Unintentional Persistent Organic Pollutants Research Articles

Insight into the inhibition mechanisms of Ca-, N-, S-containing compounds on persistent organic pollutant formation from the thermal reaction of anthracene on copper chloride

Four inhibitors (CaO, CaS, CH4N2S, and (NH4)2SO4) were employed to inhibit the formation of multiple unintentional persistent organic pollutants (POPs) and environmentally persistent free radicals (EPFRs) using anthracene as a precursor, with CuCl2 serving as both a transition metal catalyst and chlorine source. The inhibition mechanisms were elucidated in terms of chlorine immobilization, catalyst deactivation, and free radical regulation. The inhibition efficiency of the four inhibitors on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs) ranged from 64.7 % to 98.4 %, with the corresponding inhibition rates on toxic equivalency quantity ranging from 86.3 % to 99.7 %. The distribution of homologs shifted towards less chlorinated species, indicating effective suppression of chlorination. Calcium- and nitrogen-containing compounds consumed chlorine sources by forming CaCl2, CaClOH, and NH4Cl, while sulfur-containing compounds deactivated catalysts by forming CuSO4. EPFRs derived from anthracene were identified as carbon-centered anthracene-type and anthraquinone-type radicals. Positive correlations were observed between POPs and EPFRs concentrations, suggesting the pivotal role of organic free radicals as intermediates in POPs formation. Anthraquinones derived from anthracene underwent decomposition, recombination and chlorination, leading to the formation of PCDD/Fs and PCBs. The addition of inhibitors reduced EPFRs concentrations by 74.2–95.1 %. Sulfur- and nitrogen-containing inhibitors generated radicals that attacked POPs precursors and intermediates, forming heteroatomic compounds and inhibiting POPs formation. These findings enhanced the understanding of the source control mechanisms of POPs and provided theoretical and technical support for the synergistic inhibition of POPs and EPFRs in industrial thermal processes.

Đánh giá mức độ phát thải của các chất polyclodibenzo-p-dioxin và polyclodibenzofuran phát sinh không chủ định từ lò đốt rác chất thải sinh hoạt và rác thải công nghiệp ở Việt Nam

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) are the most toxic substances among the group of unintentional persistent organic pollutants (U - POP) generated from many sources, in which domestic and industrial waste incinerators are the highest emission risk. Assessment of pollution potential and dioxin/furan emissions from incinerators in developing countries, including Vietnam, is still limited; especially in-depth studies on the content and characteristics of PCDD/PCDF emitted into the atmosphere. Therefore, the research team evaluated the emission potential and characteristics of 07 PCDD and 10 PCDF, those are considered to be the most toxic isomers and congeners, from stack gas samples collected from incinerators at 33 facilities in 11 provinces in Vietnam. The total concentration of PCDD/PCDF in the industrial incinerators’ emission ranged from 37.3 to 3348.6 pg TEQs/m3 and domestic waste incinerators had lower total concentrations and fluctuated within about 37.3-1323.8 pg TEQs/m3. The characteristic of incinerator emissions is that the proportion of 2,3,7,8- TCDD accounts for 2.9 to 9.04%. The highest contributing concentrations were congeners 1,2,3,7,8-PeCDD, with its contributing percentage from 22.95-32.42%. The second largest contributor is congeners 2,3,4,7,8- PeCDF, accounting for 20.94- 21.50% of the total toxic congeners of PCDD/PCDF in both types of incinerators. However, in terms of toxic equivalency (TEQ), the concentration of industrial waste incinerators is much higher than that of domestic waste incinerators. The results of stack gas samples showed that the PCDD/PCDF content for domestic waste incinerators has 5/17 establishments that exceeded the permissible standard threshold: 0.6 ng/Nm3, according to QCVN 61-MT:2016/BTNMT. Industrial waste incinerators have 5/16 establishments that exceeded the permissible standard threshold: 0.6ng/Nm3 for furnaces with a capacity of 300kg/hour according to QCVN 30:2012/BTNMT.

