Modification of an environmental surveillance program to monitor PCDD/Fs and metals around a municipal solid waste incinerator

Twenty-year trends and exposure assessment of polychlorinated dibenzodioxins and dibenzofurans in human serum from the Seoul citizens

This study investigated polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in air (n = 108) and human serum (n = 1802) samples collected over 20 years to evaluate the long-term exposure to PCDD/Fs and health effects on the Korean general population. The serum PCDD/F levels were higher in males than in females and were significantly correlated with age, body mass index, and manifestation of diabetes mellitus. From 2000 to 2019, the PCDD/F levels declined by 96% in the air, but only by 36% in the serum, because PCDD/Fs are relatively stable in the human body and are exposed to humans after PCDD/Fs are distributed and migrated in various environmental matrices. The PCDD/F levels in other environmental matrices have also decreased at rates that differed among the matrices due to the different retention times and changes in continuous input of contaminants. As PCDD/Fs migrate from environmental matrices to the human body, the fraction of PCDDs increased whereas that of PCDFs decreased because of their relatively short half-lives. This study provides a concrete evidence that PCDD/F emissions by national regulations can achieve long-term reduction in human exposure. To the best of our knowledge, this is the longest and largest study to evaluate the long-term trends and annual changes of PCDD/Fs in the atmosphere and human serum, simultaneously.

A follow-up study on the characterization and health risk assessment of heavy metals in ambient air particles emitted from a municipal waste incinerator in Zhejiang, China

To confirm our hypothesis that inhalation might be the primary exposure route of heavy metals for children living in proximity to a municipal waste incinerator (MWI), we conducted a one-year follow up study to characterize the distributions of heavy metals featured in different types of ambient air particles, including PM₁, PM_2.5 and PM₁₀, at two exposure sites near the MWI (E1 and E2) and one control site (C) in Zhejiang, China. Particle samples were collected by a mid-volume sampler and heavy metals were determined by the inductively coupled plasma mass spectrometry method. The mass concentrations of PM₁, PM_2.5 and PM₁₀ were 52.0, 85.8 and 100.3 μg/m³ at E1 site, while the concentrations were 40.2, 92.1 and 106.6 μg/m³ at E2 site and 33.4, 55.6 and 66.1 μg/m³ at C site, respectively. Both E1 and E2 had higher PM₁, PM_2.5 and PM₁₀ levels than C site. The levels of pollution were season dependent, with autumn having the highest levels of PM₁, PM_2.5 and PM₁₀ across all three sampling sites. Regarding the distributions of heavy metals, Pb accounted for the majority of the seven metals in all groups, ranging from 43.2% to 51.3%, followed by Mn that ranged from 22.0% to 32.0%. The Pb levels of PM₁, PM_2.5 and PM₁₀ in the MWI area were 22.6, 34.2 and 36.2 ng/m³, respectively, while Mn levels were 10.1, 20.0 and 23.5 ng/m³, respectively. The health risk assessment results suggested that residents were suffering high non-carcinogenic risk posed by MWI-emitted particle-bound toxic metals, as well as the high lifetime carcinogenic risk. This study revealed that ambient air, no matter whether near or far away from an MWI, bore more PM₁, PM_2.5 and PM₁₀ particles than general, non-polluted ambient air, especially in autumn.

Characteristics of PCDD/Fs and metals in surface soil around an iron and steel plant in North China Plain

In this study, the level of 18 species of metals and 17 species of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were monitored in surface soil samples around an iron and steel plant in the North China Plain. The concentration of PCDD/Fs and metals in the soil ranged from 0.16 to 4.5 ng I-TEQ/kg and 1.2 to 24,182.2 mg/kg, respectively. Furthermore, the prevailing winds were confirmed to influence the spatial distribution of PCDD/Fs and metals concentrations. The highest concentration of PCDD/Fs was located in downwind soil sample 4 (S4), which showed more than 50% of PCDFs in the total PCDD/Fs, and high levels of lower chlorinated PCDFs. Moreover, the highest Cd and Zn concentrations of 18.1 and 2647.8 mg/kg, respectively, were observed in soil collected from S4, which were significantly above the government guidelines for metals in farmland soil. Our results show that a group of metals (Mg, Al, K, Fe, Cu, Zn, Se, Cd, Sb and Pb) was well correlated with all PCDD/Fs except three (OCDD, 1,2,3,4,6,7,8-HpCDD and 1,2,3,7,8,9-HxCDD), which likely originated from iron and steel processes. Additionally, Pb, Zn, Cd and all polychlorinated dibenzofurans showed a good correlation and grouped in one cluster, suggesting anthropogenic sources from sintering process. Therefore, the metallic characteristics in soil, especially the Pb, Zn and Cd tracers, implied evidence of the accumulation of PCDD/Fs from sinter plants.

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.

