dl-PCB Concentrations Research Articles

Temporal variations in airborne PCDD/F and dl-PCB concentrations surrounding the dioxin-remediated areas in Da Nang, Vietnam, and health risk assessments.

The air pollution levels from polychlorodibenzo-p-dioxins/polychlorodibenzofurans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) in three residential areas located north, west, and south of the Da Nang airport were determined by using passive air samplers containing polyurethane foam (PUF) discs with 3-month sampling intervals from 2017 to 2020. The total toxic equivalents (∑TEQs) of the PCDD/Fs and dl-PCBs, using WHO2005-TEFs, were highest north of the airport (134 to 10610fg WHO-TEQ/PUF day, with an average of 1108fg WHO-TEQ/PUF day). The ∑TEQs were lower west of the airport, between 159 and 381fg WHO-TEQ/PUF day and averaged 230fg WHO-TEQ/PUF day. The lowest ∑TEQs occurred south of the airport, with ranges of 76 and 331fg WHO-TEQ/PUF day and an average of 152fg WHO-TEQ/PUF day. Construction activities, including excavation and transportation of dioxin-contaminated soil north of the airport, have increased airborne PCDD/F and dl-PCB contamination and health risks. The average daily doses of PCDD/Fs and dl-PCBs through inhalation (ADDA) for residents located north of the airport were the highest (10.9 to 3434fg WHO-TEQ/kg BW/day and average: 597fg WHO-TEQ/kg BW/day). Residents located west of the airport faced lower health risks (13-123fg WHO-TEQ/kg BW/day and average: 39fg WHO-TEQ/kg BW/day). Residents south of the airport were exposed to a minimum of 6.2-107fg WHO-TEQ/kg BW/day, with an average of 28fg WHO-TEQ/kg BW/day. The maximum and average ADDA values for residents north of the airport exceeded 10% of the tolerable daily intake (TDI) recommended by the WHO (100-400fg WHO-TEQ/kg BW/day). In comparison, all the ADDA values for residents located west and south of the airport were less than and within 10% of the TDI.

Temporal, spatial, and seasonal variations in airborne PCDD/F and dl-PCB concentrations around Bien Hoa hot spot, Vietnam, and health risk assessments

Passive air samplers were used to monitor polychlorodibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) between 2020 and 2022 in four residential areas around Bien Hoa hot spot (BHS) including Trung Dung (TD), Tan Phong (TP), Quang Vinh (QV), and Buu Long (BL). The total toxic equivalents of PCDD/Fs and dl-PCBs (∑TEQs) were highest in the TD area, from 284 to 642 fg TEQ/PUF day. Next was the QV area, where ∑TEQs ranged from 229 to 569 fg TEQ/PUF day. Then, ∑TEQs varied from 205 to 503 fg TEQ/PUF day in the TP area. The lowest ∑TEQs were between 179 and 385 fg TEQ/PUF day in the BL area. The temporal, spatial, and seasonal variations in concentrations of PCDD/Fs and dl-PCBs were related to the prevailing wind direction and the distance from each area to the dioxin hot spot. The average ∑TEQs for all four areas surrounding BHS in the dry season (423 fg TEQ/PUF day) were 1.4 times higher than in the rainy season (303 fg TEQ/PUF day). Health risk assessments from airborne dioxin exposure were estimated using the average daily doses through inhalation (ADDI). The ADDI for residents surrounding BHS ranged from 14.6 to 208 fg TEQ/kg BW/day. The ADDI values by areas were as follows: 23.2–208 fg TEQ/kg BW/day in the TD, 18.7–184 fg TEQ/kg BW/day in the QV, 16.7–163 fg TEQ/kg BW/day in the TP, and 14.6–125 fg TEQ/kg BW/day in the BL. These ADDI values remained within and below the 10% threshold of the WHO-recommended tolerable daily intake (100–400 fg TEQ/kg BW/day). It is necessary to control the excavation activities inside the BHS and cover the temporary storage sites of dioxin-contaminated materials to minimize the emissions of PCDD/Fs and dl-PCB into the ambient air.

