Total TEQ Research Articles

Altitudinal distributions of PCDD/Fs, dioxin-like PCBs and PCNs in soil and yak samples from Wolong high mountain area, eastern Tibet-Qinghai Plateau, China

Topsoil along the altitudinal gradient (2086–4487m above sea level) and yak samples, collected from Wolong high mountain area of Sichuan Province, western China, were analyzed for polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polychlorinated naphthalenes (PCNs) using HRGC–HRMS. The total concentrations of PCDD/Fs, dl-PCBs, and PCNs in soils were: 2.48–4.30pgg−1 dw (dry weight), 7.6–10.5pgg−1 dw, and 13.0–29.0pgg−1 dw, respectively; the greatest concentrations were found at sampling sites of 3927m, 4487m and 3345m, correspondingly. The total PCDD/Fs and dl-PCBs concentrations showed positive correlations with increasing altitudinal gradient. The congener profiles of both 2,3,7,8-PCDD/Fs and dl-PCBs at different altitudes showed similar patterns. PCNs were dominated by Tri-CNs. The long-range atmospheric transport and subsequent aerial deposition are likely the sources for these POPs in area examined. The total TEQs in soils were in the range of 0.28–0.42pgg−1 dw, and the total TEQs in the yak muscle and fatty tissue samples were 3.81–4.09pgTEQg−1 lipid weight. The daily intake of TEQs was estimated to be below the WHO's tolerable daily intake according to the local people's dietary habits in Wolong area, which is unlikely to cause any adverse health effects to the yak muscle consuming people.

Assessing the fish consumption beneficial use impairment in the Bay of Quinte

The state of contamination in Bay of Quinte fish was assessed to determine whether delisting criteria have been met, and to recommend further studies/actions to be undertaken. We examined fish contaminant data collected by the Ontario Ministry of the Environment between 1975 and 2008 for seven sites in Lake Ontario including the Bay of Quinte. Where sufficient data was available, we tested for differences in recent years by examining the post-1998 data for Walleye, Smallmouth Bass, Yellow Perch and Brown Bullhead. Our analysis specifically focused on known contaminants of concern within the Bay of Quinte: polychlorinated biphenyls (PCBs), mercury (Hg), as well as Mirex which is known to originate from Lake Ontario. Insufficient data was available for the examination of total TEQs (dioxins, furans and dioxin-like PCBs). When appropriate, we used the general linear model (GLM) to compare contaminant concentrations among sites as a function of fish length. When no significant relationship between contaminant concentration and fish length was found, mean values among sites were compared using analysis of variance. While there were no significant differences for the majority of contaminants among sites, some species and contaminant combinations at one or more of the Bay of Quinte sites had elevated fish concentrations compared to some reference sites. For instance, mercury concentrations in Yellow Perch and Brown Bullhead at Quinte sites exceeded those from some reference sites. Current consumption restrictions for Brown Bullhead and Yellow Perch are more severe in the Upper Bay of Quinte compared to the other sites, indicating impacts of local sources. As a result, the fish consumption beneficial use impairment continues to be classified as impaired for the Bay of Quinte. As many sport fish such as Walleye and Smallmouth Bass are large, long-lived and potentially wide-ranging species, it is difficult to link contaminant concentrations to local sources. To investigate the impact of sources within the Upper Bay of Quinte, comparison of contaminants in sentinel fish collected on the same scale as the source of the contamination is recommended.

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 30.7years (18.0–38.0years), pre-pregnancy BMI of 23.3kg/m2 (18.0–40.2kg/m2), and 31% were smokers. Median total concentrations of PCDD/Fs and DL-PCBs were 6.9pgWHO-TEQ/g lipid and 2.1pgWHO-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.