High cancer risks by exposure to PCDD/Fs in the neighborhood of an Integrated Waste Management Facility

In 2014, we conducted a study aimed at screening the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and various trace elements in air and soil samples collected in an urban area of Sant Adrià de Besòs (Barcelona, Spain) in the vicinity of an Integrated Waste Management Facility (IWMF). It consists of a mechanical-biological treatment plant (MBT) and an old municipal solid waste incinerator (MSWI). Human health risks for the population living in the area were also assessed. The most worrying result was the high cancer risks estimated for the area (2.5×10^-6). In March 2017, we have carried out a new survey to check if the authorities had taken the necessary and urgent measures to reduce the environmental concentrations of PCDD/Fs -and the human health risks- until acceptable levels. Although the concentrations of PCDD/Fs in soils are currently lower (mean value: 1.66 vs. 3.6ng WHO-TEQ/kg in 2014), they are still are notably higher than those found near other MSWIs of Catalonia. In turn, the levels of PCDD/Fs in air are even higher than in 2014 (mean value: 0.044 vs. 0.026pgWHO-TEQ/m³ in 2014), being also the highest detected in similar zones of Catalonia. The current cancer risk due to PCDD/F exposure for the residents in the neighborhood of the IWMF is 2.3×10^-6, a worrying fact as the 10^-6 threshold continues to be exceeded.

Environmental trends of metals and PCDD/Fs around a cement plant after alternative fuel implementation: human health risk assessment

This study aimed at evaluating the potential impact of a cement plant after 4 years of the employment of alternative fuel. In June 2015, concentrations of PCDD/Fs and metals were determined in soils, vegetation and air in order to measure potential changes with respect to previous surveys before (July 2011) and after (June 2013) the employment of alternative fuel. Risks to human health were also assessed. In soils, metal levels were similar to those observed in June 2013 (p > 0.05). In comparison with July 2011, the increment was only statistically significant for As and Cd (p < 0.05). A notable increase in levels of PCDD/Fs was noted when current levels in soils (1.14 ng WHO-TEQ per kg) were compared with those observed in July 2011 (0.37 ng WHO-TEQ per kg) (p > 0.05) and June 2013 (0.41 ng WHO-TEQ per kg) (p < 0.05). This increase was mainly caused by the increase in PCDD/F levels at one sampling site, which showed the heterogeneity of PCDD/F levels in soils, possibly as a result of different point emissions over the years. On the other hand, temporal trends in levels of metals and PCDD/Fs in vegetation showed a clear decrease, which indicated that the particle fraction of these pollutants would potentially be removed from leaf surfaces by wash-off. In air, levels were similar to those found in previous surveys. The results of PCA showed that the change in fuel had not affected the environmental profiles of metals and PCDD/Fs around the cement plant. The exposure of the population living in the surroundings of the plant was measured and it was shown that diet was the major contributor for both metals and PCDD/Fs, with percentages of over 97%, the only exceptions being As and Pb, for which dietary intake accounted for 43% and 71% of the total exposure, respectively. Environmental non-cancer and cancer risks were within the limits considered as acceptable by international standards.

Exposure assessment of PCDD/Fs for the population living in the vicinity of municipal waste incinerator: Additional exposure via local vegetable consumption

While the exposure assessment of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/Fs) for people living in the vicinity of municipal solid waste incinerators (MSWI) has been investigated, indirect exposure to MSWI-emitted PCDD/Fs via consumption of local foods has not been well assessed. In this study, the PCDD/F concentration in the local vegetables grown near a MSWI located in Shenzhen, South China, was determined to be 0.92 ± 0.59 pg/g wet weight (ww), significantly higher than that (0.25 ± 0.35 pg/g ww) in commercial vegetables (p < 0.05). The PCDD/F concentrations in Banyan leaf (Ficus microcarpa) samples collected from 5 sampling sites at 1 km intervals from the MSWI were found to be significantly decreased with increasing distance, suggesting that the local plants would be impacted by emissions from the MSWI. The exposure assessment of PCDD/Fs for the population living in the vicinity of MSWI was carried out by simultaneously analyzing PCDD/Fs in other food groups that were commonly consumed by the residents. If only the local vegetables were consumed and other foods were acquired commercially, the total dietary intake for a general adult was 0.94 ± 0.41 pg TEQ/kg bw/day, of which consumption of local vegetables accounted for 52.3%. If all foods consumed including vegetables were from a commercial source, the total dietary intake was 0.56 ± 0.30 pg TEQ/kg bw/day, of which consumption of commercial vegetables accounted for 20.1%. The present study for the first time reported the additional human exposure to PCDD/Fs via consumption of local vegetables impacted by emissions from MSWI.

PCDD/F contamination on surface soil in the vicinity of a hazardous waste incinerator: is it possible a different trend?