Characterization, source and risk assessments of sediment contaminants (PCDD/Fs, DL-PCBs, PAHs, PCBs, OCPs, metals) in the urban water supply area

Water resources are becoming more valuable day by day. They need to evaluate the pollution and risk situations of the sources that supply water in detail. It is aimed to determine the level of POPs (PCDD/Fs, DL-PCBs, PAHs, PCBs, and OCPs) and metals, which are persistent pollutants, in the surface sediments taken from Yuvacık lake to reveal their possible sources, and to make toxicological and ecological risk assessments of sediment quality. It is one of the most comprehensive studies on the sediment scale for a drinking water source and is a first for the study area. Seventeen 2,3,7,8-substituted PCDD/Fs were analyzed with US EPA method (M.1613). The concentrations of all POPs were determined by GC-MS/MS. The range of ∑PCDD/F is 3.171 (Y8) to 28.42 (Y10) pg/g, with the highest concentrations of OCDD and 1234678-HpCDF compounds. Total DL-PCB concentrations 6.369 (Y8) to 37.41 (Y9) pg/g Total PAH concentrations in the samples ranged from 36.97 ng/g (Y1) to 81.38 ng/g (Y10). The PAH compounds with the highest concentrations at all sampled points were Phenanthrene 3141 (Y7) - 21,636 (Y10) and Naphthalene (11.40–19.41) ng/g. Total OCP concentrations ranged from 1.045 ng/g (Y8) to 4.179 ng/g (Y2), while total PCB concentrations ranged from 0.308 (Y1) to 1.55029 (Y9) ng/g. DDT p,p (0.4078–3.2544 ng/g) has the highest concentration among OCPs. PCB 101, 153, 138, and 180 are the highest detected PCB congeners. As a result of the source analysis, three different main sources were determined for all pollutant groups. They show accumulation in the sediment as a result of long-distance atmospheric transport. Toxicological values were found below acceptable limits. The main metals posing ecological risk were Ag, Cu, and Cd. Monitoring of POPs and assessing their toxicological and ecological risks are important for planning water resources and should be applied especially for critical basins.

Levels of dioxins and dioxin-like polychlorinated biphenyls in seawater from the Hornsund fjord (SW Svalbard)

Knowledge of contaminant distribution is important, particularly in the vulnerable first results about the occurrence of seventeen polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans and twelve dioxin-like polychlorinated biphenyls in arctic fjord seawater are reported. The contaminants were measured in 10 samples of suspended particulate matter collected in Hornsund (Svalbard). The ∑PCDD/F and ∑dl-PCB concentrations ranged from 0.066 to 231.47 pg/L and from 2.43 to 46.43 pg/L respectively. In terms of total PCDD/Fs, in general highly chlorinated PCDFs constituted the most significant fraction. Among dl-PCB compounds, PCB118 was the dominant congener. The toxicity equivalent for the samples ranged from 0.0008 to 1.90 pg I-TEQ/L for ∑PCDD/Fs, while for ∑dl-PCB it ranged from 0.0002 to 0.024 pg WHO05-TEQ/L. High concentrations of dioxins and dl-PCBs in some samples indicated that those contaminants could pose a threat to marine biota.

Levels of polychlorinated biphenyls and organochlorine pesticides in donkey milk: Correlation with the infection level by intestinal strongyles

AimThe study aimed at evaluating the concentration levels of organochlorine pollutants in donkey milk and their modulation on the intestinal strongyle infection. Risk evaluation for consumer health was also investigated. MethodsWe analyzed milk of grazing donkeys living in areas of Southern of Italy affected by organochlorine compounds environmental pollution and parasite infection. The presence of pollutants was assessed through summary statistics; regression analysis of intestinal strongyle on pollutant concentration was performed to investigate the relationship between the two variables. ResultsPCB concentrations (mainly non-dioxin-like (ndl)-PCBs) were higher than OCP ones. Mean values of ndl-PCBs across areas ranged from 93.13 to 263.64 ng g−1. In all sample units we detected the six indicator PCBs with the prevalence of the PCB 153, followed by the PCB 28 and the PCB 101. Among the dioxin-like (dl)-PCBs, non-ortho PCB 169, 77 and 126 were assessed in some milk samples; in all areas we detected the mono-ortho PCB 118 and PCB 105. Positive correlation between infection level and six indicator PCBs as well as between the former and HCB, on WW and LW, were observed (at least statistically significant at 5 percent). In some cases, Dl-PCB concentrations emerged as dangerous given the EU maximum residue limit for PCDD/Fs and dl-PCBs. ConclusionEvidence supports the hypothesis of an immunosuppressive role of organochlorine pollutants; risk evaluation reveals the potential health impact of dl-PCB intake, particularly for major donkey milk consumers such as infants, children with cow milk and multiple food intolerance, and elders.

