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In the storage of hazardous chemicals, due to space limitations, various hazardous chemicals are usually mixed stored when their chemical properties do not conflict. In a fire or other accidents during storage, the emergency response includes two key steps: first, using fire extinguishers like dry powder and carbon dioxide to extinguish the burning hazardous chemicals. In addition, hazardous chemicals around the accident site are often watered to cool down to prevent the spread of the fire. But both the water and extinguishers may react chemically with hazardous chemicals at the accident site, potentially triggering secondary accidents. However, the existing research about hazardous chemical domino accidents only focuses on the pre-rescue stage and ignores the simulation of rescue-induced accidents that occur after rescue. Aiming at the problem, a quantitative representation algorithm for the spatial correlation of hazardous chemicals is first proposed to enhance the understanding of their spatial relationships. Subsequently, a graph neural network is introduced to simulate the evolution process of hazardous chemical cascade accidents. By aggregating the physical and chemical characteristics, the initial accident information of nodes, and bi-temporal node status information, deep learning models have gained the ability to accurately predict node states, thereby improving the intelligent simulation of hazardous chemical accidents. The experimental results validated the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Objectives. This study conducted a comparative analysis of two catastrophic pipeline accidents in China in order to identify some common mistakes and lessons learned to prevent similar accidents. Methods. The 24Model was used in this study, which provides a universal pathway for accident analysis from the individual level to the organizational level. Results. There were similarities between the two cases in the aspects of the occurrence, development, emergency and causation at different levels: both were caused by leaks of pipelines and evolved into multiple explosions during emergency response; both leaks were caused by the corrosion of pipelines in the confined space of a damp or salt-spray environment; both were classified as 'responsibility accidents', and unsafe acts, such as the failure to identify hidden hazards of pipelines that were the direct cause of accidents, reflected the shortcomings of individual safety habitual behaviour in terms of knowledge, awareness, habits and psychology; weaknesses in the organizational management mainly concerned hazard identification, pipeline maintenance, emergency disposal, etc.; and there is not a good safety climate within the organization. Conclusions. Organizations should develop a closed-loop management system and strengthen the construction of safety culture, and the government should supervise the implementation of procedures. [ABSTRACT FROM AUTHOR]

The widespread use of hexabromocyclododecane (HBCD), a brominated flame retardant, is a major public health concern because of the toxic, persistent, and bioaccumulative nature of HBCD. However, there is limited information available regarding the distribution and transportation of HBCD in sediments across various environmental settings, spanning from riverine to marine environments in the Kaohsiung area of Taiwan. In this study, we comprehensively investigated the level and distribution of and potential ecological risk posed by HBCD in surface sediments in the Kaohsiung area of Taiwan. In sediment samples from stations on the Love River and Kaohsiung Port area, the concentrations of HBCD ranged from 10.6 to 320.1 μg/kg dry weight (dw) and nondetectable (n.d.) to 58.4 μg/kg dw, respectively. The concentrations of HBCD in sediment collected from the M1, M2, and M3 sites, located in the Cijin coastal area, were 896.2 μg/kg dw, 3.2 μg/kg dw ( 1. The M1 site had the highest risk level (RQ = 5.27). These data suggest that domestic sewage and industrial wastewater discharge pose a potential risk to marine environments. Consequently, timely measures to control HBCD-related risks are required. Our study offers insight into the environmental effects of HBCD contamination of sediment and provides valuable information that can be used to guide environmental policy and safety measures. [ABSTRACT FROM AUTHOR]

