Evaluation of a new automated cleanup system for the analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans in environmental samples

A novel approach to the extraction and analysis of dioxins and furans sampled onto Amberlite XAD-2 sorbent

Despite the efficacy of strong emission control plans that have been implemented the last few decades, polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) may still be released from anthropogenic sources such as sinter plants, and municipal and hazardous waste incinerators. Monitoring for PCDDs and PCDFs in gaseous emissions from such facilities is important due to the acute toxicity of these compounds even at trace levels. Currently, most of these samples from the African continent are being analysed abroad at high cost, with the direct consequence that the number of measurements are kept to a minimum. In this context, we developed a more affordable analytical approach for the measurement of PCDD/Fs sampled onto Amberlite XAD-2 sorbent, which relies on a novel extraction, clean-up, and analysis method with the aim of reducing both the cost and the complexity of standard methods while maintaining high quality results. A simple, sequential, 3 hour end-over-end tumbling extraction procedure was developed employing acetone : n-hexane (1 : 9) as extraction solvent. This was combined with a dimethyl sulfoxide (DMSO) clean-up to remove aliphatic interferences, prior to direct analysis by gas chromatography triple quadrupole mass spectrometry. The Unites States Environmental Protection Agency Method 23, in contrast, requires a 16 hour Soxhlet extraction with toluene and multiple column chromatography steps. The end-over-end tumbling extraction yielded an average recovery of 79% for PCDD/Fs usually monitored in gaseous samples, whilst an average recovery of 89% was achieved for the DMSO clean-up procedure. In addition, an overall average recovery of 78% and a Z-score of -1.1 was obtained using the developed method for the proficiency testing of a solid reference material, proving the method is fit for purpose. It was then successfully applied to the analysis of air emissions from a medical waste incinerator, which further showed that the alternative approach may deliver quality, fast, and cost-effective analysis of gaseous PCDD/Fs sampled onto Amberlite XAD-2 sorbent in a developing country context.

Qualitative and quantitative changes in traffic and waste incineration PCDD/Fs in urban air and soils under different seasonal conditions (Metropolitan Area of Barcelona)

A sampling and analysis scheme was implemented to discriminate between inputs of polychlorodibenzo-p-dioxins and polychlorodibenzofurans (PCDD/Fs) at low concentrations in urban areas. Ambient air and soils were sampled and analyzed in five stations in the Metropolitan area of Barcelona (2018-2019); one located in a reference urban traffic site and four in the area of influence of an integrated waste management facility (IWMF) that included a solid waste incinerator. Seasonality was the main factor determining the PCDD/F composition, and involved lower values in the warmer months. This seasonal effect was related to enhanced photooxidation of PCDDs compared to PCDFs and faster depletion of the less chlorinated congeners due to volatility at higher ambient temperature; consistent with the compounds' octanol-air partition coefficients. The ratio 2,3,7,8-tetrachlorobenzofuran/1,2,3,4,6,7,8-heptachlorobenzofuran allowed, for the first time, identifying cases of preferential contributions of IWMF and traffic inputs, i.e. values of 0.06 and 0.32, respectively. Combination of this ratio with the airborne PCDD/F levels illustrated that the quantitative PCDD/F levels were not a useful criterion for elucidation between IWMF and traffic inputs. PCDD/Fs levels in soils ranged between 9.0 and 22 pg WHO-TEQ/g in the two sites closest to the IWMF, while the other sites, including the traffic site, showed values between 0.8 and 1.9 pg WHO-TEQ/g. The levels in the former group were higher than those observed in other urban areas and above 5 pg WHO-TEQ/g, which is a limit reference value in several European countries. The C₇ and C₈ observed congener distributions in all soils examined were different from those in the air samples and similar to those reported in sewage sludge from waste water treatment plants, not showing influences from IWMF or traffic PCDD/F inputs.

Mechanisms of pH-Dependent Uptake of Ionizable Organic Chemicals by Fish from Oil Sands Process-Affected Water (OSPW)

Uptake and effects of ionizable organic chemicals (IOCs) that are weak acids in aqueous solution by fish can differ as a function of pH. While the pH-dependent behavior of select IOCs is well-understood, complex mixtures of IOCs, e.g., from oil sands process-affected water (OSPW), have not yet been studied systematically. Here, we established an in vitro screening method using the rainbow trout gill cell line, RTgill-W1, to investigate pH-dependent cytotoxicity and permeation of IOCs across cultured epithelia using ultra-high-performance liquid chromatography with high-resolution mass spectrometry (UPLC-HRMS). The assay was benchmarked using model chemicals and technical mixtures, and then used to characterize fractions and reconstituted extracts of field-collected OSPW. Significant pH-dependent cytotoxicity of individual IOCs, acidic fractions, and reconstituted extracts of OSPW was observed. In vitro data were in good agreement with data from a 96 h in vivo exposure experiment with juvenile rainbow trout. Permeation of some IOCs from OSPW was mediated by active transport, as revealed by studies in which inhibitors of these active transport mechanisms were applied. We conclude that the RTgill-W1 in vitro assay is useful for the screening of pH-dependent uptake of IOCs in fish, and has applications for in vitro-in vivo extrapolation, and prioritization of chemicals in nontarget screenings.

Long-term monitoring programme of polychlorinated dioxins and polychlorinated furans in ambient air of Catalonia, Spain (1994-2015)

Reductions in concentrations of persistent organic pollutants were observed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in a comparison of two consecutive decades ending in December 31, 2015 (n = 413) and compiled from a 48-station long-term air-monitoring network in Catalonia, Spain. Reductions were observed in geometric mean concentration of total PCDD/Fs, decreasing at a rate of 11% yr^-1. Results reflect the relative success of improved pollution control measures at industry and traffic locations. At traffic and industrial locations, PCDD/Fs were reduced by around 68% (from 70 to 22 fg I-TEQ/m³) and 66% (from 57 to 19 fg I-TEQ/m³), respectively. The highest concentration of 1196 fg I-TEQ/m³ was observed during the first decade at an industrial location. The highest concentration over the second decade was at a background location during winter (674 fg I-TEQ/m³). Winter observations are generally higher than those recorded in summer, as evident in an 8-year period of moderate PCDD/F levels (<250 fg I-TEQ/m³, n = 143). PCDD/F congener profiles were identified has having less chlorinated PCDD/F, indicating the presence of nearby combustion sources at selected locations. More long-term sampling campaigns, combined with network optimization and integration into a meteorological model, can offer a tool for future PCDD/Fs control measures in not only Catalonia - but also applicable to other areas.

