A comparison of TEQ contributions from PCDDs,PCDFs and dioxin-like PCBs in sewage sludges from Catalonia,Spain

Eight sewage sludges from rural, urban and industrial wastewater treatment plants (WWTPs) in Catalonia (Spain) were analysed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) to determine the present levels of contamination. A method based on an automated cleanup system followed by an isotope-dilution high-resolution mass spectrometric analysis was employed. Total toxicity equivalent (WHO-TEQ) values were calculated using the toxicity equivalent factors (WHO-TEFs) proposed by WHO for dioxin-like PCBs, PCDDs and PCDFs. The WHO-TEQ(PCDD/F) values for these samples ranged from 4.9 to 20.8 pg/g dry weight (d.w.), with a mean value of 9.3 pg/g d.w., whereas WHO-TEQ(PCB) levels ranged between 1.9 and 6.6 pg/g d.w., with a mean value of 4.2 pg/g d.w. The WHO-TEQ(PCB) contribution varied from 13% to 50%, suggesting that PCB contribution on the toxicity of the samples must be taken into account. Moreover, these contemporary PCDD, PCDF and PCB concentrations were compared with previous data obtained from sewage sludge samples collected during the 80s. Our findings show that contemporary PCDD, PCDF and PCB levels have declined since the 80s.     

Levels of PCDDs, PCDFs, and PCBs in the blood of the non-occupationally exposed residents living in the vicinity of a chemical plant in the Czech Republic

In 2003, concentrations of altogether 17 PCDD/Fs congeners and 12 non-ortho and mono-ortho dioxin-like PCBs were measured in the blood of 60 randomly selected adults who lived in three settlements surrounding a chemical plant that had been producing chlorinated herbicides (mainly HCHs, HCB, pentachlorophenole, 2,4,5-T) in the 1960's; subjects consuming home-produced animal foods were chosen. Twenty blood donors with similar characteristics from the locality with about 80 km distance were used as control subjects. The factors that influenced the dioxin levels were investigated on the basis of a questionnaire. The aim of our study was to find out whether the residents living in the surroundings of the chemical plant are at a greater exposure risk than the controls. To calculate TEQ values, WHO-TEFs were used. The concentrations of four PCDD and six PCDF congeners were below the LOD in more than 50% of samples. Significantly higher WHO-TEQ levels (p<0.05) were found for PCDDs, PCDFs, or PCBs in all three followed up groups compared with controls. The geometric means of the total TEQ values for PCDD/F/PCBs were 43.8, 50.2, and 40.0 pg/g fat compared to 23.2 pg/g fat in the control. The percentages of TEQ due to the measured congeners in exposed groups were 9-10.3% for PCDDs, 20.5-26.9% for PCDFs, 19.2-23.1% for coplanar and 43.6-47.2% for mono-ortho PCBs. In control, the percentage of TEQ was 11.6, 26.7, 24.1, and 37.5%. PCBs, predominantly PCB156, followed by PCB126 contributed 60 to 70% of the total TEQ value. Positive correlation of the PCDD/PCDF/PCB blood levels with age and with consumption of locally produced eggs was found.     

Development and validation of a method for analysis of "dioxin-like" PCBs in environmental samples from the steel industry

A method, previously used for determination of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), has been modified for quantitative analysis of "dioxin-like" polychlorobiphenyls (PCBs) in environmental samples from the steel industry. The existing sample clean-up procedure, involving liquid chromatography on multi-layered silica and Florisil columns, has been extended to include a third chromatography stage on a basic alumina stationary phase. The additional clean-up stage is required for PCB analysis in order to eliminate interferences from relatively large concentrations of saturated cyclic and aliphatic hydrocarbons. Samples were analysed for WHO-12 congeners using high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) and standard solutions of the method US EPA 1668A. Replicate analysis of method blanks revealed background contamination for PCBs 118, 105 and 77, which are generally abundant in ambient air. These contaminants were taken into account using a subtraction method. The entire procedure was validated by replicate analysis (N = 3) of a certified reference sediment. The RSD for each WHO-12 congener was below 15%, 13C12-labelled PCB internal standard recoveries were in the range 70-95%. A waste dust sample collected in the electrostatic precipitator of a UK sinter plant was analysed for determination of PCDD/Fs and WHO-12 PCBs and exhibited a PCDD/F I-TEQ of 148.5 +/- 21.2 ngkg(-1) and a WHO-TEQ of 7.2 +/- 1.5 ngkg(-1). WHO-12 congeners contributed only 4.6% to the overall TEQ and PCB 126 was the major congener contributing to the WHO-TEQ (96%). The contribution to the overall TEQ of the waste dust sample was mainly attributed to PCDF followed by PCDD, which accounted for 86.6% and 8.7% to the overall TEQ, respectively.     

Polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls levels in human breast milk from different regions of Turkey

Human breast milk offers the optimal nutrition for all infants and have been widely used in biomonitoring programs to assess human exposure to lipophylic environmental contaminants such as polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polychlorinated biphenyls (PCB). There are no previous reports from Turkey on chemically determined levels of PCDDs, PCDFs, and PCBs in human breast milk expressed as World Health Organization (WHO) toxic equivalents (TEQ). To get an overview of the levels of these contaminants in Turkish human milk, samples from 51 Turkish women living in the Ankara, İstanbul, Antalya, Kahramanmaraş, and Afyon provinces were analyzed by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) throughout 2007. The mean concentrations of WHO_PCDD/F-TEQ and WHO_PCB-TEQ of all samples from the five regions were 7.5 and 3.1 pg g⁻¹ on a lipid basis, respectively. PCDD/F concentrations ranged between 0.78 and 29.3 pg WHO-TEQ g⁻¹ fat (1.7 and 36.2 pg WHO-TEQ g⁻¹ fat, respectively, including PCB). Of the five studied locations, the lowest levels of ∑TEQs (PCDD/F + PCB) were found in the Afyon (6.8 pg WHO-TEQ g⁻¹ fat) and the highest in the Antalya (15.6 pg WHO-TEQ g⁻¹ fat) province. The results have been discussed in terms of regions and PCDD/F and PCBs for which analyses had been made. The mean levels of PCDD/Fs and PCBs in Turkish human milk are comparable to that found in other countries.     

Concentrations of polybrominated diphenyl ethers, organochlorine compounds and nitro musks in mother's milk from Germany (Bavaria)

The aim of this study was to determine a new spectrum of substances that will be selected for future breast milk monitoring in Bavaria, Germany. Up to now, the analysis of breast milk in Bavaria was limited to selected organochlorine pesticides (OCP) and polychlorinated biphenyls (PCB). Information on background levels of toxicologically interesting substances, such as dioxins and dioxin-like polychlorinated biphenyls (dl-PCB) or on flame retardants, such as polybrominated diphenyl ethers (PBDE) are very limited or not available for Bavaria. We present here levels on OCP, some nitro musks, indicator PCB, polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and dl-PCB concentrations in breast milk collected at 12 weeks post-partum of 43 primiparous mothers living in Bavaria. The average concentrations of PCDD, PCDF and dl-PCB were 4.98, 4.93 and 9.92 pg WHO-TEQ g(-1) lipid, respectively. The mean contribution of PCDD, PCDF, non-ortho and mono-ortho PCB to the total WHO-TEQ is consistently about 25% each. Furthermore the concentration on PBDE in breast milk at two sampling points, 12 weeks and 16 weeks after delivery, were determined. Overall, 19 PBDE congeners were analysed, however the level of 12 PBDE congeners were below the limit of detection. BDE-153 and BDE-47 were the predominant congeners accounting for about 66% of the total PBDE. The means of the total concentrations of PBDE (five congeners) at the first and second sampling point were 1.90 and 2.03 ng g(-1) lipid, respectively. Based on our results the overall concentrations of the analysed substances in milk samples from Bavaria are consistent with the levels of breast milk samples of other European countries reflecting the low background body burden of these compounds.     