Background levels of dioxin-like polychlorinated biphenyls (dlPCBs), polychlorinated, polybrominated and mixed halogenated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, PBDD/Fs & PXDD/Fs) in sera of pregnant women in Accra, Ghana

Human exposure data on dioxins and dioxin-like compounds (DLCs) in Ghana are limited. Based on health risks associated with dioxins and DLCs, the impact of maternal body burdens on foetal exposure is significant. This is the first study that assesses polychlorinated, polybrominated and mixed halogenated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, PBDD/Fs and PXDD/Fs), and dioxin-like polychlorinated biphenyls (dlPCBs) in sera of primiparous Ghanaians. Our sample selection includes 34 participants from two municipalities (Accra and Tema), and explores contributions from environmental and dietary exposures using questionnaire data. Sample preparation involved C18 solid phase extraction, purification with acidified silica and lipid removal cartridges, and detection with gas chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry. The calculated average toxic equivalent concentration was 5.3 pg TEQ/g lw, with contributions from dlPCBs (1.25 pg TEQ/g lw), PCDD/Fs (3.10 pg TEQ/g lw), PBDD/Fs (0.49 pg TEQ/g lw) and PXDD/Fs (0.50 pg TEQ/g lw). The calculated total TEQ concentration was lower than background TEQ concentrations reported in sera of pregnant women globally. Positive correlations were obtained for total dioxins and DLC concentrations with age and Body Mass Index (BMI). Dietary intake of seafood and dairy products had a strong influence on PCDD/F and dlPCB concentrations. Statistically significant differences were observed for dioxins and DLCs in participants from Accra (in close proximity to Agbogbloshie e-waste site) and Tema. Given the significant TEQ contribution of PBDD/Fs and PXDD/Fs (~20%), it is essential to explore these classes of dioxins and DLCs in future biomonitoring studies as they may pose health risks, and add extra diagnostic information in source exposure investigations.

Characterization of PCDD/Fs and dl-PCBs emission from combustion of PCB-containing oil in a fluidized-bed incinerator

Emissions of PCDD/Fs and dl-PCBs from the combustion of PCB-containing oil in a hazardous waste incinerator are characterized. Flue gas samples are simultaneously taken at three points, including the outlet of ultrasonic wet scrubber, the outlet of heat exchanger and stack. In addition, solid matter samples including incinerator bottom ash, wet scrubber sludge, heat exchanger ash and baghouse ash are also collected. The results indicate that TEQ concentration (PCDD/Fs + dl-PCBs) measured in stack from the combustion of PCB-containing oil is 0.51 ng WHO-TEQ/Nm3. For the solid matter, PCDD/F and dl-PCB concentrations of baghouse ash and wet scrubber sludge are significantly higher than those measured in bottom and heat exchanger ashes. The total removal efficiencies of PCDD/Fs + dl-PCBs achieved with bag filtration (BF) + activated carbon injection (ACI) reaches 65.0%. The emission factors of PCDD/Fs and dl-PCBs from incinerating PCB-containing oil are 1.05 and 0.08 ng WHO-TEQ/L, respectively. The overall PCDD/Fs and dl-PCBs destruction efficiencies achieved with fluidized-bed incinerator reach 99.87% and 99.9998%, respectively, which demonstrates that incineration is an effective engineering practice for treating PCB-containing oil. Moreover, this is the first study suggesting the ratios of PCB-114/(PCB-126+ PCB-114) and PCB-157/(PCB-169+ PCB-157) as indicators to distinguish the emission source of dl-PCB from combustion process and technical mixture evaporation in diagnostic ratio analysis.

