Pg TEQ Research Articles

Congener specific distribution of polychlorinated dibenzo-p-dioxins and dibenzo-p-furans in ambient air particulates (less than PM10) in Delhi, India

Polychlorinated dibenzo-<em>p</em>-dioxins (PCDDs) and polychlorinated dibenzo-<em>p</em>-furans (PCDFs) are unintentionally formed during inefficient combustions and as a by-product. Due to their resistance to degradation and their toxic effect on health, PCDD/Fs are listed by the Stockholm Convention as persistent organic pollutants (POPs). Once released into the atmosphere, most of them are adsorbed to air particles and transported away from sources in atmosphere. India signed the Stockholm Convention India agreeing thereby to reduce and eliminate the use of POPs. The German agency for Technical Cooperation helped develop facilities for monitoring POPs at a national level in Delhi. This paper presents the data generated during a training assignment for Central Pollution Control Board officials at the German laboratory. Air borne particulate matter (<PM<sub>10</sub>) was collected from 6 different locations in Delhi, India and analyzed in a German laboratory for 17 congeners of PCDD/Fs. The concentrations of ΣPCDD/Fs ranged between 1720-9010 fg m<sup>-3</sup> (mean 5559 fg m<sup>-3</sup>) and their toxic equivalency values ranged from 67 to 460 fg I-toxic equivalent quantities (TEQ) m<sup>-3</sup>, with an average of 239 fg I-TEQ m<sup>-3</sup> which was lower than the ambient air standards. The dominant congeners were octachlorinated dibenzo-p-dioxin (OCDD), octachlorinated dibenzo-p-furans (OCDF), 1,2,3,4,6,7,8-heptachlorinated dibenzo- p-furans, and 1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin. The contributions of individual homologs for ΣPCDDs/Fs I-TEQ was in the order of OCDD (31%)>HCDF (21%)>hexachlorodibenzofurans (13%)=OCDF (13%)> HCDF (12%) and other individual congeners contribute less than 5%. High chlorinated congeners contributed with more than 80% for ΣPCDD/Fs I-TEQ. Rough estimates of tolerable daily intake (TDI) shows low health risk of exposure to ΣPCDD/Fs with inhalation of 0.098 pg I-TEQ kg<sup>1</sup>day<sup>1</sup> for adult and 0.152 pg TEQ kg<sup>-1</sup>day<sup>-1</sup> for children, which is much lower than World Health Organization recommended TDI for dioxins.

Chlorinated and brominated dibenzo-p-dioxins and dibenzofurans in surface sediment from Taihu Lake, China

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in surface sediment samples from Taihu Lake--an important water supply of the Yangtze River Delta, China--were investigated in the present study. Concentrations of PCDD/Fs ranged from 0.91 to 4.8 pg TEQ g(-1) dw (mean: 2.9 pg TEQ g(-1) dw, TEQ: Toxic Equivalent), which were all higher than the threshold effect level established by interim sediment quality guidelines in Canada (0.85 pg TEQ g(-1) dw). The levels of PBDD/Fs ranged from 0.16 to 1.6 pg TEQ g(-1) dw (mean: 0.52 pg TEQ g(-1) dw) and accounted for 5-33% (mean: 14%) of the total PCDD/Fs and PBDD/Fs TEQ. Comparatively, the abundance of sedimentary PCDD/Fs in the three regions (Meiliang Bay, Gonghu Bay, and Xukou Bay) showed a decreasing trend from the inflow region to the outflow region, while no significant difference was observed among their 2,3,7,8-PBDD/Fs levels, which suggested that the sources of PCDD/Fs and PBDD/Fs differed in this area. Principal component analysis suggested that the historical production/usage of pentachlorophenol and sodium pentachlorophenate was the dominant source of PCDD/Fs in the sediment of these regions. Although the specific sources of PBDD/Fs in the sediment of Taihu Lake were unclear, it was suspected to be due to atmospheric deposition; however, an additional study is needed to confirm this.