PCB and dioxin-like PCB in indoor air of public buildings contaminated with different PCB sources--deriving toxicity equivalent concentrations from standard PCB congeners

Data on dioxin-like PCB in indoor air of buildings with PCB-containing materials and on possible correlation between toxicity equivalent concentrations (TEQ) and levels of non-dioxin-like standard PCB is sparse. As part of a larger survey on indoor-air contamination with PCB, the connection between the concentration of standard PCB congeners and the dioxin-like toxicity expressed as TEQ was investigated. Indoor air samples (n=8) were collected in four public buildings with known PCB sources and total PCB levels in the range from 715 to 2250 ng/m3 and analyzed for the six non-dioxin-like standard PCB (congeners 28, 52, 101, 138, 153, 180), the twelve dioxin-like PCB congeners according to WHO and the 17 2,3,7,8-substituted PCDD/PCDF congeners. In three buildings where PCB were used as flame retardant coatings of acoustic ceiling tiles, PCB 101 had the maximum level among the six standard PCB, while in the building with permanent elastic sealants as PCB source, congeners 28 and 52 dominated the pattern by far. In the case of permanent elastic sealants as PCB source (n=3) a total PCB concentration of 1000 ng/m3 corresponded to a total TEQ level of 0.3-0.6 pg/m3. In contrast, in rooms with acoustic ceiling tiles as PCB source, 1.8-4.7 pg TEQ/m3 per 1000 ng total PCB/m3 were found. Linear regression analysis between PCB and TEQ indicated that PCB 118 might be used to calculate the total TEQ of dioxin-like PCB and PCDD/PCDF. By means of such a correlation it is possible to estimate TEQ by extrapolation from the results of less sophisticated analytical methods. It is tentatively recommended to use PCB 118 for screening purposes or re-evaluation of standard PCB indoor-air measurements. If only the six non-dioxin-like PCB standard congeners are available, a regression algorithm using the sum of PCB 101, 138, 153 and 180 might be used instead.     

HCB,PCB, PCDD and PCDF emissions from ships

Since current estimates of hexachlorobenzene (HCB), polychlorinated biphenyls (PCB), dioxins (PCDD) and furans (PCDF) from ships are based on a relatively limited and old data set, an update of these emission factors has been outlined as a target towards improved Swedish emission inventories. Consequently, a comprehensive study was undertaken focusing on these emissions from three different ships during December 2003 to March 2004. Analyses were performed on 12 exhaust samples, three fuel oil samples and three lubricating oil samples from a representative selection of diesel engine models, fuel types and during different “real-world” operating conditions.The determined emissions corresponded reasonably well with previous measurements. The data suggest however that previous PCDD/PCDF emission factors are somewhat higher than those measured here. As expected the greatest emissions were observed during main engine start-up periods and for engines using heavier fuel oils. Total emissions for 2002, using revised emission factors, have been calculated based on Swedish sold marine fuels and also for geographical areas of national importance. In terms of their toxic equivalence (WHO-TEQ), the PCDD/PCDF emissions from ships using Swedish fuels are small (0.37–0.85 g TEQ) in comparison to recent estimates for the national total (ca. 45 g TEQ). Emissions from other land-based diesel engines (road vehicles, off-road machinery, military vehicles and locomotives) are estimated to contribute a further 0.18–0.42 g TEQ. Similarly, HCB and PCB emissions from these sources are small compared to 1995 national emission inventories.     

Atmospheric deposition of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in the Kanto Region, Japan