Dietary intake of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by a population living in the vicinity of a hazardous waste incinerator. Assessment of the temporal trend

The concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were determined in a number of foodstuffs purchased in various locations near a hazardous waste incinerator (HWI) in Tarragona County (Catalonia, Spain). The dietary intake of PCDD/Fs by the population of the area under potential influence of the HWI was subsequently estimated. The results were compared with previous surveys performed in the same area in 1998 (baseline), 2002 and 2006. In the present study, the highest WHO-TEQ corresponded to industrial bakery (0.183ng/kg wet weight, ww), followed by fish (0.156ng/kg ww), oils and fats (0.112ng/kg fat weight), and seafood (0.065ng/kg ww). In contrast, the lowest values were observed in pulses and tubers (0.003ng/kg ww), and cereals and fruits (0.004ng/kg ww). The dietary intake of PCDD/Fs by the general population was 33.1pg WHO-TEQ/day, having fish and seafood (11.6pg WHO-TEQ), oils and fats (4.61pg WHO-TEQ), dairy products (3.79pg WHO-TEQ), and industrial bakery (3.49pg WHO-TEQ) as the groups showing the highest contribution to the total TEQ. The lowest daily contributions corresponded to pulses (0.08pg WHO-TEQ) and tubers (0.25pg WHO-TEQ). This intake was considerably lower than that found in the baseline study, 210.1pgI-TEQ/day, and also notably lower than that found in the 2002 survey (59.6pgI-TEQ/day), but slightly higher than the intake estimated in the 2006 survey, 27.8pgWHO-TEQ/day. The results of this study show that any increase potentially found in the biological monitoring of the general population living in the area under evaluation should not be attributed to dietary exposure to PCDD/Fs.

Development and validation of prediction models for blood concentrations of dioxins and PCBs using dietary intakes

BackgroundDioxins and PCBs accumulate in the food chain and might exert toxic effects in animals and humans. In large epidemiologic studies, exposure estimates of these compounds based on analyses of biological material might not be available or affordable. ObjectivesTo develop and then validate models for predicting concentrations of dioxins and PCBs in blood using a comprehensive food frequency questionnaire and blood concentrations. MethodsPrediction models were built on data from one study (n=195), and validated in an independent study group (n=66). We used linear regression to develop predictive models for dioxins and PCBs, both sums of congeners and 33 single congeners (7 and 10 polychlorinated dibenzo-p-dioxins and furans (PCDDs/PCDFs), 12 dioxin-like polychlorinated biphenyls (PCBs: 4 non-ortho and 8 mono-ortho), sum of all the 29 dioxin-like compounds (total TEQ) and sum of 4 non dioxin-like PCBs (∑ CB-101, 138, 153, 183=PCB4). We used the blood concentration and dietary intake of each of the above as dependent and independent variables, while sex, parity, age, place of living, smoking status, energy intake and education were covariates. We validated the models in a new study population comparing the predicted blood concentrations with the measured blood concentrations using correlation coefficients and Weighted Kappa (КW) as measures of agreement, considering КW>0.40 as successful prediction. ResultsThe models explained 78% (sum dioxin-like compounds), 76% (PCDDs), 76% (PCDFs), 74% (no-PCBs), 69% (mo-PCBs), 68% (PCB4) and 63% (CB-153) of the variance. In addition to dietary intake, age and sex were the most important covariates.The predicted blood concentrations were highly correlated with the measured values, with r=0.75 for dl-compounds 0.70 for PCB4, (p<0.001) and 0.66 (p<0.001) for CB-153. КW was 0.68 for sum dl-compounds 0.65 for both PCB4 and CB-153. Out of 33 congeners 16 (13dl-compounds and 3 ndl PCBs) had КW>0.40. ConclusionsThe models developed had high power to predict blood levels of dioxins and PCBs and to correctly rank subjects according to high or low exposure based on dietary intake and demographic information. These models underline the value of dietary intake data for use in investigations of associations between dioxin and PCB exposure and health outcomes in large epidemiological studies with limited biomaterial for chemical analysis.