Human biomonitoring (HBM) data in Europe are often fragmented and collected in different EU countries and sampling periods. Exposure levels for children and adult women in Europe were evaluated over time. For the period 2000–2010, literature and aggregated data were collected in a harmonized way across studies. Between 2011–2012, biobanked samples from the DEMOCOPHES project were used. For 2014–2021, HBM data were generated within the HBM4EU Aligned Studies. Time patterns on internal exposure were evaluated visually and statistically using the 50th and 90th percentiles (P50/P90) for phthalates/DINCH and organophosphorus flame retardants (OPFRs) in children (5–12 years), and cadmium, bisphenols and polycyclic aromatic hydrocarbons (PAHs) in women (24–52 years). Restricted phthalate metabolites show decreasing patterns for children. Phthalate substitute, DINCH, shows a non-significant increasing pattern. For OPFRs, no trends were statistically significant. For women, BPA shows a clear decreasing pattern, while substitutes BPF and BPS show an increasing pattern coinciding with the BPA restrictions introduced. No clear patterns are observed for PAHs or cadmium. Although the causal relations were not studied as such, exposure levels to chemicals restricted at EU level visually decreased, while the levels for some of their substitutes increased. The results support policy efficacy monitoring and the policy-supportive role played by HBM. [ABSTRACT FROM AUTHOR]

Insect pest is a very common problem in tea garden where they caused a huge loss in each year. The study was conducted to measure the potentiality of a solar based LED light trap as an eco-friendly pest management technology in the tea garden of Bangladesh. The results showed that the highest number of insects from Coleoptera (3526) and Hemiptera (557) orders were captured under the solar based LED light trap while it was lowest in Hymenoptera (47) and Orthoptera (3). The study results also indicated that in an average of 9 days, total captured insects (number) were 725, 244, 146, 112, and 85 at 6-7, 7-8, 8-9, 9-10, and 10-11 pm, respectively while it was 656, 1004, 566, 3970, 602, 489, 680, 620 and 3222 at 1st to 9th days, respectively. Hence, the average decreasing rate with time (hourly) was computed at 66.34, 40.16, 23.29, and 24.11% compared to the 1st hour (6-7 pm). The average captured pattern of the insects compared to the 1st days was decreased or vice-versa. From 6.00 pm to 11.00 am, the initial light intensity was measured at 28 lux which raised up to 245 lux at 8.00 pm after that it down drastically. Light intensity has a positive relation with insect capture. Most of the Coleopteran and Hemipteran insects were captured under low light intensity in the early evening (6.00 pm). Therefore, the study suggested that the solar based LED light trap might have the potential to reduce a great number of tea pests in the tea garden.

The purpose of this study is to present and apply an innovative technique to model environmental consequences of shipping accidents in relations to events initiating those accidents. The Monte Carlo simulation technique is used to model shipping accidents and chemical release consequences within the world's sea and ocean waters. The model was created based on the previously designed novel general probabilistic approach to critical infrastructure accident consequences, including three models: the process of initiating events generated by a critical infrastructure accident, the process of environmental threats coming from released chemicals that are a result of initiating events, and the process of environmental degradation stemming from environmental threats. It is a new approach that has never been proposed and applied before. The Monte Carlo simulation method is used under the assumption of the semi-Markov model of these three processes. A procedure for the realization and generation of this process and evaluation of its characteristics is proposed and applied in the preparation of the C# program. Using this program, the processes' characteristics are predicted for a specific sea area. Namely, for the considered processes, the limit values of transient probabilities between the states and the mean values of total sojourn times at the particular states for the fixed time are determined. The results obtained can be used practically by maritime practitioners involved in making decisions related to the safety of maritime transport and to mitigation actions concerned with maritime accidents. [ABSTRACT FROM AUTHOR]

In the carbon capture and storage (CCS) infrastructure, the risk of a high-pressure buried pipeline rupture possibly leads to catastrophic accidents due to the release of tremendous amounts of carbon dioxide (CO2). Therefore, it is crucial to conduct an in-depth study on CO2 atmospheric dispersion when developing CO2 pipeline. In fact, the CO2 captured from diverse industrial processes may contain a variety of impurities. The combined effect of the toxicities of the multiple impurities increases the risk, which has usually been ignored by previous studies. In this paper, computational fluid dynamics (CFD) technology is applied to investigate the influence of hazardous chemicals on CO2 stream dispersion under different meteorological, complex terrain features, and ground temperature condition. In addition, the effect of combined toxic impurities on consequence distance was also investigated comprehensively. It was found that complex conditions affected the near-surface flow field, and obstacles enhanced the lateral dispersion of CO2. Compared to 288 K ground temperature, the plume area inside the 50,000 ppmv CO2 boundary decreased by 8.2%. The hazardous effects of combined toxic impurities became significant compared to a single toxic impurity. This study may furnish a viable assessment technique for the risks associated with CCS. [ABSTRACT FROM AUTHOR]

