Dioxins in adipose tissue of non-occupationally exposed persons in France: correlation with individual food exposure

We evaluated individual adipose tissue (subcutaneous lipomas) dioxin contamination in non-occupationally exposed persons living in France (adult patients undergoing a surgical ablation of benign lipomas), in relation to the corresponding individually evaluated mean daily dietary dioxin intake (DDDI). The diet survey (questionnaire) included information on consumption of meat, fish, milk and dairy products, from which the individual DDDI was calculated. Sixteen subjects participated in this study. DDDI ranged between 1.06 and 3.31 pg I-TEQ/kg body weight, bw (mean value: 2.05+/-0.72). Adipose tissue polychlorinated dibenzo-p-dioxins (PCDD)/polychlorinated dibenzofurans (PCDF) levels ranged between 18.5 and 76.9 pg I-TEQ/g lipids (mean value: 35.6+/-14.8). No relation was found between the DDDI and adipose tissue PCDD/PCDF concentrations. The mean DDDI in France does not fundamentally differ from those found in other industrialised countries, is within the range of 1-4 pg I-TEQ/kg/day recently suggested by WHO-ECEH/ICPS for the tolerable daily intake of dioxins. Adipose tissue PCDD/PCDFs levels are similar to levels in other European countries and USA without relation to sex or age, and can be considered representative European background concentrations. Globalisation of alimentary production leads to a similar food exposure in Western European countries, in spite of dioxins accidental selective contaminations that are epiphenomenon and thus do not have any impact in human dioxin background levels.     

Perfluorinated alkylated substances in vegetables collected in four European countries; occurrence and human exposure estimations

The human diet is recognised as one possible major exposure route to the overall perfluorinated alkylated substances (PFAS) burden of the human population, resulting directly from contamination of dietary food items, as well as migration of PFAS from food packaging or cookware. Most European countries carry out national monitoring programs (food basket studies) to monitor contamination with pollutants. Usually, for PFASs, non-coordinated approaches are used in Europe, since food basket studies are mainly carried out by national authorities following national requirements and questions, making comparisons between different countries difficult. A harmonised sampling campaign collecting similar food items in a uniform procedure enabling direct comparison between different regions in Europe was designed. We selected four countries (Belgium, Czech Republic, Italy and Norway), representing the four regions of Europe: West, East, South and North. In spring 2010 and 2011, 20 different types of vegetables were sampled in Belgium, Czech Republic, Italy and Norway. Perfluorinated carboxylic acids (PFCAs) were the main group of detected PFASs, with perfluorinated octanoic acid (PFOA) as the most abundant PFCA (with exception of samples from Czech Republic), followed by perfluorinated hexanoic acid and perfluorinated nonanoic acid. Dietary intake estimates for PFOA show only low human exposure due to vegetable consumption for adults and children, mostly governed by high intake of potatoes.     

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.     

Certification of a long-term sampling system for PCDFs and PCDDs in the flue gas from industrial facilities

AMESA (adsorption method for sampling of dioxins) is a fully automatic system for long term monitoring of dioxin emissions from industrial processes based on the adsorption method. The system has been tested and undergoing a certification procedure according to the German guidelines for certification of systems for continuous monitoring of special substances. The certification covered parameters such as disposability of the system, reproducibility of the results and comparability of the sampling method with German and European standard methods. Furthermore break through, blanks and sample storability were investigated. The results prove that AMESA is a state of the art sampling system for continuous monitoring of dioxin/furan emissions.     

Dioxins and related compounds: Status and regulatory aspects

Several countries have put much effort in dioxin research programmes with the aim to assess the risks of dioxin exposure, to identify dioxin sources and to quantify their contribution to environmental emissions and human exposure. In this review, the accent has been put on: sources of dioxins and their contribution to the total dioxin emissions, sources of human exposure and their contribution to exposure and measures to reduce emission and exposure. The information from countries with existing dioxin regulations is reviewed and compared. Uncertainties which hamper comparability of data are indicated. Results of measures and expectations for the near future are presented.     