Blood levels of PCDDs, PCDFs, and coplanar PCBs in Yusho mothers and their descendants: Association with fetal Yusho disease

Maternal exposure to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) may result in adverse health effects in their children. In Japan in 1968, an accidental human exposure to rice oil contaminated with PCDDs, PCDFs, and PCBs, led to the development of Yusho disease. Yusho mothers delivered descendants with low birth weights and hyperpigmented skin and mucosa, which are characteristic of fetal Yusho disease (FYD). The Yusho cohort was used to evaluate the effect of maternal exposure to PCDDs, PCDFs, and PCBs on the development of FYD. Blood samples, obtained from 64 Yusho mothers (117 descendants: 10 with FYD and 107 without FYD), were analyzed for congeners of seven PCDDs, 10 PCDFs, and four coplanar PCBs. We investigated the association between the maternal estimated blood levels of dioxins at delivery and the risk of fetal Yusho disease. We also studied the differences in dioxin blood levels in 24 mother–descendant pairs (5 with FYD and 19 without FYD). The estimated levels of total PCDD TEQ, total PCDF TEQ, total coplanar PCB TEQ, and total TEQ in the maternal blood at delivery were associated with significantly increased risk of FYD. The odds ratios, which present the risk of FYD for a 10-fold increase in blood dioxin, were largest for 1,2,3,6,7,8-HexaCDD (odds ratio=28.6, 95% confidence interval=1.67–489.9, p=0.02). The levels of 1,2,3,6,7,8-HexaCDD in both the Yusho mothers and their descendants with FYD were higher than the levels in those without FYD. These findings suggest that 1,2,3,6,7,8-HexaCDD is the most important causative congener for the development of FYD.

Seasonal variations in the levels of PCDD/Fs, PCBs and PBDEs in cows’ milk

The first detailed investigation into seasonal variations in PCDD/F, PCB and PBDE concentrations in cows’ milk from individual farms was conducted. From August 2009 milk samples were taken at 6weeks intervals from the bulk tank of 2farms over a period of one year. Samples of dietary inputs including commercial feed, grass, silage and soil were also collected at 6weekly intervals from each farm. Detailed animal husbandry information was additionally obtained. For all these samples total TEQ, ∑ICES6 and the ∑7 PBDE congeners was calculated. The results demonstrated that the concentrations of these sets of compounds fluctuate notably over short periods in cows’ milk. This variability was such that the highest observed concentrations were nearly double the lowest concentrations detected for both PCDD/Fs and PCBs and PBDEs. Fluctuations between extremes were observed over time periods as short as 6weeks. Some, but not all, of these variations may be explained by changes in the contaminant concentrations of dietary inputs consumed by the cattle. Changes in contaminant inputs from grass and silage were identified as being the most important source of these fluctuations. Given this variability, the results from PCDD/F and PCB and PBDE monitoring studies may be highly dependent upon when the individual samples were taken. The results have important implications for total diet studies and sampling design.

Analytical approach and occurrence for the determination of mass concentration of PCDD/PCDF and dl-PCB in flue gas emissions using long-term sampling devices

In this work, a reliable methodology for the simultaneous analysis of PCDD/PCDF and dioxin-like PCB (dl-PCB) in flue gas emissions collected using continuous sampling devices is proposed. The analytical scheme followed the minimum requirements described in the EU standard EN-1948:1,2,3,4 according to samples containing large amounts of dioxins and dl-PCBs or samples collected over a long period of time of about 4weeks. Parameters, such as reproducibility, precision, limits of detection (LOD), limits of quantification (LOQ), extract aliquot size, analytical blanks, extraction efficiency, as well as the amount of internal standards required for an accurate determination, were assessed.The findings demonstrate the suitability of the proposed analytical scheme for the analysis of PCDD/PCDF and PCB in samples collected using long-term sampling devices. The analysis of five different 5% v/v sample aliquots reported %RSD values lower than 10% for all of the 29 congeners at both low and high levels. Similarly, %RSD values were 3.2 and 2.0 for the low level samples and 0.9 and 1.1%RSD for the high level extracts for PCDD/PCDF and dl-PCB, respectively expressed in total TEQ units. Re-extraction provided values less than 3%, expressed in TEQ. Based on blank analyses, LOD values of 100pg I-TEQ for PCDD/PCDF and 10pg WHO-TEQ for dl-PCB were achieved when 5% v/v aliquots were analyzed.Finally, the proposed analytical approach was tested with samples from a wide range of combustion processes such as hazardous and municipal waste incinerators, as well as cement kilns (with and without waste co-incineration).

