Feasibility of gas chromatography-atmospheric pressure photoionization-high-resolution mass spectrometry for the analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in environmental and feed samples.

In this work, the suitability of atmospheric pressure photoionization (APPI) has been assessed for the determination of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) by gas chromatography-high-resolution mass spectrometry (GC-HRMS). The APPI of target compounds has been tested in both positive and negative ion modes. Under positive ion mode, the analytes generated the molecular ion, which was favoured using dopants that promote charge exchange gas-phase reactions (i.e., benzene), while in negative ion mode, the ion [M-Cl+O]- for PCDFs and dl-PCBs were mainly formed, providing the best results using benzene and diethyl ether as dopants, respectively. Concerning PCDDs, highly chlorinated congeners were mainly ionized by means of the [M-Cl]- ion, whereas [M-Cl+O2]- was the base peak for tetraCDD and [M-Cl+O]- for penta- and hexaCDDs. Method quality parameters, in accordance with the current EU Regulation guidelines for food and feed analysis, showed the good performance of the two GC-APPI-HRMS (Orbitrap) methods since they provided high detection capability (low fg levels), good linearity, and satisfactory precision (RSD% < 9%). In addition, the GC-APPI-HRMS (Orbitrap) methods were validated by analysing selected environmental and feed samples and the results were compared to those obtained using conventional GC-EI-HRMS, demonstrating the good performance in the analysis of the target compounds. Hence, the GC-APPI-HRMS technique can be proposed as alternative to the conventional methods for the determination of PCDD/Fs and dl-PCBs in environmental and feed matrices.

Monitoring dioxins and furans in plasma of individuals living near a hazardous waste incinerator: Temporal trend after 20 years.

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in 40 plasma samples of individuals living in zones under potential influence of the emissions of a hazardous waste incinerator (HWI) (Tarragona County, Catalonia, Spain). Samples corresponded to subjects of different gender, age and specific areas of residence. The levels of PCDD/Fs were compared to those obtained in a baseline study (1998), as well as in previous surveys (2002, 2007 and 2012). The current mean concentration of PCDD/Fs in plasma was 6.79 pg I-TEQ/g lipid, which was significantly lower than the baseline concentration (27.0 pg I-TEQ/g lipid). A significant decrease was also observed in comparison to the results obtained in 2002 and 2007 (15.7 and 9.4 pg I-TEQ/g, respectively), while the current PCDD/F levels were similar to those obtained in 2012 (6.18 pg I-TEQ/g lipid). This important reduction in plasma PCDD/F levels is in accordance with the decreasing trend in the daily dietary intake of PCDD/Fs, which diminished from 210.1 pg I-TEQ (baseline) to 8.54 pg WHO-TEQ (current). OCDD was the predominant congener in plasma, while 2,3,7,8-TeCDD and 1,2,3,4,7,8,9-HpCDF showed the lowest levels. Based on the above results, as well as other recent data on the levels of PCDD/Fs in human milk, we conclude that the presence of the HWI does not mean additional and significant risks -as regards to PCDD/F exposure-for the population living in the neighborhood of the facility.

Fast extraction of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran in sewage sludge and soil samples.

The current environmental legislations recommend monitoring chemical contaminants such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans before the use of sewage sludge on the agricultural land. In this study, a solid-liquid extraction with low-temperature purification (SLE-LTP) was optimized and validated to determine 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran in sewage sludge and soil samples. The analyses were performed by gas chromatography-mass spectrometry operating in the selective ion mode (GC-MS-SIM). Acetonitrile:ethyl acetate 6.5:1.5 (v/v) was the best extraction phase, and the recoveries percentages were close to 100%. The linearity was demonstrated in the range of 1.25-25 µg L-1 of 1.25-20 µg L-1 for sewage sludge and soil, respectively. Matrix effect was proved for the two compounds and in the two matrices studied. Extraction percentages were between 78 and 109% and relative standard deviations ≤ 19%. The proposed method is faster than methods described in the literature because showed a few steps. The quantification limits (LOQ) in sewage sludge were 6.4 and 32 ng TEQ kg-1 for 2,3,7,8-TCDF and 2,3,7,8-TCDD, respectively. In soil, LOQs were 0.8 and 8.0 ng TEQ kg-1 for 2,3,7,8-TCDF and 2,3,7,8-TCDD, respectively. These values are lower than the maximum residue limits established by European Legislation. The method was applied to 22 agricultural soil samples from different Brazilian cities and 2,3,7,8-TCDF was detected in one of these samples.