Taking the chemistry laboratories in universities as an example, the potential safety hazards that might arise during the storage and use of hazardous chemicals were pointed out. Based on the existing laboratory safety management system, a management method for joint prevention of hazardous chemicals by cooperation between police and schools was proposed. The operation of the joint prevention was explored, and the role of the use of information management platforms in the management of hazardous chemicals was also discussed. [ABSTRACT FROM AUTHOR]

International oil and gas corporations operating in Brunei may apply process safety management (PSM) and analysis techniques, resulting in varying approaches and measures to address process safety issues. Global corporations may have developed their own process safety standards while smaller firms employ established ones. This research compares the local PSM systems and standards with international ones to determine which employers face the most difficulties in implementing or increasing process safety inside their organizations. This study found that Occupational Safety and Health Administration (OSHA) regulations are used by 30% of local users in downstream operations. Common challenges encountered by local users are management/leadership commitment to process safety (11.9%), mechanical integrity and management of safety critical devices (5.3%), management review and intervention for continuous improvement (4.9%), communication amongst workers (3.8%), management of change (3.8%), operational control, permit to work and risk management (3.8%) and incident reporting (3.8%). [ABSTRACT FROM AUTHOR]

Human biomonitoring (HBM) data in Europe are often fragmented and collected in different EU countries and sampling periods. Exposure levels for children and adult women in Europe were evaluated over time. For the period 2000–2010, literature and aggregated data were collected in a harmonized way across studies. Between 2011–2012, biobanked samples from the DEMOCOPHES project were used. For 2014–2021, HBM data were generated within the HBM4EU Aligned Studies. Time patterns on internal exposure were evaluated visually and statistically using the 50th and 90th percentiles (P50/P90) for phthalates/DINCH and organophosphorus flame retardants (OPFRs) in children (5–12 years), and cadmium, bisphenols and polycyclic aromatic hydrocarbons (PAHs) in women (24–52 years). Restricted phthalate metabolites show decreasing patterns for children. Phthalate substitute, DINCH, shows a non-significant increasing pattern. For OPFRs, no trends were statistically significant. For women, BPA shows a clear decreasing pattern, while substitutes BPF and BPS show an increasing pattern coinciding with the BPA restrictions introduced. No clear patterns are observed for PAHs or cadmium. Although the causal relations were not studied as such, exposure levels to chemicals restricted at EU level visually decreased, while the levels for some of their substitutes increased. The results support policy efficacy monitoring and the policy-supportive role played by HBM.

The study is related to the improvement of the safety methodology for the application of dangerous chemical substances and the development of binding action and response algorithms for officials of the State Fire and Rescue Service, who first arrive at the sites of the event with the presence of dangerous chemical, biological, radioactive and explosive substances. The safety methodology is intended to quickly provide the primary information needed to the rescue team in the context of action at the site, which will allow for the possible negative effects and risks to the environment to be minimised as soon as possible and more effectively. The examination of the regulatory enactments determining the responsibility of the services and the regulatory documents governing action revealed the limits of the cooperation and responsibility of the services, as well as the division of functions in response to events with the hazardous substances as well as the assessment of the internal regulatory enactments of the services involved in cooperation, allowing for a better assessment of their resources and capacity in the event of an emergency. Also, the manuals, instructions and action algorithms of the European services were evaluated, which were taken into account, tested and used in cooperation between different services in the event of an emergency with dangerous substances. Based on the results of the study, an instruction was developed which included primary information necessary for the head of rescue works, in the context of action at the site, which would allow for the earliest and more efficient reduction of the potential adverse effects and risks to the environment caused by the event. The instruction will be included in the training course programme for the preparedness of fire rescuers and future rescue managers, which will significantly facilitate not only the implementation of the work process but also improve the quality of the training process of the College of Fire Safety and Civil Protection according to modern competencies.