The atmospheric bulk (dry and wet) deposition of dioxins was investigated at four locations (Tokyo, Yokohama, Tsukuba, and Tanzawa) in the Kanto region (in Japan) over one year using a stainless-steel pot. Annual average polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) deposition fluxes were estimated to be from 450 to 1300 ng/m2/yr, and the annual average TEQ fluxes from 5.7 to 17 ng-TEQ/m2/yr at the four locations. The PCDD/PCDF deposition flux was higher in winter than in summer. The deposition flux could be related to ambient temperature, particularly for less chlorinated PCDDs/PCDFs, while the deposition flux is not necessarily related to the amount of precipitation. The PCDD/PCDF deposition flux increased as the particle deposition flux increased, for the winter samples. Based on the ratio of the PCDD/PCDF deposition fluxes to the particle deposition fluxes, the contribution of the reentrainment of soil particles to the TEQ of PCDD/PCDF deposition was considered to be negligible in this region. Based on the air concentrations monitored near our deposition sampling points by the municipalities, the ratio of the annual deposition flux to the annual average air concentration was roughly estimated to be 0.082 cm/s. The range of deposition flux in the Kanto region was estimated to be from 1.5 to 31 (median: 9.8) ng-TEQ/m2/yr based on the range of air concentration data measured by the municipalities. The total annual deposition flux in the entire Kanto region was estimated to range from 50 to 900 g-TEQ/yr (median 320 g-TEQ/yr). This estimated flux was of the same order as the sum of estimated emissions from municipal solid waste incinerators and industrial waste incinerators in the Kanto region. The contributions of dioxin-like PCBs in Yokohama, Tsukuba, and Tanzawa depositions were less than 10% of the total TEQ; however, in Tokyo it was almost equal to or more than 50%.     

Biomonitoring of persistent organochlorine pesticides, PCDD/PCDFs and dioxin-like PCBs in blood of children from South West Germany (Baden-Wuerttemberg) from 1993 to 2003

In the context of a monitoring program, persistent organic pollutants (POPs) were quantified in the blood of 10 year old children at four different demographic regions in Baden-Wuerttemberg, a highly industrialised federal state in South West Germany. DDE, HCB, PCB 138, PCB 153 and PCB 180 were measured in 1996/1997, 1998/1999, 2000/2001 and 2002/2003 in individual samples of about 400 children per year. PCDD/PCDFs and some relevant coplanar PCBs were determined in pooled samples from children in seven cycles from 1993 to 2003. Blood concentrations of the investigated compounds decreased in that time period by a factor of 2-4 with the exception of most PCDFs. The concentrations of POPs in the blood of the children were distinctly lower than the concentrations reported for adults. Breast feeding was associated with about 30% higher median concentrations of DDE, HCB, PCBs and a 30% increase for mean PCDD/PCDF concentrations. Concerning demographic differences, significant lower concentrations of HCB, PCBs and PCDD/PCDFs could be seen in children from Mannheim compared to the region of Aulendorf. About 10-20% higher concentrations were found in boys compared to girls for HCB, indicator PCBs and PCDD/PCDFs. The pattern of non-ortho and mono-ortho PCBs in the blood of children was similar to the pattern reported for mother's milk, and PCB 126 and PCB 156 contributed about 70% to the toxicity of dioxin-like PCBs and about one-third to total TEQ including PCDD/PCDFs.     

Levels of PCDDs, PCDFs and PCBs in Belgian and international fast food samples

Congener-specific analyses of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were performed on twenty-eight non-pooled fast food samples collected in Belgium, Switzerland, Czech Republic, United States of America and Australia. PCDD/F and PCB concentrations for the four investigated types of meals were very low. PCDD/F values ranged from non-detected to 1.40 pg WHO-TEQ/g fat and from 0.79 to 2.08 pg WHO-TEQ/g fat for lower and upper bound, respectively. Major contributors to the PCDD/F TEQ were 1,2,3,4,7,8-HxCDD, 1,2,3,6,7,8-HxCDD, 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF. The relative contribution of PCBs to the total TEQ was 68%. For adults, an average estimated intake was 6.7 pg WHO-TEQ/kg bw/month, including consumption of all types of analyzed meals, representing 9.5% of the PTMI. For child, a value of 14.5 pg WHO-TEQ/kg bw/month was obtained, representing 20.6% of the PTMI.     