Airborne PCDD/Fs in two e-waste recycling regions after stricter environmental regulations.

Since the 2010s, the authorities of Guangdong province and local governments have enhanced law enforcement and environmental regulations to abolish open burning, acid washing, and other uncontrolled e-waste recycling activities. In this study, ambient air and indoor dust near different kinds of e-waste recycling processes were collected in Guiyu and Qingyuan to investigate the pollution status of particles and polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) after stricter environmental regulations. PM2.5 and PCDD/Fs both showed significantly reduced levels in the two regions compared with the documented data. The congener distribution and principal component analysis results also confirmed the significant differences between the current PCDD/Fs pollution characterizations and the historical ones. The estimated total intake doses via air inhalation and dust ingestion of children in the recycling region of Guiyu ranged from 10 to 32pgTEQ/(kg•day), which far exceeded the tolerable daily intake (TDI) limit (1-4pgTEQ/(kg•day). Although the measurements showed a significant reduction of the release of PCDD/Fs, the pollution status was still considered severe in Guiyu town after stricter regulations were implemented.

Dietary exposure to, and internal organ transfer of, selected halogenated organic compounds in birds eating fish from the Southern Baltic.

The aim of this study was to assess the effect of a marine diet on the accumulation, magnification, maternal transfer and detoxification of chlorinated organic pollutants on the highest trophic level in the Baltic Sea. Results showed that birds eating whole herring received the highest doses of herbicides > pesticides > fungicides > polychlorinated dibenzofurans (PCDFs) > polychlorinated dibenzo-para-dioxins (PCDDs). The toxicity of PCDD/Fs in a penguin's 24-h alimentary exposure was estimated at 7.77 ng TEQ-WHO2005. Among pesticides, the highest concentrations--both in fish and penguin tissue--were those of the pp-DDE isomer. In terms of herbicides, simazine and terbutrine were predominant. The majority of Persistent Organic Pollutants (POPs) underwent accumulation and magnification, and these factors were observed to increase with the birds' age. Guano was found to be an effective means of elimination for all of the studied xenobiotics. Maternal transfer of PCDD/Fs into eggs from internal tissues was most prominent for highly chlorinated dioxins and low chlorinated furans.

Effect of Hybrid Filler, Carbon Black-Lignocellulose, on Fire Hazard Reduction, including PAHs and PCDDs/Fs of Natural Rubber Composites.

The smoke emitted during thermal decomposition of elastomeric composites contains a significant number of carcinogenic and mutagenic compounds from the group of polycyclic aromatic hydrocarbons, PAHs, as well as polychlorinated dibenzo-p-dioxins and furans, PCDDs/Fs. By replacing carbon black with a specific amount of lignocellulose filler, we noticeably reduced the fire hazard caused by elastomeric composites. The lignocellulose filler reduced the parameters associated with the flammability of the tested composites, decreased the smoke emission, and limited the toxicity of gaseous decomposition products expressed as a toximetric indicator and the sum of PAHs and PCDDs/Fs. The natural filler also reduced emission of gases that constitute the basis for determination of the value of the toximetric indicator WLC50SM. The flammability and optical density of the smoke were determined in accordance with the applicable European standards, with the use of a cone calorimeter and a chamber for smoke optical density tests. PCDD/F and PAH were determined using the GCMS-MS technique. The toximetric indicator was determined using the FB-FTIR method (fluidised bed reactor and the infrared spectrum analysis).

Assessment of PCDD/Fs formation and emission characteristics at a municipal solid waste incinerator for one year.