Changes in serum dioxin and PCB levels in residents around a municipal waste incinerator in Bilbao, Spain

There is a great concern in the Basque Country regarding emissions from waste incineration, in particular that of organochlorines (OCs), including dioxins, furans and polychlorinated biphenyls (PCBs), and their potential effect on human health. In 2005, a municipal solid waste plant (MSWP) started to operate in Bilbao, representing an opportunity to assess the exposure to the aforementioned pollutants among people living at various distances from the plant. In 2006 and 2008, we carried out two cross-sectional studies to quantify and assess changes in levels of these pollutants. The objective of this study was to describe the levels of OCs in the blood serum in 2013 of 127 adults of this prospective cohort, in four centres of population, near to and further away from the MSWP, and to study trends over time since it started to operate. This study shows the levels of OCs have decreased significantly, from 37.2% to 80.1%. Further, levels of OCs in areas near to the MSWP were not found to be higher than those in areas further afield.

Dioxins and dl-PCBs in gull eggs from Spanish Natural Parks (2010-2013)

The aim of this study was to evaluate the presence and distribution of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs), concretely those so-called as dioxin-like PCBs, in yellow-legged gull eggs (Larus michahellis) collected from five Natural Parks (some of them National Parks) in Spain during the period 2010-2013. PCDD/Fs and dl-PCBs were detected in all the samples. Due to the proximity to important urban and industrial areas higher concentrations were determined in colonies located in the Northern Mediterranean coast than those found in the Southern Mediterranean or Atlantic colonies where a softer anthropogenic impact occurs. Mean ∑PCDD/F concentrations ranged from 49 to 223pg/g lipid weight (lw) and ∑dl-PCB concentrations varied from 146 to 911ng/g lw. In the Natural Park of the Ebro Delta (Northern Mediterranean coast) two gull species share habitat: yellow-legged and Audouin gull (Larus audouinii). Eggs from both species were collected and PCDD/F and dl-PCB levels compared. The species that feeds exclusively on pelagic fish (L. audouinii) had significantly higher PCDD/F and dl-PCB levels than the scavenger L. michahellis, pointing out the diet-dependent differences in the accumulation of persistent organic pollutants between similar cohabitant breeding species. Finally, mean TEQ values were in general below those considered as critical for toxicological effects in birds.

Triple quadrupole tandem mass spectrometry: A real alternative to high resolution magnetic sector instrument for the analysis of polychlorinated dibenzo-p-dioxins, furans and dioxin-like polychlorinated biphenyls

This paper reports on the optimisation, characterisation, validation and applicability of gas chromatography coupled to triple quadrupole mass spectrometry in its tandem operation mode (GC-QqQ(MS/MS) for the quantification of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs, dioxins) and dioxin-like polychlorinated biphenyls (DL-PCBs) in environmental and food matrices. MS/MS parameters were selected to achieve the high sensitivity and selectivity required for the analysis of this type of compounds and samples. Good repeatability for areas (RSD = 1-10%, for PCDD/Fs and DL-PCBs) and for ion transition ratios (RSD = 0.3-10%, for PCDD/Fs, and 0.2-15%, for DL-PCBs) and low instrumental limits of detection, 0.07-0.75 pg μL(-1) (for dioxins) and 0.05-0.63 pg μL(-1) (for DL-PCBs), were obtained. A comparative study of the congener specific determination using both GC-QqQ(MS/MS) and gas chromatography-high resolution mass spectrometry (GC-HRMS) was also performed by analysing several fortified samples and certified reference materials (CRMs) with low (feed and foodstuffs), median (sewage sludge) and high (fly ash) toxic equivalency (TEQ) concentration levels, i.e. 0.60, 1.83, 72.9 and 3609 pg WHO-TEQ(PCDD/Fs) g(-1). The agreement between the results obtained for the total TEQs (dioxins) on GC-QqQ(MS/MS) and GC-HRMS in all the investigated samples were within the range of ±4%, and that of DL-PCBs at concentration levels of 0.84 pg WHO-TEQs (DL-PCBs) g(-1), in the case of feedstuffs, was 0.11%. Both instrumental methods have similar and comparable linearity, precision and accuracy. The GC-QqQ(MS/MS) sensitivity, lower than that of GC-HRMS, is good enough (iLODs in the down to low pg levels) to detect the normal concentrations of these compounds in food and environmental samples. These results make GC-QqQ(MS/MS) suitable for the quantitative analysis of dioxins and DL-PCBs and a real alternative tool to the reference sector HRMS instruments.

High-throughput method of dioxin analysis in aqueous samples using consecutive solid phase extraction steps with the new C18 Ultraflow™ pressurized liquid extraction and automated clean-up

A high-throughput analytical method has been developed for the determination of seventeen 2,3,7,8-substituted congeners of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in aqueous samples. A recently introduced octadecyl (C18) disk for semi-automated solid-phase extraction of PCDD/Fs in water samples with a high level of particulate material has been tested for the analysis of dioxins. A new type of C18 disk specially designed for the analysis of hexane extractable material (HEM), but never previously reported for use in PCDD/Fs analysis. This kind of disk allows a higher filtration flow, and therefore the time of analysis is reduced. The solid-phase extraction technique is used to change samples from liquid to solid, and therefore pressurized liquid extraction (PLE) can be used in the pre-treatment. In order to achieve efficient purification, extracts from the PLE are purified using an automated Power-prep system with disposable silica, alumina, and carbon columns. Quantitative analyses of PCDD/Fs were performed by GC-HRMS using multi-ion detection (MID) mode. The method was successfully applied to the analysis of water samples from the wastewater treatment system of a vinyl chloride monomer plant. The entire procedure is in agreement with EPA1613 recommendations regarding the blank control, MDLs (method detection limits), accuracy, and precision. The high-throughput method not only meets the requirements of international standards, but also shortens the required analysis time from 2 weeks to 3d.

