of heavy metal contamination at the Cai Dau and An Cu landfills, respectively, thus posing low potential ecological risk. The non-cancer and cancer risks of heavy metals-contaminated soil were at acceptable level. Monitoring of heavy metals in the environments surrounding landfills is needed due to its accumulative characteristics.

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Fipronil is a broad potent insecticide that belongs to the phenylpyrazole chemical family. Its action mode acting in the presynaptic and postsynaptic blocking the chlorine ions by the neurotransmitters GABA. It is considered highly toxic, and in some countries, its use has been prohibited. The objective of this review is to perform a scientometric analysis for global measurement of the research on the insecticide fipronil. All information in this study was searched in the Web of Science (WoS) database in December 2021. The search was carried using the term "fipronil." Thus, 2362 studies were selected. Most selected articles showed toxicity effects of fipronil on non-target organisms, analytical methods to detect the insecticide, environmental degradation processes, and efficiency in reducing insects through its use. The H index for this dataset was 91. The cooperation network of the authors among countries showed the USA as the most notorious, with 30.6% of studies, followed by China (15.7%) and Brazil (10.9%). There are many studies on the toxicity of fipronil in bees, forms of degradation, and effectiveness of this insecticide. The present work presents suggestions pointed out in the articles for further research and highlights the importance of studies involving fipronil, as well as studies of alternative pest control.

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Water security is a compound concept coupling multi-dimensional perspectives, such as resource utilization, environmental protection, and disaster prevention. With this concern, this study focuses on the spatial-temporal dynamics of water security with considering water disaster risk index (WDRI), water environment risk index (WERI), and water supply-demand. WERI centers on risk source's hazard, control effectiveness, and risk receptor's vulnerability. Indices related to hazard, exposure, and vulnerability are used for evaluating WDRI. A multi-objective fuzzy membership function is presented for determining the indices' weight, and the distribution pattern of water security is illustrated based on cluster analysis. A real-world case study of Beijing-Tianjin-Hebei urban agglomeration (BTHUA) is given for verifying availability of the evaluation framework. Results indicate the general water security in BTHUA with a critical safe state yet a downward trend. Opposite change characteristics of water security exist between its southern and northern cities. WDRI and WERI show the trends of increasing (with a growth rate of 0.48%) and decline (with an average decrement rate of 0.56%), respectively. Beijing has high-value WDRI and WERI, and the order of WDRI and WERI is presented as follows: Beijing (0.67) > Tianjin (0.54) > Hebei (0.33) and Beijing (0.69) > Tianjin (0.58) > Hebei (0.16), respectively. Cluster analysis reveals a poor match relation between water security and regional socio-economic development. Areas with high-level economic development (e.g., Beijing and Tianjin) have poor environmental performances, with WDRI and WERI of 0.54 ~ 0.68 and 0.57 ~ 0.70, respectively. Additionally, water resources overload index of BTHUA is 8.513, which is higher than Chengdu-Chongqing urban agglomeration (1.431), Triangle of Central China (0.228), and Yangtze River Delta urban agglomeration (0.742). Findings can provide a theoretical reference for promoting sustainable utilization of water resources in BTHUA and the other areas with prominent water problems.

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Trace elements contamination is mainly originated from industrial emission, sewage irrigation and pesticides, and poses a threat to the environment and human health. This study analyzed the trace element pollutants in peanut-soil systems, the enrichment and translocation capacity of peanut to trace elements, and the potential risk of trace elements to environment and human health. The results indicated that Cd and Ni in peanut kernels exceeded the standard limits in 2019, and the exceeding rate were 9% and 31%, respectively. Cd in 8% of soil samples and As in 98% of soil samples exceeded the risk screening value of trace elements. The concentration of trace elements in peanuts was related to varieties and planting regions. In addition, there was a significant positive correlation between the concentration of Cd in peanut kernel and its concentration in soil. Compared with other trace elements, peanut kernels had stronger ability to enrich and transport Cd, Cu, and Zn, the BFs were 0.45, 0.51 and 0.47, respectively. After oil extraction, trace elements were mainly concentrated in peanut meal, and only 0.25% of Cd was in oil. The RI of trace elements was less than 150, indicating that the study area was under low degree of ecological risk. However, As and Cd might pose moderate risk to environment. Trace elements in soil and peanut could not cause non-carcinogenic and carcinogenic risks to human, but the HI and CR value of As (0.59 and 9.54 × 10-5) in soil and CRing value of Cd (9.25 × 10-7) in peanut were close to the critical value. We conclude that Cd pollution in peanut kernel, and Cd and As pollution in soil should be monitored to enter into the food chain or environment and to avoid the possible health hazards and environment risks.