Municipal solid waste incineration (MSWI) has become a predominant emission source of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs). Research focusing on the impact of operating conditions, environmental changes, and operating time on the generation and emissions of PCDD/Fs has not been resolved. To this end, this study tracked and investigated the PCDD/Fs and 17 congener emissions of a typical grate incinerator (800 t/d) continuously for one year. Results showed that the PCDD/Fs concentration at the boiler outlet, stack inlet, and bag filter, including normal and abnormal operation conditions, ranges from 2.11E-02-41.86 ng I-TEQ/Nm3, 7.00E-04-6.76 ng I-TEQ/Nm3, and 1.12-2.90E+03 ng I-TEQ/Nm3, respectively. The 2,3,4,7,8-P5CDF has the highest contribution in all samples, in which a proportion of TEQ ranged from 30 % to 77.73 %. Moreover, by applying the correlation analysis between PCDD/Fs and operating parameters, the emission characteristic is mainly affected by incinerators and boilers during the normal period, and it is affected by the whole MSWI process under abnormal conditions. In addition, the PCDD/Fs emission from the MSWI plant gradually increases from spring to winter. This study is beneficial for supporting the control of PCDD/Fs emission reduction and assisting the operators to optimize the relevant operating parameters of the MSWI plant to achieve a stable and up-to-substandard emissions during the operation period.

Occurrence and carcinogenic potential of airborne PBDD/Fs and PCDD/Fs around a large-scale municipal solid waste incinerator: A long-term passive air sampling study.

Municipal solid waste incinerator (MSWI) not only is deemed one of the uppermost sources of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), but also produces substantial amount of polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) owing to the existence of brominated flame retardants (BFRs) in the waste. So far, however, PBDD/Fs in the vicinal environments of MSWI and their associated risks remain rarely studied. Based on a one-year passive air sampling (PAS) scheme, we investigated airborne PBDD/Fs and PCDD/Fs around a large-scale MSWI that has been operated for multi-years. Both the concentrations of PBDD/Fs and PCDD/Fs showed spatially decreasing trends with the distance away from the MSWI, confirming the influence of the MSWI on the dioxin levels in its ambient air. But its influence on PBDD/Fs was less because PBDD/Fs exhibit lower volatility and therefore lower gaseous concentrations than PCDD/Fs. Compared to the existing global data of airborne PCDD/Fs and PBDD/Fs, our data of the MSWI vicinity were at medium levels, despite PAS samples only represent the concentrations of gaseous dioxins in theory. The seasonal data suggest that meteorological conditions exerted apparent influences over the concentrations and sources of airborne dioxins around the MSWI. As for PCDD/Fs, the MSWI was diagnosed as their uppermost source, followed by local traffic and volatilization/deposition. Whereas the top three PBDD/F sources were related to PBDEs, bromophenol/bromobenzene, and traffic vehicles, respectively. The bioassay-derived TEQs based on the aryl hydrocarbon receptor activation of airborne dioxins around the MSWI were one or two orders of magnitudes higher than their concentration-based TEQs, and the corresponding carcinogenic risks at some MSWI-vicinal sites exceeded the acceptable threshold proposed by the U. S. EPA (10-6 âˆ¼ 10-4) and deserve continuous attention.

Utility of an alternative method (to USEPA Method 1613) for analysis of priority persistent organic pollutants in soil from mixed industrial-suburban areas of Durban, South Africa.

This study evaluates the adequacy of a USEPA Method 1613 alternative analytical method for analysis of persistent organic pollutants (POPs) in soil from the immediate vicinity of industrialized areas in the eThekwini municipal area in South Africa. The objective of this study is in line with the Stockholm Convention Article 11 on research, development, and monitoring. Furthermore, it became imperative to find an alternative analytical procedure to USEPA Method 1613 that could cater to studies conducted in Africa where recent reviews have indicated that most African countries lack the technical and instrumental capacity for performing analysis of dioxin-like compounds according to USEPA Method 1613, which entails the use of high-resolution chromatography and high-resolution mass spectrometry instrumentation. The study aimed to ascertain the utility of an alternative two-dimensional gas chromatography-time of flight mass spectrometry method for analysis of trace-level priority POPs in soil, along with a fast single quadrupole gas chromatography-mass spectrometry method. The analytical methods were applied to the analysis of POPs on soil samples from industrial areas with oil refineries and a pulp and paper manufacturing company, while other samples were collected near the electricity substations and a landfill site. Analytical results showed BDE 209 as the dominant contaminating polybrominated diphenyl ether (concentration ranges from 0.006 to 5.71 ng g-1 ). Polybrominated biphenyls (PBBs) 9, 10, and 49 were the dominant PBBs detected in 78% of the sites tested, although their concentrations were below the limit of quantification (LOQ). Polychlorinated dibenzo-p-dioxins and furans and dioxin-like polychlorinated biphenyls detected could not be quantified above their respective LOQs, indicating that the Durban area has low priority pollutant contamination levels compared to other regions around the world. The methods developed are a starting point that will inform considerations for routine evaluation and management of soil contamination, which plays a vital role in environmental management. Integr Environ Assess Manag 2023;19:749-762. © 2022 SETAC.

