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Recent trends suggest that cocaine smugglers have become more and more inventive to avoid seizures of large amounts of cocaine transported between countries. We report a case of a mail parcel containing a dance pad which was seized at the Customs Department of Brussels Airport, Belgium. After investigation, the inside of the dance pad was found to contain a thick polymer, which tested positive for cocaine. Analysis was performed using a routine colorimetric swipe test, gas chromatography coupled with mass spectrometry and nuclear magnetic resonance spectroscopy. The polymer was identified as polyvinyl alcohol (PVA) and contained 18% cocaine, corresponding to a street value of € 20,000. Laboratory experiments showed that cocaine could be easily extracted from the PVA matrix. This case report reveals a new smuggling technique for the transportation of large amounts of cocaine from one country to another. [ABSTRACT FROM AUTHOR]

sensitive hydrophilic interaction liquid chromatography (HILIC)-tandem mass spectrometry method was developed and validated for the analysis of 13 pharmaceuticals (omeprazole, pantoprazole, ranitidine, citalopram, fluoxetine, paroxetine, venlafaxine, tramadol, nebivolol, metoprolol, atenolol, bisoprolol and metformin) in influent wastewater. The analytes were selected from the list of top-sold prescription pharmaceuticals in Belgium. The HILIC separation was optimised to achieve quantification of all analytes in real influent wastewater samples where other compounds, mainly metabolites of some of the pharmaceuticals, were found to interfere even with mass-spectrometric detection in multiple reaction monitoring (MRM) mode. Sample cleanup and preconcentration was based on solid-phase extraction, and Oasis HLB cartridges were chosen after optimization. The method was validated by assessing the following parameters: specificity, selectivity, lower limit of quantification (LLOQ), linearity, accuracy, precision, recovery and matrix effects. For each analyte, LLOQs were sufficiently low to provide a good analytical performance at concentrations expected in real influent samples. Typical LLOQs were 1 ng/L, except for metformin (500 ng/L). Six deuterated analogues were used as internal standards. A total of 22 influent wastewater samples collected from 18 different wastewater treatment plants in Belgium were analysed. Most analytes were present in the samples at concentrations above the LLOQ and were in agreement with other results from the literature. Nebivolol was for the first time found in influent wastewater. In the future, this analytical method will be used to determine if there is a relationship between pharmaceutical sales figures and concentrations of these compounds in influent wastewater. [ABSTRACT FROM AUTHOR]

Aims Cocaine is the second most-used illicit drug world-wide and its consumption is increasing significantly, especially in western Europe. Until now, the annual prevalence has been estimated indirectly by means of interviews. A recently introduced and direct nation-wide approach based on measurements of the major urinary excreted metabolite of cocaine, benzoylecgonine, in wastewater is proposed. Design Wastewater samples from 41 wastewater treatment plants (WWTPs) in Belgium, covering approximately 3 700 000 residents, were collected. Each WWTP was sampled on Wednesdays and Sundays during two sampling campaigns in 2007–08. Samples were analysed for cocaine (COC) and its metabolites, benzoylecgonine (BE) and ecgonine methylester (EME) by a validated procedure based on liquid chromatography coupled with tandem mass spectrometry. Concentrations of BE were used to calculate cocaine consumption (g/day per 1000 inhabitants) for each WWTP region and for both sampling campaigns (g/year per 1000 inhabitants). Findings Weekend days showed significantly higher cocaine consumption compared with weekdays. The highest cocaine consumption was observed for WWTPs receiving wastewater from large cities, such as Antwerp, Brussels and Charleroi. Results were extrapolated for the total Belgian population and an estimation of a yearly prevalence of cocaine use was made based on various assumptions. An amount of 1.88 tonnes (t) per year [standard error (SE) 0.05 t] cocaine is consumed in Belgium, corresponding to a yearly prevalence of 0.80% (SE 0.02%) for the Belgian population aged 15–64 years. This result is in agreement with an earlier reported estimate of the Belgian prevalence of cocaine use conducted through socio-epidemiological studies (0.9% for people aged 15–64 years). Conclusions Wastewater analysis is a promising tool to evaluate cocaine consumption at both local and national scale. This rapid and direct estimation of the prevalence of cocaine use in Belgium corresponds with socio-epidemiological data. However, the strategy needs to be refined further to allow a more exact calculation of cocaine consumption from concentrations of BE in wastewater. [ABSTRACT FROM AUTHOR]