PCDD/F and dioxin-like PCB in Hong Kong air in relation to their regional transport in the Pearl River Delta region

PCDD/F and dioxin-like PCB were measured in 142 air samples of Hong Kong. The annual average PCDD/F and dioxin-like PCB concentrations obtained for Hong Kong air at Tap Mun (PCDD/F: 1724+/-1984; dioxin-like PCB: 1572+/-1170 fg m(-3)), Yuen Long (PCDD/F: 2927+/-2695; dioxin-like PCB: 4331+/-1962 fg m(-3)) and Tsuen Wan (PCDD/F: 1875+/-1502; dioxin-like PCB: 2972+/-1510 fg m(-3)) from January 2004 to March 2005 were comparable to other urban centers around the world and were within the Japanese and USA ambient air quality guidelines. A clear seasonal pattern was observed for PCDD/F, generally with a 50-60 times higher air concentration in winter when background northerly wind was weaker and land-sea breeze prevailed, resulting in regional transport; and a lower concentration in summer, due to the inflow of clean oceanic southeasterly wind from the South China Sea. A higher WHO-TEQ value of dioxin-like PCB (mainly attributed to the relatively higher WHO-TEQ value of PCB 126) in Yuen Long during winter, compared with other months, could also be related to the regional transport by the winter monsoon wind and the low mixing height in winter. Spatially, air concentrations of PCDD/F and dioxin-like PCB demonstrated a west-to-east gradient (with Yuen Long>Tsuen Wan>Tap Mun). It is suggested that PCDD/F and dioxin-like PCB were transported into the western airshed of Hong Kong from the Pearl River Delta by land-sea breeze circulation and confined to the northwestern part, due to the blocking effect of the northwestern airshed in Hong Kong.     

Concentration of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like PCBs in human adipose tissue from Turkish men

There is no previous report from Turkey on chemically determined polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) in human tissues expressed as World Health Organization (WHO) toxic equivalents (TEQs). The objective of this study was to determine the occurrence of PCDDs/Fs, and dioxin-like PCBs in the general adult Turkish population. For this reason we measured adipose tissue concentrations of PCDDs/Fs and dioxin-like PCBs in 23 Turkish men living in Ankara,Turkey in 2004. PCDD/F concentrations ranged between 3.2 and 19.7 pg WHO-TEQ/g fat (5.34 and 42.7 WHO-TEQ/g fat, respectively, including dioxin-like PCBs). The mean concentrations of WHO(PCDD/F)-TEQ and WHO(PCB)-TEQ were 9.2 and 6.67 pg/g on a lipid basis , respectively. Samples were analyzed for PCDD/F and twelve dioxin-like PCB congeners using high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). This study is very important since it is the first report on PCDDs/Fs and dioxin-like PCB contamination in human adipose tissue from Turkey.     

Dietary intake of PCDDs, PCDFs and dioxin-like PCBs, due to the consumption of various marine organisms from Korea

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) residues were measured in 70 marine organisms (40 species) from Korean coastal waters. The PCDD/Fs residues in the organisms varied from 0.02 to 4.39 pg WHO-TEQ/g wet weight and the DL-PCBs residues varied from 0.008 to 6.0 pg WHO-TEQ/g wet weight. The levels in fish from Korean coastal waters were comparable to those found in other countries. Comparing organism groups, the highest PCDD/Fs and DL-PCBs residues were recorded in crustaceans, followed by fish, cephalopods, bivalves and gastropods. Although the congener distributions of PCDD/Fs and DL-PCBs in the organism groups were different, the dominant contributors to the total TEQ concentrations in all groups were 2,3,4,7,8-pentachlorinated dibenzofuran (PeCDF), 1,2,3,7,8-pentachlorinated dibenzo-p-dioxin (PeCDD) and PCB 126. The dietary intake of PCDD/Fs and DL-PCBs from the consumption of marine organisms in Korea was estimated to be 0.68 pg WHO-TEQ/kg bodyweight/day. The contribution of DL-PCBs to the total dietary intake from all organisms groups averaged 60%. The relative contribution of each organism group to the total dietary intake was, in descending order: fish, crustaceans, cephalopods, bivalves and gastropods. The current dietary intake was lower than those in countries with a similar dietary pattern to Korea, but higher than those in countries with smaller quantities of seafood consumption.     