PCDDs, PCDFs, dioxin-like PCBs and indicator PCBs in soil from five selected areas in Slovakia

There is a lack of information regarding persistent organic pollutants (POPs) in soil from Slovakia. This paper reports the concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), 12 dioxin-like polychlorinated biphenyls (dl-PCBs) and 6 indicator PCBs associated with 32 soil samples collected in 2007 from areas in the vicinity up to several kilometres from four selected industrial PCDD/F sources in Slovakia and one background area.The results show that the total WHO1998-PCDD/F/dl-PCB-TEQ concentrations varied from 0.34 to 18.05pgg−1 dry weight (dw) and the average total TEQ concentrations in samples collected at the Šala, Košice, Krompachy and Dubová areas were 3.18, 2.64, 7.80, and 3.19pgg−1dw respectively. The average of the total WHO1998-TEQ values in three soil samples representing the background Starina area was 0.66pgg−1 dw. The predominant contaminants among 2,3,7,8-substituted PCDD/Fs, dl-PCB, and indicator PCBs was OCDD, PCB 118, and PCB 153 respectively. The major contributors to the TEQ were 2,3,4,7,8-PeCDF, PCB 126, 1,2,3,7,8-PeCDD, PCB 156 and 1,2,3,4,7,8-HxCDF+1,2,3,4,7,9-HxCDF in descending order.

Releases of Dioxin-like PCBs in Water, Soil and Residue Produced from High Thermal Processes and Waste Incinerators

This paper presents the results of DL-PCB releases to water, soil and residue from waste incinerators, crematorium and various industries such as cement, textile, paper and pulp, steel, thermal power plant, landfill sites and bricks kilns. Total TEQ as per WHO-TEFs (2006) in water, soil and residue ranged from 0.005 to 1.884pg/L, 0.007 to 33.041pg/g and 0.001 to 0.013pg/g, respectively. PCB #118 was the predominant mono-ortho congener; followed by PCB #105. PCB #77 exhibited the highest values amongst non-ortho PCBs in the samples collected.

Organohalogen exposure in a Eurasian Eagle owl (Bubo bubo) population from Southeastern Spain: Temporal–spatial trends and risk assessment

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine insecticides (OCs) were analysed in 58 Eurasian Eagle owl (Bubo bubo) unhatched eggs collected between 2004 and 2009 in Southeastern Spain. Levels of p,p′-DDE were found to be higher than in eggs laid by other European owls in the same decade, probably due to the greater agricultural activity in our study area. Compared to other European raptors, exposure to PCBs can be considered intermediate, but low to PBDEs. Land use differences and prey availability were the rationale to divide the study area in two subareas in further assessments. Temporal trends of HCB, p,p′-DDE, β-HCH, PCBs and PBDEs were significantly different in each subarea, generally increasing over time in the Southern but decreasing or remaining stable in the Northern. On the contrary, levels of cyclodienes tended to decrease in both subareas. Dietary shifts with a greater amount of birds are suggested as a cause for increasing organochlorine loads in raptors. This may explain the increasing trend in the Southern territories. However, due to the proximity of most of these nests to Cartagena, an important industrial city, increasing environmental pollution cannot be ruled out. Although average levels of the compounds analysed are below threshold levels, 17% of the samples exceeded 400pgg−1ww (wet weight), the LOAEC for Total TEQs. Moreover, a negative correlation between TEQ concentrations and the metabolizable fraction of PCBs (Fprob=0.0018) was found when TEQs values were above 10pgg−1ww. This could be indicative of hepatic enzymes induction in the birds exposed at higher concentrations, which are mainly breeding in the Southern subarea. These females could be suffering from Ah-receptor-related toxic effects, some of which have been related to altered bird reproduction. Finally, a significant negative correlation between p,p′-DDE levels and eggshell thickness (r=−0.469, p<0.001) was observed, with about 17% of eggshell thinning for eggs with p,p′-DDE levels above 100μgg−1lw. The persistence of this degree of thinning over a period of time has been related to population declines in other raptor species.