Abstract: Cocaine abuse, a growing social problem, is currently estimated from population surveys, consumer interviews and crime statistics. A new approach based on the analysis of cocaine (COC) and metabolites, benzoylecgonine (BE) and ecgonine methyl ester (EME), in water samples was applied to 28 rivers and 37 waste water treatment plants in Belgium using solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry. While EME was undetectable, COC and BE were detectable with concentrations ranging from <1 to 753ng/L and <1 to 2258ng/L, respectively. BE concentrations were employed to calculate the local amount of abused cocaine. The highest values (up to 1.8g/day cocaine per 1000 inhabitants) were found in large cities and during weekends. The estimation of cocaine abuse through water analysis can be executed on regular basis without cooperation of patients. It also gives clear geographical information, while prevention campaigns can easily be implemented and evaluated. [Copyright &y& Elsevier]

Although the contamination of wooden art objects with pesticides is well known, to the authors' knowledge no attempt has yet been made to investigate the eventual presence of other toxic compounds that have been produced during the degradation of pesticides or that may be present in the technical formulations. Here, the authors report on the presence of polychlorinated biphenyls (PCBs) and polychlorinated terphenyls (PCTs) in scrapings from wooden antique art objects, namely printing blocks, sculptures, and masks. These antiques belong to 2 fine art museums in Belgium—Antwerp's Ethnographic Museum and the Plantin-Moretus Museum. It is documented that these art objects were treated with pesticides in the 1950s. In addition, 2-heptachlorodibenzo-p-dioxin (HpCDD) isomers and octachlorodibenzo-p-dioxin (OCDD) were also identified. The presence of these toxic compounds in these antiques requires a better understanding of safety for the persons (conservators, museum employees, restorers, and visitors) coming in contact with these objects. [ABSTRACT FROM AUTHOR]

Abstract: Bisphenol-A (BPA), Triclosan (TCS) and Tetrabromobisphenol-A (TBBPA) are phenolic organic contaminants used in a variety of household applications. Through manufacture and usage, these contaminants can leach into the environment and can be detected in indoor dust. In this study, we determined the concentrations of BPA, TCS and TBBPA in indoor dust samples from 18 houses and 2 offices in Flanders, Belgium. The analysis was performed using solid–liquid extraction, clean-up and measurement by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Median concentrations of the 18 domestic dust samples were 1460, 220 and 10ngg−1 dust for BPA, TCS and TBBPA, respectively. Concentrations in offices were almost 5–10 times higher for BPA and TBBPA, while TCS concentrations were comparable at both locations. An assessment of the daily intake of these contaminants through dust was made and the contribution of dust to the total human exposure was calculated. For all three contaminants, dust seems to be a minor contributor (<10% of total exposure) to the total daily exposure. Food intake appears to be the major source of human exposure to BPA and TBBPA as dermal uptake through personal care products seems to be the major contributor for TCS. [Copyright &y& Elsevier]

A food market-basket, representative for the general Belgian population, containing various meat, fish and dairy food products, was analysed for its polychlorinated biphenyl (PCB) content. Additionally, fast food samples were also investigated. Based on the measured PCB levels (sum of 23 congeners), an average daily dietary intake estimate of PCBs was calculated. Of all foods analysed, fish had the highest average sum of PCB levels (7.1ng/g ww), with a high variation between the investigated species, followed by dairy products and eggs (3.2ng/g ww), fast food (1.9ng/g ww) and meat products (0.62ng/g ww). One fresh salmon filet had the highest total concentration of PCBs (36ng/g ww or 200ng/g lw), whereas levels in steak and chicken breast were the lowest of all foods analysed. PCB intake calculations were based on the average daily food consumption in Belgium and were estimated between 404 and 535ng/day of total PCBs (lower and upper bound). This value is in accordance with what was previously reported for diets from geographical distinct areas. Although it is only a minor constituent of the Belgian diet, fish is the major contributor to the total daily PCB intake (around 50%) due to the high PCB levels in this type of food. Meat products account for around 20% of the total dietary intake of PCBs, while dairy products and eggs contribute to a lesser degree (less than 20%). [Copyright &y& Elsevier]

