Polybrominated Biphenyls Research Articles

Brominated dioxins (PBDD/Fs) and PBDEs in marine shellfish in the UK

The occurrence of brominated dioxins (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) was investigated in commonly consumed species of marine shellfish in the UK. Individual samples of Pacific oysters (Crassostrea gigas), native oysters (Ostrea edulis), mussels (Mytilus edulis), scallops (Pecten maximus), and cockles (Cerastoderma edule) were collected from different coastal regions between 2006 and 2007. Samples of a particular species from each site were composited and 60 samples were analysed. Polybrominated dibenzofurans (PBDFs) occurred more frequently and generally at a higher level than polybrominated dibenzodioxins (PBDDs), except for 237-TriBDD, which was the predominant PBDD/F congener in some species, notably oysters. This profile may reflect the environmental distribution of these compounds and the effects of removal mechanisms, such as degradation, selective uptake and metabolism. PBDEs were detected in all samples. The dominant congeners were BDEs 47, 49, 99 and 100 and, to a lesser extent, BDEs 66 and 154. The occurrence of BDE-209 was observed in most samples and appears to be species selective, with the highest values occurring almost exclusively in mussels and cockles. Among the species studied, oysters and mussels displayed relatively higher levels of both sets of contaminants; native oysters, in particular, showed elevated levels of 237-TriBDD (up to 14.5 ng/kg). In general, contaminant levels appeared to be consistent with the extent of local industrialisation with lower levels observed in more remote areas such as the north of Scotland. Polybrominated biphenyls (PBBs) were also measured, and PBBs 49, 52 and 77 were the most frequently detected, although levels were very low. Dietary intakes, estimated for PBDD/Fs, showed that 237-TriBDD from single portions of oysters constituted a high proportion of the total dietary intake of the congener but, otherwise, dietary intakes of PBDD/Fs from shellfish were relatively low.

Reproductive and Developmental Toxicity of a Pentabrominated Diphenyl Ether Mixture, DE-71, to Ranch Mink (Mustela vison) and Hazard Assessment for Wild Mink in the Great Lakes Region

Polybrominated diphenyl ethers (PBDEs) are widespread persistent and bioaccumulative environmental contaminants. Recent scientific attention has focused on the developmental toxicity of PBDE commercial mixtures following perinatal exposure of rodents; however, these studies do not necessarily predict toxicity to highly exposed top predators, such as mink (Mustela vison). Here we assessed the effects of environmentally relevant doses (0, 0.1, 0.5, and 2.5 ppm [wt/wt] in feed) of a technical pentabrominated diphenyl ether mixture, DE-71, on reproductive performance of mink and on development of offspring exposed perinatally and post-weaning until 33 weeks. A dietary concentration that causes no effects on reproduction in rodents, 2.5-ppm DE-71, resulted in complete reproductive failure in these mink, while whelping rates were not affected at all lower does. Developmental effects in offspring were evident in 33-week-old juveniles, which were more sensitive to effects than their respective dams. Juvenile thyroid hormone homeostasis was also much more sensitive compared to rodents, and at 0.5-ppm DE-71, total triiodothyronine (T3) was significantly decreased in all males and females, even despite a compensatory increase of total thyroxine (T4) in females. T4-outer-ring deiodinase activity, mainly contributed by type II deiodinase, was not affected at any dose for any life stage, but thyroid follicular epithelium cell height was elevated in the 0.5-ppm-treated juveniles (p = 0.057). Ethoxyresorufin O-deethylase activity was significantly induced in all offspring at 33 weeks, most likely as a consequence of polybrominated dioxin, furan, or biphenyl impurities in DE-71. Biomonitoring of wild mink in the Great Lakes region indicated that most populations had lower concentrations than what are expected to affect thyroid hormone homeostasis, but margins of safety are small and mink around Hamilton Harbour exceeded the no observed adverse effect level for T3 disruption.