The South Korean government currently designates toluene as a hazardous chemical, only limiting its use in products that are feared to be harmful. Since no measures to prohibit the use of toluene have been implemented, toluene is frequently detected in amounts that exceed the limit. Accordingly, the Government is considering implementing a plan to tighten the current regulations related to the use of toluene to prevent the occurrence of diseases caused by exposure and addiction to it. Therefore, the most important objective of this research is to evaluate quantitatively the economic benefits arising from the implementation of the plan in South Korea. To achieve the purpose of this paper, contingent valuation, an economic technique for analyzing data collected from a survey of people based on economic theory, is applied. For this purpose, a survey of 1000 people nationwide is conducted, and an analysis model that is well received in the literature is adopted. In other words, the annual willingness to pay (WTP) per household to strengthen the regulations to reduce the human health risks of toluene is evaluated to calculate its economic benefits. All the estimated WTP models secure statistical significance. The average WTP per household per annum is derived as KRW 3394 (USD 3.02). Considering that the country contained 20,573,060 households in 2021, the national economic benefits are calculated as KRW 69.82 billion (USD 62.23 million) every year. It is difficult to estimate accurately the costs incurred by tightening the regulations on toluene use, but they do not seem to exceed the benefits. Because tightening the regulations would be socially desirable, the Government would be justified in making this decision. [ABSTRACT FROM AUTHOR]

The purpose of this study is to present and apply an innovative technique to model environmental consequences of shipping accidents in relations to events initiating those accidents. The Monte Carlo simulation technique is used to model shipping accidents and chemical release consequences within the world’s sea and ocean waters. The model was created based on the previously designed novel general probabilistic approach to critical infrastructure accident consequences, including three models: the process of initiating events generated by a critical infrastructure accident, the process of environmental threats coming from released chemicals that are a result of initiating events, and the process of environmental degradation stemming from environmental threats. It is a new approach that has never been proposed and applied before. The Monte Carlo simulation method is used under the assumption of the semi-Markov model of these three processes. A procedure for the realization and generation of this process and evaluation of its characteristics is proposed and applied in the preparation of the C# program. Using this program, the processes’ characteristics are predicted for a specific sea area. Namely, for the considered processes, the limit values of transient probabilities between the states and the mean values of total sojourn times at the particular states for the fixed time are determined. The results obtained can be used practically by maritime practitioners involved in making decisions related to the safety of maritime transport and to mitigation actions concerned with maritime accidents.

Forestry pest management includes biological and chemical methods of pest control. Using insecticides and natural enemies can be compatible in forest pest management programs. The compatibility of the predatory stink bug Podisus distinctus with the insecticide indoxacarb, used in forestry, needs to be evaluated in Brazil. This study investigated the mortality, survival, respiration, preference, prey consumption, and locomotor activity of P. distinctus adults exposed to indoxacarb. In concentration-mortality bioassays, the lethality of indoxacarb (LC50 = 2.62 g L−1 and LC90 = 6.11 g L−1) was confirmed in P. distinctus adults. The survival rate was 100% in predator insects not exposed to indoxacarb, declining to 40.7% in predator insects exposed to 2.62 g L−1 and 0.1% in predators treated with 6.11 g L−1. Indoxacarb reduced the respiration of P. distinctus from 18.45 to 14.41 µL CO2 h−1 at 2.62 g L−1 for up to 3 h after insecticide exposure, inhibiting food consumption and displaying hyperexcitation. The harmful effects of indoxacarb to the natural enemy suggest that it should be better assessed for use with P. distinctus for pest management in forestry. [ABSTRACT FROM AUTHOR]

With the progress in science and technology, hazardous chemicals are becoming more essential in chemical products, industrial and agricultural production, and daily life. Hazardous chemicals have poisoning, corrosive, explosive, and combusting natures; once on fire, they can trigger a chain of catastrophic incidences, resulting in casualties, property loss, and environmental pollution and posing hazards to life and property. Using the "8-12" explosion of the Ruihai Logistics warehouse in Tianjin Port (Binhai New District, China), the present study analyzes the characteristics of trauma of the casualties in this accident and the emergency medical rescue strategies. The goals were to improve the ability of emergency rescue in such accidents and to save people's lives and property to the maximum extent. [ABSTRACT FROM AUTHOR]