PCDD/F levels in plasma of a belgian population before and after the 1999 belgian PCB/DIOXIN incident

We evaluated the impact of the 1999 Belgian dioxin incident on the blood plasma polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) levels among 232 Belgian blood donors (74% men, mean age 47 years). The Red Cross made plasma samples from before the incident of these donors available. A second plasma sample was collected during the second half of 2000. The sum of the 17 PCDD/F congeners was significantly lower in 2000 compared to 1998 (417 pg/g fat versus 445 pg/g fat, respectively). This could be completely attributed to the significant decrease of OctaCDD (301 pg/g fat in 2000 versus 277 pg/g fat in 1998). Moreover a slight but significant decrease was observed for 2,3,7,8-TetraCDF and for 1,2,3,4,6,7,8-HeptaCDF. 1,2,3,7,8-PentaCDF and 2,3,4,7,8-PentaCDF however showed a slight but significant increase (respective levels in 1998 were 0.004 and 14.5 pg/g fat compared to 0.006 and 17.9 pg/g fat in 2000). Given their significantly higher presence in incident related food samples this increase can be attributed to the food contamination episode. However, the total toxicity remained unchanged (22.9 in 1998 versus 23.1 pg WHO-TEQ/g fat, p>0.05). Moreover the observed congener profiles and the total PCDD/F levels were similar to those of other European non-occupationally exposed populations. In conclusion, the 1999 PCB/dioxin incident was traceable in the plasma profiles (rise of the two specific PCDF congeners), but comparison of the results for both years indicates that the changes were too small to cause an adverse public health effect.     

Optimization of the purification method for dioxin analysis in human serum and temporal changes in background dioxin levels in the general population

To perform high quality and high throughput measurements, complicated purification procedure by two rounds of open column chromatography was simplified by appraising the components and adding a sufficient amount of adsorbents to the column. The procedure consists of two open column techniques using a multi-layer silica gel column and an active carbon dispersed silica gel column. This purification procedure is used in "Standard manual for dioxin analysis in human blood" published in 2000 (Ministry of Health and Welfare, Japan, 2000). Consequently, a purification procedure using only 1 g of 10% AgNO(3)/silica gel can remove the matrix of blood serum as effectively as a multi-layer silica gel column. In addition, 0.1 g of carbon silica gel, equivalent to 1/10 the weight used currently in analyses, separates and recovers the dioxins in purified extract of blood serum. Furthermore, changes in the background level in the general population were clarified by monitoring the dioxin concentrations in human blood. The dioxin concentrations and ratios in blood in the general population remained at a tolerable level for three months. Therefore, the blood serum was available for the detection of a remarkable elevation in dioxins level considered to be indicative of contamination due to high-density exposure.     

Health risk assessment of dioxin emissions from municipal waste incinerators: the Neerlandquarter (Wilrijk, Belgium)

Two municipal waste incinerators in the vicinity of a residential area close to the city of Antwerp caused concern to local habitants. Risk assessment was performed combining chemical, toxicological measurements and model calculations. As the first step in risk assessment an inventory was made of historic emissions from both incinerators with emphasis on dioxins. The operational atmospheric transport and deposition model for priority substances (OPS) was used to calculate the deposition of dioxins in the vicinity of incinerators. The observed soil contamination pattern did not correspond to the calculated deposition pattern, indicating that other sources may contribute at least partly to the local PCDD/PCDF contamination of the area. Dioxin exposure of people in the Neerlandquarter as a function of the food consumption behavior was calculated using a mathematical model (VLIER-HUMAAN) combined with transfer factors. According to the results of these calculations, just residing in the impact area does not result in a meaningful risk. Only if locally produced food was consumed (milk, meat and vegetables), exposure in the Neerlandquarter was enhanced compared to the average dioxin exposure estimated for the Flemish population. Exposure in 1997 was below the exposure in 1980. As a consequence of different eating habits and lower bodyweight, children are subjected to significantly higher exposure than adults. Adverse health outcomes from dioxin exposure in the past cannot be excluded. There was no evidence for enhanced exposure to genotoxicants based on a comparison of chromosomal damage to blood cells of children from the study area to those from a control group.     