Brominated Flame Retardants in Children’s Toys: Concentration, Composition, and Children’s Exposure and Risk Assessment

Brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), and polybrominated biphenyls (PBBs) were found in children's toys purchased from South China. The median BFR concentrations in the hard plastic toys were 53,000, 5540 ng/g, 101.1 ng/g, and 27.9 ng/g, fortotal PBDEs, DBDPE, BTBPE, and PBBs, respectively,which were notably higher than values in other toys. The PBDE concentrations were below the threshold limit (1000 ppm) required bythe European Commission's Restriction of Hazardous Substances (RoHS) and Waste Electrical and Electronic Equipment (WEEE) directives in all of the toys, except for one hard plastic toy with a total PBDE concentration of 5,344,000 ng/g. The BFR profiles in the toys were consistent with the patterns of their current production and consumption in China, where PBDEs, specifically decaBDE product, were the dominant BFR, followed by the emerging DBDPE. The relatively high concentrations of octa- and nonaBDEs in the foam toys and the results of principal component analysis (PCA) may suggest the decomposition of highly brominated BDEs during the manufacturing processes of the toys. Daily total PBDE exposures associated with toys via inhalation, mouthing, dermal contact, and oral ingestion ranged from 82.6 to 8992 pg/kg bw-day for children of 3 months to 14 years of age. Higher exposures, predominantly contributed through the mouthing pathway, were observed for infants and toddlers than for the other subgroups. In most cases, children's BFR exposure via the toys likely accounts for a small proportion of their daily BFR exposure, and the hazard quotients for noncancer risk evaluation were far below 1. To the author's knowledge, this is the first study to examine the concentrations of BFRs in toys, and the potential exposures to children.

Determination of brominated flame retardants in electrical and electronic equipments with microwave-assisted extraction and gas chromatography–mass spectrometry

Determination of brominated flame retardants in electrical and electronic equipments (EEE) was achieved through microwave-assisted extraction (MAE) and gas chromatography–mass spectrometry. Polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) including mono-brominated through deca-brominated congeners were qualified and quantified with good linearity (0.9963–0.9998) and repeatability (RSD, 1.1–8.1%). Multivariable orthogonal experimental design was used to optimize the MAE parameters. Extraction temperature and time were the most significant factors for extraction process. The extractants were cleaned up with SPE method after extraction. Recoveries of spiked blank samples ranged from 72.4% to 108.4% for most of the analytes. The method was applied to the determination of PBBs and PBDEs in several kinds of real EEE samples. It was found that no detectable level of PBBs was detected among them. Different contents of PBDEs were tested in the tested samples and the total contents ranged from 25.0 ng g −1 to 194.0 ng g −1. The proposed approach demonstrated an environmentally friendly and convenient alternative, which only consumed 10 mL hexane to microwave extraction for 10 min at 100 °C.

Maternal exposure to a brominated flame retardant and genitourinary conditions in male offspring.

BackgroundThe upward trend in industrial nations in the incidence of male genitourinary (GU) conditions may be attributed to increased exposure to endocrine disruptors. Polybrominated biphenyl (PBB), a brominated flame retardant, is one such suspected endocrine disruptor.ObjectiveWe investigated the relationship between maternal serum levels of PBBs and GU conditions among male offspring exposed in utero.MethodsIn this cohort study of sons born to women accidentally exposed to PBBs during 1973–1974, we examined self-reported data on GU conditions among male offspring in relation to maternal serum PBB levels. We used generalized estimating equations to calculate odds ratios (ORs), controlling for gestational age at birth.ResultsOf 464 sons, 33 reported any GU condition (13 hernias, 10 hydroceles, 9 cryptorchidism, 5 hypospadias, and 1 varicocele). Four reported both hernia and hydrocele, and one both hernia and cryptorchidism. After adjustment for gestational age at birth, sons of highly exposed women (> 5 ppb) were twice as likely to report any GU condition compared with sons of the least exposed women [≤1 ppb; OR = 2.0; 95% confidence interval (CI), 0.8–5.1]. This risk was increased when we excluded sons born after the exposure but before the mother’s serum PBB measurement (OR = 3.1; 95% CI, 1.0–9.1). We found evidence of a 3-fold increase in reported hernia or hydrocele among sons with higher PBB exposure (test of trend p-value = 0.04). Neither hypospadias nor cryptorchidism was individually associated with PBB exposure.ConclusionsAlthough cryptorchidism and hypospadias were not associated with in utero PBB exposure, this study suggests that other GU conditions may be associated with exposure to endocrine-disrupting chemicals during development.