Unintentional persistent organic pollutants in cremation process: Emissions, characteristics, and inventory

Pollutants produced by cremation furnaces have gradually caused concern because of the increasing rate of cremation around the world. In this study, the levels, patterns, and emission factors of unintentional persistent organic pollutants (UPOPs) from cremation were investigated. The toxic equivalent (TEQ) concentrations (11 % O2 normalized) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in flue gas ranged from 0.036 to 22 ng TEQ/Nm3, while the levels of polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) in flue gas samples ranged from 0.0023 to 1.2 ng TEQ/Nm3 and 0.17–44 pg TEQ/Nm3, respectively. The average concentrations of UPOPs in flue gas from car-type furnaces were higher than those from flat-panel furnaces. Secondary chambers and air pollution control devices were effective for controlling UPOPs emissions. However, heat exchangers were not as effective for reducing UPOPs emissions. It was observed that the UPOPs profiles exhibited dissimilarities between fly ash and flue gas samples. HxCDF, OCDD, and PeCDF were the dominant homologs of PCDD/Fs in flue gas, while HxCDF, PeCDF, and HpCDF were the dominant homologs in fly ash. The fractions of MoCBs and MoCNs in fly ash were higher than those in flue gas. Finally, we conducted an assessment of the global emissions of UPOPs from cremation in the years of 2019 and 2021. The total emission of UPOPs in 47 countries was estimated at 239 g TEQ in 2021, which was during the peak period of the COVID-19 pandemic worldwide. The emissions in 2021 increased by approximately 24 % compared to 2019, with the impact of COVID-19 being a significant factor that cannot be disregarded.

Biological wastewater treatment plants as sources of environmental pollution by persistent organic pollutants (on the example of Odesa industrial-and-urban agglomeration)

Formulation of the problem. Effective mechanism of wastewater treatment (WT) are important components of reducing anthropogenic load on the environment. One of the most widespread mechanisms of urban wastewater treatment is the biological treatment on a Biological Wastewater Treatment Plant (BWTP). However, increasing the nomenclature of pollutants concentrated in urban wastewater seriously affects the effectiveness of WT on BWTPs, which are not intended for such a wide spectrum of specific pollutants such as, in particular, Persistent Organic Pollutants (POPs). The control of their intake into the environment must be regulated according to the Stockholm convention. The goal of the research is the evaluation of the intake of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) into the environment from the wastewater of Odesa Industrial-and-Urban Agglomeration (IUA) and determining the volumes of their accumulation in the sea environment. Purpose. The assessment of the amount of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) entering the environment with the wastewater from Odesa IUA and determining the amount of their accumulation in the sea environment. Methods. In our research, all available official methods of calculation of the unintentional formation of POPs were reviewed, as a result – the main and most complete methods were selected: «UNEP (2013). Toolkit for Identification and Quantification of Releases of Dioxins, Furans and Other Unintentional POPs» and «EMEP/EEA air pollutant emission inventory guidebook. Technical guidance to prepare national emission inventories, 2019». For evaluation of PCDD/F accumulation in the sea environment an improved by authors methodology for calculation of PCDD/F accumulation with their cumulative effect and half life taken into account was used. Results. The work provides justification for the necessity of use of calculation methodologies for determing the intake of PCDD/F to the sea environment adjacent to Odesa IUA; annual massed of PCDD/F entering the sea environment as part of treated, insufficiently treated and untreated wastewater are calculated; massed of PCDD/F that accumulate in waste activated sludge (WAS) on BWTP are calculated; volumes and specifics of PCDD/F accumulation in the sea basin, where the wastewater of Odesa IUA is being discharged to are determined using the improved methodology that enables taking into account the cumulative effect and half life period of these substances; mass and concentration of PCDD/F, immobilized in WAS, are determined, the excess level of concentration of PCDD/F in WAS compared to the maximum permissible concentration is determined. The total accumulation of PCDD/F in the sea environment over 2007-2017 period is determined. Conclusions. It was established that the use of calculation methodologies for evaluating PCDD/F volumes in the water environment is the only and necessary condition for satisfying the requirements of the Stockholm convention due to the impossibility of performing a regular instrumental monitoring of PCDD/F intake into the water environment. The use of suggested by us improved methodology for calculation of PCDD/F accumulation with their cumulative effect and half-life period taken into account allows for calculation of PCDD/F masses that were formed throughout the year under consideration, taking into account the PCDD/F masses that were formed during previous years as well.