PCDD/Fs and PCBs in butter samples from new European Union member states and a candidate country: analytical quality control, results and certain PCB-specific aspects

Milk and milk products have shown to be good indicator samples for the contamination of persistent organic pollutants (POPs) along the food chain. To gather information on whether exposure to dioxins and PCBs might cause a problem in countries about to join the European Union in 2004 or later, a study for evaluation of dioxin and levels of PCBs in 16 butter samples from eight countries (Cyprus, Czech Republic, Estonia, Lithuania, Poland, Romania, Slovenia and Slovakia) was performed. Comprehensive quality assurance/quality control (QA/QC) was requested. For this, eight quality control samples were included (in comparison to long-term mean, mean recovery for WHO-PCDD/F-TEQ of 97.9% with a CV of 3.0%, mean recovery for WHO-PCB-TEQ of 100.4% with a CV of 3.3%). Additionally, all butter samples were run as duplicates resulting in a confidence region of 95% statistical certainty of 4.6% for WHO-PCDD/F-TEQ and of 3.5% for WHO-PCB-TEQ. All samples except one from Romania were in the range of 0.21-0.59 pg WHO-PCDD/F-TEQ/g fat (upper bound), all samples except one from Romania and one from Estonia in the range of 0.32-0.82 pg WHO-PCB-TEQ/g fat (upper bound) and all samples except one from Romania and one from Estonia in the range of 0.57-1.23 pg sum WHO-TEQ/g fat (upper bound). The maximum values were found in samples from Romania (0.98 pg WHO-PCDD/F-TEQ/g fat; 1.75 pg WHO-PCB-TEQ/g fat) and Estonia (0.26 pg WHO-PCDD/F-TEQ/g fat; 1.62 pg WHO-PCB-TEQ/g fat). As a conclusion, all samples except one from Romania and one from Estonia were in the range of the actual low background contamination for PCDD/F and dioxin-like PCBs. The samples with elevated concentrations were below the EU action and maximum levels which have been valid since 2002, or will be applied from November 2006. In all samples except in one from Estonia, the contribution of dioxin-like PCBs to sum WHO-TEQ was 47-68% which reflects the usual range in Europe. In one sample from Estonia this contribution was 86% which points to a particular yet unknown PCB source. Thirty eight PCB congeners were determined allowing a detailed discussion of the relative contribution of individual congeners to the total PCB concentration. Correlation between PCB 153 and WHO-PCB-TEQ varied considerably between samples from different countries. Major tetra- or pentachlorinated mono-ortho PCBs without assigned TEFs were PCBs 60, 66, 74, and 110.     

Dioxin and dioxin-like PCB exposure of non-breastfed Dutch infants

The exposure of humans to PCDD/Fs (polychlorinated dibenzo-p-dioxins and dibenzofurans) and dioxin-like PCBs (dl-PCBs, i.e. polychlorinated non-ortho and mono-ortho biphenyls) occurs predominantly via the intake of food. Young children have a relatively high intake of these substances, due to their high food consumption per kilogram body weight. As the exposure of non-breastfed infants to these compounds has not been assessed before in The Netherlands, we studied the dietary intake of 17 PCDD/Fs and 11 dioxin-like PCBs in 188 Dutch non-breastfed infants between 4 and 13 months. The food intake of the infants was assessed by a 2-d food record. From these data PCDD/F and dioxin-like PCB intake was calculated using PCDD/F and dioxin-like PCB concentrations of food products sampled in 1998/1999 in The Netherlands. The long-term PCDD/F and dioxin-like PCB exposure of the infants was calculated using the statistical exposure model (STEM). For infants of 5 months the chronic exposure to PCDD/F and dioxin-like PCB was 1.1pg WHO-TEQ (toxic equivalents) per kilogram body weight (bw) per day (95th percentile: 1.7pg WHO-TEQ/kg bwxd), which mainly originated from infant formula and vegetables and increased to 2.3pg WHO-TEQ/kg bwxd (95th percentile 3.7pg WHO-TEQ/kg bwxd) for infants just over 1 year old eating the same food as their parents. The percentage of formula-fed infants with an exposure exceeding the TDI of 2pg WHO-TEQ/kg bwxd was 5% at 5 months, 49% at 9 months and 64% at 12 months.     