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BACKGROUND: While chronic workplace stress is known to be associated with health-related outcomes like mental and cardiovascular diseases, research about day-to-day occupational stress is limited. This systematic review includes studies assessing stress exposures as work environment risk factors and stress outcomes, measured via self-perceived questionnaires and physiological stress detection. These measures needed to be assessed repeatedly or continuously via Ecological Momentary Assessment (EMA) or similar methods carried out in real-world work environments, to be included in this review. The objective was to identify work environment risk factors causing day-to-day stress. METHODS: The search strategies were applied in seven databases resulting in 11833 records after deduplication, of which 41 studies were included in a qualitative synthesis. Associations were evaluated by correlational analyses. RESULTS: The most commonly measured work environment risk factor was work intensity, while stress was most often framed as an affective response. Measures from these two dimensions were also most frequently correlated with each other and most of their correlation coefficients were statistically significant, making work intensity a major risk factor for day-to-day workplace stress. CONCLUSIONS: This review reveals a diversity in methodological approaches in data collection and data analysis. More studies combining self-perceived stress exposures and outcomes with physiological measures are warranted.

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Overuse of phosphorus (P) fertilizer and the resulting soil P accumulation in vegetable production increases the risk of P runoff and leaching. However, P transformations under continuous fertilization and their effects on environmental risk are unclear. The current study examined the effects of long-term P fertilizer application on P fractions in different soil layers, and assessed the correlations between P fractions and environmental risks in intensive vegetable production in a subtropical region. A total of 32 fields were studied, including 8 uncultivated fields and 24 fields continuously used for vegetable production for 1-3, 4-9, or 10-15 years. The results showed that excessive P fertilizer input caused soil P surpluses ranging from 204.6 to 252.4 kg ha-1 yr-1. Compared to uncultivated fields, vegetable fields contained higher levels of labile P, moderately labile P, sparingly labile P, and non-labile P. The combined percentage of labile P and moderately labile P increased from 55.2% in fields cultivated for 0-3 year to 65.5% in fields cultivated for 10-15 years. The concentrations of soil P fractions were higher at 0-20 cm soil depth than at 20-40 and 40-60 cm soil depth. Soil available P was positively correlated with all soil P fractions except diluted HCl-Pi or concentrated HCl-Po. Long-term vegetable production increased CaCl2-P downward movement, which was positively correlated with levels of labile and moderately labile P. The P index indicated a high risk of P losses from the vegetable fields. The P index was on average 3.27-fold higher in the vegetable fields than in uncultivated fields, and was significantly correlated with soil available P and organic and inorganic P fertilizer input. The environmental risk caused by P in vegetable production should be reduced by reducing P fertilizer input so as to maintain soil available P within an optimal range for vegetable production.

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Uranium-enriched coal ash (CA) receives a significant attention as a supplementary nuclear resource also due to its potential environmental risk. Combining with CA, the changing trend of uranium occurrence in synthetic coal ash (SCA) was described at CaO-Al2O3-Fe2O3 ternary phase diagrams with a fixed SiO2 (wt. %, 30%, 50% and 70%) and Na2O (2%) content. This study reveals that the mode of uranium occurrence proposes a three-stage changing process during coal combustion including uranium oxidation, combination and encapsulation. Furthermore, a high frequency of encapsulated uranium resulted from the complicated interactions among major components with a medium SiO2 content, whereas the degree was higher at a higher SiO2, resulting in the decrease of uranium mobility. Uranium was encapsulated by Si-Al matrix and Fe-Si depletion if provided the high Al2O3 and Fe2O3 but low CaO contents. However, with the development of calcium looping and biomass co-firing process, the change of element mobility should be considered in industry owing to the extra-added alkaline metals. As the activation of Ca2+ induces a significant susceptibility of acid attack, cautions must be paid in CA with a higher Ca/Si ratio to avoid its utilization as constructive materials for the potential environmental risk.