Evaluation of atmospheric concentrations of dl-PCBs comparing to PCDD/F compounds in Istanbul, Turkey

<p>In this study, the seasonal variation of atmospheric concentrations of PCDD/F and Dl-PCB and the effect of meteorological factors on concentration were investigated. Ambient air samples were collected monthly between May 2011 and October 2013 by using high volume samplers. Based on these samples, average PCDD/F and dl-PCB concentrations were obtained as 1482 fg/m3 and 4983 fg/m3 respectively. PCDD/F congeners did show seasonal variations. 58% share in total PCDD/Fs belongs to winter season while 4% to summer season. No significant seasonal change has been observed for dl-PCBs. 92% (1397 fg/m3) of PCDD/Fs were detected in particulate phase while 20% (926 fg/m3) of dl-PCBs were found in particulate phase. Strong negative correlations were obtained between all homolog groups and T, UV, SR. Correlation between five-chlorinated dl-PCBs, the most abandoned homolog group, with T, UV and SR generated positive meaningful correlation. No meaningful correlations were observed with other parameters. Correlations with particle phase were found to be more meaningful compared to gas phase for both PCDD/Fs and dl-PCBs.</p>

Preliminary investigation of polychlorinated dibenzo-p-dioxin and dibenzofuran, polychlorinated naphthalene, and dioxin-like polychlorinated biphenyl concentrations in ambient air in an industrial park at the northeastern edge of the Tibet–Qinghai Plateau, China

Ambient air samples collected in an industrial park at the northeastern edge of the Tibet–Qinghai Plateau (China) were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated naphthalenes (PCNs), and dioxin-like (dl) polychlorinated biphenyls (PCBs). The PCDD/F, PCN, and dl-PCB concentrations were 1.18–2.18, 21.9–75.1, and 0.49–0.90 pg/m3, respectively. The concentrations of these compounds were clearly higher than that observed at a remote site and were comparable with those found in ambient air in industrial areas in other locations. A principal component analysis indicated that emissions from local industrial sites (a secondary aluminum smelter, a cement kiln, and a lead–zinc smelter) at which thermal processes are performed were the sources of PCDD/Fs to the air. The combustion-related PCN congener profiles suggested that industrial thermal processes strongly affect PCN concentrations in ambient air at the industrial park. The results clearly indicated that the industrial park is a source of environmental PCDD/Fs and PCNs at the northeastern edge of the Tibet–Qinghai Plateau.

Temporal trends in dioxin-like polychlorinated biphenyl concentrations in serum from the general population of Shandong Province, China: A longitudinal study from 2011 to 2017

Temporal changes in the concentrations of dioxin-like (DL) polychlorinated biphenyls (PCBs) in environmental and biological matrices in China are not well understood. We determined the DL-PCB concentrations in pooled serum samples from the general population of Weifang City, Shandong Province, China in 2011 (n = 305) and 2017 (n = 495). The total DL-PCB concentration was 3.48 ± 1.31 ng/g lipid (mean ± standard deviation) in 2011 and 2.82 ± 1.73 ng/g lipid (19% lower) in 2017, but the difference was not statistically significant (p = 0.347). The DL-PCB concentrations and toxic equivalent concentrations were much lower in the serum from Weifang residents than have been found in serum from the inhabitants of other parts of the world. The concentrations of most of the DL-PCB congeners followed different downward temporal trends, but the PCB-118 concentration was higher in 2017 than in 2011. The temporal changes in the PCB concentrations and compositions in the samples from the general population of Weifang indicated that there may a new source of unintentionally produced PCBs in Weifang.

Occurrence of PCDD/PCDFs, dioxin-like PCBs, and PBDEs in surface sediments from the Neva River and the Eastern Gulf of Finland (Russia).

A total of 26 samples of surface sediments collected in the Neva River (including the St. Petersburg city area) and in the Russian part of the Gulf of Finland were analyzed for 17 polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), 12 dioxin-like polychlorinated biphenyls (dl-PCBs), and 10 polybrominated diphenyl ethers (PBDEs). The concentrations of total PCDD/Fs and dl-PCBs in sediments ranged from < 0.05 to 219pgg-1d.w. and from 44 to 246,600pgg-1d.w. respectively. The total World Health Organization toxic equivalent (WHO-TEQPCDD/F + PCB) values varied between 0.01 and 59.0pgg-1. In the majority of cases, the PCDD/F and dl-PCB concentrations do not exceed the threshold effect level (TEL) recommended by Helsinki Commission (HELCOM) as quantitative target for the sum of PCDD/Fs and dl-PCBs. The congener profile indicates that combustion is the primary source of PCDD/Fs in most of the studied samples. For the PCBs, the historical use of technical PCB products was identified as the major source. ΣPBDE10 concentrations ranged from 0.004 to 1.8ngg-1d.w. The congener profile results show that BDE-47 (tetra-BDE) is the dominant congener in sediment samples. According to the sediment and water quality guidelines established in the EU (PNEC) and in Canada (FEQG), all the samples studied can be classified as lowly contaminated by PBDEs. The sediment concentrations of PCDD/Fs, dl-PCBs, and PBDEs measured in this study were comparable to or lower than those reported for other areas of the Baltic Sea.