A preliminary investigation of unintentional POP emissions from thermal wire reclamation at industrial scrap metal recycling parks in China

Thermal wire reclamation is considered to be a potential source of unintentional persistent organic pollutants (unintentional POPs). In this study, unintentional POP concentrations, including PCDD/Fs, dioxin like PCBs (dl-PCBs), polychlorinated naphthalenes (PCNs), hexachlorobenzene (HxCBz) and pentachlorobenzene (PeCBz), were quantified in flue gas and residual ash emissions from thermal wire reclamation at scrap metal dismantling parks in Zhejiang Province, China. The total average TEQ emissions of the investigated unintentional POPs from flue gas and residual ash in two typical scrap metal recycling plants ranged from 13.1 to 48.3ngTEQNm−3 and 0.08 to 2.8ngTEQg−1, respectively. The dominant PCDD/F congeners were OCDD, 1,2,3,4,6,7,8-HpCDD, OCDF and 1,2,3,4,6,7,8-HpCDF, while PCB-126 and PCB-169 were the main contributors to the toxicity of the dl-PCBs. There were clear differences in the distribution dl-PCBs congeners contributing to the TEQ concentrations in the flue gas samples from the two plants. The PCN TEQs were dominated by PCN-66/67 and PCN-73. Although thermal wire reclamation in incinerators has been proposed as an alternative to open burning, there are still considerable environmental risks associated with regulated incinerators, and unintentional POP emissions from thermal wire reclamation sites need to be controlled by local government agencies.

Persistent organic pollutants in sediment from the southern Baltic: risk assessment

The concentrations of organochlorine pesticides, PCBs, and PCDD/Fs were measured in sediment samples collected from the Gulf of Gdańsk, the Gdańsk Deep, the Vistula Lagoon and the off-shore waters in the southern Baltic Sea. The determinations were conducted in the fraction <63 μm. The highest levels of pollutants were found in sediments from the Gulf of Gdańsk and the Gdańsk Deep. In these sediments, concentrations of pp'-DDT and its metabolites (pp'-DDE and pp'-DDD) ranged from 2 to 11 μg kg(-1) dw. Concentrations of HCB were between 0.1 and 1.0 μg kg(-1) dw. Concentrations of the sum of α-, β-, γ-HCH were between 0.3 and 2.58 μg kg(-1) dw. Concentrations of marker PCBs ranged from about 2 to 11 μg kg(-1) dry weight. Total TEQ PCDD/F/dl-PCB values in the studied samples varied between 1 and 18 ng kg(-1) dw. The data were evaluated in terms of ecotoxicological criteria based on the environmental impact of the pollutant effects. Our research indicated that in the sediment from the southern Baltic Sea, the PCDD/F and PCBs occurred at concentrations which could be dangerous to marine organisms.

In VitroTransactivation Potencies of Black-Footed Albatross (Phoebastria nigripes) AHR1 and AHR2 by Dioxins To Predict CYP1A Expression in the Wild Population