Abstract: A food market-basket, representative for the general Belgian population, containing various meat, fish and dairy food products, was assembled and analysed for its polybrominated diphenyl ether (PBDE) content. Additionally, fast food samples were also investigated. Based on the measured PBDE levels, an average daily dietary intake estimate of PBDEs was calculated. Of all foods analysed, fish had the highest average sum of PBDE levels (BDEs 28, 47, 99, 100, 153, 154, and 183; 460 pg/g ww), followed by dairy products and eggs (260 pg/g ww), fast food (86 pg/g ww) and meat products (70 pg/g ww). One fresh salmon filet had the highest total concentration of PBDEs (2360 pg/g ww), whereas levels in steak and chicken breast were the lowest of all foods analysed. BDE 209 was never found above LOQ in any food. PBDE intake calculations were based on the average daily food consumption in Belgium and were estimated between 23 and 48 ng/day of total PBDEs (lower and upper bound). This value is in accordance with what was previously reported for diets from geographical distinct areas, such as Canada, Finland, Spain, Sweden and the UK. Although it is only a minor constituent of the Belgian diet, fish is the major contributor to the total daily PBDE-intake (around 40%) due to the high PBDE levels in this type of food. Although low contaminated, meat products account for around 30% of the total dietary intake of PBDEs. Dairy products and eggs contribute to a lesser degree (less than 30%). [Copyright &y& Elsevier]

Background: In recent years, scientific evidence has emerged that wastewater-based epidemiology can deliver complementary information concerning the use of different substances of abuse. In this study, the potential of wastewater-based epidemiology in monitoring spatial and temporal trends in alcohol consumption in different populations in Belgium has been examined.Methods: Concentrations of ethyl sulphate, a minor Phase-II metabolite of ethanol, in 163 influent wastewater samples from eight wastewater treatment plants in Belgium in the period 2013-2015 were measured with liquid chromatography coupled to tandem mass spectrometry and used to estimate alcohol consumption.Results: The highest levels of alcohol consumption were detected in the metropoles Antwerp and Brussels compared to smaller villages. Annual variations were detected, with a higher alcohol consumption measured in 2013 compared with 2014. The weekly pattern showed a clear week and weekend difference in alcohol use, with intermediate levels on Monday and Friday. The results were extrapolated and a use of 5.6L pure alcohol per year per inhabitant aged 15+ has been estimated in Belgium. The comparison with available information on drinking habits of the Belgian population further demonstrated the usefulness of the wastewater-based epidemiology approach.Conclusions: This is the largest wastewater-based epidemiology study monitoring alcohol consumption to date, demonstrating that objective and quick information on spatio-temporal trends in alcohol consumption on a local and (inter)national scale can be obtained. [ABSTRACT FROM AUTHOR]

Abstract: Bisphenol-A (BPA) is a commonly used color developer in thermal paper. In this application, BPA is present in its free, unbound form and can be readily released, making thermal paper a potential source for human exposure. In this study, BPA was determined in 44 thermal paper samples collected in Belgium. BPA was detected in all the samples; 73% of the samples had concentrations between 0.9% and 2.1% (between 9 and 21mg BPA/g paper), while the remaining 27% of the samples had concentrations below 0.01% (0.1mg BPA/g paper). The BPA concentrations measured in thermal paper were comparable with those reported in other international studies. Since thermal paper is a feedstock for paper recycling processes, contamination of other “BPA-free” papers can occur. An estimation of human exposure through thermal paper results in a median intake of 445ng BPA/day for the general population, which corresponds to an exposure of 6.4ng/kg bw/day for a person of 70kg. The exposure of those people who come occupationally in contact with thermal paper can be much higher. [Copyright &y& Elsevier]