Residues of dioxins and PCBs in fat of growing pigs and broilers fed contaminated feed

To investigate the kinetics of PCBs and dioxins, 3 week old broilers and 3 month old pigs were fed with a 10-fold diluted feed from the Belgium crisis for one week, followed by a period on clean feed. In the case of broilers this resulted in levels for dioxins, non-ortho and mono-ortho PCBs in fat of 102, 84 and 216 ng TEQ/kg, summarized to 402 ng TEQ/kg. Total levels decreased to 217 and 109 ng TEQ/kg after 1 and 3 weeks on clean feed. Indicator PCB levels decreased from an initial 6.2 mg/kg fat to respectively 3.2 and 1.5 mg/kg. The ratio of indicator PCBs to dioxins TEQs was stable over this period. Levels in back fat of pigs at the end of the exposure period were 26, 15, 82 and 123 ng TEQ/kg for respectively dioxins, non-ortho PCBs, mono-ortho PCBs and the sum. Total TEQ levels decreased to respectively 95, 70, 40, 22 and 12 ng TEQ/kg after 1, 2, 4, 8 or 12 weeks on clean feed. After 12 weeks dioxin levels were around 1 ng TEQ/kg. Indicator PCB levels decreased from 3.48 mg/kg to 2.65, 2.01, 1.25, 0.76 and 0.45 mg/kg fat, again after 1, 2, 4, 8 or 12 weeks on clean feed. Levels of dioxins decreased more rapidly than those of indicator PCBs, also reflected by the ratio of indicator PCBs to dioxins, being 133,000 at the end of the exposure period and 357,000 after week 12. It is concluded that the use of indicator PCBs for dioxins, in the case of a combined exposure, is a safe alternative for screening and in the case of pigs results in an overestimation rather than underestimation of the dioxin levels.     

Human exposure to dioxins through the diet in Catalonia,Spain: carcinogenic and non-carcinogenic risk

The main objectives of this study were to estimate the dietary intake of dioxins by the population of Catalonia, Spain, to determine which food groups showed the greatest contribution to this intake, and to assess the health risks potentially associated with the dietary dioxin intake. From June to August 2000, food samples were randomly acquired in seven cities of Catalonia. Dioxin concentrations were determined in 108 samples belonging to the following groups: vegetables, fruits, pulses, cereals, fish and shellfish, meats and meat products, eggs, milk and dairy products, and oils and fats. Estimates of average daily food consumption were obtained from recent studies. Total dietary intake of dioxins for the general population of Catalonia was estimated to be 95.4 pg WHO-TEQ/day (78.4 pg I-TEQ/day), with fish and shellfish (31%), diary products (25%), cereals (14%) and meat (13%) showing the greatest percentages of contribution to dioxin intake. The contribution of all the rest of food groups to the total dietary intake was under 20%. The non-carcinogenic risk index of dioxin intake through the diet was in the range 0.34-1.36, while the carcinogenic risk level was 1,360 excess cancer over a lifetime of 70 years. Our results corroborate the decreasing tendency in dietary intake of dioxins found in recent studies (2000-2001) from various countries.     

Bioaccumulation and trophic transfer of dioxins in marine copepods and fish

Despite the great concerns about dioxins in the marine environments, the biokinetics and bioaccumulation of these compounds in marine organisms remains little known. Using radioactive tracers the aqueous uptake, dietary assimilation efficiency, and elimination of dioxins were measured in marine phytoplankton, copepods and seabream. The calculated uptake rate constant of dioxins decreased with increasing trophic levels, whereas the dietary assimilation efficiency (AE) was 28.5-57.6% in the copepods and 36.6-70.2% in the fish. The dietary AE was highly dependent on the food concentrations and food type. The elimination rate constant of dioxin in the copepods varied with different exposure pathways as well as food concentration and food type. Biokinetic calculation showed that dietary accumulation was the predominant pathway for dioxin accumulation in marine copepods and fish. Aqueous uptake can be an important pathway only when the bioconcentration of dioxins in the phytoplankton was low.     

Model selection and evaluation for risk assessment of dioxin-contaminated sites

The general European population has a total intake of dioxins and dioxin-like chemicals near the limit recommended by the European Union, making additional exposure above background levels undesirable. For populations living near dioxin-contaminated sites, additional exposure may occur by intake of locally produced food, inhalation of particles, dermal contact with soils, or other exposure pathways. Risk assessment tools are required to estimate risks associated with contaminated sites and to set priorities for site remediation. Here, we review several multimedia models that can be applied as tools to support risk assessment. We then present a strategy to select, apply, evaluate, and adapt a model to address a specific situation. The case study we consider is a risk assessment of generic background dioxin exposure in Sweden, and we compare the predictions with environmental observations and exposure data from Sweden. Arguments are presented for selecting the CalTOX model for this case study. We demonstrate the application, evaluation, and adaptation of the model and discuss the requirements for extending the analysis to conduct risk assessment for subpopulations living near dioxin-contaminated sites.     