This study is the first to investigate the contamination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) on surface soils in the vicinity of the first hazardous waste incinerator of Turkey. In the study, 24 soil samples were taken from a 1625-m-radius circle whose center is the stack of the incinerator. This process was repeated 1 year later. Since the acquired average PCDD/F concentrations of the two sampling campaigns (0.05 and 0.02 ng WHO-toxic equivalent (TEQ)/kg) were meaningfully low compared to the related literatures, a new sampling campaign was carried out to control this inconsistency, but this time in a foreign laboratory (0.56 ng WHO-TEQ/kg). In the same period, eight gas samples were taken from the stack under different operational conditions of the facility. According to the evaluations of the findings, the geographical-meteorological data of the study area and the specific operational conditions of the facility corroborate the concentrations of the first and the second soil samplings rather than the third one. The major underlying reason for the inconsistency of the soil concentrations may be the fact that the data analysis procedures used by the laboratories are different. The author suggests a hypothesis which argues that the soils in the vicinity of a hazardous waste incinerator may have significantly lower concentration levels than in related literatures.

Composition profiles, monthly changes and health risk of PCDD/F in fly ash discharged from a municipal solid waste incinerator (MSWI) in Northeast China

Monthly changes and health risk of PCDD/Fs in fly ash which was one of hazardous wastes from municipal solid waste incinerator (MSWI) were studied.

Two Decades of Environmental Surveillance in the Vicinity of a Waste Incinerator: Human Health Risks Associated with Metals and PCDD/Fs

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), as well as the levels of a number of heavy metals, have been periodically measured in samples of soil and vegetation collected around a municipal solid waste incinerator (MSWI) in Tarragona (Catalonia, Spain) for approximately 20 years. Since 2007, the levels of the above-mentioned pollutants have also been determined in air samples by means of either active or passive samplers. In the present study, data regarding the environmental impact of the MSWI, in terms of PCDD/Fs and heavy metals, are updated. The temporal trends of these pollutants were evaluated by comparison with data from previous surveys. In the current survey (2013-2014), mean concentrations of PCDD/Fs in soil, vegetation, and air were 0.63 ng I-TEQ/g, 0.07 ng I-TEQ/g, and 10.1 fg WHO-TEQ/m(3), respectively. Decreases of 47 and 35 % of PCDD/Fs in soil and vegetation, respectively, were observed in relation to the background study (1999). Regarding air samples, a slight temporal decrease of the PCDD/F levels was also found with the remaining concentrations staying nearly constant through time. With respect to metals, notable fluctuations in the concentrations were noted, being dependent on each specific environmental monitor. Overall, the current exposure to PCDD/Fs and metals does not mean any additional health risks for the population living near the facility. In conclusion, the results of the present study show that the environmental impact of the Tarragona MSWI is not significant, in terms of PCDD/Fs and heavy metals, after >20 years of continuous operation.

Environmental levels of PCDD/Fs and metals around a cement plant in Catalonia, Spain, before and after alternative fuel implementation. Assessment of human health risks

The concentrations of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Sn, Tl, V, and Zn, and the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans were determined in samples of soil, vegetation, and air, collected in the vicinity of a cement plant (Catalonia, Spain), before (January 2011 and July 2011) and after (January 2012 and June 2013) alternative fuel partial substitution (fossil fuels by sewage sludge). Seven sampling points were selected at different directions and distances to the facility including two background sampling points. The results were used to assess the health risk assessment for the population living near the facility. Only few significant differences were found before and after alternative fuel partial substitution (Mn in soils and Cd in vegetation). Non-carcinogenic risks were below the safety threshold (HQ<1), while carcinogenic risks were below 10(-5), or exceeding slightly that value, always in the range considered as assumable (10(-6)-10(-4)).

Seasonal surveillance of airborne PCDD/Fs, PCBs and PCNs using passive samplers to assess human health risks

This study aimed at determining the air concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) near a municipal solid waste incinerator (MSWI) in Tarragona (Catalonia, Spain) by means of passive air sampling. Seasonal trends in airborne levels were also assessed by comparing the results of 6-month surveys conducted between spring of 2010 and autumn of 2011. These data were used to estimate exposure for the population living nearby and to evaluate the non-carcinogenic and carcinogenic risks associated to inhalation of those persistent organic pollutants (POPs). No seasonal differences were noted in POP concentrations among the sampling campaigns. The highest levels of PCDD/Fs were found in the 3rd campaign, while significantly lower levels of PCNs were found in the 4th survey. The concentrations of PCDD/F and PCB congeners, as well as those of PCN homologues, did not change significantly with time, which indicates that the MSWI does not have an important influence on the surrounding environment. The levels of POPs near the facility are at the lower part of the range, when compared with data from the scientific literature. Consequently, the current levels of POPs in ambient air around the MSWI are associated to a low human exposure to PCDD/Fs, PCBs and PCNs, which means a lack of additional health risks for the local population. In addition, passive samplers have been confirmed to be a good tool for local environmental monitoring, as well as a good method to study seasonal trends in POP concentrations in air.