Exploring N/S-Based Polymers for Synergistic Inhibition of Multiple Unintentional Persistent Organic Pollutants during Iron Ore Sintering

Exploring N/S-Based Polymers for Synergistic Inhibition of Multiple Unintentional Persistent Organic Pollutants during Iron Ore Sintering

Concentrations, congener patterns, and correlations of unintentional persistent organic pollutants in cement kilns co-processing hazardous waste

Emissions from two typical cement kilns co-processing different kind of hazardous waste were analyzed for 143 congeners of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls, polychlorinated naphthalenes, polybrominated dibenzo-p-dioxins and dibenzofurans, and polybrominated diphenyl ethers. The congener distributions in different process stages were investigated. One of the plants co-processed waste chemical reagents from laboratories. The emission factor (TEQ basis) for the plant was 2.09 ng WHO2005 TEQ/t, with the kiln head and the kiln back end contributing 1.18, 0.91 ng WHO2005 TEQ/t, respectively. The other plant co-processed municipal waste incineration fly ash. The emission factor for the plant was 0.12 ng WHO2005 TEQ/t, with the kiln head and the kiln back end contributing 0.022, and 0.10 ng WHO2005 TEQ/t. These results indicate that co-processing of waste containing reagents from laboratories may lead to higher emission levels than co-processing of other types of waste. The congener patterns of persistent organic pollutants (POPs) in ash samples from the humidifier tower were similar to those in samples from the bag filter at the kiln back end. The correlation coefficients of five pollutants between the humidifier and bag filters samples were generally high, which indicated that conditions in those two stages similarly favored the formation of these POPs. Comparison of the concentrations for different process stages suggested that the main stage for formation of unintentional POPs was the humidifier tower. These results improve our understanding of emission characteristics and could be used for simultaneous control of multiple POPs.

Synergetic promoting/inhibiting mechanisms of copper/calcium compounds in the formation of persistent organic pollutants and environmentally persistent free radicals from anthracene

Copper compounds are considered the strongest promotors of unintentional persistent organic pollutants (POPs) formation, while calcium compounds are widely used to inhibit this process. Understanding the mechanisms underlying these processes is important for synergetic control of multiple POPs. Herein, the promoting ability of CuCl2 on the synergetic formation of POPs from anthracene and the underlying mechanisms were clarified. During thermochemical reaction with CuCl2, Cu2+ was first reduced to Cu+, and finally oxidized to CuO. Furthermore, CuCl2 promoted the formation of environmentally persistent free radicals (EPFRs) during thermochemical reaction. The formed EPFRs were identified as anthrone-type and anthraquinone-type radicals using electron paramagnetic resonance spectroscopy and gas chromatography/quadrupole time-of-flight mass spectrometry. Synergetic inhibition of POPs and EPFRs was achieved using CaO. The inhibiting mechanism of CaO was attributed to the absorption of chlorine originating from CuCl2 through the formation of CaClOH and the inhibition of free radical intermediates for POPs formation.

Concentrations, Congener Patterns, and Correlations of Unintentional Persistent Organic Pollutants in Cement Kilns Co-Processing Hazardous Waste

Concentrations, Congener Patterns, and Correlations of Unintentional Persistent Organic Pollutants in Cement Kilns Co-Processing Hazardous Waste

Formation of Environmentally Persistent Free Radicals during Thermochemical Processes and their Correlations with Unintentional Persistent Organic Pollutants.