Assessing inter-generational transfer of a brominated flame retardant

Studies have shown that the lipophilic nature of polybrominated biphenyl (PBB) causes it to preferentially accumulate in breast milk posing a potential hazard for suckling infants. The purpose of this study was to examine the inter-generational transfer of PBB from mother to child and whether this association was modified by maternal breast-feeding patterns. One hundred and forty-five mother-child pairs that were participants of the Michigan Long-Term PBB Study were included in this analysis. Mothers were exposed to PBB via contaminated food between 1973 and 1974 and children were exposed in utero and for some, through breast-feeding. Seventy-three percent of children had a non-detectable serum PBB concentration (limit of detection (LOD) = 1 microg L(-1)). Mothers' serum PBB concentration at enrollment ranged from <LOD to 933 microg L(-1). The following variables were associated with the child having a detectable serum PBB concentration: maternal serum PBB > or =8 microg L(-1), breast-feeding > or =5.5 months, maternal age at child's birth > or =28 years, and being born during the PBB exposure period. Among mothers with a detectable serum PBB concentration, those who breast-fed > or =5.5 months were 6 times more likely to have a child with a detectable serum PBB concentration, compared to a non-breast-fed child (95% C.I., 2.0-19.6).

Octanol–air partition coefficients of polybrominated biphenyls

The octanol–air partition coefficients ( K OA) for PBB15, PBB26, PBB31, PBB49, PBB103 and PBB153 were determined as a function of temperature using a gas chromatographic retention time technique with 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (p,p′-DDT) as a reference substance. The internal energies of phase change from octanol to air ( Δ OA U) were calculated for the six compounds and were in the range from 74 to 116 kJ mol −1. Simple regression equations of log K OA versus relative retention times (RRTs) on gas chromatography (GC), and log K OA versus molecular connectivity indexes (MCI) were obtained, for which the correlation coefficients ( r 2) were greater than 0.985 at 283.15 K and 298.15 K. Thus the K OA values of the remaining PBBs can be predicted by using their RRTs and MCI according to these relationships.

Determination of polybrominated biphenyls in Tasmanian devils (Sarcophilus harrisii) by gas chromatography coupled to electron capture negative ion tandem mass spectrometry or electron ionization high‐resolution mass spectrometry

Two gas chromatography/mass spectrometry (GC/MS) methods for the determination of polybrominated biphenyls (PBBs) by isotope dilution analysis (IDA) using (13)C(12)-PBB 153 in the presence of polybrominated diphenyl ethers (PBDEs) were compared. Recovery of (13)C(12)-PBB 153 which was added to the extracted lipids before sample purification was commenced ranged from 88-117% (mean value 98.2 +/- 8.9%). Nevertheless, IDA analysis of PBBs using (13)C(12)-labelled congeners is limited by the potential co-elution of PBBs with polybrominated diphenyl ethers (PBDEs). The pair PBB 153 and BDE 154 was inspected since M(+) and [M-2Br](+) ions of (13)C(12)-PBB 153 and BDE 154 were only separated by 4 u. Gas chromatography/electron ionization high-resolution mass spectrometry with selected ion monitoring (GC/EI-HRMS-SIM) was suitable when m/z 475.7449 and m/z 477.7429 were used for (13)C(12)-PBB 153 because they are below the monoisotopic peak of the [M-2Br](+) fragment ion of hexaBDEs at m/z 479.7. Gas chromatography/electron capture negative ion tandem mass spectrometry selected reaction monitoring (GC/ECNI-MS/MS-SRM) measurements could be applied because (13)C(12)-PBB 153 and BDE 154 were separated by GC on a 25-m Factor Four CP-Sil 8MS column.Comparative measurements with GC/EI-HRMS-SIM and GC/ECNI-MSMS-SRM were carried out with samples of Tasmanian devils from Tasmania (Australia), an endangered species due to a virus epidemy which has already proved fatal for half of the population. Both techniques verified concentrations of PBB 153 in the range 0.3-11 ng/g lipids with excellent agreement of the levels in all but two samples. The PBB residue pattern demonstrated that PBB pollution originated from the previous discharge with technical hexabromobiphenyl which is dominated by PBB 153. Other congeners such as PBB 132 and PBB 138 were detected in the Tasmanian devils but the proportions relative to PBB 153 were lower than in the technical product. Samples of healthy and affected Tasmanian devils showed no significant difference in the PBB pollution level. The PBB concentrations in the Tasmanian devils were significantly below those causing toxic effects. On the other hand, PBB concentrations were one level or even higher than PBDEs.