Variation in the formation characteristics of PBDD/F, brominated PAH, and PBDE congeners along the secondary copper smelting processes.

Simultaneous determination of 58 congeners of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), brominated polycyclic aromatic hydrocarbons (Br-PAHs), and polybrominated diphenyl ethers (PBDEs) from multiple stages of industrial-scale secondary copper smelting plants was conducted with the aim of understanding their variations and control. In addition to the historical manufacture of PBDEs as brominated flame retardants, this study confirmed that PBDEs can be unintentionally produced and released from the secondary copper industry. The average mass emission factors of PBDD/Fs, PBDEs, and Br-PAHs from different sources were 10.0, 5.21 × 103, and 7.24 × 103 µg t-1, respectively. Therefore, the emission of brominated persistent organic pollutants (POPs) in the secondary copper industry should be of concern. The concentration of brominated POPs increased from the gas cooling stage to stack outlet due to the possible "memory effect" and the regenerated POPs were mainly low-brominated homologs. A comparison of brominated POPs with corresponding chlorinated analogs in the same process indicated that the formation pathway of Br-PAHs was consistent with that of chlorinated PAHs. However, unlike chlorinated dioxins and furans, PBDD/Fs can also be formed from PBDEs as precursors, leading to obvious increases in highly brominated furans. Therefore, inhibiting the unintentional formation of PBDEs is important for controlling brominated POPs emissions.

Instrumental and bioanalytical characterization of dioxin-like activity in sediments from the Yeongsan River and the Nakdong River estuaries, South Korea.

In the present study, we investigated the contamination status of dioxin-like chemicals (DLCs) and potential toxic effects associated with river and coastal sediments from two large estuaries of South Korea. Sediments collected from the Yeongsan River and the Nakdong River estuaries were analyzed for several DLCs, including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), coplanar polychlorinated biphenyls (co-PCBs), and polycyclic aromatic hydrocarbons (PAHs). Greater concentrations of target DLCs (except for PCDDs in Nakdong River) were found in the inland creeks with decreasing trends towards estuarine and coastal areas in both regions. The result indicated that the elevated DLCs were attributable to the surrounding land use activities, such as point sources of industrial and municipal areas from the inland regions. Principal component analysis and positive matrix factorization model revealed that major sources of PCDD/Fs and PAHs in sediments were fly ash and dust, and petroleum and diesel emission, respectively. The dioxin-like activities of the sediments ranged from 0.98 to 88% of the maximal induction elicited by 2,3,7,8-tetrachlorodibenzo-p-dioxin, which generally explained the sedimentary contamination by the target DLCs. Dioxin-like activity in sediments from the artificial lake and inland creek of the Nakdong River Estuary was mostly explained by the targeted DLCs (~75%). However, the contribution of known DLCs from the sediments of the Yeongsan River Estuary was relatively low (~35%) compared to that of the Nakdong River Estuary, suggesting the presence of unknown DLCs in sediments. Overall, the distribution of DLCs quite varied by region, generally reflecting the difference in the surrounding land use activity. In the future, it is needed to study the distribution, sources, and potential ecological effects of unknown toxic substances in coastal sediments.

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in food and human dietary intake: An update of the scientific literature.

It is well established that for non-occupationally exposed populations, dietary intake is, by far, the main way of human exposure to polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs), a family of environmental POPs with a well-known potential toxicity -including carcinogenicity-in humans. We here summarize the results of recent studies (2010-2021) (databases: Scopus and PubMed), focused on determining the levels of PCDD/Fs in food samples of different origins, as well as the dietary intake of these pollutants. We have revised studies conducted in various Asian, American and European countries. However, information is rather limited, with no recent data for most countries over the world. Due to the enormous differences in the methodologies of the studies, to conduct a detailed comparison of the results for the different regions and countries has not been possible. Notwithstanding, where data over time are available, important reductions have been observed. These reductions have been linked to the decreases in the environmental emissions of PCDD/Fs noted in recent years. Interestingly, reductions in the levels of PCDD/Fs in biological tissues are also occurring in parallel. In general, the tolerable daily/weekly/monthly dietary intakes of PCDD/Fs are not being currently exceeded where data are available.