The problem of infertile marriages has worsened recently in the world. Today there are 60.0 to 80.0 million infertile couples, in 40.0% of cases married couples are infertile due to a man's fault. The aim of the work is to analyze specialized scientific literature for generalization of data on modern views on etiology and pathogenesis of male infertility in urbanization. Materials and methods. Available scientific sources over the past five years, devoted to the mechanisms of male infertility in urbanization are studied by the methods of overview, system and content analysis. The data of the world statistics are presented and the data of modern researches devoted to the influence of chemical, physical and emotional factors on the parameters of male infertility are analyzed. It is accentuated on active forms of oxygen and parameters that reflect the morphological and functional state of spermatozoa, as well as the problems of male infertility that need to be addressed. A number of other factors affecting male infertility have been analyzed, in particular: food factors in urbanization, the role of chemical compounds in the anthropogenic environment, the importance of emotional factors and the risk caused by physical factors. Conclusions. It has been confirmed that external conditions have a serious impact on the development of reproductive system disorders in men, although their causes and structure are still unclear, are controversial despite a convincing list of factors that interfere with spermatogenesis. Based on the sources studied, it can be argued that there is no single model of oppression of the male reproductive function that can explain pathogenetic changes in various components of the reproductive apparatus, depending on the direction and strength of the adverse factor. The creation of such a model will make it possible to approach the issue of prevention of reproductive disorders in a context of various external factors. To study the relationship between stress and the development of secondary infertility and subfertility in men, it is necessary to study further the patterns obtained on the basis of clinical-laboratory, statistical and epidemiological studies.

The scope of this study is to protect the environment from the waste of Cr(VI) electroplating bath and convert it to the useful product. As known, Cr(VI) is a toxic materials and harmful for the health of workers and environment. Therefore, this study has aimed to develop the conversion process of the waste Cr(VI) electroplating bath to Cr(III). To identify the significant factors affecting the quality of Cr coating during the conversion, experimental design methodologies were applied. A full factorial experimental design was performed to specify the effects and interactions of the main factors and optimize the conversion process. The results were analysed statistically. The surface response method was carried out to determine the stability of the Cr(III) bath after the conversion. The maximum brightness was observed when the amount of sodium sulphate was 80–90 g/L and boric acid 60–65 g/L at pH 3.25. Coating defects were investigated using a scanning electron microscope (SEM). EDS measurements were taken to analyse the composition of the Cr coating. SEM images and EDS measurements indicated that the blackness and matte defects are due to the formation of sulphur in the Cr coating. [ABSTRACT FROM AUTHOR]

This paper presents evaluation of safety performance of three hazardous facilities based on current safety practice by measuring their safety weighted hazard indices (SWeHI) of multifarious units of chemical process and what can be done to avoid any potential accidents in context of Bangladesh. Assessing hazard potential over safety procuration is a key indicator of how well a facility is prepared to reduce its vulnerability. The risks associated with hazardous facilities are always greater in a country like Bangladesh as the safety issues are not often been prioritized by its key stakeholders. In recent years, there were number of deadly accidents occurred in the chemical industries and storage warehouses which resulted multiple fatalities and significant property damage. The accident could be avoided using proper safety protocols in those facilities. Here safety performance of three facilities was assessed based on survey data. These facilities deal with flammable, explosive and toxic chemicals. This index is on the basis of fire & explosions properties and toxic release properties as well as the safety precautions against it. It helps professionals to identify the overall hazard potential and distinguish less protected units from other well operated units. The paper features on an approximate yet workable assessment of risks at a low cost and based on the current safety practices. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The logistical problems that companies must face tend to have conflicting interests between customers and service providers, which makes them difficult to solve. In turn, when the activities involve the transport of hazardous materials, the problem becomes critical in security terms, and makes logistics operations even more difficult. In the hazardous materials transportation literature, problems related to the routing of vehicles and the geographic location of supply or service centres are often addressed. However, there are not many studies related to the study of the loading, unloading and weighing operations of trucks that handle hazardous materials within industrial plants. That is why this work presents a case study of the installation of a new truck balance in an industrial plant in Argentina. To do this, the internal logistics operation and the current state of the plant's infrastructure are analyzed. A detailed study of the alternatives for the location of the balance was carried out following the criteria set by the company's management and the problem was solved using an empirical weighting method coordinated with the heads of the Supply Chain Department. A satisfactory solution was obtained.