Attention is increasingly being paid to environmentally persistent free radicals (EPFRs), which are organic pollutants with the activities of free radicals and stabilities of organic pollutants. EPFRs readily form during thermal processes through the decomposition of organic precursors such as phenols, halogenated phenols, and quinone-type molecules, which are also important precursors of toxic unintentionally produced persistent organic pollutants (UPOPs). We have found that EPFRs are important intermediates for UPOP formation during thermal-related processes. However, interest in EPFRs is currently mostly focused on the toxicities and formation mechanisms of EPFRs themselves. Little information is available on the important roles EPFRs play in toxic UPOP formation during thermal processes. Here, we review the mechanisms involved in EPFR formation and transformation into UPOPs during thermal processes. The review is focused on typical EPFRs, including cyclopentadiene, phenoxy, and semiquinone radicals. The reaction temperature, metal species present, and oxygen concentration strongly affect EPFR and UPOP formation during thermal-related processes. Gaps in current knowledge and future directions for research into EPFR and UPOP formation, transformation, and control are presented. Understanding the relationships between EPFRs and UPOPs will allow synergistic control strategies to be developed for thermal-related industrial sources of EPFRs and UPOPs.

Inventories and assessment of POPs in the State of Kuwait as a basis for Stockholm Convention implementation

Since 2006, Kuwait has been a party to the Stockholm Convention (SC) on Persistent Organic Pollutants (POPs). According to Article 7 of the SC, each party should develop a National Implementation Plan (NIP) and endeavour to implement the plan for the control and elimination of POPs. A first detailed National Implementation Plan has been developed for Kuwait with the support of the Stockholm Convention Regional Center for Capacity-Building and the Transfer of Technology for West Asia (SCRC Kuwait) in KISR. It includes a detailed action plan to manage and control the POPs in the country but also with activities to further give regional support for POPs monitoring and management. The current paper discusses the major inventory findings for the individual POPs groups including POPs pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers, and hexabromocyclododecane (HBCD) as well as Perfluorooctanesulfonic acid (PFOS) and unintentional POPs. Besides, information from POPs monitoring studies in Kuwait relevant to the NIP is shortly compiled for further informing on the current situation of POPs in Kuwait. Selected soil samples were collected and analyzed for selected POPs during the NIP development to generate supplementary information to the POP monitoring studies already conducted in Kuwait. Further relevant areas for the POPs management and control were assessed during the NIP development and are listed in the paper. One finding in the NIP assessment was that some of the alternatives used are also bioaccumulative with toxicity in biota and that in the NIP implementation. Also, alternative pesticides in the current use are an issue of concern. Therefore one activity in the implementation of the NIP is the avoidance of regrettable alternatives and the use of more sustainable and green chemicals.

Formation mechanism of unintentionally produced persistent organic pollutants in industrial thermal processes

Persistent organic pollutants (POPs) can be unintentionally produced and emitted in industrial thermal processes. The investigation of their formation mechanism is the basis for the development of source reduction technologies. In this paper, we found some new breakthroughs in the theory of dioxin formation on the basis of literature. The research on the formation of free radical intermediates from precursors such as chlorophenols and chlorobenzenes in thermal processes can reveal the formation mechanism of dioxin at the molecular level, which enriches the theoretical system of POPs formation. It is also found that the type and content of carbon sources, chlorine sources and catalytic metals are the key factors influencing the generation and emission of typical unintentional POPs in industrial thermal processes such as incineration and metallurgy. This paper also highlights the key role of transition metal chlorides in the generation of POPs, which can serve as not only a catalyst for the reaction, but also an inorganic chlorine source to chlorinate organic compounds with macromolecular carbon structures, thus promoting the formation of POPs. This review can provide important theoretical basis for the source control of POPs.