Profiles, spatial distributions and inventory of brominated dioxin and furan emissions from secondary nonferrous smelting industries in China.

Nonferrous metallurgical processes are important sources of carcinogenic polybrominated dibenzo-p-dioxin and dibenzofuran (PBDD/Fs) that transport globally. Studies on the profiles, spatial distributions and inventory of PBDD/F emissions into the atmosphere from nonferrous metallurgical plants are needed for better source control. In this study, field investigations on PBDD/F emissions from typical nonferrous metallurgical plants were conducted to characterize the PBDD/F profiles and derive their emission factors. Based on the PBDD/F profiles, diagnostic ratios of PBDD/Fs for secondary copper, zinc and lead smelting were proposed for identifying the potential sources of PBDD/Fs in environment. The PBDD/F emission factors for the secondary copper, lead, and zinc smelting plants were 0.71, 1.65, and 1.54 µg toxic equivalents/t, respectively. The estimated annual input of PBDD/Fs into atmosphere by secondary nonferrous metallurgical plants in China was 212.4 g by mass and 3511.3 mg by toxic equivalents, which is of significance for further evolving a global inventory. The spatial distribution of PBDD/F emissions from nonferrous metallurgical plants in China was mapped. Larger amounts of PBDD/Fs were emitted in the southeastern coastal region and northern China than elsewhere in China.

Emissions of PAHs, PCDD/Fs, dl-PCBs, chlorophenols and chlorobenzenes from municipal waste incinerator cofiring industrial waste.

Concentrations and distributions of PAHs and chlorinated aromatic compounds including PCDD/Fs, dl-PCBs, chlorophenols (CPs), and chlorobenzenes (CBz) in the municipal waste incinerator are investigated to characterize their formation and emission via intensive stack sampling. In addition, the toxicity of fly ash contribution by PCDD/Fs and dl-PCBs is evaluated in this study. The results reveal that concentrations of PCDD/Fs and dl-PCBs in flue gas are significantly lower than those of CPs, CBz, and PAHs. Additionally, the removal efficiencies of PAHs and chlorinated aromatic compounds achieved with existing air pollution control devices are evaluated, indicating that the removal efficiencies achieved with activated carbon injection + baghouse (95-99%) are higher than those with semi-dry scrubber (SDS). Besides, PCDD/Fs and PCBs TEQ concentrations in SDS and BH ashes are within 1.61-2.66 WHO-TEQ/g and 0.09-0.19 WHO-TEQ/g, respectively. Furthermore, the calculated mass flow rates suggest that the input rate of PCDD/Fs and dl-PCBs of SDS are 60.24 mg/h and 59.74 mg/h, respectively. The mass flow rates of PCDD/Fs and dl-PCBs after SDS in flue gas are 32.47 mg/h and 49.73 mg/h, respectively. However, the discharge rates of PCDD/Fs and dl-PCBs from SDS are 120.60 mg/h and 27.05 mg/h, respectively, indicating that PCDD/Fs are significantly formed within the SDS. PCDD/Fs formation is attributed to the operating temperature of SDS (240 ± 11.5 °C), which is within the temperature window for de novo synthesis. Thus, operating parameters of the APCDs should be optimized to reduce the formation of PAHs and chlorinated aromatic pollutants from MWI.

Characterization of 9 gas chromatography columns by Kovats and Lee retention indices for dioxin analysis.