Dispersion modeling and health risk assessment of dioxin emissions from a municipal solid waste incinerator in Hangzhou, China

The emission of dioxins from municipal solid waste incinerators (MSWIs) has become a widespread concern. The effect of meteorological parameters (wind speed, atmospheric stability and mixing height) on the hourly ground level concentration (GLC) of dioxins was estimated using air dispersion models. Moreover, the health risks of dioxin exposure were evaluated for children and adults using the Nouwen equation. The total environmental exposure via air inhalation and food ingestion was calculated, based on linear fit equations. The results indicate that potentially severe pollution from dioxins occurs at a wind speed of 1.5 m/s with atmospheric stability class F. In addition, local residents in the study area are exposed to severe weather conditions most of the time, and the risk exposures for children are far higher than those for adults. The total exposure for children far exceeds the tolerable daily intake of dioxin recommended by the World Health Organization (WHO) of 1–4 pg TEQ/(kg·d) under severe weather conditions. Results from modeling calculations of health risk assessment were consistent with dioxin levels obtained during actual monitoring of emissions.

Concentrations of polychlorinated dibenzo- p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls in blood and breast milk collected from pregnant women in Sapporo City, Japan

We measured the concentrations of polychlorinated dibenzo- p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs), and non-dioxin-like PCBs in paired samples of blood and breast milk collected from 67 secundiparas in Sapporo City, Japan, and combined this data with those of the 30 secundiparas previously measured. The arithmetic mean total toxic equivalents (TEQ-WHO) concentrations of PCDDs, PCDFs, non- ortho PCBs, and mono- ortho PCBs in blood and breast milk of the 97 secundiparous subjects were 3.0–23 (mean: 13, median: 14) and 2.7–20 (mean: 8.6, median: 8.5) pg TEQ g −1 lipid, respectively. The sums of the concentrations of 56 non-dioxin-like PCB congeners that were measured in the subjects’ blood and breast milk were 16–326 (mean: 107, median: 100) and 12–252 (mean: 73, median: 67) ng g −1 lipid, respectively. The partitioning ratios of individual congeners of PCDDs, PCDFs, dioxin-like PCBs, and non-dioxin-like PCBs from blood to breast milk in secundiparas were almost the same as those of primiparas that have been recently reported, suggesting that the partitioning ratios of these compounds from maternal blood to breast milk in women is little affected by delivery. Furthermore, the partition of PCB congeners with chlorine at the 2-, 3-, 4′-, and 5-positions or the 2-, 4-, 4′-, and 5-positions of the biphenyl ring from the blood to the breast milk tended to occur at a higher level than that of other congeners. In particular, the levels of tetraCB-74 and hexaCB-146 in the breast milk for both primiparous and secundiparous mothers were slightly higher than those in the blood.

PAHs, PCBs, PBDEs and Pesticides in Cold‐Pressed Vegetable Oils

The aim of this study was to investigate levels of polychlorinated biphenyls (marker and dioxin-like congeners), polycyclic aromatic hydrocarbons (EPA 15 + 1), polybrominated diphenyl ethers (14 predominant congeners) and pesticides (74 compounds) in various cold-pressed vegetable oils. Poppy seed oil, rapeseed oil, sesame seed oil, pumpkinseed oil, hempseed oil, linaire oil, borage oil and evening star oil were investigated. Results of this study revealed that concentrations of PCBs, PBDEs and PAHs were low in majority of the investigated samples. However, high concentrations of organophosphorus insecticides were found. Chlorpyrifos methyl and pirimiphos methyl were the pesticide residues most commonly found in the studied oils. Concentration of 15 + 1 EPA PAHs was within the 17.85–37.16 μg kg−1 range, concentration of (marker) PCBs varied from 127 to 24,882 pg g−1, dioxin-like TEQ values were below 0.1 pg TEQ g−1. Concentration of PBDEs was below LOQ in most cases.