Body burden monitoring of dioxins and other organic substances in workers at a hazardous waste incinerator

The construction in Constantí (Tarragona County, Catalonia) of the first, and up till now the only hazardous waste incinerator (HWI) in Spain, finished in 1999. In this study, we measured the concentrations of a number of organic substances determined in blood and urine of the HWI workers. Samples of 18 men and 9 women, classified according to their respective workplaces, were collected in 2011, after approximately 12 years of regular operations in the facility. The current results were compared with those of the baseline survey, as well as with the most recent surveys performed in 2008, 2009 and 2010. Plasma analyses were carried out for hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs 28, 52, 101, 138, 153, and 180) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), while the levels of 2,4- and 2,5-dichlorophenol (DCP), 2,4,5- and 2,4,6-trichlorophenol (TCP), pentachlorophenol (PCP) and 1-hydroxypyrene (1-HP) were measured in urine samples. In plasma, the mean concentrations were the following: 10.8μg/kg lipid for HCB; 0.8μg/kg lipid for PCB28; 0.3μg/kg lipid for PCB52; 0.5μg/kg lipid for PCB101; 42.2μg/kg lipid for PCB138; 18.5μg/kg lipid for PCB153, and 51.2μg/kg lipid for PCB180. For PCDD/Fs, the mean concentration was 4.6ng I-TEQ/kg lipid (4.7ng WHO-TEQ/kg lipid). These levels, as well as those found in urine samples, are in agreement with the data of previous surveys performed in the same area. The current results in HWI workers do not show any evident sign of occupational exposure to PCDD/Fs and other organic substances. However, these results must be considered only as an indication of potential exposure, as the study presents notable limitations, such as the reduced number of participants and the lack of data relative to the air concentrations of chemicals. Consequently, general conclusions cannot be derived and the results should not be used as a basis for the implementation of industrial hygiene measures in other HWIs.

In vitro tests to assess toxic effects of airborne PM(10) samples. Correlation with metals and chlorinated dioxins and furans

Inhalation is an important exposure pathway to airborne pollutants such as heavy metals, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and particulate matter. Chronic exposure to those chemicals, which form part of complex environmental mixtures, may mean important human health risks. In the present study, the suitability of different in vitro tests to evaluate the toxic effects of air PM(10) pollutants is investigated. In addition, it is also assessed how to distinguish the contribution of chemical pollutants to toxicity. Sixty-three air samples were collected in various areas of Catalonia (Spain), and the levels of ecotoxicity, cytotoxicity and genotoxicity were evaluated. Aqueous acidic extractions of quartz fiber filters, where PM(10) had been retained, were performed. The photo-luminescent bacteria Vibrio fischeri (Microtox®) bioassay was performed to assess ecotoxicity. Moreover, MTT and Comet Assays, both using human lung epithelial cells A549 as target cells, were applied to assess the cytotoxicity and genotoxicity of air samples, respectively. The results show that Microtox® is an excellent screening test to perform a first evaluation of air quality, as it presented a significant correlation with chemical contaminants, contrasting with MTT Assay. Although none of the samples exhibited genotoxicity, a high correlation was found between this in vitro test and carcinogenic agents. Urban samples from traffic-impacted areas would be significantly more toxic. Finally, environmental temperature was identified as a key parameter, as higher values of ecotoxicity were found in winter.

Long-term monitoring of dioxins and furans near a municipal solid waste incinerator: human health risks

Since 1996, a wide surveillance programme has been developed to get overall information on the impact of a municipal solid waste incinerator (MSWI) in Tarragona (Catalonia, Spain). The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) have been periodically measured in soil and vegetation samples collected at locations in the incinerator surroundings. Furthermore, air PCDD/F levels have been also monitored by using active and passive sampling devices, generating a huge amount of information regarding the environmental status of the zone. In the last survey (2009-2010), mean PCDD/F levels in vegetation, soil and air were 0.06 ng I-TEQ kg(-1), 0.58 ng I-TEQ kg(-1) and 10.5 fg WHO-TEQ m(-3), respectively. Both soil and herbage showed a notable reduction in the PCDD/F concentrations in comparison with the baseline study, with this decrease only being significant for soils. In contrast, PCDD/F values in air remained similar during the whole assessment period. Human exposure to PCDD/Fs was evaluated under different scenarios, and the associated non-carcinogenic and carcinogenic risks were assessed. The hazard quotient was below unity in all cases, while cancer risks were under 10(-6), which is lower than the maximum recommended guidelines. The current results clearly show that the MSWI of Tarragona does not produce additional health risks for the population living nearby.

The aqueous solubility of some herbicidal by-side toxic impurities: predicted data of the 399 chlorinated trans-azoxybenzene congeners