Background concentrations of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in the global oceanic atmosphere

The remote oceans are among the most pristine environments in the world, away from sources of anthropogenic persistent organic pollutants (POP), but nevertheless recipients of atmospheric deposition of POPs that have undergone long-range atmospheric transport (LRAT). In this work, the background occurrence of gas and aerosol phase polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin like polychlorinated biphenyls (dl-PCB) is evaluated for the first time in the atmosphere of the tropical and subtropical Atlantic, Pacific, and Indian oceans. Thirty-nine air samples were collected during the eight-month Malaspina circumnavigation cruise onboard the R/V Hespérides. The background levels of dioxins and dl-PCBs remained very low and in many cases very close to or below the limit of detection. Expectedly, the levels of PCBs were higher than dioxins, PCB#118 being the most abundant compound. In the particular case of dioxins, octachlorodibenzo-p-dioxin (OCDD) was the most abundant PCDD/F congener. Distribution of dl-PCB is dominated by the gas phase, while for PCDD/F the aerosol phase concentrations were higher, particularly for the more hydrophobic congeners. The Atlantic Ocean presented on average the highest PCDD/F and dl-PCB concentrations, being lower in the southern hemisphere. The assessment of air mass back trajectories show a clear influence of continental source regions, and lower concentrations when the air mass has an oceanic origin. In addition, the samples affected by an oceanic air mass are characterized by a lower contribution of the less chlorinated dioxins in comparison with the furans, consistent with the reported higher reaction rate constants of dibenzo-p-dioxins with OH radicals than those of dibenzofurans. The total dry atmospheric deposition of aerosol-bound ∑PCDD/F and ∑dl-PCB to the global oceans was estimated to be 354 and 896 kg/year, respectively.

Biological monitoring of PCDD/Fs and PCBs in the City of Mataró. A population-based cohort study (1995-2012)

There is great concern about the exposure to PCDD/Fs in areas near solid waste incineration (SWI) plants as, in the past, thermal waste treatment was a major source of PCDD/Fs, affecting negatively the environment and the population living nearby the area of influence. The aim of the present study was to monitor PCDD/Fs and PCBs levels in blood samples in general population living nearby a modern SWI. Up to 7 different campaigns were performed between 1995 and 2012. Overall, 104 exposed subjects (living <1000 m from the incinerator plant) and 97 non-exposed subjects (living >3000 m from the incinerator plant) were randomly selected from the municipal census of the City of Mataró in 1995. In addition, workers of the SWI plant were included in the study. Moreover, in 1999, 100 non-exposed subjects living in the nearby City of Arenys de Mar were added to the project. Overall, this study represents the longest consecutive human biomonitoring study of dioxins, furans and PCBs ever conducted in Spain. Concentrations of PCDD/Fs and PCBs were determined according to age, sex and distance to the SWI exposure in whole blood sample pools. No relevant differences in PCDD/Fs and PCBs levels were observed between SWI exposure groups. It could be noted that since 1999 all groups experienced a slight decrease in the levels of PCDD/Fs and marker PCBs. Moreover, concentrations of PCDD/Fs and marker PCBs were higher in women than in men, and in older age group in comparison to the younger ones.

Levels of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in placentas from the Spanish INMA birth cohort study

Because fetuses are considered significantly more sensitive to various environment toxicants, there is a need for continuous biomonitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls PCBs (DL-PCBs) to assess their impact on this susceptible population. The aim of this study was to assess the concentration of PCDD/Fs and DL-PCBs in placenta samples from women participating in the Spanish Environment and Childhood (INMA) birth cohort study and to evaluate whether maternal and child characteristics predict placenta concentrations of these pollutants. The presence of PCDD/Fs and DL-PCBs was investigated in 50 placenta samples selected at random in the recruitment period 2000-2008. Multivariable regression models were constructed. Mothers had a mean age at delivery of 30.7 years (18.0-38.0 years), pre-pregnancy BMI of 23.3 kg/m² (18.0-40.2 kg/m²), and 31% were smokers. Median total concentrations of PCDD/Fs and DL-PCBs were 6.9 pg WHO-TEQ/g lipid and 2.1 pg WHO-TEQ/g lipid, respectively. In comparison to the few previous studies in placenta, total TEQ levels were among the lowest recorded in comparable general populations. The congener distribution pattern and the frequencies and concentrations of PCDD/F and DL-PCB congeners were similar to previous reports in placenta. PCDD/F and DL-PCB exposure was related to the age of the mother and the year of the delivery. Although placental concentrations cannot be considered wholly appropriate predictors for evaluating fetal exposure to these contaminants, they can provide a good indication of both maternal and infant prenatal and postnatal exposure and can be used as a proxy for fetal exposure.

Development of the automated cleanup system for the analysis of PCDDs, PCDFs and DL-PCBs

A new automated cleanup system for the analysis of dioxins (PCDDs, PCDFs and DL-PCBs) has been developed. It was controlled by PLC through the touch-panel. This automated cleanup system can simultaneously treat six samples in 2h, using only about 30 mL of solvent. In this study, the recovery rates of the internal standard added as cleanup spiked were between 70% and 120% in the fly ash sample. The RSDs (relative standard deviations) were below 15%. The shortest analysis time from cleanup to calculation of concentration was approximately 6h. Moreover, this automated cleanup system eliminates personal error in sample preparation and training time for the analyst, and improves the accuracy of the experiment. Additionally, this automated cleanup system allowed rapid analysis and less consumption of organic solvent.