Levels of PCDD/Fs, PCBs and PBDEs in butter from Turkey and estimated dietary intake from dairy products

Polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs), dioxin-like and non-dioxin-like (indicator) polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs) were monitored in butterfat obtained from 18 different areas in Turkey, both rural and industrial. The results obtained both at RIKILT in the Netherlands and in a food control laboratory in Turkey for PCDD/Fs and PCBs were in good agreement. The sum of PCDD/Fs+dl-PCBs, total indicator PCBs and PBDEs were in the range 0.26–3.82 pg TEQ g−1 fat, 0.20–3.04 ng g−1 fat and 0.18–5.00 ng g−1 fat, respectively. Despite the very low levels measured, slightly elevated PCDD/F and PCB levels were found in İzmir-Aliağa, Kocaeli, Denizli, and Zonguldak. The only result exceeding the EU action level was the dl-PCB concentration in İzmir-Aliağa. Ratios of PCDD/Fs and PCBs indicate that contamination in the elevated areas originated from different sources. High BDE 209 levels were detected in Mersin and Bursa. For the 18 regions analysed, the average total daily intake of total TEQ (dioxins and dl-PCBs) from butterfat was 0.09 pg TEQ(1998) (0.08 pg TEQ(2005)) kg−1 body weight, while those for indicator PCBs and PBDEs were 58.8 and 35.1 pg kg−1 body weight, respectively. The average total daily intake from dairy products were 0.26 pg TEQ(1998) (0.20 pg TEQ(2005)), 183 and 103 pg kg−1 body weight, respectively.

PCDD, PCDF, PCB and PBDE concentrations in breast milk of mothers residing in selected areas of Slovakia

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polybrominated diphenylethers (PBDEs) in 33 breast milk samples collected in 2006–2007 from primipara mothers close to four industrial areas of Slovak Republic were determined. The total PCDDs/PCDFs and dl-PCBs expressed as TEQ based on WHO TEFs 1998 in breast milk samples varied from 5.0 to 51.8 pg g −1 fat (median: 13.1 pg g −1 fat; mean: 18.0 pg g −1 fat). The measurements of seven PBDE congeners (IUPAC No. 28, 47, 99, 100, 153, 154, and 183) were performed for the first time in human milk from Slovakia. PBDE levels ranged between 0.22 and 1.62 ng g −1 fat, with median and mean value of 0.43 ng g −1 fat and 0.57 ng g −1 fat respectively. No statistically significant differences were observed between studied areas in total PBDE concentrations. Furthermore, this study presents first results concerning the daily intake (DI) of PCDDs/PCDFs and dioxin-like compounds for the most vulnerable breast-fed infant population in Slovakia. The total PCDD/PCDF and dl-PCB DI for an infant during the first 2 months of life was estimated in a range from 14.4 to 230 pg TEQ kg −1 b.w., with a median value of 58.9 pg TEQ kg −1 b.w.. The DI values substantially exceeded the tolerable daily intake (TDI) 1–4 pg TEQ kg −1 b.w. recommended by WHO. The dietary infant intake concerning PBDEs was estimated to be between 0.69 and 7.1 ng kg −1 b.w. d −1, with median value of 1.7 ng kg −1 b.w. d −1.

Exposure to PCBs, through inhalation, dermal contact and dust ingestion at Taizhou, China – A major site for recycling transformers

Air samples containing gaseous and particulate phases were collected from e-waste workplaces and residential areas of an intensive e-waste recycling area and compared with a reference site. The highest total concentration of PCBs was detected at transformer recycling workshops (17.6 ng m −3), followed by the residential area (3.37 ng m −3) at Taizhou, and the lowest was obtained at the residential area of the reference site, Lin’an (0.46 ng m −3). The same trend was also observed with regards to PCB levels in dust samples. The highest average PCBs level of 2824 ng g −1 (dry wt) was found in the transformer recycling workshops, and was significantly higher than that of residential areas of Taizhou (572 ng g −1 dry wt) and Lin’an (42.4 ng g −1 dry wt). WHO-PCB-TEQ level in the workshops of Taizhou was 2216 pg TEQ 1998 g −1 dry wt or 2159 pg TEQ 2005 g −1 dry wt, due to the high abundance of PCB 126 (21.5 ng g −1 dry wt), which contributed 97% or 99% of WHO-PCB-TEQs. The estimated intake of PCBs via dust ingestion and dermal absorption by transformer recycling workers were 77.5 × 10 −5 and 36.0 × 10 −5 pg WHO-PCB-TEQ 1998 kg −1 d −1, and 67.3 × 10 −5 and 31.3 × 10 −5 pg WHO-PCB-TEQ 2005 kg −1 d −1, respectively.