The quantitative structure - property relationship (QSPR) and the artificial neural networks (ANNs) methods were used to estimate aqueous solubility (log S and μg/L) of polychlorinated trans-azoxybenzenes (PCt-ABs). These QSPR and ANN models are based on geometry optimalization and quantum-chemical structural descriptors, which were computed on the level of density functional theory (DFT) using B3LYP functional and 6-311++G** basis set in Gaussian 03 software and the semi-empirical quantum chemistry method for property parameterization (RM1) in the molecular orbital package (MOPAC) software. The predicted solubility of PCt-AOBs by RM1 and DFT models and depending on a congener varied within a homologue class between 47-19498 and 371-1738 μg/L for Mono-; 33-11481 and 7.9-3630 μg/L for Di-; 6.1-4786 and 4.7-12882 μg/L for Tri-; 1.3-1174 and 0.3-14791 μg/L for Tetra-; 0.4-646 and 0.1-38904 μg/L for Penta-; 0.1-155 and 0.2-63096 μg/L for Hexa-; 0.2-27 and 0.1-646 μg/L for Hepta-; < 0.1-6.2 and 0.8-282 μg/L for Octa-; 0.6-2.6 and 0.8-12 μg/L for NonaCt-AOBs; and 1.2 and 0.5 μg/L for DecaCt-AOB, respectively. Both computational models used were characterized by good predictive abilities and small errors, while calculations by RM1 method were highly competitive compared to a much more time-consuming and expensive method by DFT.

Estimation of K(OA) values of 209 polychlorinated trans-azobenzenes by PM6 and DFT methods

The octanol-air partition coefficients (K(OA)) of all 209 PCt-ABs were determined computationally to fill gaps on their environmentally relevant physical and chemical properties. These properties have been determined using two computational approaches: the semi-empirical quantum chemistry method for property parameterization (PM6) of the molecular orbital package (MOPAC) and density functional theory (DFT) method using B3LYP functional and 6-311++G** basis set in Gaussian 03 software and artificial neural network (ANN) predicting abilities. Both computational methods enabled estimation of log K(OA) partition coefficients of PCt-ABs with a similar accuracy and precision. The PM6 method compared to DFT was highly superior because it requires much less time, manpower and cost of hardware. The determined log K(OA) values of the investigated PCt-ABs for standard condition (25 °C) varied between 8.30 and 8.75 for Mono-; 8.71 and 9.92 for Di-; 9.58 and 10.72 for Tri-; 10.11 and 11.34 for Tetra-, 10.83 and 11.85 for Penta-; 11.24 and 12.36 for Hexa-; 11.87 and 12.66 for Hepta-; 12.31 and 12.97 for Octa-; 12.89 and 13.21 for Nona-Ct-ABs; and 13.17- and 13.49 for Deca-Ct-AB. PCt-ABs, in view of these log K(OA) values, can be classified as compounds of relatively low (Mono-, Di- and some of Tri- Ct-ABs with values of log K(OA) around 8 to 10) environmental mobility (most of Tri- to Nona-Ct-ABs and Deca-Ct-AB homologues with values of log K(OA) >10), and with a potential to be adsorbed by soil particles.

Levels and sources of planar and non-planar PCBs in pine needles across Poland

Under a small project, one-year-old Scots Pine needles collected from 25 spatially distant sites were examined in monitoring the extent of environmental diffusion and possible sources of polychlorinated biphenyls (PCBs) in ambient air, their depositions and uptake by plants in Poland. The congener-specific determination of planar and non-planar chlorobiphenyls was achieved by isotope dilution HRGC-HRMS method after a highly refined extraction on multi-layer column of silica gel and alumina layer and clean-up, and fractionations, followed by Hypercarb-HPLC and PYE-HPLC sub-fractionation steps. Contents of 117 chlorobiphenyls determined in pine needles varied for the 25 sites studied and is between 2.7 and 49 ng/g wet weight. The PCBs pollution and congener-specific composition of pine needles to some degree varied according to the site or region surveyed depending on population density and industrialization. Many of the country-side areas showed lower concentrations between 2.7 and 8.9 ng/g ww. Pine needles in areas close to well populated and industrial regions of Opole, Kutno, Włocławek and Dębica showed the highest PCB pollution with concentrations varying between 30 and 49 ng/g ww. The Kutno site showed the highest pollution and this fact probably can be explained by possible emission from transformer manufactures located at some distance west of the Kutno area. Factor analysis (FA) and depending on the site revealed on relationship of PCBs composition of pine needles both with highly chlorinated PCB constituents of the mixtures such as Chlorofen, Aroclor 1254, Aroclor 1268 and Sovol but also of lower chlorinated PCB constituents of Aroclor 1242, Aroclor 1248, Clophen A40 or Delor 103. Thermal processes were considered a less significant source of PCBs in ambient air over Poland compared to evaporative sources related to technical PCB formulations. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of Environmental Science and Health: Part A to view the free supplemental file.