The primary attention in considering the fact that the percentage of hazardous chemicals consumption is inversely proportionate to the quality of ecological potential as one of the basic principles of rural development, which has direct implications for the development of agritourism, the research into the consumption of hazardous chemicals covering the period from 2011 to 2015 in the Republic of Serbia in comparison to EU 28 was conducted. The research was focused on the consumption of hazardous chemicals by divisions of Classification of activities, the consumption of hazardous chemicals by toxicity classes (A-E), and the analysis of the hazardous chemicals consumption by regions in the Republic of Serbia. The results obtained reveal the consumption of all hazardous chemicals classes per capita in Serbia is significantly lower than in the EU, and that the share of the most toxic classes is lower. Additionally, the trend of hazardous chemicals consumption is decreasing in Serbia, and stagnates in the EU. Particularly low consumption is registered in Southern and Eastern region as well as Sumadia and Western region, pointing out at the potential of these regions for development of agritourism based on this fact.

To make the biggest advantage of information system on dynamical monitoring of hazardous chemical enterprises, a work safety supervision platform with major hazard installation as the key monitoring objects is developed in Shandong province. The functions of platform cover work safety supervision, dynamical monitoring of major hazard installation, accident consequence analysis, decision-making for emergency plan. The successful construction and effective operation of the platform can help the emergency management agency not only reach the transformation of work safety supervision from static management to dynamic management, but also realize emergency rescue from subjective judgement to scientific decision. [ABSTRACT FROM AUTHOR]

Hazardous chemical is a kind of key hazard sources in universities, which is also a main factor for the accidents in the laboratories. At present the safety use of hazardous chemicals is a difficult target in universities due to the lack of safety education, physical protection facilities and supervisory team, lag of the safety management system and rewards and punishment system. In our university “3 + X’’ mode of campus safety education was carried out, and laboratory safety supervisory teams were constructed in college and university levels respectively, protection facilities were established and updated, and safety inspections for hazardous chemicals were strengthened. Moreover the information management system of hazardous chemical, and reward and punishment system on the safety management were constructed recently. With the series of measures the safety awareness of the technicians and students was increased, hence safety management level was improved. All of these measures are obviously beneficial to the safety and stabilization of campus. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Social Science) / Dongbei Daxue Xuebao (Shehui Kexue Ban) is the property of Dongbei Daxue and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Hazardous chemical explosion accidents are analyzed according to a hybrid approach. • Fault tree model is constructed using the association rule approach. • The influence of subjective factors in Bayesian network analysis is reduced by the accident data. • The process design and operation events have the greatest impact on the occurrence of accident. • Improper temperature control is the most likely to provoke accident directly. Hazardous chemical accidents pose a severe threat to human and economic activities. To explore the causes and paths of hazardous chemical explosion accidents (HCEAs) in China, a qualitative and quantitative model was proposed in this study. Firstly, 129 accident cases were collected from the official website of the Ministry of Emergency Management of the People's Republic of China, and the accident factors were screened based on association rule (AR). Then, the fault tree (FT) structure of HCEA was developed by the AR, and the qualitative model was transformed into a quantitative Bayesian network (BN) model. Finally, the accident path, the importance size of the basic events, and the sensitivity of the direct cause of the accident were uncovered based on the BN model. The results show that improper temperature control due to operating procedures is the most likely route to accidents. Among the basic events, process management and operating procedures issues ranked the first in importance, with the most significant impact on HCEA. The sensitivity of improper temperature control far exceeds other direct causes and is most likely to induce accidents directly. According to the study results, some feasible measures are put forward to improve the safety management of hazardous chemical production. [ABSTRACT FROM AUTHOR]