Assessment of dietary exposure to PCDD/F and dioxin-like PCB in infant formulae available on the EU market

In infant period, human milk and infant formulae are the major sources of exposure to dioxins (polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCB). Since in many parts of Europe the mothers are increasingly reluctant to breastfeed their babies, the main objective of the present study is to assess the level of exposure of non-breast-fed infants during their early development. Consequently, the concentration levels of PCDD/F and dioxin-like PCB were determined in industrial infant formulae including "starting" (aged 0-4months) and "follow-on" (after 4months) products of milk formula, soy formula and hypoallergenic infant formula, available on the EU market. Furthermore, dietary exposure to dioxin of exclusively formula-fed infants was assessed at each month from 0 to 9months. The results suggest that dietary exposure to dioxins via formulae is higher when consuming "starting" than "follow-on" infant formulae on a body-weight basis. Estimated dietary exposure after 4months of age was always below the lowest range of the Tolerable Daily Intake (TDI) of 1pg WHO-TEQkg(-1)bwd(-1) and Provisional Tolerable Monthly Intake (PTMI) of 70pg WHO-TEQkg(-1)bwmonth(-1). The highest estimated cumulative dietary exposure to PCDD/F and dioxin-like PCB was obtained considering infants of 0-1months fed with the "starting" hypoallergenic infant formula (2.8pg WHO-TEQkg(-1)bwd(-1) and 84pg WHO-TQkg(-1)bwmonth(-1)). However, these elevated levels are much lower than those observed in some studies in breast-fed infants. The study can be used for further risk assessments in regard to infant exposure.     

Risk assessment of dioxins and dioxin-like PCBs in food--comments by the German Federal Environmental Agency

Human health risk assessments for dioxins and dioxin-like PCBs (with the exception of the one by US-EPA) recommend health based exposure limits within the range of 1-4 pg WHO-TEQ/kg bw per day. As all humans are exposed to measurable levels of dioxins and related substances, the determination of the tolerated daily intake is a very significant decision and may influence limit values guiding risk reduction measures and target levels. The proposed TDI has to protect all human subpopulations. In the case of dioxin this is particularly important as the exposure of infants through breast-feeding may exceed the exposure of adults by one or two orders of magnitude. An overview of recently recommended limit values (WHO, SCF, JECFA) for PCDDs, PCDFs and dioxin-like PCBs using WHO-TEFs shows the common feature that the values were derived only from non carcinogenic endpoints. In November 2000 the Scientific Committee on Food of the European Commission published an 'Opinion of the SCF on the Risk Assessment of Dioxins and Dioxin-like PCBs in Food' [SCF, Scientific Committee on Food 2000. Opinion of the SCF on the risk assessment of dioxins and dioxin-like PCBs in food. European Commission, Brussels, Adopted on November 2000 http://europa.eu.int/comm/food/fs/sc/scf/out78_en.pdf]. On the basis of this extensive review of data and experimental results the Committee recommended a temporary tolerable weekly intake (t-TWI) of 7 pg WHO-TEQ/kg bw. Only six months later the SCF carried out a re-evaluation of its t-TWI from November 2000. The reconsideration of 'pivotal studies' led to the situation that the re-assessment is now based only on rat studies which investigated only reproductive effects only on male offspring and, in addition, three of these studies are single dose studies at gestational day 15. Applying an overall uncertainty factor of 10 to the LOAEL derived estimated human daily intakes (EHDI) the SCF concluded that 14 pg/kg bw per week should be considered as a tolerable intake for 2,3,7,8-TCDD. The SCF stated that on a body weight basis, the dioxin intake of breast-fed infants has been estimated to be one to two orders of magnitude higher than the average adult intake. Recent German data suggest that the body burden of formerly breast-fed children aged 9-11 is still about 30% higher than those of their formula-fed age-mates. As breast-feeding has measurable benefits for neurological and immunological development, formula feeding cannot be recommended as an alternative to lower dioxin intake. So the only remaining way to lower the dioxin uptake is to drastically reduce the background exposure of the general population. It is acknowledged that any recommendation of a precise number for a TDI is flawed by uncertainties and the possibility of different weight being given to the studies of relevance. The determination of the TDI has influence on all regulatory limit values that are based on the TDI value. A higher TDI lowers the level of protection for humans. It is proposed by the German Federal Environmental Agency that the TDI should be reassessed in a process transparent to the public and on the basis of all relevant endpoints from animal experiments and human epidemiology, including the assessment of cancer risks.     