Chemical indicators of exposure to polychlorodibenzo-p-dioxins, polychlorodibenzofurans and polychlorobiphenyls in breast milk samples from mothers residing in Trento, Italy, and neighboring country municipalities

ABSTRACTA human biomonitoring study was carried out in the province of Trento, northern Italy, on two groups of women residing in areas with presumably different levels of exposure to polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs) and polychlorobiphenyls (PCBs). The aim was characterization of the possible impact of a steel plant and an urban environment on the internal doses of these contaminants. The areas investigated were the following: (i) the municipality of Borgo Valsugana, where a steel plant has been operating for the last 30 years, and (ii) the city of Trento. Ten women were enrolled from each area, and breast milk samples were collected from each woman. The amounts of PCDDs, PCDFs and PCBs were analyzed in all samples, and the data obtained were evaluated by descriptive and multivariate statistical approaches. For all samples, the concentrations observed were in the current acceptable concentration range observed in Europe. The descriptive statistics, however, clearly showed that some differences existed between the two groups: the PCDD, PCDF and DL-PCB concentrations were consistently higher in the Trento group of women living in the area surrounding the steel plant. Congener-profile analysis was carried out on both groups, and an appropriate multivariate approach, such as classical factor analysis (CFA), was used to investigate possible differential exposure sources. The application of this approach made it possible to show the quantitative and qualitative differences that characterized the two areas.

Field investigation to determine the environmental source of PCBs in a pig farm

During a national monitoring plan, a pork fat sample was declared non-compliant for the sum of dioxins and PCB-DL (EU regulation). The National Reference Laboratory together with competent authorities conducted extended investigations to determine rapidly the contamination source at the farm level. A range of samples (n = 129), representative of potential contamination sources, was selected for further characterization (fat, feed, materials, dust, soil) and was analyzed for PCDD/Fs and DL-PCBs by GC-HRMS. A hot spot was localized in the farm, which corresponded to a pre-feed storage tank, the paints of which presented huge DL-PCB concentrations (>1 × 106 pg g−1), responsible for the contamination. The present case report describes a new source of PCB contamination, previously undescribed.

Characterization of PCDD/Fs and dioxin-like PCBs emitted from two woodchip boilers in Taiwan

This study investigates the formation and removal of PCDD/Fs and dl-PCBs in two woodchips boilers during different operating periods. Results indicate that combustion condition affects PCDD/F and dl-PCB formation within the woodchip combustion process. PCDD/F and dl-PCB concentrations during the start-up period are much higher than those measured during normal operation and shut-down periods due to unstable combustion. PCDD/F and dl-PCB concentrations at APCDs inlet of Plant A are significantly higher than that of Plant B due to the lower combustion temperature (500–850 °C) compared with Plant B (850–925 °C). Major PCDD/F congeners at APCDs inlet of both plants during normal operation are O8CDD, 1,2,3,4,6,7,8-H7CDD and 1,2,3,4,6,7,8-H7CDF, while major dl-PCBs are TeCB-77, PeCB-118 and PeCB-126. The removal efficiencies of PCDD/F and PCBs achieved with the APCDs of Plant A are 95.6% and 88.6%, respectively, while those of Plant B are 99.3% and 94.9%. Possibly, the AC concentration of Plant A exceeds the optimal AC concentration and, PCDD/Fs and dl-PCBs might be formed because the AC injected can supply additional reaction area and carbon source. Also, this may be due to different operating temperatures of APCDs, which affects removal efficiency of PCDD/F and dl-PCB congeners. The emission factors (PCDD/Fs + dl-PCBs) of Plants A and B are calculated as 17.86 and 1.25 μg I-TEQ/ton, respectively. Concentrations of PCDD/Fs in the BF ash of Plants A and B during normal operation are measured as 98.57 and 38.06 ng I-TEQ/g, which are significantly higher than the standard limit (1.0 ng I-TEQ/g) promulgated by Taiwan EPA.