Our previous studies have detected high levels of dioxins and related compounds (DRCs) including polychlorinated dibenzo-p-dioxins (PCDDs), furans (PCDFs), and coplanar PCBs (Co-PCBs) in the black-footed albatross (BFA), Phoebastria nigripes, from the North Pacific region. We have also cloned two aryl hydrocarbon receptors, AHR1 and AHR2, of the BFA. To evaluate the sensitivity to DRCs in the BFA and to assess the status of cytochrome P450 1A (CYP1A) induction in the wild population, this study investigated the mRNA expression levels of BFA AHR1 and AHR2 and also the transactivation potencies of each AHR by 15 selected DRC congeners. Quantitative real-time PCR of BFA AHR mRNAs showed that hepatic AHR1 is more highly expressed than AHR2. Transactivation by graded concentrations of individual DRCs was measured in COS-7 cells, where BFA AHR1 or AHR2 was transiently transfected. For congeners that exhibited AHR-mediated dose-dependent activities, 50% effective concentration (EC(50)) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) relative potencies (REPs) were estimated. Based on the estimates of the REPs, TCDD induction equivalency factors (IEFs) were determined. For BFA AHR1, PeCDF was equipotent to TCDD, but other congeners exhibited lower IEFs. For BFA AHR2, PCDD/F congeners except OCDD/F showed IEFs ≥ 1.0. Using BFA AHR1- or AHR2-IEFs and hepatic concentrations of DRCs in North Pacific BFAs, TCDD induction equivalents (IEQs) were calculated. We further constructed nonlinear regression models on the relationships between BFA AHR1- or AHR2-IEF derived total IEQ or WHO-TEF derived total TEQ and ethoxyresorufin-O-deethylase activity (EROD) in the liver of wild BFAs. The results indicated that the relationships of BFA AHR1- and AHR2-based IEQs and EROD were predictable from BFA AHR1- and AHR2-mediated transactivation by TCDD, respectively. Collectively, these results suggest that the in vitro assay incorporating the AHR of species of concern would be a useful tool to predict the sensitivity to DRCs in the species and CYP1A induction in the wild population.

Transfer and uptake of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and polychlorinated biphenyls (PCBs) into meat and organs of indoor and outdoor reared pigs

This study was designed to investigate how and to what extent PCDD/Fs and PCBs are transmitted from exposure sources to porcine muscle and other tissues derived from pigs. The experimental approach involved two longitudinal studies in which indoor and outdoor pigs were reared to market readiness using typical animal husbandry practices; closely matched samples of soil, feed, bedding, meat, etc. were collected and analysed for PCDD/Fs and PCBs. The total PCDD/F + PCB WHO-TEQs in pig liver were much higher than in meat and kidney samples from the same animals and exceeded the current relevant European Union maximum limits (6 ng PCDD/F-TEQ kg−1 fat). Liver samples were also characterised by much lower PCB contributions to the total TEQ than for the corresponding meat and kidney samples, and by a predominance of many of the hepta- and octa-substituted PCDD/Fs. At ages approaching market readiness, TEQ values in meat samples from outdoor pigs tended to be slightly higher than those from comparable ages in the indoor programme, possibly due to additional intake from soil. Biotransfer factors (BTFs) were derived for each of the 39 PCDD/F and PCB congeners measured. Interpretation of the findings focused particularly on trends in four selected congeners, namely: 2,3,7,8-TCDD, 2,3,4,7,8-PeCDF, PCB 153 and PCB 169. Increases in the BTF for PCB 169 in the pig-rearing programmes were noticed when the diet changed from being dominated by sow's milk to feed. Much higher transfer factors for many of the more heavily chlorinated PCDD/Fs (e.g. 2,3,4,7,8-PeCDF) were found in liver compared with meat or kidney samples from the same animals. Soil consistently accounted for at least 30% of input for many hexa- or higher chlorinated PCDD/Fs, while it rarely representing more than 10% of the total intake.