Formation of polychlorinated dibenzo- p-dioxins/dibenzofurans (PCDD/Fs) from a refinery process for zinc oxide used in feed additives: A source of dioxin contamination in Chilean pork

The Republic of Korea found dioxin at concentrations exceeding the Korean maximum residue limit (MRL) in pork (2 pg TEQ g −1 fat) imported from Chile in June 2008. Korea and Chile collaborated and investigated to find out the sources of contamination. An isotope dilution method and high resolution gas chromatography/mass spectrometry (HR–GC/MS) were used for the analysis of PCDD/Fs. PCDD/Fs were found from 2.17 to 36.7 pg TEQ g −1 fat from Chilean pork. 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, and 2,3,4,6,7,8-HxCDF were found as the major congeners in pork samples. 2,3,4,7,8-PeCDF showed the highest concentration and contributed about 30% among the congeners in most of the samples. 2,3,7,8-TCDD, 1,2,3,7,8,9-HxCDD, OCDD, 2,3,7,8-TCDF, 1,2,3,7,8-PeCDF, 1,2,3,7,8,9-HxCDF, and OCDF were not detected or exist at background levels in the less contaminated samples. Remarkably high concentrations of PCDD/Fs were found in samples of zinc oxide (17 147 pg TEQ g −1), zinc oxide based premix (6673 pg TEQ g −1), and the residue crust (800 pg TEQ g −1) in a mixing chamber in the feed mill. From the results of various investigations, this case concluded that zinc oxide in the feed was the major source of the dioxin contamination in pork. The dioxins were formed from a metal refinery process to collect zinc oxide.

Tracing and analytical results of the dioxin contamination incident in 2008 originating from the Republic of Ireland

High levels of dioxins (PCDD/Fs) in pork were discovered in France and the Netherlands at the end of 2008. The contamination was rapidly traced back to a feed stock in the Republic of Ireland (RoI). Burning oil, used for the drying of bakery waste, appeared to be contaminated with PCBs. Consequently, very high levels up to 500 pg TEQ g−1 fat were found in pork. The congener pattern clearly pointed to PCB-oil as a source, but the ratio between the non-dioxin-like indicator PCBs (PCBs 28, 52, 101, 138, 152 and 180) and PCDD/Fs was much lower than observed during the Belgian incident, thereby limiting the suitability of indicator PCBs as a marker for the presence of dioxins and dioxin-like PCBs. This paper describes the tracking and tracing of the incident, the public–private cooperation, the surveillance activities and its results. A major lesson to be learned from this incident is the importance of good private food safety systems. In this incident, it was the private surveillance systems that identified the origin of contamination within 10 days after the first signal of increased dioxin levels in a product. On the other hand, retrospective analyses showed that signals were missed that could have led to an earlier detection of the incident and the source. Above all, the incident would not have occurred when food safety assurance systems had been effectively implemented in the involved feed chain. It is discussed that besides primary responsibility for effective private food safety systems, the competent authorities have to supervise whether the food safety procedures are capable of coping with these kinds of complex food safety issues, while private food companies need to implement the law, and public authorities should supervise and enforce them. Finally, it is discussed whether the health risks derived from consumption of the contaminated batches of meat may have been underestimated during the incident due to the unusually high intake of dioxins.

Dietary exposure to PCBs based on food consumption survey and food basket analysis at Taizhou, China – The World’s major site for recycling transformers

The levels of PCBs in different types of food (fish, shellfish, meat, rice, vegetables, and fruits) were analyzed to determine the dietary intake of 37 PCBs for local residents and e-waste workers (all lactating mothers) at Taizhou (China), a major electronic waste scrapping center, in particular for recycling transformers. The exposure to PCBs through dietary intake in Taizhou was estimated at 92.79 ng kg −1 d −1, contributed by consumption of freshwater fish (28%), rice (28%), meat (17%), shellfish (9%), vegetables (8%), egg (4%) and marine fish (2%). With regards to WHO-PCB-TEQ values, freshwater fish (40%), shellfish (24%), duck liver (18%) and rice (12%) were the main dietary sources with total daily intake (9.78 pg WHO-PCB-TEQ kg −1 d −1), exceeding the FAO/WHO Tolerable Daily Intake (70 pg TEQ kg −1 body −1 wt −1 month −1).