Exposure Route of Dioxin-like Polychlorinated Biphenyls in Hair Based on Passive Sampling

The main exposure pathways of DL-PCBs in local population were studied by analyzing the levels, distributions and relationships of DL-PCBs in pooled tree bark samples and hair samples collected in Kaiyuan, Yunnan Province, China. The results indicated that the concentrations of DL-PCBs in bark and hair samples were 4.0 pg·g-1 to 88.9 pg·g-1 and 4.1 pg·g-1 to 19.3 pg·g-1, respectively, suggesting the pollution levels of DL-PCBs were relatively low in local environment and human body. The predominant PCB congeners in bark and hair was PCB-118, contributing 48% of the total DL-PCB concentrations in the bark samples and 61% of the total DL-PCB concentrations in the hair samples. The DL-PCB congeners in tree bark might had the same sources and these compounds might be derived from atmospheric long-range transport. External and internal exposures were responsible for the DL-PCBs concentrations in hair, and external exposure contributed more to low chlorinated PCBs than to high chlorinated PCBs.

PCDD/Fs and dl-PCBs concentrations in water samples of Taiwan

Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (dioxin-like PCBs) have received much public concern worldwide due to their persistence and toxicity. The presence of these compounds in environmental matrices, especially in water bodies, enhances the risk of human exposure to these toxic pollutants. In this study, seventeen 2,3,7,8 chlorinated PCDD/Fs and twelve dl-PCBs were measured in 11 groundwater samples collected throughout Taiwan and 2 surface water samples collected in northern Taiwan. PCDD/F and PCB concentrations in two surface water samples are relatively low, with the average concentrations of 0.038 and 0.001 pg WHO-TEQ/L (7.474 and 1.862 pg L−1), respectively. As for groundwater samples, PCDD/F concentrations measured range from 0.005 to 3.963 pg WHO-TEQ/L, while dl-PCB concentrations range from 2.5 × 10−5 to 0.189 pg WHO-TEQ/L. Total WHO-TEQ concentrations range from 0.005 to 3.963 pg WHO-TEQ/L, reflecting serious contamination of PCDD/Fs and PCBs in groundwater at some sampling sites. In term of total PCDD/Fs, PCDDs constitute a significant fraction (77.3%), and OCDD is most abundant, followed by HpCDD/Fs and HxCDD/Fs. PCB 118 is dominant among 12 dl-PCBs measured, followed by PCB 105 and PCB 77. Solid-phase PCDD/Fs generally predominate in water samples and PCDFs are of slightly lower distribution in solid phase in comparison with PCDDs, while PCBs are mainly distributed in dissolved phase. Results of principal component analysis (PCA) indicate that use of PCP and Na-PCP, thermal processes and PCBs-containing products might be the major sources of PCDD/Fs and PCBs in water samples measured.

Polychlorinated Dibenzo-P-Dioxins (PCDD), Polychlorinated Dibenzofurans (PCDF) and Dioxin-Like Polychlorinated Biphenyls (Dl-PCB) in the Baltic and Arctic Fish and the Further Trophic Transfer of these Pollutants to Seabirds

The study presents the analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F) and dioxin-like polychlorinated biphenyls (dl-PCB) in fish and seabirds from the Baltic Sea area and the Arctic region (the Svalbard Archipelago). Long-time studies revealed no significant temporal trends in PCDD/F and dl-PCB concentrations in fish from the Baltic Sea. Trace amounts of PCDD/F were detected in the Arctic fish as an evidence of their anthropogenic sources from the temperate zone, however congener profile in the cod was entirely different than in the Baltic fish. On the contrary, both concentrations and profiles of dl-PCB were comparable in cod from the Baltic Sea and from the polar region. PCDD/F`s congener profile in African penguin`s tissues breed in captivity and fed only by herring exhibited a clear resemblance to the profiles measured in herring. This indicates a relevant impact of diet (fish) on PCDD/F`s level in seabirds. Diet impact on the further transfer of these xenobiotics in the trophic chain, evidenced in the presented study, appears to be of the particular relevance due to the human health.