Simultaneous preconcentration of a wide variety of organic pollutants in water samples: Comparison of stir bar sorptive extraction and membrane-assisted solvent extraction

Stir bar soptive extraction (SBSE) coupled to thermal desorption-gas chromatography–mass spectrometry (TD-GC–MS) and membrane-assisted solvent extraction (MASE) coupled to large volume injection-programmed temperature vaporisation-GC–MS (LVI-PTV-GC–MS) were optimised for the simultaneous determination of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalate esters (PEs), nonylphenols (NPs), polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) in water samples. In the case of SBSE-TD, variables affecting the extraction (extraction time, addition of sodium chloride or methanol and sample volume) and desorption (cryofocusing temperature, desorption time and temperature, vent pressure and desorption flow) were fitted for the simultaneous determination. The extraction solvent nature ( n-hexane, cyclohexane, n-heptane, ethyl acetate, toluene, dichloromethane or cyclohexane:ethyl acetate mixtures), as well as the addition of methanol (0–30%) and sodium chloride (0–20%), the extraction temperature (30–60 °C), shaking speed (250–750 rpm) and extraction time (5–150 min) were studied for the simultaneous membrane-assisted preconcentration. Finally, PTV-LVI variables such as injection volume (100–600 μL), injection speed (10–40 μL s −1), vent pressure (0–12.7 psi), vent time (0.05–0.8 min), vent flow (30–80 mL min −1), cryofocusing temperature (20–70 °C), split flow (20–100 mL min −1) and split time (1–5 min) were optimised. The optimisation was carried out by means of experimental design approaches in most of the cases. Precision (∼3–19% for both SBSE-TD and MASE-LVI-PTV), accuracy (∼80–120% for both SBSE-TD and MASE-LVI-PTV), limits of detection (LoDs) (0.1–222 ng L −1 for MASE-LVI-PTV and 0.03–20.4 ng L −1 for SBSE-TD in dependence of substance) and linearity (from 25 ng L −1 up to at least 500 ng L −1 for both procedures) were established for both procedures. Finally, the developed methods were applied to the determination of the free concentrations of PAHs, PCBs, PEs, NPs, PBBs and PBDEs in natural water samples (estuarine water and sea water) from the Bilbao estuary (Northern Spain) and comparable results were obtained with both procedures.