Estimation and Characterization of Polychlorinated Naphthalene Emission from Coking Industries

Occurrence of polycyclic aromatic hydrocarbons (PAHs) during the coking process has been widely recognized. The formation of polychlorinated naphthalenes (PCNs) from PAHs during some thermal related processes has been confirmed in many studies. Thus, the coking process is assumed to be a potential source of PCNs. However, intensive investigations on PCN emissions during the coking process are lacking. In order to evaluate PCN emissions from the coking process, an intensive study comprising 11 typical coke plants was undertaken. PCNs were qualified and quantified by isotope dilution HRGC/HRMS techniques. The concentrations of PCNs in stack gas samples collected from the investigated coke plants were in the range of 1.6-91.8 ng Nm(-3) (0.08-4.23 pg TEQ Nm(-3)). The emission factors of PCNs were found to be in the range of 0.77-1.24 ng TEQ per ton of coke production. The estimated annual toxic emissions of PCNs from the global coking industry vary from 430 to 692 mg TEQs. Characteristics of the PCN profiles were dominated by the lower chlorinated homologues, with mono-CN being the most abundant homologue. According to the PCN distribution and correlations of PCN homologues, it was speculated that chlorination is possibly the dominant pathway of PCN formation during the coking process.

Exposure assessment of dioxins and dioxin-like PCBs in pasteurised bovine milk using probabilistic modelling

Quantitative exposure assessment is a useful technique to investigate the risk from contaminants in the food chain. The objective of this study was to develop a probabilistic exposure assessment model for dioxins (PCDD/Fs) and dioxin-like PCBs (DL-PCBs) in pasteurised bovine milk. Mean dioxins and DL-PCBs (non- ortho and mono- ortho PCBs) concentrations (pg WHO-TEQ g −1) in bovine milk were estimated as 0.06 ± 0.07 pg WHO-TEQ g −1 for dioxins and 0.08 ± 0.07 pg WHO-TEQ g −1 for DL-PCBs using Monte Carlo simulation. The simulated model estimated mean exposure for dioxins was 0.19 ± 0.29 pg WHO-TEQ kg −1 bw d −1 and 0.14 ± 0.22 pg WHO-TEQ kg −1 bw d −1 and for DL-PCBs was 0.25 ± 0.30 pg WHO-TEQ kg −1 bw d −1 and 0.19 ± 0.22 pg WHO-TEQ kg −1 bw d −1 for men and women, respectively. This study showed that the mean dioxins and DL-PCBs exposure from consumption of pasteurised bovine milk is below the provisional maximum tolerable monthly intake of 70 pg TEQ kg −1 bw month −1 (equivalent of 2.3 pg TEQ kg −1 bw d −1) recommended by the Joint FAO/WHO Expert Committee on Food Additives and Contaminants (JECFA). Results from this study also showed that the estimated dioxins and DL-PCBs concentration in pasteurised bovine milk is comparable to those reported in previous studies.

Polychlorinated biphenyls (PCBs) contamination and aryl hydrocarbon receptor (AhR) agonist activity of Omega-3 polyunsaturated fatty acid supplements: Implications for daily intake of dioxins and PCBs

Omega-3 polyunsaturated fatty acid (n-3 PUFA) rich oils derived primarily from fish are frequently consumed as supplements. Due to the tendency of persistent organic pollutants (POPs) to accumulate in exposed organisms, n-3 PUFA supplements can contain sufficient POPs to present a risk to consumers. Here we investigated PCB concentrations and aryl hydrocarbon receptor (AhR) agonist activity in 17 n-3 PUFA supplements available in Canada. PCBs ranged from <0.8 to 793 ng g −1 oil, with salmon- and seal-derived products yielding the highest values. AhR agonist activity from a reporter gene assay ranged from 1.3 to 72.2 pg TEQ g −1 oil, with salmon and tuna yielding the highest values. When consumed at the recommended doses and as a supplement to the average Canadian diet, seal-derived oil can contribute to exceedance of the tolerable daily intake of 20 ng PCBs kg-BW −1 day −1, and salmon-, tuna-, and sea herring-derived oils can contribute to exceedance of the tolerable daily intake limit of 2.3 pg TEQ kg-BW −1 day −1. The beneficial properties of fish and n-3 PUFA supplements, and the results of this study suggest that it is prudent to consume supplements derived from small, cold-water fatty fish. Further research will be necessary to draw firm conclusions.