State of art control of dioxins/unintentional POPs in the secondary copper industry: A review to assist policy making with the implementation of the Stockholm Convention

Article 5 of the Stockholm Convention requires that each Party shall take measures to reduce the releases from anthropogenic sources of unintentional persistent organic pollutants (UPOPs), with the goal of their continuing minimization and, where feasible, their ultimate elimination. A major source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and other unintentional POPs releases, both in China and worldwide, is the metal industry in particular secondary metal industries such as copper smelting. More than 50% of the global secondary copper production is now in China and high levels of PCDD/Fs are released from these operations with the national inventory of China reporting a total of 1133.8 g toxic equivalents (TEQ) yr−1. Consequently the Global Environment Facility (GEF) is supporting the project ‘UPOPs Reduction through best available techniques and best environmental practices (BAT/BEP) in the secondary copper production sector’ in China compromising >50% of the global secondary copper production. As part of this project, information on relevant UPOPs from the metal industry have been reviewed and is presented here. This information should also be useful for other (developing) countries for controlling UPOPs releases from metal industries. This review and the information it contains provides a robust resource for policy makers, the industry and researchers to improve secondary copper production to BAT/BEP standards in relation to the reduction of PCDD/Fs and other UPOPs release. The contents include the details required to assist the understanding of the formation of chlorinated UPOPs along with their brominated and brominated-chlorinated analogues. It reviews the international sources of information on BAT/BEP, including the integrated approach considered in the European BAT Reference document, and shows how this can be used to achieve an overall reduction of pollutant releases from the industry. The current national standards of PCDD/F limits to air, water and solid residues have been compiled and are also included. Challenges which need to be addressed, such as the current international lack to consider brominated and mixed bromo-chloro PXDD/Fs which might be more environmentally significant than PCDD/Fs in some facilities – are also discussed.The study includes a brief description of the steps China has taken to change the national regulatory framework and to improve the sustainability of its secondary metal industry. The Stockholm Convention BAT/BEP guidelines recommend consideration of integrated pollution prevention and control and sustainable production as general principles which parties may incorporate when applying the BAT/BEP guidelines and guidance. This holistic approach is considered in the current project and in the improvement of the pilot facilities and will also be considered in the replication of experiences in other facilities. Using this approach ensures the implementation of the Stockholm Convention can contribute to integrated pollution prevention and control, the development of a circular economy and consequently to genuinely sustainable development thus contributing to different sustainable development goals (SDGs). It is hoped this approach will be adopted in other developing and transition economies and thus help to achieve improvements of the secondary metal industry globally.

Inventory of Polychlorinated Naphthalene Emissions from Waste Incineration and Metallurgical Sources in China.

Polychlorinated naphthalenes (PCNs) are highly toxic persistent organic pollutants (POPs) that are a relatively new addition to the Stockholm Convention as of 2015. The levels of unintentional emissions of PCNs from important industrial thermal sources on national scales are unclear but are important for understanding potential human exposure. In this study, an inventory was compiled of PCN emissions from priority industrial sources of unintentional POPs in China. Estimated emissions from four typical POP sources in the reference year (2014) in China were 511.6 kg by mass and 7650.8 mg of toxic equivalent. Waste incineration, secondary nonferrous smelting, electric arc furnace steelmaking, and iron ore sintering plants contributed 38.8, 15.4, 29.2, and 16.6%, respectively, to the total emissions. The Eastern Seaboard of China and the Hebei region in North China, which have intensive industrial activity and high population densities, were dominant contributors of PCNs. Only 18.6% of the counties where waste incineration plants were located emitted PCNs at a level higher than 1.00 × 10-1 mg of toxic equivalent, whereas 80% of the counties where metallurgical plants were located emitted PCNs at this level. These results indicate effective implementation of POP control in the waste incineration industry in China. This study clarifies the unintentionally emission levels of PCNs in China and provides important information for strategy development to control source emissions.