Development of a new automated clean-up system for the simultaneous analysis of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and 'dioxin-like' polychlorinated biphenyls (dl-PCB) in flue gas emissions by GPC-SPE

A comprehensive clean-up method for quantitative analysis of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzo-furans (PCDD/Fs) in one single extract of environmental samples was developed. Since the chemical nature and toxicity of planar PCBs are similar to those of PCDD/Fs, dioxin-like PCBs and PCDD/Fs are often surveyed together in their exposure assessments. The development of a method for the simultaneous analysis of PCBs and PCDD/Fs in environmental samples is invaluable. The automated clean-up system evaluated in this work consists of three additional steps after traditional extraction: the chromatography on gel permeation (GPC), the concentration of the solvent through the use of an in-line evaporation module and the further purification and separation of PCDDs/Fs and dl-PCBs on an alumina cartridge in the 'SPE module'. In this work, three fly ash samples from an interlaboratory study with different PCDD/F and PCB levels were Soxhlet-extracted and then cleaned up using an automated system. PCDD/Fs and PCBs were determined using isotope dilution and high resolution gas chromatography/high resolution mass spectrometry. The determined values of 17 PCDD/Fs were consistent with the certified values and the relative standard deviations (RSDs) of the determined values were less than 20%. The recoveries of (13)C labeled PCDD/Fs and planar PCBs, and their RSDs were within the ranges specified in EPA1613 and 1668a methods, respectively. An accurate and reliable method was successfully developed and can be used in the simultaneous analysis of PCDD/Fs and planar PCBs in environmental samples.

PCDD/F formation from oxy-PAH precursors in waste incinerator flyash

The yield of PCDD/F in relation to the presence of oxygenated PAH in model waste incinerator flyash has been investigated in a fixed bed laboratory scale reactor. Experiments were undertaken by thermal treatment of the model flyash at 250 and 350°C under a simulated flue gas stream for 2 h. After reaction, the PCDD/F content of the reacted flyash and the PCDD/F released into the exhaust gas, and subsequently trapped by XAD-II resin in a down-stream condensation system were analyzed. The PAHs investigated were, dibenzofuran and benzo[b]naphtho[2,3-d]furan and were spiked onto the model flyash as reactant precursors for PCDD/F formation. The results showed significant formation of furans from both of the PAH investigated, however except from some highly chlorinated dioxin congeners, the formation of dioxins was not so common. Benzonaphthofuran was significantly more reactive than dibenzofuran in PCDD/F formation, in spite of the fact that dibenzofuran is structurally more similar to that of PCDD/F. Thus, there was no clear attribution between the chemical structure of PAH used and the formation of PCDD/F. There were considerable differences between the yields of PCDD/F congeners in the gaseous species and those in the reacted flyash under the same operational conditions. The concentration of PCDD/Fs was reduced at the higher reaction temperature of 350°C; however, the higher temperature resulted in the majority of the PCDD/F formed on the flyash being released into the gas phase.

Removal potential of toxic 2378-substituted PCDD/F from incinerator flue gases by waste-derived activated carbons

The application of activated carbons has become a commonly used emission control protocol for the removal or adsorption of persistent organic pollutants from the flue gas streams of waste incinerators. In this study, the 2378-substituted PCDD/F removal efficiency of three types of activated carbons derived from the pyrolysis of refuse derived fuel, textile waste and scrap tyre was investigated and compared with that of a commercial carbon. Experiments were carried out in a laboratory scale fixed-bed reactor under a simulated flue gas at 275°C with a reaction period of four days. The PCDD/F in the solid matrices and exhaust gas, were analyzed using gas chromatography coupled with a triple quadrupole mass spectrometer. In the absence of activated carbon adsorbent, there was a significant increase in the concentration of toxic PCDD/F produced in the reacted flyash, reaching up to 6.6 times higher than in the raw flyash. In addition, there was a substantial release of PCDD/F into the gas phase, which was found in the flue gas trapping system. By application of the different commercial, refuse derived fuel, textile and tyre activated carbons the total PCDD/F toxic equivalent removal efficiencies in the exhaust gas stream were 58%, 57%, 64% and 52%, respectively. In general, the removal of the PCDDs was much higher with an average of 85% compared to PCDFs at 41%. Analysis of the reacted activated carbons showed that there was some formation of PCDD/F, for instance, a total of 60.6 μg I-TEQ kg(-1) toxic PCDD/F was formed in the refuse derived fuel activated carbon compared to 34 μg I-TEQ kg(-1) in the commercial activated carbon. The activated carbons derived from the pyrolysis of waste, therefore, showed good potential as a control material for PCDD/F emissions in waste incinerator flue gases.

PCDD/F and DL-PCB levels in meat from broilers and rabbits fed with fish-oil enriched feeds

The aim of this study was to assess the effect on the final levels of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in meat when fats, in particular fish oils, are included as ingredients in feeds. Two types of animals (broilers and rabbits) were fed with three different experimental feeds containing varying amounts of two selected fish oils. PCDD/Fs and DL-PCBs were determined in the fish oils, the feeds and in the animals' meat. For broilers, PCDD/F and DL-PCB profiles in meat samples were similar to those found in the corresponding feeds, even though bioaccumulation of the highest chlorinated PCDD/F congeners seemed to decrease. Depending on the treatment, PCDD/F and the sum of PCDD/F and DL-PCB levels were 1.11-4.60 and 6.03-16.71 pg WHO-TEQ/g fat, respectively. For most of the cases, these values exceeded the maximum established by the Commission Regulation (EC) No. 1881/2006. In contrast, the levels of these contaminants in the corresponding feeds ranged from 0.11 to 0.54 pg WHO-TEQ/g, in the case of PCDD/Fs, and from 0.59 to 1.75 pg WHO-TEQ/g, when DL-PCBs were also included. These levels were, in general, below the maximum allowed by the Commission Directive 2006/13/EC. The results of the experiments with rabbits were not as conclusive as those for broilers although bioaccumulation appeared to be slower.

Water-quality monitoring technique for dioxins during dredging using on-site solid phase extraction with graphitic carbon and analysis with DR-CALUX

In Japan, water-quality monitoring with the environmental dioxin standard of 1 pg-TEQ/L at basic monitoring points set in a border between operation-area water and normal water is necessary for removal operations for bottom sediments containing dioxins. This paper presents a technique for combining on-site graphitic carbon (GrC) solid-phase extraction and bioassay method for the simplification and facilitation of water-quality monitoring. Using this method, we conducted experiments at an actual sediment removal site. Comparative analyses using high-resolution GC/MS (HRGC-HRMS) between the dioxin concentrations detected using a GrC solid-phase extraction kit and the official analytical method yielded similar concentrations and distributions of isomers for detected PCDD/Fs and DL-PCBs. The GrC solid-phase extraction method is inferred to have capacity equal to official analytical method extraction. Toxicity equivalent concentrations estimated using DR-CALUX correlate with equivalent concentrations with HRGC/HRMS. No false positive or false negative result was obtained for the standard value 1 pg-TEQ/L.