Abstract: Concentrations of several “novel” brominated flame retardants (NBFRs) are reported in indoor dust samples from Belgian houses (n =39) and offices (n =6) and from day-care centers and schools in the West Midlands of the UK (n =36). Using a GC-ECNI/MS method, the following NBFRs were quantified: decabromodiphenyl ethane (DBDPE) (range <20–2470ngg−1), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) (range <0.5–1740ngg−1), tetrabromobisphenol A-bis(2,3-dibromopropylether) (TBBPA-DBPE) (range <20–9960ngg−1), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB) (range <2–436ngg−1) and bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH) (range <2–6175ngg−1). Hexachlorocyclopentadienyl-dibromocyclooctane (HCDBCO), another NBFR, was below the detection limit of 2ngg−1 dust in all dust samples. No correlation was detected between concentrations of NBFRs and PBDEs. The ratio of TBB:TBPH in the dust samples ranged from 0.01 to 4.77 (average 0.42), compared to the ratio present in the commercial flame retardant product FM 550 (TBB:TBPH=4:1). Furthermore, no correlation was detected between concentrations in dust of TBB and TBPH. This may suggest different sources of these NBFRs, or similar sources but compound-specific differences in their indoor fate and transport. Exposure via dust ingestion was estimated for both adults and toddlers under low-end (5th percentile), typical (median), and high-end (95th percentile concentrations) scenarios. These were calculated assuming 100% absorption of intake dust and using mean dust ingestion (adults=20mgd−1; for toddlers=50mgd−1) and high dust ingestion (adults=50mgd−1; for toddlers=200mgd−1). Typical exposure with high dust ingestion estimates for adults were 0.01, 0.2, 0.01, 0.02 and 0.08ngkg−1 bw d−1 and for toddlers 0.05, 1.9, 0.08, 0.4 and 1.12ngkg−1 bw d−1 for BTBPE, DBDPE, TBB, TBPH and TBBPA-DBPE, respectively. Our results showed that, similar to PBDEs, toddlers have higher exposure to NBFRs than adults. This study documents the presence of NBFRs in indoor environments, and emphasizes the need to evaluate the health implications of exposure to such chemicals. [Copyright &y& Elsevier]

Abstract: The sewage epidemiology approach was applied to a one-year sampling campaign in the largest wastewater treatment plant (WWTP) in Belgium. The consumption of cocaine (COC), amphetamine (AMP), methylenedioxymethamphetamine (MDMA), methamphetamine (METH), methadone (MTD) and heroin (HER) was evaluated based on measured concentrations of the parent compound and/or metabolites in daily 24-hour composite influent wastewater samples. The inevitable back-calculations used in the sewage epidemiology approach were adapted to newly available information regarding the stability of the compounds in wastewater and the excretion pattern of illicit drugs. For COC, three different back-calculation approaches were evaluated. In addition, for the first time, efforts were made to calculate the number of inhabitants living in the catchment area of the WWTP in a real-time and dynamic way, based on concentrations of nitrogen, phosphorus and oxygen in the wastewater samples. Clear variations in the amount of inhabitants in the catchment area of the WWTP were observed. For COC, AMP and MDMA a significant higher weekend use was observed while for HER and MTD no significant daily variations could be found. METH consumption was negligible. Generally, the sewage epidemiology calculations were in agreement with official statistics. This manuscript shows that sewage epidemiology provides consistent and logical results and that it is a promising tool that can be used in addition to classical studies to estimate illicit drug use in populations. Therefore, efforts should be made to further optimize this approach in the future. [Copyright &y& Elsevier]