It is proposed that wastewater treatment facilities meet legislated discharge limits for a range of micropollutants. However, the heterogeneity of these micropollutants in wastewaters make removal difficult to predict since their chemistry is so diverse. In this study, a range of organic and inorganic micropollutants known to be preferentially removed via different mechanisms were selected to challenge the activated sludge process (ASP) and determine its potential to achieve simultaneous micropollutant removal. At a fixed hydraulic retention time (HRT) of 8 h, the influence of an increase in solids retention time (SRT) on removal was evaluated. Maximum achievable micropollutant removal was recorded for all chemicals (estrogens, nonylphenolics and metals) at the highest SRT studied (27 days). Also, optimisation of HRT by extension to 24 h further augmented organic biodegradation. Most notable was the enhancement in removal of the considerably recalcitrant synthetic estrogen 17α-ethinylestradiol which increased to 65 ± 19%. Regression analysis indicates that this enhanced micropollutant behaviour is ostensibly related to the concomitant reduction in food: microorganism ratio. Interestingly, extended HRT also initiated nonylphenol biodegradation which has not been consistently observed previously in real wastewaters. However, extending HRT increased the solubilisation of particulate bound metals, increasing effluent aqueous metals concentrations (i.e., 0.45 µm filtered) by >100%. This is significant as only the aqueous metal phase is to be considered for environmental compliance. Consequently, identification of an optimum process condition for generic micropollutant removal is expected to favour a more integrated approach where upstream process unit optimisation (i.e., primary sedimentation) is demanded to reduce loading of the particle bound metal phase onto the ASP, thereby enabling longer HRT in the ASP to be considered for optimum removal of organic micropollutants. [ABSTRACT FROM AUTHOR]

According to the data from authoritative sources, 1,400 sudden leakage accidents occurred in China during 2006 to 2011 were investigated, in which, 666 accidents were used for statistical characteristic abstracted with no or little damage. The research results were as follows: (1) Time fluctuation: the yearly number of sudden leakage accidents is shown to be decreasing from 2006 to 2010, and a slightly increase in 2011. Sudden leakage accidents occur mainly in summer, and more than half of the accidents occur from May to September. (2) Regional distribution: the accidents are highly concentrated in the coastal area, in which accidents result from small and medium-sized enterprises more easily than that of the larger ones. (3) Pollutants: hazardous chemicals are up to 95 % of sudden leakage accidents. (4) Steps: transportation represents almost half of the accidents, followed by production, usage, storage, and discard. (5) Pollution and casualties: it is easy to cause environmental pollution and casualties. (6) Causes: more than half of the cases were caused by human factor, followed by management reason, and equipment failure. However, sudden chemical leakage may also be caused by high temperature, rain, wet road, and terrain. (7) The results of principal component analysis: five factors are extracted by the principal component analysis, including pollution, casualties, regional distribution, steps, and month. According to the analysis of the accident, the characteristics, causes, and damages of the sudden leakage accident will be investigated. Therefore, advices for prevention and rescue should be acquired. [ABSTRACT FROM AUTHOR]

To investigate the occurrence and development pattern of large-scale hazardous chemicals emergencies, a statistical analysis of 195 large and above accidents of hazardous chemicals in China during 2000-2020 was conducted. A general description of the characteristics of larger and above accidents based on statistical data was analyzed, and then the system risk of the hazardous chemical industry was calculated and evaluated by the entropy weight method and the TOPSIS method comprehensively. Results show that: (1) The geographical distribution of large and above hazardous chemical accidents (LAHCA) varies significantly; (2) The high-temperature season has high probabilities of having large and above accidents; (3) Human factors and management factors are the main causes of LAHCA; (4) During the period from 2000 to 2020, due to the rapid development of the chemical industry, the overall risk of accidents involving hazardous chemicals were upswing accompanied by volatility, and the risk of serious accidents remains high. The development history of safety regulations in China's hazardous chemical sector and the industry's projected course for future growth were then discussed. Finally, based on the findings of the aforementioned statistics and research, specific recommendations were provided for the safety management of the hazardous chemical sector. This study expects to provide a practical and effective reference for the construction of safety management as well as accident prevention in the hazardous chemical industry.