Levels of dioxins and dioxin-like PCBs in food of animal origin in the Netherlands during the period 2001–2011

ABSTRACTThe aim of this study was to assess levels of dioxins (polychlorinated dibenzo-p-dioxins and dibenzofurans, PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) (DL-PCBs) in food of animal origin produced in the Netherlands, including potential trends in time. Test results from about 2500 samples of animal derived food products (beef, veal, lamb, chicken, pork, deer, milk and eggs), sampled for the National Residue Monitoring Plan from 2001–2011, were evaluated. Most samples were screened with a bioassay and, if suspected, analysed by GC-HRMS. The fraction of samples which were non-compliant with European maximum levels was rather low, being below 1% for most food products, except for lamb. Exceedance of action levels was particularly observed for lamb and beef. To obtain an insight into background levels, a randomly taken part of the samples was directly analysed by GC-HRMS. In general, only minor decreases in mean PCDD/F and DL-PCB concentrations could be observed for the period 2001–2011. This may be due to a plateauing of current background levels but also to factors like the sensitivity of the analytical method.

Modelling scenarios on feed-to-fillet transfer of dioxins and dioxin-like PCBs in future feeds to farmed Atlantic salmon (Salmo salar)

The salmon feed composition has changed the last decade with a replacement of traditionally use of fish oil and fishmeal diets with vegetable ingredients and the use decontaminated fish oils, causing reduced concentrations of dioxins and dioxin-like PCBs in farmed Norwegian Atlantic salmon. The development of novel salmon feeds has prompted the need for prediction on dioxins and dl-PCB concentrations in future farmed salmon. Prediction on fillet dioxins and dl-PCB concentrations from different feed composition scenarios are made using a simple one-compartmental transfer model based on earlier established dioxin and dl-PCB congener specific uptake and elimination kinetics rates. The model is validated with two independent feeding trials, with a significant linear correlation (r2 = 0.96, y = 1.0x, p < 0.0001, n = 116) between observed and predicted values. Model fillet predictions are made for the following four scenarios; (1) general feed composition of 1999, (2) feed composition of 2013, (3) future feed composition with high fish oil and meal replacement, (4) future feed composition with high fish oil and meal replacement and decontaminated fish oil. Model predictions of fillet dioxin and dl-PCB concentrations from 1999 (1.05 ng WHO2005-TEQs kg−1ww) and 2013 (0.57 ng WHO2005-TEQs kg−1ww) are in line with the data observed in national surveillance programs of those years (1.1 and 0.52 ng WHO2005-TEQs kg−1ww, respectively). Future use of high replacement and decontaminated oils feeds gave predicted fillet concentrations of 0.27 ng WHO2005-TEQs kg−1ww, which is near the limit of quantification.

Dietary intake of dioxins and dioxin-like PCBs by residents at two typical sites in China: A review

Polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are referred to as dioxin-like compounds due to their structural similarity. There have been increasing concerns about dioxin-like compounds because they are highly toxic and persistent compounds that may be harmful to human health and the environment. PCDD/Fs and dl-PCBs can be unintentionally produced as byproducts from certain thermal processes such as waste incineration, metal smelting and open burning as well as from manufacture of certain chemicals and pulp and paper production. They can also be found in electrical equipment containing polychlorinated biphenyls (PCBs). PCDD/Fs and dl-PCBs released in the environment can accumulate in the food chain. Human exposure to PCDD/Fs and dl-PCBs mainly through the dietary intake. This paper presents an overview on the available literatures on PCDD/F and dl-PCB levels in foodstuffs at dioxin-like compound polluted sites in China. Although various dioxin-like compound sources in China have been reported and relatively high levels of PCDD/Fs and dl-PCBs were found in the environmental matrices near dioxin-like compound sources, data on PCDD/F and dl-PCB concentrations in foodstuffs in dioxin-like compound polluted areas in China were relatively few. PCDD/Fs and dl-PCBs were found higher levels in the foodstuffs at E-waste recycling sites such as Taizhou in Zhejiang Province and Guiyu in Guangdong Province than the control areas. Moreover, higher levels of PCDD/Fs were also found in foodstuffs in Ya-Er lake than the control area because the water of Ya-Er lake had been continuously polluted by a chemical factory situated on the bank of the lake. It is estimated that dietary intake of PCDD/Fs and dl-PCBs by the residents at the two typical dioxin-like compound polluted sites exceeded the international limits and were also higher than the average consumer dietary intake of PCDD/Fs and dl-PCBs in China. It indicates that the residents at the two typical dioxin-like compound polluted sites in China may have health risks. Therefore, more attention should be attracted on the human health risks at dioxin-like compound polluted areas in China. Large scale investigation on PCDD/F and dl-PCB levels in foodstuffs in various dioxin-like compound polluted areas in China is needed to be conducted.