Analysis of Polychlorinated Dibenzo-p-Dioxins and Polychlorinated Dibenzofurans in Soil and Sediment

This review presents methods for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), called dioxins, in soil and sediment. These compounds are produced as by-products of different combustion processes, and because of their persistency and toxicity they present a threat for animal and human health. Due to their high organic matter content, soil and sediment can accumulate dioxins and have become important secondary emission sources. Determining dioxins in these samples is complex because dioxins are present in trace levels and have to be separated from interferences whereas other classes of organic contaminants are present in higher concentrations. After sampling, follows extraction of compounds with a suitable solvent, extract clean-up from unwanted compounds, and qualitative and quantitative analysis. At the end of this review, we gave levels of PCDD/PCDFs found in soil and sediment samples.

Polychlorinated biphenyls (PCBs) in the atmosphere of sub-alpine northern Italy

The main objective of this work was to assess the atmospheric concentrations and seasonal variations of selected POPs in a sub-alpine location where few data are available. A monitoring and research station was set up at the JRC Ispra EMEP site (Italy). We present and discuss a one-year data set (2005-2006) on PCB air concentrations. Sigma 7PCBs monthly averaged concentration varied from 31 to 76 pgm(-3). Concentrations in the gas phase (21-72 pgm(-3)) were higher than those in the particulate phase (3-10 pgm(-3)). Advection of air masses and re-volatilization from local sources seem to play a dominant role as drivers of PCB atmospheric concentrations in the area. Indications of seasonal variation affecting PCB congener patterns and the gas/particulate partitioning were found. Modeling calculations suggest a predominant importance of the wet deposition in this region (1 microgm(-2)yr(-1) Sigma 7PCBs yearly total wet deposition flux; 650-2400 pgL(-1) rainwater concentrations).

PCDD/F and PCB multi-media ambient concentrations, congener patterns and occurrence in a Mediterranean coastal lagoon (Etang de Thau, France)

Ambient concentrations, congener patterns and multi-media distribution of PCDD/Fs and PCBs were determined in air, water, sediment and mussels in a semi-enclosed marine ecosystem (Thau lagoon, France). Sigma2,3,7,8-PCDD/F and sigma7ICES PCB air concentrations (0.2-1.4 and 31-57 pg m(-3), respectively) were typical of rural areas. Concentrations in the water column were very low for PCDD/Fs (163-476 fg L(-1)) and low for PCBs (138-708 pg L(-1)). PCDD/F and PCB concentrations found in surface sediment (0.15-1.6 and 2.5-33 ng g(-1) d.w., respectively) and mussel (13-21 pg g(-1) d.w. and 10-39 ng g(-1) d.w., respectively) were medium levels. PCDD/F congener patterns observed in air, water particulate phase and sediments were similar suggesting direct coupling among these compartments and atmospheric inputs of PCDD/Fs into the lagoon. Conversely, for the same set of samples, similar patterns were not observed for PCBs in the mentioned compartments.

Levels of PCDD/Fs and trace elements in superficial soils of Pavia Province (Italy)

Trace elements and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in soils from rural and light-industrialized sites (n = 168) of Province of Pavia (Northern Italy). Most of the trace element values fit in typical ranges of concentrations in soils and are similar to the ones reported for rural sites in Italy or sites with no direct anthropogenic impact. Total concentrations of 2,3,7,8 chlorine substituted PCDD/Fs in superficial soils ranged between 24.4 and 1287 pg g(-1) dw (0.5-28.9 pg WHO98-TEQ g(-1) dw). The North Eastern part of the Province presented significantly higher levels (p < 0.001) than the rest of the Province for As, Cd, Hg, Pb, Zn and PCDD/Fs. While the existence of a defined heavy metal polluting source for this specific site has been suggested, in the case of PCDD/Fs, profiles were not linked to any specific emission source fingerprint. In the whole extension of Pavia Province, OCDD/F dominated the 2,3,7,8 chlorine substituted congener soil pattern, followed by the 1,2,3,4,6,7,8 hepta-CDD/F congener. Principal Component Analysis (PCA) showed that this profile could not be associated to any described PCDD/F emission source fingerprint and was relatively similar to the baseline deposition of sites with no direct impact of PCDD/F emission sources independently of land use.

Baseline levels of dioxin and furan emissions from waste thermal treatment in Colombia

Background data of polychlorinated dibenzodioxin and dibenzofuran (PCDD/Fs) emissions from the incineration sector in Colombia are presented. Monitoring was carried out during a two-year period, 2003-2005. Twelve plants were sampled for stack gas emissions of dioxins and total solid particulate (TSP). Additionally, PCDD/Fs in several fly ash samples were analyzed. Most incinerators burned industrial refuse materials and medical residues. A wide range of PCDD/Fs emission levels were found. In particular, levels ranging from 6.9 to 343.8 ng I-TEQ/N m(3) were determined in plants without any air pollution control system (APCS). In contrast, 0.5-39.2 ng I-TEQ/N m(3) levels were found in plants with APCS while 8.5-67.5 ng I-TEQ/g were measured in fly ash samples. TSP values ranged from 14 to 448 mg/N m(3). This study also evaluated the impact of implementing different control systems in an incinerator. Finally, for comparison purposes several samples were analyzed by both high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC-HRMS) and high resolution gas chromatography coupled to ion-trap low resolution mass spectrometry-mass spectrometry (HRGC-IT LRMS/MS). Overall, I-TEQ values deviated about 20-30% between both techniques.