Efficacy of the novel continuous sampling system for PCDD/Fs and unintentional persistent organic pollutants.

Long-term sampling is essential for monitoring the air pollutants emitted from stack since it can monitor the pollutants emission continuously including the stages of start-up, shutdown and normal operation. However, commercial continuous sampling equipment such as AMESA faces the challenges of high weight and complicated sampling procedures. This study has developed a long-term and automatic sampling system (National Central University continuous stack sampling system, NCU-CS3), and compared the efficiency with manual sampling train (MST). The results indicate that relative standard deviation (RSD) of PCDD/Fs concentrations measured between NCU-CS3 and MST is <20%, demonstrating that the difference between NCU-CS3 and MST in measuring PCDD/Fs is insignificant. Besides, the effects of adsorbent temperature, adsorbent amount and type of adsorbent on breakthroughs of PAHs and unintentional-persistent organic pollutants (UPOPs) such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), chlorinated phenols (CPs), chlorinated benzenes (CBs) and polychlorinated naphthalenes (PCNs) are evaluated. The results indicate that the breakthrough of pollutants increases with increasing temperature of XAD-2 and decreases with increasing XAD-2 amount. Moreover, XAD-4 is used as alternative adsorbent to test the breakthrough and the results indicate that the breakthroughs of UPOPs of XAD-4 as adsorbent are lower than that with XAD-2 due to higher specific surface area of XAD-4. Furthermore, the residual of PCDD/Fs with NCU-CS3 as the sampling train is relatively low (1.5-3.8%), which meets the regulation of EN 1948-5 (10%).

Thermochemical formation of multiple unintentional persistent organic pollutants on metallurgical fly ash and their correlations

Metallurgical processes are currently the predominant anthropogenic sources of multiple unintentional persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs), chlorinated and brominated PAHs (Cl-PAHs and Br-PAHs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and polybrominated diphenyl ether (PBDEs). Understanding the formation of multiple POPs is important for source control. These POPs could be formed through fly ash-mediated heterogeneous reactions. In this study, we comprehensively investigated the thermochemical (150–450 °C) formation of these POPs on fly ash samples collected from a secondary aluminum smelter, secondary lead smelter, and iron ore sintering plant. The maximum concentrations of PCNs and PCBs were 154.5 and 181.3 times those in the original fly ash, respectively. Formation variations of PAHs, Cl-PAHs and Br-PAHs, and PBDEs were different from that of PCBs and PCNs. The PAHs concentration, which was the highest among the POPs in the original fly ash, decreased sharply by 95% at 150 °C. The ∑19Cl-PAHs and ∑19Br-PAHs increased marginally at 250 °C before decreasing slightly at 350 °C. The PBDE concentrations decreased under 250 °C and increased at 350 °C. PCNs, PCBs, and PCDD/Fs showed good correlations, all of which had a negative relationship with the PAHs. There were no significant correlations between PAHs and Cl/Br-PAHs. Low brominated congeners could be formed by destruction of higher brominated congeners because of thermal instability of the PBDEs.

Gas chromatography-Orbitrap mass spectrometry screening of organic chemicals in fly ash samples from industrial sources and implications for understanding the formation mechanisms of unintentional persistent organic pollutants

Clarifying the occurrences of organic chemicals in fly ash produced during industrial thermal processes is important for improving our understanding of the formation mechanisms of toxic pollutants such as polycyclic aromatic hydrocarbons (PAHs), halogenated PAHs, dioxins, and other unintentional persistent organic pollutants. We developed a highly sensitive gas chromatography-Orbitrap mass spectrometry (GC-Orbitrap/MS) method and applied it to screening of organic pollutants in fly ash samples from multiple industrial thermal processes. The GC-Orbitrap/MS method could detect and quantify organic pollutants at part per billion (ppb) levels. In total, 96 organic chemicals, including alkanes, benzene derivatives, phenols, polycyclic aromatic hydrocarbons, and biphenyl derivatives were identified in the fly ash samples. Several organic chemicals with chlorine or bromine substituents were abundant in secondary copper smelter fly ash, and these might act as precursors for formation of dioxins, brominated dioxins, and other dioxin-like compounds. Several chlorinated and brominated PAH compounds were also found in the secondary copper smelter fly ash. PAHs were dominant chemicals in the secondary aluminum smelter fly ash samples, and were present in much higher concentrations than in the samples from other industries. This indicates that there are different chemical formation pathways in different industries. Possible formation pathways of PAHs and dioxins were investigated and deduced in this study. These results improve our understanding of the formation mechanisms of toxic unintentional persistent organic pollutants and could be useful for reducing their source emissions.