Prediction of subcooled vapor pressures (log PL) of 399 polychlorinated trans-azoxybenzenes by using the QSPR and ANN approach

Environmentally relevant partitioning properties such as the sub-cooled vapor pressures (log PL) have been predicted for 399 congeners of chloro-trans-azoxybenzene (C-t-AOBs) by two computational methods. The quantitative structure-property relationship (QSPR), an approach which is based on geometry optimalization and quantum-chemical structural descriptors in RM1 and DFT methods and artificial neural networks (ANNs), an approach that predicts abilities that give similar results of estimated log P(L) and the accuracy of the methods was also similar. The RM1 method was less time consuming and less costly compared to calculations by the DFT method. Estimated from the RM1 and DFT methods of log P(L) values of 399 Ct-AOBs varied between -1.98 to -0.93 and -1.83 to -0.79 for Mono-, 3.12 to -1.46 and -3.00 to -1.46 for Di-, -4.03 to -1.39 and -3.53 to -1.67 for Tri-, -4.75 to -2.33 and -4.59 to -1.91 for Tetra-, -5.37 to -2.59 and -5.42 to -2.09 for Penta-, -5.82 to -2.88 and -5.66 to -2.58 for Hexa-, -5.88 to -3.24 and -5.60 to -2.93 for Hepta-, -6.28 to -4.33 and -5.60 to -4.29 for Octa-, -6.54 to -5.28 and -5.66 to -4.93 for NonaCt-AOBs, and -6.59 and -5.61 for DecaCt-AOB. According to a common classification of environmental contaminants and by sub-cooled vapor pressure values, MonoCt-AOBs and a few of the Di- and TriCt-AOBs (log P(L)from -2 to 0) fall into the group of compounds that are relatively well mobile in the ambient environment, while most of the Di- to HeptaCt-AOBs (log P(L) < -4 to -2) mobility is relatively weak. Octa- and NonaCt-AOBs and DecaCt-AOB (log P(L) < -4) are also weak mobile contaminants.

QSPR models for prediction of the soil sorption coefficient (log KOC) values of 209 polychlorinated trans-azobenzenes (PCt-ABs)

The values of the soil sorption coefficient (K(OC)) have been computed for 209 environmentally relevant trans polychlorinated azobenzenes (PCABs) lacking experimental partitioning data. The quantitative structure-property relationship (QSPR) approach and artificial neural networks (ANN) predictive ability used in models based on geometry optimalization and quantum-chemical structural descriptors, which were computed on the level of density functional theory (DFT) using B3LYP functional and 6-311++G** basis set and of the semi-empirical quantum chemistry method for property parameterization (PM6) of the molecular orbital package (MOPAC). An experimentally available data on physical and chemical properties of PCDD/Fs and PCBs were used as reference data for the QSPR models and ANNs predictions in this study. Both calculation methods gave similar results in term of absolute log K(OC) values, while the PM6 model generated in the MOPAC was a much more efficient compared to the DFT model in GAUSSIAN. The estimated values of log K(OC) varied between 4.93 and 5.62 for mono-, 5.27 and 7.46 for di-, 6.46 and 8.09 for tri-, 6.65 and 9.11 for tetra-, 6.75 and 9.68 for penta-, 6.44 and 10.24 for hexa-, 7.00 and 10.36 for hepta-, 7.09 and 9.82 octa-, 8.94 and 9.71 for nona-Ct-ABs, and 9.26 and 9.34 for deca-Ct-AB. Because of high log K(OC) values PCt-ABs could be classified as compounds with high affinity to the particles of soil, sediments and organic matter.

Monitoring environmental levels of trace elements near a hazardous waste incinerator: human health risks after a decade of regular operations

In 1998, we initiated an environmental surveillance program of the only hazardous waste incinerator (HWI) in Spain. The concentrations of a number of metals (As, Be, Cd, Cr, Hg, Mn, Ni, Pb, Sn, Tl, and V) were analyzed in soil and vegetation samples collected around the facility. Since then, periodical measurements of these same elements have been performed in both matrices. In 2009 and 2010, soil and vegetation samples were again collected, and the levels of the above elements were determined. In general terms, the temporal trends in metal concentrations were not homogeneous, showing significant changes between the baseline and the latest surveys. Metal levels in soil and herbage samples analyzed in the current survey were similar to recent data reported for other urban and industrial areas, being notably lower than the reference values set by national regulatory organisms. Moreover, more than 10 years after regular operations of the HWI, exposure to metals would not mean, either now or in past surveys, any carcinogenic or non-carcinogenic health risks for the population living in the neighborhood.

Levels of chemical and microbiological pollutants in the vicinity of a waste incineration plant and human health risks: temporal trends

In 2007, a program was initiated to monitor air levels of volatile organic compounds (VOCs) and bioaerosols in the vicinity of a municipal solid waste incinerator (MSWI) (Tarragona, Catalonia, Spain). To investigate the temporal trends of chemical and microbiological pollutants, four 6-monthly campaigns were performed. Air samples were collected at different distances and directions from the facility, as well as in reference sites. In general terms, the concentrations of microbiological agents were very similar to those found in urban zones worldwide. The seasonal evaluation of the results showed higher levels of gram-negative bacteria in winter, contrasting with the increase of the airborne amount of total bacteria in summer. On the other hand, the concentrations of VOCs (mean range: 7.6-18.2 μg m(-3)) were typical of suburban zones. The current exposure to those compounds should not mean additional health risks for the population living nearby.