PCDD, PCDF and PCB contamination in Atherina boyeri (Risso, 1810) from Turkey

The levels of polychlorinated dibenzo- p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DL-PCBs) and indicator polychlorinated biphenyls were measured in Atherina boyeri (Risso, 1810) samples collected from Hirfanlı Dam Lake, Turkey in 2008 and 2009. Concentrations of PCDDs–PCDFs were detected as 0.16 and 0.17 pg TEQ (1998) g −1 wet weight while contamination levels of DL-PCBs were found as 0.42 and 0.38 pg TEQ (1998) g −1 wet weight in fish samples. The concentrations of total indicator PCBs in fish samples were found as 1.5 ng g −1 and 0.9 ng g −1 wet weight. Concentrations of PCDDs–PCDFs and DL-PCBs were below the EU regulation limits.

Levels of PCDD/Fs in local and non-local food samples collected from a highly polluted area in Turkey

A sampling and analysis program were conducted to determine the PCDD/F levels in various food samples collected in Kocaeli, one of the highly polluted areas in Turkey. Several food samples including animal (egg, chicken, meat and cow’s milk) and plant (fruits, leafy vegetables, fruiting vegetables, rooty vegetables and flour) products were collected from both local and non-local (commercial) sources. The local food samples were taken from 20 sampling points selected by taking into account the location of the possible PCDD/F sources, dominant wind directions and representing the major part of the Turkish daily diet The PCDD/F concentrations in local eggs and milk samples were ranged from <1.16 to 10.94 pg TEQ g −1 fat and from <0.43 to 3.29 pg TEQ g −1 fat, respectively. On the other hand, the PCDD/F concentrations were measured between 0.28–1.81 pg TEQ g −1 fat in local meat samples and 0.15–2.92 pg TEQ g −1 fat in local chicken samples. The PCDD/F concentrations in the plant products were relatively low and most of the congeners were measured below the detection limits except for the leafy vegetables. In addition, several commercial samples were analyzed in order to evaluate the differences of PCDD/F levels in samples collected from both the local and non-local sources. The results showed that the local animal products have higher PCDD/F concentrations than the non-local ones. Moreover, the commercial plant products showed undetectable concentrations for most of the congeners. Finally, the PCDD/F levels in some animal products were found to be higher than the national limit values.

Depletion study of PCDD/Fs and dioxin-like PCBs concentrations in contaminated home-produced eggs: Preliminary study

Dioxins (PCDD/Fs) and polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants. The contamination of food products with dioxins and PCBs is a well studied issue, because food is generally considered the major source of dioxin intake for humans. In Italy, the Regional Monitoring Plan (part of the national residue monitoring plan) used in the field for 2009 has also included the control of environmental pollutants in small egg producers. Following an irregular result, 12 laying hens were transferred into a laboratory controlled environment. Eggs were collected for 60 days and they were weekly analysed for the evaluation of dioxins, dioxin-like PCBs (DL-PCBs), and non-dioxin-like PCBs (NDL-PCBs, six congeners) levels. The dioxins and PCBs contents were determined, according to EPA methods, by gas chromatography ic determination coupled with high resolution mass spectrometry (HRGC-HRMS). The content of PCDD/Fs, DL-PCBs and NDL-PCBs was evaluated weekly by mean from week to week. The concentration of dioxins was lower than DL-PCBs (2.5 pg TEQ g −1 of fat against 4.5 pg TEQ g −1 of fat), but we observed the same depletion trend for both pollutants. On the opposite, NDL-PCBs had a different course: we noted there was an increase between weeks 6 and 7, but the mean levels remained very low (about 20 ng g −1 of fat). The dioxins, and sum of dioxin and DL-PCBs concentration were below the fixed European limits (i.e. 3 pg TEQ g −1 of fat for dioxins and 6 pg TEQ g −1 of fat for sum of dioxins and DL-PCBs), beginning from the 3rd week of trial.