Organochlorines in different fractions of sediments and in different planktonic compartments of the Belgian continental shelf and the Scheldt estuary

PCB levels in sediments (bulk and fraction <63 microm), suspended matter and zooplankton from the Belgian continental shelf of the North Sea and the Scheldt estuary were evaluated in relation to their organic carbon content, their lipid content and, for sediments, their particle size distribution. PCB accumulation mechanisms are discussed, considering the importance of direct contamination (adsorption onto the cell surfaces, absorption through the cell walls and partitioning into the cell lipids) for suspended matter and sediments, and of indirect contamination through the food for zooplankton. Geographical and seasonal variations are described.     

Abundance and sources of ambient dioxins in Hong Kong: a review of dioxin measurements from 1997 to 2001

Ambient measurements of seventeen 2,3,7,8-polychlorinated dibenzo-p-dioxin/dibenzofuran congeners (2,3,7,8-PCDD/Fs) have been taken in a number of monitoring programs or ad-hoc studies in Hong Kong. The longest monitoring program started at two locations in the territory in July 1997. The other monitoring efforts are ad-hoc studies, varying from a few coordinated sampling events at multiple sites to a year-long monitoring project that targeted suspected local dioxin sources. In this paper, we examined these measurements to understand the ambient levels, temporal and spatial variation, and possible sources of the 2,3,7,8-PCDD/Fs in Hong Kong. The territory-wide annual average concentration of the dioxins was 0.052 pg I-TEQ/m3 measured at the regular monitoring stations in the most recent annual cycle of 2000/2001. This level fell at the lower end of the range of dioxin concentrations measured at other urban locations around the world. The dioxin levels showed a clear seasonality in that elevated concentrations were observed in the winter and lower concentrations in the summer at all monitoring sites with one year or more regular measurements. The measurements indicated that the few known local dioxin sources, including a major chemical waste incinerator facility, landfill sites, and vehicular traffic, are not important contributors to ambient dioxins in Hong Kong. On days of high dioxin concentrations, the 2,3,7,8-PCDD/F congeners were observed to have almost identical compositions with a north-northwest to south-southeast spatial gradient in concentrations at different sampling locations in Hong Kong. This observation, along with other collaborative evidence, established a strong link between high dioxin concentration days in Hong Kong and regional transport of the polluted air masses from the north.     

Food contamination control in European new Member States and associated candidate countries: Data collected within the SAFEFOODNET project

This paper reports the results obtained from the data collected within the European Commission funded project SAFEFOODNET regarding the state of the art in the control of chemical food contaminants in twelve European New Member States and one Associated Candidate Country (Turkey). Information has been gathered on institutions involved in food chemical contamination control, types of contaminants and matrices analyzed, procedures for data quality assurance, purposes of the analyses and accessibility of data in the participant countries. The resulting picture points out the general availability of adequate capabilities for the analysis of food contaminants in the laboratories in charge of control and the performance of the analysis of a large variety of chemicals (persistent organic pollutants, polycyclic aromatic hydrocarbons, pesticides, mycotoxins, heavy metals, radionuclides) in almost each country with few exceptions (dioxins in Bulgaria, Turkey, Latvia, persistent organic pollutants in Lithuania and Malta, polycyclic aromatic hydrocarbons in Malta). The application of validated analytical methods and the process of laboratory accreditation are partially fulfilled within the investigated countries, but still forthcoming for some countries, as in Romania, Turkey and Malta. Information collected on food controls is only partially available online and the language used is prevalently local and English to a lesser extent.     