Maternal exposure to high levels of dioxins in relation to birth weight in women affected by Yusho disease

Background Studies on the association of maternal exposure to polychlorinated dibenzo- p-dioxin (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) with decreased birth weight in humans have produced conflicting results. In Japan in 1968, an accidental human exposure to rice oil contaminated with PCDDs, PCDFs, and PCBs, led to the development of Yusho disease. Objective The Yusho cohort was used to evaluate the effect of maternal exposure to PCDDs, PCDFs, and PCBs on birth weight. Methods Blood samples, obtained from 101 Yusho women (190 births) who gave birth after exposure, were analyzed for congeners of seven PCDDs, ten PCDFs, and four non- ortho PCBs. Results Total PCDD TEQ (adjusted beta = − 161.9 g; 95% CI, −265.3 to − 58.6), total PCDF TEQ (adjusted beta = − 105.9 g; 95% CI, −179.5 to − 32.2), and total non- ortho PCBs (adjusted beta = − 178.4 g; 95% CI, −318.3 to − 38.5) levels were inversely associated with birth weight. Significant inverse associations with birth weight were also found for total PCDD TEQ, total PCDF TEQ, and total non- ortho PCB TEQ levels among male, but not female, infants. Significant inverse associations with birth weight were also found for nine congeners among all infants; the adjusted beta coefficients were largest for 1,2,3,6,7,8-HxCDD and smallest for 2,3,4,7,8-PeCDF. Conclusion In the setting of exposure to high levels of dioxins, maternal blood levels of PCDDs, PCDFs and PCBs are associated with lower birth weight in Yusho patients. The association exhibited gender-specific differences, as male infants are more susceptible than females to growth restriction induced by in utero dioxin exposures.

GC-MS ultra trace analysis of dioxins produced through hydrothermal gasification of biowastes

Hydrogen gas and the valuable material hydroxylapatite have successfully been produced from biomass wastes by hydrothermal gasification. However, it was expected that toxic compounds might be produced through the reaction. It was therefore important to clarify whether toxic compounds were synthesized in hydrothermal gasification of biowastes since dioxins are categorized among the most toxic compounds for humans. This is particularly true of biomass wastes containing hetero-atoms in organic matrices. In this study, formation of the dioxins polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and certain dioxin-like polychlorinated biphenyls (PCBs) were examined. Chicken manure and cattle manure were tested as real biowastes for hydrothermal gasification and the produced compounds in the liquid and solid phases were analyzed for detection of dioxins by gas chromatography/mass spectrometry (GC/MS). The total toxic equivalent quantities (the total TEQ) of dioxins produced by the hydrothermal gasification were found to be much lower than regulation levels in Japan require and therefore the products require no additional post treatments.

Levels and trends of PCDD/Fs and PCBs in camel milk (Camelus bactrianus and Camelus dromedarius) from Kazakhstan

To date, despite the fact it represents a very important part of the national dairy production, no data are available concerning the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in camel milk from the Republic of Kazakhstan. Selected PCDDs, PCDFs, and PCBs were measured in pools of milk from camels (n=15) located in various places of Kazakhstan (Almaty, Atyrau, Aralsk, Shymkent) and sampled at two different seasons for two different species (Camelus bactrianus and Camelus dromedarius). Non-dioxin-like (NDL-)PCB concentrations (6.3±2.7ngg−1 fat, median 5.1ngg−1 fat, range 0.6–17.4ngg−1 fat) were far below the maximum value of 40ngg−1 fat proposed by the EU. Dioxin-like (DL-)PCB concentrations (1.7±0.7ngg−1 fat, median 1.5ngg−1 fat, range 0.3–4.2ngg−1 fat) and the NDL-PCB to DL-PCB ratio (4.3) were similar to what is reported in EU for cow-based dairy products. PCB 52 and PCB 101 appeared to be proportionally more present in Kazakh camel milk samples (>60% of the sum of the 6 indicator NDL-PCBs) than in European cow milk samples (<10% of the sum of the 6 indicator NDL-PCBs), indicating possible differences in the route of exposure to PCBs in Kazakhstan. PCB 105 and PCB 118 appeared to be present at higher concentrations in camel milk (>80% of the sum of the 12 DL-PCBs). PCB 105, PCB 118 and PCB 156 were the major congeners for DL-PCBs, accounting for 92% of the sum of concentrations of DL-PCBs (88% for Belgian cows). In terms of TEQ, PCB 126 and PCB 118 are the major contributors and represent, respectively, 80% and 14% of the DL-PCB TEQWHO05 concentrations. No significant interracial or geographical trends were observed for NDL- and DL-PCB profiles. However, concentrations of all DL-PCBs appeared to be significantly higher for samples collected in Atyrau region. 2,3,7,8-TCDD level (mean 0.08±0.07pgg−1 fat, median 0.08pgg−1 fat, range 0.00–0.18pgg−1 fat, 60%>LOQs) were very low for all samples and 2,3,4,7,8-PeCDF was the major contributor (27%) to the PCDD/F TEQWHO05. Considering the total TEQWHO05 (sum of DL-PCBs and PCDD/Fs), DL-PCB and PCDD/F contributed for 73% and 27%, respectively. A decrease of only 1% of the total TEQ was observed when using the TEFWHO05 scale instead of the TEFWHO98 scale. Two samples collected in the region of Atyrau exceeded the EU maximum level value of 6.00pg TEQWHO98g−1 fat (6.4pg TEQWHO05g−1 fat and 6.9pg TEQWHO05g−1 fat). Both samples exceeded the EU action level for the sum of DL-PCBs. Based on the fact that camel milk is used to prepare popular traditional fermented drinks like shubat, this suggests that the human exposure in the Caspian Sea region of Atyrau should be expected to be higher than in the other regions studied here.