Human exposure to mixtures of polychlorinated biphenyls (PCBs) may result in the formation of different profiles of hydroxylated PCBs (HO-PCBs), as a consequence of different exposures or dissimilar metabolism of parent compounds. Therefore, we investigated the levels and profiles of PCBs and HO-PCBs in human serum samples collected from two European countries with different degrees of pollution. There was no significant difference between the levels of sum PCBs measured in each set of samples, with a median concentration of 3100 pg/mL for Romanian samples (n = 53) and 3380 pg/mL for Belgian samples (n = 22). However, the median concentrations recorded for sum HO-PCBs were almost double in Belgian (310 pg/mL) compared to Romanian (175 pg/mL) samples. The detection frequency recorded for HO-PCBs in Belgian samples was also significantly higher compared to Romanian samples. The main contributors to the sum HO-PCBs in the Belgian samples were 4HO-CB107 > 4HO-CB146 > 4HO-CB187 (76% from the sum HO-PCBs) and 4HO-CB187 > 4HO-CB146 > 3'HO-CB138 (66% from the sum of HO-PCBs) in the Romanian samples. The HO-PCB profile showed that the higher chlorinated HO-PCBs had a higher contribution in the Romanian samples compared to the Belgian ones. This suggests that differences in the PCB profiles between populations can lead to the formation of different HO-PCB metabolite profiles presenting thus different risks for populations. No clear preferential mechanism of HO-PCB metabolite formation (HO-direct insertion vs. 1,2-shift of a chlorine atom) could be highlighted for investigated samples. The main chlorinated phenolic compound found in the Belgian samples was pentachlorophenol (PCP) which accounted for up to 85% of the total quantified phenolics, whereas in the Romanian samples, PCP accounted for only 35%. [ABSTRACT FROM AUTHOR]

Human exposure to individual polychlorinated biphenyl (PCB) congeners and dichloro-diphenyldichloroethylene (p,p'-DDE) through food (duplicate diets) and indoor dust ingestion was assessed for 19 Belgian students. The serum concentrations of the persistent PCB congeners in serum (PCB 118, 138, 153, 170, and 180) have been correlated with the individual intake through food and dust. Dietary intakes of ΣPCBs ranged between 40 and 204 ng/day (median 133). PCB exposure through dust ingestion ranged between 0.1 and 0.8 ng/day (median 0.3) or 0.3 and 1.7 ng/day (median 0.8), assuming average dust ingestion (20 mg/day) and high dust ingestion rates (50 mg/day), respectively. Dietary intake of p,p'-DDE was comparable to that of PCBs with a range from 21 to 214 ng/day (median 92). The exposure to p,p'-DDE via dust ingestion ranged between 0.02 and 0.43 ng/day (median 0.17) or 0.05 and 1.09 ng/day (median 0.43), assuming average and high dust ingestion rates, respectively. Concentrations measured in blood serum were 28-153 ng/g lipid weight (lw) (median 74) and 32-264 ng/g lw (median 45) for ΣPCBs and p,p'-DDE, respectively. Serum concentrations in the studied population are slightly lower compared to other European populations. In spite of the uncertainty associated with the dust ingestion rates, food was the predominant exposure pathway for each PCB congener and for p,p'-DDE in the studied population. Food intake contributed more than 99% of the combined PCB intake from food and dust. No significant positive correlations (p > 0.05) were observed between the serum concentrations of PCBs and p,p'-DDE and the total intake through food and dust for each participant. Instead, it is hypothesized that past and episodic higher current intakes are more important determinants of body burden than continuous background exposures at low levels. [ABSTRACT FROM AUTHOR]

Abstract: The extent and the sources of contamination with brominated flame retardants (BFRs), such as polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD), in home-produced eggs from free-foraging chicken of Belgian private owners were investigated. Various factors, such as seasonal variability, exposure of chickens through diet (kitchen waste) and soil, and elimination of BFRs through eggs and faeces were assessed. PBDEs were more important than HBCD in terms of concentrations and detection frequency. Concentrations of PBDEs and HBCD in Belgian home-produced eggs were relatively low and comparable with reported levels from other European countries and the US. The concentrations of PBDEs (sum of 13 congeners, including BDE 209) ranged between not detected and 32 ng/g lipid weight (lw), with medians of 3.0 and <2.0 ng/g lw for the autumn 2006 and spring 2007 campaigns, respectively. When present, BDE 209 was the major PBDE congener (45% of sum PBDEs). When BDE 209 was not detected, the PBDE profile was composed of PentaBDE (BDE 99 and BDE 47), with, in some cases, higher contribution of OctaBDE (BDE 183 and BDE 153). HBCD was also detected (<0.4 and 2.9 ng/g lw for the autumn 2006 and spring 2007 campaigns, respectively), but at lower detection frequency. The highest HBCD value was 62 ng/g lw. The similarity between profiles and seasonal variations in the concentrations of BFRs in soil and eggs indicate that soil is an important source, but not the sole source, for eggs laid by free-foraging chicken. The contamination of eggs with PBDEs and HBCD appears to be of low concern for public health and the contribution of eggs to the total daily intake of PBDEs appears to be limited (10% for chicken owners and 5% for the average Belgian consumer). [Copyright &y& Elsevier]