Polychlorinated dibenzo-p-dioxins and furans offer a complex separation challenge due to their chemical similarity and 5020 possible congeners, including the Br/Cl congeners. Not only are these compounds difficult to separate, but they are also difficult to identify. Expensive reference materials are needed for conventional "dioxin analysis", usually requiring 13C labeled and native compounds. A retention index database offers a potential solution to lower the difficulty and cost to identify dioxins. This study describes the use of Kovats and Lee retention indices for the identification of chlorinated dioxins and furans as well as their brominated and mixed chloro/bromo counterparts. Eight columns were characterized with all 136 tetra through octa substituted chlorinated dioxins and furans as well as 32 brominated and mixed chloro/bromo congeners. Columns were then compared to identify which stationary phases provided the best resolution for critical congeners, like the 2,3,7,8 substituted compounds. Column phase selectivity was also investigated to identify best commercially-available column pairings for confirmatory analyses and GC × GC separations. The Rtx-Dioxin2 and Rxi-17SilMS showed unique selectivity for dioxins and furans and could be used as confirmatory columns or as a powerful GC × GC column set.

Polychlorinated biphenyls are still alarming persistent organic pollutants in marine-origin animal feed (fishmeal).

The presence of polychlorinated biphenyls (PCBs) in feed materials has caused great public concern because PCBs can accumulate in farmed animals, be transferred farm-to-fork and, ultimately, have a detrimental impact on human health. Recently, the occurrence of PCBs in marine environments has garnered scientific attention due to their high levels and potential reproductive threats to marine apex predators. Fishmeal is marine-origin feed material and is susceptible to PCB contamination from the aquatic trophic chain. The present study collected 102 fishmeal samples during 2012-2017 from major global fishmeal production areas (United States, Europe, China, South America and Southeast Asia). The levels of PCBs (26 congeners) were between 0.4 and 19.9 ng g-1 dw (mean: 1.94 ng g-1 dw), with a 75.3% contribution from indicator PCBs on a weight basis. Together with PCDD/Fs, 4.9% of fishmeal exceeded the maximum levels set by the European Commission for dioxin-like compounds (4.0 pg WHO-TEQ/g). The highest PCB levels were found in fishmeal from the U.S. (6.85 ng g-1 dw), which was nearly five times higher than the other four sampling areas. No clear time trends were found for PCBs in fishmeal during the sampling period. Predicted PCB concentrations in farmed fish via fishmeal consumption were between 1.24 and 2.76 ng g-1 dw, which was comparable to PCBs in market fish. When compared to other emerging POPs in the same batches of fishmeal, PCBs were still found to be an alarming class of POPs. Some PCB and PBDE congeners might have similar sources and environmental behaviors.

Halogenated organic compounds in the eggs of aquatic birds from the Gulf of Gdansk and Wloclawek Dam (Poland).

Diet is the major route of exposure to environmental contaminants in biota and, after penetration into an organism, xenobiotics continue to accumulate in the body. In birds the egg-laying process acts as a transfer mechanism for the accumulated pollutants and results in the burdening of the next generation at an early stage of development. This transfer has a strong influence on developmental disorders and even breeding success. With this in mind polybrominated diphenyl ethers (PBDE), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo furans (PCDD/Fs), as well as polychlorinated biphenyls (PCBs), were analyzed in the eggs of aquatic birds from different habitats and with different diet preferences. The highest concentration of PBDE was noted in gull eggs (198.31 ng g-1 dw.) and the lowest in tern eggs (sandwich tern: 76.96 ng g-1 dw.; common tern: 113.73 ng g-1 dw). Deca-BDE was detected only in herring gull eggs from the Wloclawek reservoir. PCDDF/s were found in the eggs of terns from the southern coast of the Baltic Sea and gulls from an inland reservoir (dam) on the River Vistula close to the town of Wloclawek. The highest toxicity (birds Toxic Equivalent Factor) was found in the eggs of terns (sandwich tern - 93.97 pg g-1 dw., common tern - 68.35 pg g-1 dw.), and this was found to be several times higher than in herring gull eggs (18.80 pg g-1 dw.). Non-dioxin like PCBs were ten times higher than other analyzed PCB congeners, but the congener pattern was similar to other studies.

Contributions of dioxins and furans to the urban sediment signature: The role of atmospheric particles.