Long-term environmental monitoring of persistent organic pollutants and metals in a chemical/petrochemical area: human health risks

Organic pollutants such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polycyclic aromatic hydrocarbons (PAHs), as well as some metals are periodically monitored in soil and vegetation samples collected in Tarragona County (Spain). We here report the temporal trends of the concentrations of the above pollutants between the initial survey (2002) and that recently (2009) performed. The area under evaluation was divided into 4 sections (chemical, petrochemical, urban/residential and unpolluted). In general terms, urban soils presented the highest concentrations of PCDD/Fs, PCNs and PAHs, confirming that traffic is a very important emission source of these pollutants. In addition, substantially higher levels of PAHs and some metals were found in vegetation samples from the petrochemical complex. The assessment of health risks of these contaminants indicated that the current concentrations of micropollutants did not mean additional non-carcinogenic or cancer risks for the population living in the zone.

Use of sewage sludge as secondary fuel in a cement plant: human health risks

Since 2008, sewage sludge is being used as alternative fuel in a cement plant placed in Vallcarca (Catalonia, Spain). To evaluate the temporal trend of the environmental levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and a number of metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sn, Tl, V, and Zn), as well as the potentially associated human health risks, samples of soil, herbage, and air were collected around the facility, after approximately one year of the permanent partial substitution of fuel. The temporal evolution of the pollutant levels was assessed by comparing the measured concentrations (2009) with those from samples collected in previous surveys (2003 and 2006) at the same sampling sites. The concentrations of PCDD/Fs in herbage and soil were 0.10 and 1.11 ng I-TEQ·kg⁻¹ dw, respectively, values very similar to those found in our previous surveys. For metals, although a clear tendency could not be observed, there were fluctuations through time. In this study, the levels of metals, which had not been analyzed in previous campaigns, were also determined in air, additionally to soil and vegetation. Airborne metal concentrations were similar to those found in other industrial areas worldwide. The human health risks for the population living around the cement plant were comparable to those obtained in previous studies, when petroleum coke was exclusively used as combustible, being in both cases tolerable according to the international standards.

Levels of metals and PCDD/Fs in the vicinity of a cement plant: assessment of human health risks

In April 2009, a cement plant located in Sant Feliu de Llobregat (Catalonia, NE Spain) stopped its normal operations. To establish the environmental impact of the facility and the health risks for the population living in the neighbourhood, the concentrations of a number of metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were determined in soil, vegetation and air samples in three different surveys, which were carried out before and after the facility stopped the cement production. The influence of the cement plant was found to be low in comparison with other potential emission sources in the area, as no decrease in the immission concentrations was noted after the facility ceased its industrial activity. No significant differences were observed in human health risks derived from the exposure to metals and PCDD/Fs before and after the plant ceased the cement production. Risk values for the population living near the facility were similar to those found for residents living in a number of urban and suburban areas.

N-octanol-water partition coefficients (log K(OW)) of 399 congeners of polychlorinated azoxybenzenes (PCAOBs) determined by QSPR- and ANN-based approach

Polychlorinated azoxybenzenes (PCAOBs) theoretically consist of 798 congeners with 399 in cis and 399 in trans configuration. PCAOBs in trans configuration are largerly planar compounds and some are highly toxic and environmentally relevant compared to cis congeners. Trans-PCAOBs can be found as by-side products in 3,4-dichloroaniline and some herbicides. To fulfill gaps in physical and chemical properties of PCAOBs, the values of log K(OW) were determined for 399 congeners of t-CAOB using a computational approach. We used the semi-empirical RM1 in MOPAC and DFT B3LYP in Gaussian 03 methods, artificial neural net (ANN) predictions, and the standardized variables with and without the normal varimax rotation. The models created predicted the values of log K(OW) of all 399 chlorinated derivatives of trans-azoxybenzenes (C-t-AOBs). The values of log K(OW) of C-t-AOBs varied between 5.08 and 5.42 for Mono-, 5.16 and 5.96 for Di-, 5.79 and 6.73 for Tri-, 6.26 and 7.18 for Tetra-, 6.65 and 7.54 for Penta-, 7.13 and 7.94 for Hexa-, 7.20 and 8.20 for Hepta-, 7.96 and 8.32 for Octa-, 8.32 and 8.43 for Nonachloro-t-AOBs and 8.55 and 8.97 for Decachloro-t-AOB. These log K(OW) values were similar per chloro-t-AOB congener and independent of the calculation method. C-t-AOBs have log K(OW) values above 4.5, and what relates to contaminants of low or very low environmentally mobility but a high predilection to the soil and sediment particles and with potential for bioaccumulation. The models that used the standardized variables had smallest errors and higher correlation coefficients compared to the models that based on the normal varimax rotation of standardized structural descriptors. In light of these data, the semi-empirical RM1 calculations in MOPAC software and followed by ANN were a much less time consuming and less expensive compared to the DFT B3LYP method.