Dietary intake of PCDD/Fs and dioxin-like PCBs of the Belgian population

The World Health Organization recommends assessing human exposure to contaminants on a regular basis. In order to assess the current dietary exposure of the Belgian adult population to PCDD/Fs and dioxin-like PCBs and to update exposure estimates of 2000–2001, a total diet study was designed. The mean dietary intake of PCDD/Fs and dioxin-like PCBs in the Belgian adult population in 2008 was estimated to be 0.72 pg TEQ kgbw −1 d −1 (middle bound concentrations, TEF of 1998) based on occurrence data of 2008 and national food consumption data of 2004. This value is clearly below the Tolerable Weekly Intake (TWI) of 14 pg TEQ kgbw −1 week −1 set by the Scientific Committee on Food of the European Commission and below the provisional tolerable monthly intake of 70 pg TEQ kgbw −1 month −1 set by the Joint FAO/WHO Expert Committee on Food Additives. Considering the cumulative distribution, the intake was less than 1 pg TEQ kgbw −1 d −1 for more than 80% of the population, and less than 2 pg TEQ kgbw −1 d −1 for the entire population. When using the 2005 TEF instead of the 1998 TEF, the mean dietary intake in the Belgian adult population was estimated to be 0.61 pg TEQ kgbw −1 d −1.

Contamination levels and congener distribution of PCDDs, PCDFs and dioxin-like PCBs in buffalo’s milk from Caserta province (Italy)

An extraordinary plan of official control was carried out in 2008 in Campania (Italy) with the aim to monitor polychlorinated dibenzo- p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) levels in buffalo milk and to detect the contaminated farms, most of which are located in Caserta province. For these companies has been ordered seizure and execution of additional analyses has been requested in farms falling in the nearness, within a distance of 3 km, for a total of 304 farms examined. Moreover, all non-compliant farms were subjected to a periodic sampling in order to monitor trends in the levels of contamination. In this paper the distribution and the concentrations of 17 PCDD/Fs and 12 dioxin-like PCBs in 460 samples of buffalo milk collected in the province of Caserta (Italy) are presented. The range of WHO-TEQ values for the PCDD/Fs in milk was 0.17 pg TEQ g −1 fat and 87.0 pg TEQ g −1 fat with a mean value 3.63 pg TEQ g −1 fat and medium value 2.25 pg TEQ g −1 fat. The concentrations of dioxin-like PCBs in the analysed samples ranged from 0.21 pg TEQ g −1 fat to 15.9 pg TEQ g −1 fat and the WHO-TEQ values of sum of PCDDs, PCDFs and dl-PCBs ranged from 0.45 pg TEQ g −1 fat to 103.0 pg TEQ g −1 fat. The geo-referencing analysis allowed to individuate a restricted area of the region object of the present study where is located the majority of the non-compliant farms. The study of the congeners distribution has finally suggested that the likely cause of contamination is to be attributed to the illegal burning of waste.

Levels of polychlorinated dibenzo- p-dioxins, dibenzo- p-furans and polychlorinated biphenyls in farmed sea bass ( Dicentrarchus labrax) and sea bream ( Sparus aurata) from Turkey

Farmed European sea bass and Gilthead sea bream were obtained from four different fish farms in Turkey during 2008–2009, for determination of 17 2,3,7,8-Cl-substituted PCDDs and PCDFs, and coplanar and indicator PCBs. Concentrations of ∑PCDD/Fs and DL-PCBs, as TEQ, in fish samples, ranged from 0.14 to 0.70 pg TEQ (1998) g −1 wet weight and from 0.46 to 4.51 pg TEQ (1998) g −1 wet weight, respectively. The concentrations of total indicator PCBs in fish samples ranged from 3.1 ng g −1 to 22.1 ng g −1 wet weight. Concentrations of PCDD/Fs and DL-PCBs were below the EU regulation (EC No. 1881/2006) limits.