Human exposure to polybrominated diphenyl ethers (PBDEs) through food and indoor dust ingestion was assessed for 19 Belgian adults. The intake of PBDEs (Σtri-hepta BDEs and BDE 209) in the studied population is influenced mainly by diet. Dietary intakes of Σtri-hepta BDEs (BDEs 28, 47, 99, 100, 153, 154, and 183) were 5.9-22.0 ng/day (median 10.3), while those via dust ingestion were 0.1-1.4 ng/day (median 0.25) or 0.3-3.5 ng/day (average 0.6), assuming dust ingestion rates of 20 and 50 mg/day, respectively. Dietary intakes of BDE 209 were 50-238 ng/day (median 95), whereas those via dust ingestion were 0.4-11 ng/day (median 1.8) or 1.0-29 ng/day (median 4.6) for dust ingestion rates of 20 and 50 mg/day, respectively. It is important to acknowledge the uncertainty associated with the dust ingestion rates. Concentrations of Σtri-hepta BDEs measured in blood serum were 0.9-7.2 ng/g lipid weight (lw) (median 1.9). This is similar to other European populations, but lower than for nonoccupationally exposed Americans (average of 19 ng/g lw). When compared with estimates of exposure via both dietary and indoor dust ingestion for Americans, the exposures reported here are consistent with the hypothesis that the difference between European and American body burdens of PBDEs is attributable primarily to greater exposure via dust ingestion for Americans. The total intake of PBDEs through food and dust for each participant could not be correlated with the corresponding serum concentration. Instead, it is hypothesized that past and episodic current higher intakes of PBDEs are more important determinants of body burden than continuous background exposures at the low levels measured in this study. [ABSTRACT FROM AUTHOR]

Estimates of cocaine consumption are currently resulting from population surveys, consumer interviews and crime statistics. A new approach (“sewage epidemiology”) based on the analysis of cocaine (COC) and its metabolite, benzoylecgonine (BE), in water samples was applied to 10 river sites and 30 wastewater treatment plants (WWTPs) in Belgium. Each river site was sampled twice, during the summer of 2007 and the winter of 2007–2008, while each WWTP was sampled on a Sunday and a Wednesday, during the summer–autumn of 2007 and the winter of 2007–2008. This sampling strategy allowed for the evaluation of spatial and seasonal variations in the occurrence of COC and BE in waste- and surface water. WWTP Brussel-Noord was sampled for 19 consecutive days to evaluate daily and weekly variations in the presence of COC and BE in wastewater. For 7 WWTPs, influent and effluent water samples were collected to investigate the removal of COC and BE during the wastewater treatment process. Analysis of water samples was performed using solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry. Measured concentrations were further converted into an amount of used cocaine, called cocaine equivalents, as previously described in the literature. Results showed no significant difference in cocaine use between the investigated seasons. A constant cocaine consumption was observed during the week (Monday–Friday) with peaks during the weekend for WWTP Brussel-Noord. The COC/BE ratio in water samples was significantly higher during winter, most probably due to a slower hydrolysis of cocaine in low-temperature water. COC and BE were removed in the investigated WWTPs with a removal efficiency of >93%. [Copyright &y& Elsevier]