Atmospheric input of POPs into Lake Maggiore (Northern Italy): PCDD/F and dioxin-like PCB profiles and fluxes in the atmosphere and aquatic system

The delivery and accumulation of PCDD/Fs and dioxin-like PCBs (DL-PCBs) as recorded in sediments from the Lake Maggiore (LM) in Northern Italy and the influence of the atmosphere in contaminating this subalpine ecosystem were studied. PCDD/Fs (17 congeners) and DL-PCBs (12 congeners) concentrations, congener profiles and fluxes in air, bulk deposition, aquatic settling material and surface sediments are presented. Our strategy was to obtain surface sediment from areas near riverine inputs and in the depositional basins, settling material in sediment traps at one site and air, aerosol and bulk deposition profiles. PCDD/F concentrations in air of 25 WHO-TEQ fg m(-3) and DL-PCBs of 7 WHO-TEQ fg m(-3) were measured. Bulk atmospheric deposition yielded 140 and 28 WHO-TEQ pg m(-2) per week for dioxins/furans and DL-PCBs, respectively. Aquatic settling material exhibited concentrations of 11 WHO-TEQ pg g(-1) for PCDD/Fs and 2 WHO-TEQ pg g(-1) for DL-PCBs. Weekly settling material fluxes of 50 WHO-TEQ pg m(-2) and 10 WHO-TEQ pg m(-2) were obtained for PCDD/Fs and DL-PCBs, respectively. PCDD/Fs concentrations in surface sediments varied from 0.1 to 17 WHO-TEQ pg g(-1) whereas values ranged from 0.03 to 6 WHO-TEQ pg g(-1) for DL-PCBs. The concentrations obtained in the environmental compartments studied suggest a situation of low level contamination. PCDD/Fs and DL-PCBs congener profiles in atmospheric air, bulk deposition, aquatic settling matter and surface sediment point to an important if not dominant contribution from atmospheric deposition to Lake Maggiore, especially derived from wet deposition of aerosol-bound PCDD/Fs and DL-PCBs. Flux estimates support this hypothesis.

Atmospheric input of POPs into Lake Maggiore (Northern Italy): PBDE concentrations and profile in air, precipitation, settling material and sediments

Large lakes are sinks for many chemical pollutants but the role of the atmosphere in delivering PBDEs (polybrominated diphenyl ethers) is not well known. In this study we estimated inputs of PBDEs from the atmosphere to Lake Maggiore and the delivery via settling material to accumulated bottom sediments. Sampling consisted of one simultaneous week of air and bulk deposition during Spring 2005, an integrated 4-month period of collected settling material (via sediment trap), and superficial bottom sediments near the sediment trap deployment and tributary mouths of the lake. Concentration of total PBDEs (Sigma 8) in the sediments ranged between 0.06 and 27 ng g(-1), and two different patterns were observed. One pattern was dominated by BDE-47 and BDE-99 and a second by BDE-209. The latter pattern suggested input from local source(s). Total PBDEs in air were 107 pg m(-3) with a pattern dominated by BDE-47. The bulk deposition rate of total PBDEs for precipitation was measurated to be 17.6 ng m(-2) day(-1) where BDE-209 exhibited the highest concentration. For aquatic settling material the flux was 3.57 ng m(-2) day(-1) and was dominated by congeners BDE-47 and BDE-99. The bulk deposition and settling material fluxes were in the same range for the less brominated congeners, while for the hepta- and deca-brominated PBDEs the fluxes in the settling material were one order of magnitude lower. This suggests different sedimentation processes among congeners and/or the presence of local sources that influence the relative distribution in water column.

Occurrence and bioaccumulation study of PCDD and PCDF from mineral feed additives

Extraction of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was evaluated in sepiolite matrices. Soxhlet extraction using different extracting strategies and acid treatment were tested. Acid treatment or Soxhlet extraction using a mixture of toluene:ethanol as solvent allowed to reach the minimum requirements for recovery rates. However, Soxhlet extraction using a mixture cyclohexane:toluene as extracting solvent did not allow to comply with these minimum requirements. Significant differences were obtained in TEQ units when acid treatment was applied in comparison to Soxhlet extraction. This fact can be explained because the use of drastic acid conditions allows removing strongly adsorbed analytes which can be uniquely extracted after a total destruction of the crystalline. On the contrary, Soxhlet extraction was not able to destroy the structure of sepiolite and as a consequence the PCDDs/Fs remain adsorbed in the internal structure of the mineral. A bioaccumulation study was also conducted to evaluate the transference of PCDDs/Fs from the sepiolite into the animal when fed with feed containing sepiolite. Four groups of chickens were exposed through diet to a control feed, feed with 3% w/w sepiolite, spiked feed contaminated with PCDDs/Fs and feed containing contaminated kaolinitic clay. Livers of animals were analyzed throughout the exposure period. Results of this trial showed that the performance of broilers was not affected by the presence of dioxins at levels tested, and chickens did not show any abnormal behaviour. Dioxins intentionally added to the diet were significantly absorbed and accumulated in liver, whereas the PCDDs/Fs from sepiolite were not available for chickens since livers from broilers fed 3% sepiolite presented similar WHO-TEQ values than those from broilers fed control diet.

Decomposition of paper wastes in presence of ceramics and cement raw material

Paper recycling is an environmental important activity that is carried out in all the countries, but during the recycling process a paper waste is produced. Generally these wastes are placed in landfill sites but it is possible to profit it as secondary fuel and raw material in manufacture furnaces. In this work the combustion of the waste papers with cement and ceramic raw material has been studied with the objective to analyse the interaction of these substances with the emitted pollutants like PAHs and PCDD/Fs. The results of the study show that the presence of inorganic material produces an increment in the lighter PAH emission but chlorinated compounds are not affected. The PCDD/F emission level found in the combustion of this waste is quite low compared with other wastes subjected to similar conditions.