Fourth WHO-coordinated survey of human milk for persistent organic pollutants (POPs): Belgian results

Persistent organic pollutants (POPs) are chemicals that accumulate in the food chain and are toxic to humans and wildlife. The fourth World Health Organization (WHO) survey on POP levels in human milk (2006-2009) aims to provide baseline and trend information on human exposure to POPs. So far Belgium participated in all three previous rounds (1988, 1992, 2001). Whereas the first three rounds focused on determination of dioxins and PCBs in pooled (mixed) samples, the fourth survey comprised the analyses of individual milk samples for nine "basic POPs" (chlorinated pesticides and indicator PCBs) and of pooled milk samples for "basic POPs", "advanced POPs" (dioxins and dioxin-like PCBs) and "optional POPs" (polybrominated diphenylethers [PBDEs], polybrominated dioxins and dibenzofurans [PBrDD/F], mixed halogenated dioxins and dibenzofurans [PXDD/F] and hexabromocyclododecane [HBCD]). For the Belgian participation human milk samples were collected during the summer of 2006 from 197 women between 18 and 30 years old distributed over all Belgian provinces. The individual samples were analyzed in a Belgian Laboratory for "basic" POPs. A pooled sample was made from 178 individual samples and analyzed by the WHO Reference Laboratory for the "basic, advanced and optional" POPs. The results indicate that most organochlorinated pesticides banned 25-30 years ago were below or around detection limits in Belgian human milk samples although DDE was still found at low levels in all samples. Over the last five years the levels of marker PCBs and PCDD/Fs in Belgian human milk decreased, respectively, by 58% and 39%. For some of the other emerging or older compounds recent international data are needed to allow comparison. This shows the importance of international studies as run by WHO.     

The emission inventory of PCDD/PCDF in Taiwan

Establishment of a country or region-based dioxin inventory was considered a crucial step toward elimination of worldwide dioxins/POPs contaminations, although no harmonized method for the preparation of an inventory is available at present. In this study, we used limited data and information to generate an inventory of dioxin emissions from some major sources in Taiwan. A total of 67.25 g I-TEQ of dioxins released annually was estimated. Unlike most of the industrialized countries, municipal waste incineration is not the highest contributor for dioxins released into the atmosphere. In contrast, secondary copper smelting accounts for more than 39% of the total dioxin emissions, and is higher than those from all waste incinerators combined (23.7%). Cement kilns and electric arc furnaces for steels also produced significant portion (both >10%) of dioxins into the environment, followed by secondary aluminum smelting (6.53%), industrial oil combustion (5.02%) and power plants fueled by coal (5.01%). Other known sources are either insignificant with respect to their dioxin emissions or not included in this inventory due to lack of information or uncertainty of the results. Data presented in this report provide a general picture of dioxin emissions in Taiwan, but were mostly based on less reliable or representative information, especially with respect to emission factors from different emission sources. It is necessary to establish background information relative to our own environment at present. Upon available, the inventory should be updated accordingly for proper environmental management on dioxins.     

A worldwide survey of polychlorinated dibenzo-p-dioxins, dibenzofurans, and related contaminants in butter

The main source of human exposure to persistent organic pollutants (POPs) is, in general, food. In this study, 64 butter samples from 37 countries were analyzed to assess the global contamination of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), hexachlorobenzene (HCB), and 2,2-bis (4-chlorophenyl)-1,1,1-trichloroethane (DDT) together with its major metabolites. The objectives of the study were to assess the presence of major organohalogen contaminants in butter, to trace geographical differences, and to determine toxic equivalents (TEQs) of PCDDs/Fs and dioxin-like PCBs in butter. The highest PCDD/F concentrations were found in butter from Korea with an average of 1.4 pg TEQ g(-1) lipid weight (l.w.). from PCDD/F and an additional contribution from the non- and mono-ortho-PCBs of 0.55 pg TEQ g(-1) l.w. Belgian butter showed average levels of 0.53 and 1.2 pg TEQ g(-1) l.w. for PCDDs/Fs and PCBs, respectively, but one sample of Belgium butter had a total TEQ level as high as 4.0 pg TEQ g(-1) l.w. Three out of five butter samples from Portugal showed similarly high PCDD/F TEQ levels. The sigmaPCB levels in European butter appeared to be somewhat higher than in the samples from the rest of the world. The average contribution of CB-153 to the total PCB concentration was 22% (SD 6.4, coefficient of variation 29%). Generally, the PCBs contributed around 60% of the total TEQ value, with CB-126 contributing approximately half of this value. This shows the important TEQ contribution from dioxinlike PCBs to the total TEQs. The highest HCB levels were found in butter samples from Russia, Ukraine, Belgium, and Slovenia. Low levels of HCB in butter were generally found in the Southern Hemisphere. Butter samples from countries from Eastern Europe had elevated sigmaDDT concentrations, with a particularly high concentration in Ukraine butter, followed by some Russian samples, Brazil, and the U.S.