Abstract: Levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), and polychlorinated biphenyls (PCBs) were measured in several fish species originating from the river Scheldt (Belgium). Five sampling locations were chosen in a highly industrialized area along the river, while two ponds in the vicinity of the river served as reference sites. The present study is a follow-up of a survey performed in 2000 which reported extremely high levels of PBDEs and HBCDs in eel (Anguilla anguilla) collected from the same region (Oudenaarde, Flanders). The sum of tri- to hepta-BDE congeners (2270±2260 ng/g lipid weight (lw), range 660–11500 ng/g lw) and total HBCDs (4500±3000 ng/g lw, range 390–12100 ng/g lw) were one order of magnitude higher than levels usually reported from freshwater systems, indicating the presence of point sources. In most samples, levels of total HBCDs were higher than those of PBDEs, probably due to the high density of factories using HBCD as an additive brominated flame retardant (BFR). The high values of HBCDs were confirmed by both gas- and liquid-chromatography–mass spectrometry. Although BFR levels were between the highest ever reported in freshwater ecosystems, PCBs could be detected at even higher concentrations (16000±14300 ng/g lw, range 3900–66600 ng/g lw), being among the highest levels recorded in Belgium. The inter-sampling site variation of PBDEs, HBCDs and PCBs was comparable. All locations presented similar PBDE congener profiles, with BDE 47 being the dominant congener, followed by BDE 100, BDE 99 and BDE 49, probably originating from the former use of the penta-BDE technical mixture. In order to estimate the impact of these point sources on human exposure, we further focussed on eels which showed a considerable decrease in the PBDE and HBCD levels between 2000 and 2006. Due to the wide span in concentrations between the different sampling locations, a variable contribution to the total human exposure through local eel consumption was estimated. The calculated daily intake ranged from 3 ng to 330 ng PBDEs/day for normal eel consumers, but was as high as 9800 ng PBDEs/day for anglers, which may be considered at risk. [Copyright &y& Elsevier]

In January 1999, 50kg polychlorinated biphenyls (PCBs) contaminated with 1g dioxins were accidentally added to a stock of recycled fat used for the production of 500tonnes animal feed in Belgium. Although signs of poultry poisoning were noticed by February 1999, the extent of the contamination was publicly announced only in May 1999, when it appeared that more than 2500 poultry and pig farms could have been involved. This has resulted in a major food crisis, known worldwide as the “Belgian PCB/dioxin crisis”. The crisis was resolved by the implementation of a large food monitoring program for the seven PCB markers (PCBs 28, 52, 101, 118, 138, 153 and 180). When PCB concentrations exceeded the tolerance levels of 100, 200 or 1000ng/g fat for milk, meat or animal feed, respectively, the 17 toxic polychlorinated dibenzodioxins and furans (PCDD/Fs) congeners were also determined. By December 1999, more than 55,000 PCB and 500 dioxin analyses were already done by Belgian and international laboratories. The highest concentrations of PCBs and dioxins and the highest percentage of affected animals were found in poultry. Several important consequences of the food crisis were: (1) the introduction in 1999 of norms for PCBs in feedstuffs and food in Belgium followed by the introduction in 2002 of European harmonized norms for PCDD/Fs in animal feed and food of animal origin; (2) the systematic national monitoring of food of animal origin; and (3) the creation of the Federal Agency for Food Safety in Belgium. The human health risk following this major incident was assessed with contradictory results. It was suggested that, since only a limited proportion of the food chain was contaminated, it is unlikely that adverse effects were inflicted in the Belgian population. However, another assessment suggests that neurotoxic and behavioural effects in neonates, together with an increase in the number of cancers, may be observed. [Copyright &y& Elsevier]

Small-scale geographical variation in the occurrence of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) was investigated using the eggs of a terrestrial residential songbird species, the great tit (Parus major). In addition, we investigated the influence of the type of sampling location on the presence of these pollutants. To achieve this, 10 different sampling locations in Flanders (Belgium) were classified into 3 groups based on the extent of urbanisation, industrialisation and agriculture. The higher variance among sampling locations for the levels and profiles of PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. Levels of PCBs and PBDEs were significantly higher in the industrialised sampling locations compared to the other locations. Sum PCB and sum PBDE levels reached up to 6050 and 79 ng/g lipid weight, respectively. PCBs and PBDEs were highly positively correlated for all groups, suggesting similar exposure pathways and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs up to 2683 ng/g lipid weight) were detected in the rural sampling locations situated in a residential area. This suggests that local historical usage of OCPs by inhabitants may be an important source of contamination in Flanders. Contamination profiles differed also among the sampling locations. The rural sampling locations had a higher contribution of lower brominated BDE congeners, whereas the industrialised locations had a higher contribution of higher brominated congeners. The differences in contamination profiles among the sampling locations are probably due to differences in exposure. In conclusion, our results showed that the characteristics of a sampling location influence both the levels and profiles of PCBs, OCPs and PBDEs. [Copyright &y& Elsevier]