ХАРАКТЕРИСТИКА НАСЛІДКІВ ВПЛИВУ ПОЖЕЖІ НА ЛЬВІВСЬКОМУ ПОЛІГОНІ ТВЕРДИХ ПОБУТОВИХ ВІДХОДІВ НА ДОВКІЛЛЯ

The old-fashioned system of municipal solid waste management (MSW) is one of the numerous environmental problems in Ukraine. Uncontrolled dumping of waste poses a serious threat to the environment due to the migration of landfill gases and leachates from the landfills. Moreover, as a consequence of collecting unsorted wastes enriched by organic materials and non-compliance with the rules of their storing, the emergence of fires has become more evident. One of the most important accidents is the fire that took place at the Lviv landfill located near the village of Velyki Hrybovychi in May 2016. The third by the scale dump in Europe that occupies more than 45 hectares of land, has caused the death of four people and formed a large-scale spreading of dangerous pollutants. The purpose of this study is assessing the magnitudes of damages caused by fire at Lviv landfill and identifying the nature of pollutants harmful to the environment and human health. The studies were based on the monitoring observation performed by the State Environmental Inspection of Lviv region concerning the status of atmospheric air, surface waters and soils within three months after the incident. The scale of persistent organic pollutants (POPs) emission, as well as the soil and surface water pollutions caused by lead, cadmium, copper, zinc, cobalt, chromium, manganese and iron compounds, have been analysed. The dynamics of water stream pollutions by ammonia nitrogen, nitrites, phosphates, chlorides and petroleum products were investigated. The content of oxygen dissolved in the waters of the Malekhіvka River was estimated by biological oxygen demand that describes the self-cleaning processes of surface water. There were observed significant concentrations of heavy metals belongs to the second degree of danger together with the abnormal spreading of ammonium salts, nitrites and petroleum products in the environment. These compounds were kept in nature at a high level for almost two months. The negative impact of the smog that covered the Lviv city and surrounded villages also was detected. A problem of particular concern is spreading of unintentional POPs prohibited by Stockholm convention on POPs that come in force in 2007 in Ukraine. The role of POPs in transboundary pollution was detected indirectly and requires additional research. The revealed changes in geosystem have inclined the quality of life in the nearest settlements and increased the level of pollution of the Poltava River that belongs to the Baltic Sea Catchment. It is evident that the negative impact of the Lviv landfill on the environment is a complex problem. In order to ensure the safety of the population and components of the environment, it is essential to carry out measures for recultivation of the landfill and its subsequent maintenance in accordance with sanitary requirements. Modification of the slopes of landfill body and its cover is a precondition for preventing landslides and self-ignition of waste. It also will make a precondition for reducing the amount of filtrate and the flow of dangerous water-soluble compounds from the landfill body to the environment.