PCDD/Fs and DL-PCBs in feeding fats obtained as co-products or by-products derived from the food chain

Among the tasks included in the "Quality and safety of feeding fats obtained from co-products or by-products of the food chain" Project, supported by the European Union and included in the 6th Framework Program, a number of fats and oils collected as co- or by-products from the food chain were selected for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and 'dioxin-like' polychlorinated biphenyls (DL-PCBs). In the majority of the cases these samples are currently employed as feed ingredients. Nevertheless, additional fats, which are forbidden for feedstuff purposes were also considered in this study. In general terms, fats and oils were classified taking into account their nature and the processes applied to obtain these co- or by-products. PCDD/F and DL-PCB levels were evaluated in a first group of samples composed of fish oils, animal fats and lecithins. As expected, fats and oils with an animal origin presented higher concentrations, expressed in pg WHO-TEQ/g, compared to the levels found in vegetable samples like lecithins. The category of fish oils had the highest values for both PCDD/Fs and the sum of PCDD/Fs and DL-PCBs, with some samples showing levels above the maximum established at the present legislation related to the presence of PCDD/Fs and DL-PCBs in animal feed [Commission Directive 2006/13/EC of 3 February 2006 amending Annexes I and II to Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed as regards dioxins and dioxin-like PCBs. Official Journal of the European Communities L32, 44-53]. In a second group, fats and oils with a more complex composition obtained from different transformation processes or even mixtures of fats were considered; thus, acid oils from chemical refining, acid oils from physical refining, recycled cooking oils, oils extracted from exhausted bleaching earths, hydrogenated by-products, fatty acids calcium soaps and miscellaneous fats were analyzed. The data revealed a significant variability in PCDD/F and DL-PCB levels, expressed in pg WHO-TEQ/g, in these products. It has to be pointed out that the analyses of fats and oils belonging to these categories of products were sometimes difficult due to the complexity of the samples. In terms of legislation most of these samples cannot be easily included into one of the specific categories of substances intended for feedstuff purposes that are regulated in Commission Directive 2006/13/EC.

Analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in vegetable oil samples by gas chromatography–ion trap tandem mass spectrometry

Gas chromatography coupled to ion trap tandem mass spectrometry (CG-MS-MS) has been evaluated for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in vegetable oil samples containing different concentration levels (0.2-6 pg WHO-TEQ g(-1) for both PCDD/Fs and dl-PCBs) of the 29 toxic congeners of PCDD/F and dioxin-like PCBs. The effect of potential interfering compounds such as polychlorinated naphthalenes (PCNs), polychlorinated biphenyls (PCBs) and polychlorinated diphenylethers (PCDEs) on the quantification of mono-ortho PCBs has been investigated. In addition, the influence of the clean-up procedure on the final determination by CG-MS-MS was studied, showing that the quality of the results depends to a great extent on this analytical step. Quality parameters have been established and good precisions (CV: 3-19%) and low limits of detection for PCDD/Fs (0.04-0.20 pg g(-1) oil) and dl-PCBs (0.08-0.64 pg g(-1) oil) were obtained. The method was validated by a comparison of the CG-MS-MS results with those obtained by GC-HRMS.

Occurrence of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Lake Maggiore (Italy and Switzerland)

Samples of air (gas and particulate phases), bulk deposition, aquatic settling material and sediments were collected in Lake Maggiore (LM) in order to determine their content of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Air (gas and particulate phases) concentrations were 0.5 pg m(-3), 80 pg m(-3), 13 pg m(-3) and 106 pg m(-3) for SigmaPCDD/Fs, SigmaPCBs, Sigma dioxin-like PCBs (DL-PCBs) and SigmaPBDEs, respectively. Deposition fluxes ranged from 0.7 ng m(-2) d(-1) for SigmaPCDD/Fs to 32 ng m(-2) d(-1) for SigmaPCBs. Aquatic settling material presented concentrations of 0.4 ng g(-1) dry weight (dw) for SigmaPCDD/Fs, 13 ng g(-1) dw for SigmaPCB, 3.4 ng g(-1) dw for SigmaDL-PCBs and 5.7 ng g(-1) dw for SigmaPBDEs. Mean sediment concentrations were 0.4 ng g(-1) dw for SigmaPCDD/Fs, 11 ng g(-1) dw for SigmaPCB, 3 ng g(-1) dw for SigmaDL-PCBs and 5.1 ng g(-1) dw for SigmaPBDEs. Similar PCDD/F and DL-PCB congener patterns in all the environmental compartments of LM point to an important, if not dominant, contribution of atmospheric deposition as source of these pollutants into LM. In contrast, PBDE congener distribution was not similar in the different environmental compartments. BDE 47 dominated air and settling material, while BDE 209 was the predominant congener in the bulk atmospheric deposition. Moreover, sediments showed two distinct PBDE congener profiles. Lower PBDE concentrated sediments were dominated by congeners 47 and 99, while BDE 209 dominated in higher PBDE concentrated samples. This suggests the influence of local sources as well as atmospheric input of PBDEs into LM.

Comparison of a variety of gas chromatographic columns with different polarities for the separation of chlorinated dibenzo-p-dioxins and dibenzofurans by high-resolution mass spectrometry

The applicability of 13 different GC columns (Agilent HP-5MS, Restek Rtx-5MS, Rtx-Dioxin2, Supelco Equity 5, SP-2331, Varian VF-5MS, CP-Sil 8 CB LowBleed/MS, J&W Scientific DB-5, DB-225, DB-XLB, DB-5MS, Phenomenex ZB-5MS, and ZB-5UMS) for US Environmental Protection Agency (EPA) methods 1613b, 8290 and European Standard Method EN 1948 for measurement of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) has been evaluated for the separation of all International Toxic Equivalent Factor (I-TEF) isomers (tetra- through octachlorinated at 2,3,7,8 positions) from closely eluting isomers using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). The relative performance data are compared based on mass chromatograms using a "visualization approach", absolute retention times, 2,3,7,8-substituted, total dioxins and furans concentrations, as well as TEQ comparisons. None of the columns tested were able to separate all 17 I-TEFs from other co-eluted isomers. Our data indicate that all I-TEFs isomers can be fully differentiated from closely eluting isomers using either of two sets of non-polar and polar stationary phase combinations. One set consists of DB-5 (HP-5MS, Rtx-5MS, Equity-5) and DB-225 GC columns and another set would have a combination of DB-5MS (ZB-5MS, VF-5MS, CP-Sil 8 CB LowBleed/MS) with SP-2331. However, depending on the source of PCDDs/PCDFs a laboratory could choose a single GC column that separates the 2,3,7,8-substituted congeners that contribute most significantly to the overall TEQ. These data are the most comprehensive to date, provide a valuable addition to operational criteria for the standard EPA methods 1613b, 8290, European Standard Method EN 1948 and will allow researches to compare data generated according to the different compliance analytical procedures.