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-p-furans (PCDF) are widely distributed in the environment. The diverse production processes that form these compounds lead to a range of chemical signatures although weathering may cause changes to these signature over time and with increasing distance from their origin. Chemical signatures in sediments based on 17 PCDD/Fs were developed in Concepcion, a Chilean city in the middle of a complex hydrological system which contains several small urban freshwater bodies and the River Bio-Bio. The region has numerous industrial and domestic activities that may contribute PCDD/Fs to the environment. Sediments from urban lakes had higher concentrations of dioxins and furans (mean=941ng·kg-1) than either a remote lake (335ng·kg-1) located 32km from the city or marine samples (mean=124ng·kg-1). Up to 85% of the compounds present in all sediment samples could be explained by the chemical signature associated with airborne particulates leaving only 15-30% of the chemical signature potentially arising from other sources. The remote lake had higher proportions of the less-chlorinated compounds compared to the urban samples.

Concentrations of trace elements and PCDD/Fs around a municipal solid waste incinerator in Girona (Catalonia, Spain). Human health risks for the population living in the neighborhood.

Previously to the modernization of the municipal solid waste incinerator (MSWI) of Campdorà (Girona, Catalonia, Spain) two sampling campaigns (2015 and 2016) were conducted. In each campaign, 8 soil and 4 air samples (PM10 and total particle phase and gas phase) were collected. The levels of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Sn, Tl and V, and PCDD/Fs were analysed at different distances and wind directions around the MSWI. Environmental levels of trace elements and PCDD/Fs were used to assess exposure and health risks (carcinogenic and non-carcinogenic) for the population living around the facility. In soils, no significant differences were observed for trace elements and PCDD/Fs between both campaigns. In air, significant higher levels of As, Cd, Co, Mn, Ni, Pb, Tl and V were detected in 2016. Regarding soil levels, only Cd (distances) and As, Cu, Mn, and Ni (wind directions) showed significant differences. No differences were noted in the concentrations of trace elements and PCDD/Fs in air levels with respect to distances and directions to the MSWI. No differences were registered in air levels (elements and PCDD/Fs) between points influenced by MSWI emissions and background point. However some differences in congener profile were noted regarding from where back-trajectories come from (HYSPLIT model results), pointing some influence of Barcelona metropolitan area. The concentrations of trace elements and PCDD/Fs were similar -or even lower- than those reported around other MSWIs in Catalonia and various countries. Non-carcinogenic risks were below the safety limit (HQ<1). In turn, carcinogenic risks due to exposure to trace elements and PCDD/Fs were in acceptable ranges, according to national and international standard regulations.

Unregulated pollutant emissions from on-road vehicles in China, 1999-2014.

Multi-year (1999-2014) vehicular unregulated pollutants emissions in China, including SO2, CH4, N2O, NH3, Indeno(1,2,3-cd)pyrene (IPY), Benzo(k)fluoranthene (BkF), Benzo(b)fluoranthene (BbF), Benzo(a)pyrene (BaP), dioxins and furans, were estimated based on emission factors calculated by COPERT. The inter-annual trends, correlation with GDP and population, spatial distribution characteristics, contributions from various vehicle types for the ten pollutants emissions were analyzed. Results showed that the emissions of the above ten pollutants changed from approximately 576.9Gg, 130.0Gg, 8.1Gg, 2.1Gg, 1.0Mg, 1.1Mg, 1.4Mg, 0.5Mg, 7.4g and 15.6g in 1999 to 193.8Gg, 171.1Gg, 79.1Gg, 117.8Gg, 3.5Mg, 6.7Mg, 6.8Mg, 2.9Mg, 37.6g and 79.1g in 2014, respectively. Implementation of stringent sulfur content limit during the past decade reduced approximately 94.4% of the SO2 emission in 2014. CH4 and N2O increased from 1999 to 2011, but began to decrease since 2012; NH3 emission had the highest annual average change rate (35.5%) from 1999 to 2014; PAHs, dioxins and furans increased continuously during the past decade. The vehicular emissions were higher in Guangdong, Shandong, Henan, Jiangsu, Zhejiang and Hebei. Good linear correlation between vehicular emissions and GDP was found (except SO2); in the provinces/municipalities with higher population density, the emission density was also larger, indicating more significant vehicular emissions' potential damage on human health. HDT and PC, PC and MC, PC and BUS were the major contributors to SO2, CH4, N2O emissions, respectively. In 2014, PC was the dominant contributor to NH3 emission; PC, BUS and HDT had higher fraction in the total IPY and BaP emissions; HDT was the major contributor to BkF and BbF emissions. In addition, the uncertainties of estimated emissions were also analyzed based on Monte Carlo simulation.