Potential sources of unintentionally produced PCB, HCB, and PeCBz in China: A preliminary overview

Under the Stockholm Convention on Persistent Organic Pollutants (POPs), China is required not only to reduce polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) but also unintentionally produced polychlorinated biphenyls (PCB), hexachlorobenzene (HCB) and pentachlorobenzene (PeCBz). A baseline of the sources in China that generate these unintentional POPs is needed for both research and regulation purposes. In this paper, we have compiled production data of potential sources in China and assessed them in five-year intervals from 2000 to 2015. Most of these activities experienced changes from rapid growth to slow growth. Measured data for PCB, HCB and PeCBz in samples collected from potential sources in China were reviewed. Most information was associated to thermal processes with high potential of emission, including waste incineration and ferrous and non-ferrous metal production. In addition, high levels of PCB, HCB and PeCBz were found as impurities in a few chlorinated products or as by-products in solvent production, which suggested organochlorine industry might be important sources. Finally, based on the studies reviewed, recommendations for future actions in research and policy as well as a few regulatory issues in China are discussed.

Đánh giá hàm lượng dioxin/furan từ khí thải của một số loại hình công nghiệp và dân sinh ở Việt Nam

Dioxins and dioxin-like compounds (DLCs) are also classified by the Stockholm Convention as unintentional persistent organic pollutants (UPOPs). These toxic substances can be produced and released into the environment from many activities such as: incineration (domestic waste, industrial waste, medical waste, etc), metallurgy (steel processing, zinc recycling, aluminum production,...), manufacturing process and using organochlorine compounds (pesticides, bleach,...). The formation and emission of dioxin into the environment become more and more complex and difficult to control according to the industrial development. Therefore, the survey of dioxin emission into the environment from existing industrial and household waste treatment facilities is very necessary. On-the-spot sampling and dioxin analyzes carried out by Dioxin Analytical Laboratory and the Environmental Analysis Laboratory, the Environmental Chemistry Division, Vietnam-Russia Tropical Center. The report was built on the basis of data/information collection, analysis and assessment of dioxin emission from some types of industrial and households activities in Vietnam in the period 2012 -2017. This will be basis for assessing the concentrations of dioxin/ furan environmental pollution in order to better control environmental quality in Vietnam.

Estimating national dioxins and furans emissions, major sources, intake doses, and temporal trends in Iran from 1990\u20132010

BackgroundPolychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDFs) are highly toxic persistent organic pollutants (POPs), which can cause various health outcomes, such as cancer. As a part of the National and Sub-national Burden of Disease Study (NASBOD), we aimed to estimate dioxins and furans national emissions, identify their main sources, estimate daily intake doses, and assess their trend from 1990–2010 in Iran.MethodsThe Toolkit for Identification and Quantification of Releases of Dioxins, Furans and Other Unintentional POPs, which is developed by the United Nations Environment Programme (UNEP 2013), was used to estimate the emissions of PCDD/PCDFs from several sources into the air, water, land, residue, and other products. The daily intake doses were estimated using a linear regression of estimated emissions by UNEP Toolkit and average intake doses in other countries. Finally, the trend of PCDD/PCDFs emissions and daily intake doses were explored from 1990–2010.ResultsThe total emissions were estimated as 960 g Toxic Equivalents (g TEQ) for 1990 and 1957 g TEQ for 2010 (18.2 and 26.8 g TEQ per million capita, respectively). The estimations suggest that albeit contribution of open burning to PCDD/PCDFs emissions has been declining from 1990 to 2010, it remained the major source of emissions in Iran contributing to about 45.8% out of total emissions in 1990 to 35.7% in 2010. We further found that PCDD/PCDFs are mostly emitted into the ambient air, followed by residue, land, products, and water. The daily intake doses were estimated to be 3.1 and 5.4 pg TEQ/kg bw/day for 1990 and 2010, respectively. We estimated an increasing trend for PCDD/PCDFs emissions and intake doses in Iran from 1990–2010.ConclusionsThe high levels of emissions, intake doses, and their increasing trend in Iran may pose a substantial health risk to the Iranian population. Further studies with more rigorous methods are recommended but this should not circumvent taking appropriate policy actions against these pollutants. Currently, Iran has no standard for dioxins and furans. Adaptation of the World Health Organization recommended guidelines might be an appropriate starting point to control dioxins and furans emissions.