Determination of PCDD/Fs and dioxin-like PCBs in fish oils for feed ingredients by congener-specific chemical analysis and CALUX bioassay

The present research was intended to determine the suitability of the CALUX assay as a screening method for dioxins in fish oil used as a feed ingredient in Japan. Alteration of TEQ in fish oil according to newly proposed toxic equivalency factors (TEF) is also discussed. In the analysis, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in 41 fish oil samples were determined by using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) and CALUX bioassay. The mean TEQ values derived from 1998 WHO-TEF of PCDD/Fs and DL-PCBs were 2.6 and 9.9 pg g(-1) (ww), respectively. The levels of TEQ derived from the recently re-evaluated 2005 WHO-TEF were slightly lower than those of the former in both groups. Notably, the contribution of mono-ortho DL-PCBs to total 2005 WHO-TEQ was considerably decreased compared to the case of 1998 WHO-TEQ, resulting from the reduction in its TEF values, while the non-ortho DL-PCBs contribution was increased. The mean TEQ determined by CALUX assay for PCDD/Fs was approximately three times higher, whereas DL-PCBs was approximately two times lower than WHO-TEQ determined by HRGC/HRMS; the sum of PCDD/Fs and DL-PCBs was very similar by both methods. The correlation coefficients of TEQ between the CALUX assay and HRGC/HRMS analysis were 0.84, 0.89, and 0.90 for PCDD/Fs, DL-PCBs, and the sum, respectively. These results suggest that the CALUX assay is a very useful method for the screening of dioxin-related compounds in fish oils.     

A total diet study to estimate PCDD/Fs and dioxin-like PCBs intake from food in Taiwan

Concentrations of 17 dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in total diet study samples of 14 food groups of animal origin from 11 locations in Taiwan, collected in 2003. Pork meat possessed the lowest background concentration level of 0.058 pg WHO-TEQ(PCDD/Fs+dl-PCBs)/g fresh weight. The dl-PCBs contribution were 31%, 59%, 36%, 46%, and 13% for meat and meat products, muscle meat of fish, milk and dairy products, fat and oil, and egg, respectively. The estimated monthly intake (EMI) was 44.7 and 39.5 pg WHO-TEQ(PCDD/Fs+dl-PCBs)/kg b.w./month for a male and female adult weighing 64.8 kg and 56.3 kg, respectively. Muscle meat of fish contributes 46% to the mean EMI. Factors affecting the EMI, in order of increasing importance are analytical method uncertainty, sample compositional difference, and food consumption data. In addition to the continuous efforts to identify and reduce the source of PCDD/Fs and dl-PCBs releases into the environment and the food-chain, the practice of a healthy dietary habit, i.e., eating foods of lower TEQ levels, was suggested to effectively reduce human exposure to PCDD/Fs and dl-PCBs.     

Levels and congener distributions of PCDDs,PCDFs and non-ortho PCBs in Belgian foodstuffs--assessment of dietary intake

Congener-specific analyses of 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs) and 4 non-ortho (coplanar) polychlorinated biphenyls (cPCBs) were performed on 197 foodstuffs samples of animal origin from Belgium during years 2000 and 2001. All investigated matrices (except horse) present background levels lower than the Belgian non-commercialization value of 5 pg TEQ/g fat. Pork was the meat containing the lowest concentration of both PCDD/Fs and cPCBs. The mean background concentration of 2,3,7,8-TCDD toxicity equivalent in milk was 1.1 pg/g of fat, with a congener distribution typical of non-contaminated milk. The relative contribution of 2,3,7,8-TCDD, 2,3,7,8-TCDF, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF to the PCDD/Fs TEQ was 85+/-7.9% for all investigated matrices. The cPCBs contribution to the total TEQ was 47+/-19.0% for products of terrestrial species and 69+/-20.0% for aquatic species. Once the contribution of cPCBs was added to the TEQ, few foodstuffs such as horse, sheep, beef, eggs and cheese presented levels above the future European guidelines that currently only include PCDD/Fs but will be re-evaluated later in order to include 'dioxin-like' PCBs. Based on levels measured in the samples, the estimation of the dietary intake was 65.3 pg WHO-TEQ/day for PCDD/Fs only (1.00 pg WHO-TEQ/kg bw/day, for a 65 kg person) and 132.9 pg WHO-TEQ/day if cPCBs were included (2.04 pg WHO-TEQ/kg bw/day, for a 65 kg person). Meat (mainly beef), dairy products, and fish each account for roughly one third of the intake.     