Dioxin emissions from thermal waste management in Medellín, Colombia: present regulation status and preliminary results

Preliminary results of a study undertaken to characterize dioxin and furan releases from waste incineration plants operating in Medellín-Colombia are presented. Emission and fly ash samples were collected from representative plants burning medical and industrial residues to characterize PCDD/PCDF levels. Analyses were carried out following European standards for stationary gas emissions EN-1948:1996 and US EPA 1613 (fly ashes). Final extracts were analyzed by both high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC-HRMS) and high resolution gas chromatography coupled to ion trap tandem mass spectrometry (HRGC-ITMS/MS). Preliminary results revealed emission levels of 1-30.3 ng I-TEQ/Nm3 depending on whether or not an air pollution control system (APCS) was installed. Fly ashes contained 8.5-68 ng I-TEQ/g. Critical issues that should be addressed in an assessment and in developing waste management plans in Colombia are discussed.

Surveillance programme on dioxin levels in soils in the Campo de Gibraltar (southwest Spain)

The results of an epidemiologic study undertaken by the Spanish Council for Scientific Research (CSIC) after commission by the Spanish Parliament indicated that Huelva and Cádiz were the zones in Andalusia with elevated risk of cancer. A 6% (women) and 10% (men) cancer mortality excess was observed with respect to the other six Andalusian provinces. Huelva and Cádiz are located in the south-western region of Spain, and are characterized by a strong industrial activity concentrated in several industrial sites. This situation led to two environmental surveys in these areas, in which the presence of dioxins was studied among other parameters. A PCDD/F assessment in soils of the Campo de Gibraltar (Cádiz) was carried out from June 2003 to June 2004. A total of 20 samples were collected in this study divided in two sampling campaigns. The first 10 samples were taken in locations affected by high industrial activity zones as well as in landfills (hotspots). The rest of the samples were collected in areas that were not expected to be contaminated, such as agricultural zones and forests. I-TEQ values of the samples ranged from 0.26 to 15.08 ng/kg dm. In all, 85% of the samples were below the limit of 5 ng I-TEQ/kg I-TEQ concentrations of three samples only surpassed this limit. These zones corresponded to a landfill, a quarry used for dumping chemical product containers and a sample from the sewage system of the industrial site. These sites were used neither for agricultural nor for public purposes.

Development of new cleanup method of polychlorinated dibenzo-p-dioxins/dibenzofurans in fish by freezing-lipid filtration

Freezing-lipid filtration as a new method has been developed for the rapid determination of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) in biological samples. This method can effectively reduce the time of sample pretreatment, labor and amount of solvents compared with conventional methods. By freezing-lipid filtration procedure, about 90% of lipids in extract could be removed without any significant loss of PCDD/Fs. For further cleanup of extracts after freezing-lipid filtration, automatic parallel LC columns including silica gel, alumina and carbon columns were applied. During automatic parallel LC columns cleanup, most of co-extracted interferences such as residue lipids and fatty acids could be eliminated and dioxins could be separated from many other dioxin-like congeners such as polychlorinated biphenyls by this procedure. The extracts after cleanup were analyzed by high-resolution gas chromatography (HRGC)/high-resolution mass spectrometry (HRMS) using an isotope dilution method. The average recoveries and relative standard deviation (R.S.D.) of 17 native congeners in the spiked fish samples at 8-80 pg/g (n=3) were ranged between 85.3 and 117.2% and 5.7-20.3%, respectively.

Suitability of tandem-in-time mass spectrometry for polybrominated diphenylether measurement in fish and shellfish samples: Comparison with high resolution mass spectrometry

The first part of the present study focused on the development of an alternative automated sample preparation method for the measurement of selected polybrominated diphenyl ethers (PBDEs) in fish and shellfish. A previously developed automated method has been further optimized and simplified to decrease blank levels and cost. Sorbent and solvent quantities have been significantly reduced without altering extract quality. The second part of the study consisted of comparing tandem-in-time quadrupole ion storage mass spectrometry (QISTMS/MS) to high resolution mass spectrometry (HRMS) for the isotope dilution (ID) measurement step after gas chromatography (GC) separation. Both mass spectrometric methods performed similarly in terms of accuracy but better precision was observed for HRMS. Although better sensitivity can be attained with the high resolution sector instrument, method limits of quantification (mLOQs) were very similar for both approaches as they were dependent on the procedural blanks levels. The mLOQ values ranged between 0.04 and 3.56 ng/g fat, depending on the congener. They allowed the unambiguous identification and quantification of all target analytes, except for BDE-183, in most considered fish extracts. An analytical procedure based on rapid automated sample preparation and QISTMS/MS appeared to be suitable for the measurement of PBDEs in fish and shellfish speciment under quality assurance/quality control (QA/QC) criteria.

Polychlorinated dibenzo-p-dioxins, dibenzofurans and 'dioxin-like' PCBs in flue gas emissions from municipal waste management plants

The aim of this work is to give representative data on polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyl (PCBs) from stack gas emissions of an urban solid waste management plant which has to comply with the limit of 0.1 ng I-TEQ/Nm3. In particular, the study is focused on 29 target compounds, the seventeen 2,3,7,8-PCDDs/Fs, four non-ortho PCBs and eight mono-ortho PCBs which configure so-called 'dioxin-like' PCBs (DL-PCBs). To this end, emission measurements were performed during one year over the three operating combustion lines in a selected waste management plant. In general, accurate methodology allowed characterizing all target compounds in almost all the samples analyzed. In addition, a typical pattern for DL-PCBs is reported. The pattern presented PCB #118 to be the highest, nevertheless the figures demonstrated DL-PCBs contribution to the total TEQ around 3% being PCB #126 the most important congener due to its TEF of 0.1. Finally, remarkable differences were achieved in comparison with both environmental and biological samples such as soils, sediments, human milk or fish since these matrices may present DL-PCB contribution to the total TEQ up to 77%.