Sources of PCDD/Fs, non-ortho PCBs and PAHs in sediments of high and low impacted transboundary rivers (Belgium–France)

PAHs, PCDD/Fs and non-ortho PCBs have been assessed in Yser and Upper-Scheldt river sediments. Higher contamination levels were observed in the Upper-Scheldt sediments: maximum concentrations for the 16 US-EPA PAHs, PCDD/Fs and non-ortho PCBs respectively amount to 8.9 mg kg −1, 12 ng TEQ kg −1 and 5.1 ng TEQ kg −1. Diagnostic PAH ratios in sediments and atmospheric samples suggest that the PAH compounds are from pyrolytic origin, more specifically combustion processes. The huge consumption of coal in cokes-ovens and smelters and its use for house-heating in Northern France, although decreasing during the last decades, are in support of that suggestion. PCDD/F fingerprints in sediments and deposition material indicate that OCDD is the dominant congener. In addition use of pentachlorophenol (PCP) in the past led to a minor contribution of PCDD/Fs in our sediment samples. Non-ortho PCBs form a substantial fraction of the total TEQ concentrations observed in the sediments. Since the 1980s and 1990s a substantial reduction of the PCDD/F sediment concentrations is observed, but this is not the case for the PAHs.

Determination of PCBs, PCDDs and PCDFs in insulating oil samples from stored Chinese electrical capacitors by HRGC/HRMS

Homologue and congener profiles of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in commercial PCBs formulations are key information for the source identification of PCBs contamination as well as for the risk assessment caused by potential exposure. The isotope dilution technology in combination with high resolution gas chromatography–high resolution mass spectrometry (HRGC/HRMS) has made the accurate determination of such profiles possible. So far, various commercial PCB formulations except Chinese products have been successfully determined. Two PCBs containing insulating oil samples from stored Chinese electrical capacitors have been determined with the same methodology for comparability. The total concentration PCBs in two oil samples were 790 000 μg g −1 and 720 000 μg g −1, respectively. TriCBs, TetraCBs, and DiCBs were found to be most abundant. Concentration of dioxins contamination in two samples is 650–670 ngTEQ g −1, of which 69–71 ngTEQ g −1 from PCDD/Fs with the predominant congeners of 1,2,7,8-TeCDF; 2,3,7,8-TeCDF; 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDF. The contributions of DL-PCBs in total TEQ in both samples were more than 85%. The dioxin-like toxicity in insulating oils contained in electrical capacitors could be considered receive attention as an important dioxins source if such wastes are not managed in an environmentally sound manner.