Organochlorine compounds (PCBs, PCDDs and PCDFs) in seafish and seafood from the Spanish Atlantic Southwest Coast

Concentrations and congener specific profiles of PCDD/Fs and PCBs were determined in edible fish and seafood species from the Coast of Huelva, in the Spanish southwest Atlantic coast. Five fish species, namely wegde sole (Dicologoglossa cuneata), common sole (Solea vulgaris), white seabream (Diplodus sargus), sardine (Sardina pilchardus), angler fish (Lophius piscatorius), two shellfish species (Donax trunculus and Chamelea gallina), common cuttlefish (Sepia officinalis) and prawns (Parapenaeus longirostris), frequently found and consumed in the area were analysed. Concentrations ranged from 861 to 23787pg/g wet weight for total PCBs, while 2,3,7,8-PCDD/Fs showed concentrations ranging from 0.2 to 1.18pg/g wet weight. WHO-TEQ concentrations ranged from 0.038 to 0.186pg WHO-TEQ(PCDD/Fs)/g wet weight, values well below the maximum concentrations established by the EU. When non- and mono-ortho PCBs were included the values increased to a maximum of 0.99pg WHO-TEQ(PCDD/Fs+PCBs)/g wet weight. The PCB and PCDD/F accumulation pattern found in the samples analysed showed a distribution typically reported for marine samples, and no remarkable differences were found between species. The PCBs were the ones contributing with the highest percentage to the total TEQ content in most species studied. Concerning the seafood, specially prawns and shellfish, the opposite was observed and PCDD/Fs were found to contribute with a higher percentage than PCBs. The congener specific contribution to the TEQ showed PCB 126 followed by 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF as the most abundant ones.     

PCDD/F and "Dioxin-like" PCB emissions from iron ore sintering plants in the UK

Investigations have been carried out at the three Corus UK sinter plants over the period 2002-2004 to characterise the emissions of both 2,3,7,8-PCDD/Fs and WHO-12 PCBs, to estimate annual mass releases of these organic micro-pollutants using the I-TEF and WHO-TEF schemes, and to investigate the formation of PCBs in the iron ore sintering process. Results showed that the sintering of iron ore produces a characteristic WHO-12 PCB and PCDD/F congener pattern that is substantially the same for all UK sinter plants. With regard to WHO-12 PCBs, the most abundant congeners were typically PCBs 118 (6-9 ngNm(-3)), 105 (2-4 ngNm(-3)) and 77 (2-3 ngNm(-3)). All other WHO-12 PCBs were also detected at concentrations around 1 ngNm(-3). All sinter plants investigated exhibited very similar TEQ concentrations. WHO-12 PCB emissions were in the range 0.042-0.111 ngWHO-TEQNm(-3), whereas PCDD/F emissions ranged from 0.39 to 1.62 ngWHO-TEQNm(-3). PCDF congeners were the main contributors to the overall TEQ in sintering emissions (ca. 85%). Amongst WHO-12 PCBs, PCB 126 was the only noteworthy contributor to total TEQ (ca. 5-7%), a similar contribution to that from PCDDs. Based on the measurements that Corus UK has undertaken at these three sinter plants, annual mass releases of WHO-12 PCBs and PCDD/Fs have been calculated. For UK sinter plants, a total mass release of 29.5 g WHO-TEQ per annum [WHO-12 PCBs+PCDD/Fs] has been estimated, representing 9% of the total PCDD/F emissions to the UK atmosphere. Measurements were also carried out at a UK sinter plant to determine the windleg emission profile of WHO-12 PCBs. Results showed that WHO-12 PCBs were formed in the same regions of the sinter strand as 2,3,7,8-PCDD/Fs, indicating that there was a strong correlation between the formation of WHO-12 PCBs and PCDD/Fs in the iron ore sintering process.