Monitoring temporal trends in environmental levels of polychlorinated dibenzo-p-dioxins and dibenzofurans: results from a 10-year surveillance program of a hazardous waste incinerator

The only hazardous waste incinerator (HWI) in Spain has been operating in Constantí (Tarragona County, Catalonia) since 1999. Before its construction, a surveillance program was initiated to monitor the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the neighborhood of the facility. In 2008, 40 soil and 40 vegetation samples were collected and PCDD/F levels determined. The median PCDD/F concentration in soil was 0.49 ng international toxic equivalents (I-TEQ)/kg. Although it meant a nonsignificant decrease of 44% with respect to the preoperational survey, important fluctuations of the levels of PCDD/Fs through time were found in some specific sites. Therefore, a new survey was performed 1 year later (2009) by deleting those sampling sites with inconstant values, which mostly coincided with urban zones. In 2009, the median level of PCDD/Fs in soils was found to be 0.42 ng I-TEQ/kg. In contrast, median PCDD/F levels in vegetation were 1.11 ng I-TEQ/kg, a significant increase compared with previous surveys (range of the median 0.21-0.25 ng I-TEQ/kg). However, this increase was uniformly observed in the entire sampling area, suggesting that lack of rainfall was a key parameter for decreasing plant dilution and wash-up of pollutants on vegetation. This indicates that in surveillance programs, information must be obtained from different sources because the use of a single compartment may yield significant misinterpretation when evaluating temporal trends of environmental pollutants. Human health risks derived from exposure to PCDD/Fs were also assessed for the local population. The results indicated that current concentrations of these contaminants do not pose any additional carcinogenic or noncarcinogenic risk for those people living near the HWI.

Partial replacement of fossil fuel in a cement plant: risk assessment for the population living in the neighborhood

In cement plants, the substitution of traditional fossil fuels not only allows a reduction of CO(2), but it also means to check-out residual materials, such as sewage sludge or municipal solid wastes (MSW), which should otherwise be disposed somehow/somewhere. In recent months, a cement plant placed in Alcanar (Catalonia, Spain) has been conducting tests to replace fossil fuel by refuse-derived fuel (RDF) from MSW. In July 2009, an operational test was progressively initiated by reaching a maximum of partial substitution of 20% of the required energy. In order to study the influence of the new process, environmental monitoring surveys were performed before and after the RDF implementation. Metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in soil, herbage, and air samples collected around the facility. In soils, significant decreases of PCDD/F levels, as well as in some metal concentrations were found, while no significant increases in the concentrations of these pollutants were observed. In turn, PM(10) levels remained constant, with a value of 16μgm(-3). In both surveys, the carcinogenic and non-carcinogenic risks derived from exposure to metals and PCDD/Fs for the population living in the vicinity of the facility were within the ranges considered as acceptable according to national and international standards. This means that RDF may be a successful choice in front of classical fossil fuels, being in accordance with the new EU environmental policies, which entail the reduction of CO(2) emissions and the energetic valorization of MSW. However, further long-term environmental studies are necessary to corroborate the harmlessness of RDF, in terms of human health risks.

Environmental monitoring of metals, PCDD/Fs and PCBs as a complementary tool of biological surveillance to assess human health risks

The results of an environmental program around the municipal solid waste incinerator (MSWI) of Mataró (Catalonia, Spain), which was designed to assess the potential impact of the facility on the close environment and the health of the population living in the vicinity, are here reported. Metals, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were analyzed in soil and air samples collected in/around the facility. In soils, Mn and Zn showed the highest metal concentrations (ranges: 136-648 mg kg(-1) and 29.6-97.8 mg kg(-1), respectively), while total concentrations of PCDD/Fs and PCBs were 0.14-0.46 ng WHO-TEQ kg(-1) and 167-3340 ng kg(-1), respectively. In air, the highest metal levels corresponded to Cu (range: 26.9-52.9 ng m(-3)) and Mn (range: 6.92-19.3 ng m(-3)), while those of PCDD/Fs and PCBs ranged 0.008-0.015 pg WHO-TEQ m(-3) and 9.20-42.1 pg m(-3), respectively. Carcinogenic and non-carcinogenic risks derived of exposure to metals, PCDD/Fs and PCBs did not exceed the threshold values. Complementarily analyzed with the results obtained in the concurrent biomonitoring study and the stack emissions, data indicate that the MSWI of Mataró does not mean significant human health risks derived of emissions of metals, PCDD/Fs and PCBs.

Application of self-organizing maps for PCDD/F pattern recognition of environmental and biological samples to evaluate the impact of a hazardous waste incinerator

Kohonen's self-organizing maps (SOM) is one of the most popular artificial neural network models. In this study, SOM were used to assess the potential relationships between polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) congener profiles in environmental (soil, herbage, and ambient air) and biological (plasma, adipose tissue, and breast milk) samples, and the emissions of a hazardous waste incinerator (HWI) in Spain. The visual examination of PCDD/F congener profiles of most environmental and biological samples did not allow finding out any differences between monitors. However, the global SOM analysis of environmental and biological samples showed that the weight of the PCDD/F stack emissions of the HWI on the environmental burden and on the exposure of the individuals living in the surroundings was not significant in relation to the background levels. The results confirmed the small influence of the HWI emissions of PCDD/Fs on the environment and the population living in the neighborhood.