Polybrominated diphenyl ethers and polybrominated biphenyls in Australian sewage sludge

This paper presents a brief review of the international scientific literature of polybrominated diphenyl ethers (PBDEs) and polybrominated biphenyls (PBBs) in sewage sludge and a survey of these compounds in sewage sludge from 16 Australian wastewater treatment plants (WWTPs). The ΣPBDE mean concentration in the Australian study was 1137 μg kg −1 dry weight (d.w.) (s.d. 1116) and ranged between 5 and 4 230 μg kg −1 d.w. The urban mean of 1308 μg kg −1 (s.d. 1320) and the rural mean of 911 μg kg −1 (s.d. 831) are not statistically different and are similar to levels in European sludges. Principal components analysis was performed on the data set and revealed that 76% of the data variation could be explained by two components that corresponded to overall concentration of the pentaBDE and the decaBDE commercial formulations. An analysis of variance was performed comparing PBDEs levels at three WWTPs over the years 2005 and 2006, finding differences between treatment plants (BDE-47) but no significant difference in PBDE levels in the years 2005 and 2006. Low levels of BB-153 were detected in all samples of this survey ( n = 16); mean 0.6 μg kg −1 d.w. (s.d. 0.5). This compound has rarely been reported in any other study of sewage sludges undertaken outside Australia. This work highlights the need for a risk assessment of PBDEs in sewage sludge when used for land application, taking into account typical levels found in Australian sludges and soils.

Versatile and fast gas chromatographic determination of frequently used brominated flame retardants in styrenic polymers

Two versatile and fast methods to identify and quantify brominated flame retardants (BrFRs) in styrenic polymers were developed. Gas chromatography/mass spectrometry (GC/MS) as well as gas chromatography with electron-capture detection (GC/ECD), both following ultrasonic-supported dissolution and precipitation (USDP), were applied. The substance range includes poly-brominated biphenyls (PBBs) and diphenyl ethers (PBDEs), as well as other commonly used flame retardants (FRs), including two phosphate-based flame retardants. The methods were verified using congener standards and flame-retardant polymer samples. Good recoveries were found. Overall run time for the analysis, including sample preparation, is less than 60 min.

Mechanism and kinetics of reductive dehalogenation of PBB (polybrominated biphenyl) in the sonolytic and ketyl radical system

The kinetics and mechanism of reductive destruction of aqueous polybrominated biphenyl (PBB) were studied. Complete degradation was achieved within 30 min of ultrasound-assisted chemical process (UACP), which involved sonication, ketyl radical and its anion, and metal catalyst (ferrous ion). Reductive dehalogenation of PBB is a first-order reaction between PBB concentration and UACP reaction time. The kinetic condition of PBB degradation was optimized in terms of temperature, dosage of radical initiator, and metal catalyst. Mechanism of reductive debromination was also proposed to explain the function of ketyl and aryl radicals on the debromination of bromobiphenyl. Two kinetic models were studied to elucidate the debromination mechanism pathway. Laboratory observed data were found to fit model predicted values obtained from equilibrium and differential equations.

Comment on “The influence of age at exposure to PBBs on birth outcomes”

To the Editor: We would like to comment on the article entitled “The influence of age at exposure to PBBs on birth outcomes” (Sweeney and Symanski, 2007, doi:10.1016/j.envres.2007.03.006). We have analyzed a mostly overlapping dataset described in our recently published article, “Maternal exposure to polybrominated and polychlorinated biphenyls: Infant birth weight and gestational age” (Givens et al., 2007). In brief, our sample included 899 infant birth records from 1975–1997 from women in the Michigan Long–Term Polybrominated Biphenyl (PBB) Study who also participated in the 1997–1998 Michigan Female Health Study telephone interview. The study population in Sweeney and Symanski (2007) included a total of 1,111 infant birth records from 1975–1994 from the Michigan Long–Term PBB Study cohort and a smaller cohort, the PCB Silo Cohort. Birth weight and gestational age were analyzed as separate outcomes in mixed–effects models in both articles; however, we found results that differed from Sweeney and Symanski (2007). Our birth weight model (Givens et al., Table 2, 2007) included similar covariates to Sweeney and Symanski’s (2007) model presented in Table 4 (gestational age, maternal age at infant’s birth, PBB, PCB, parity, and infant gender) and a few additional covariates (maternal smoking status and decade of infant’s birth). In comparison to Sweeney and Symanski’s (2007) model, we did not include maternal age at enrollment, interval between blood test (taken at enrollment) and date of infant’s birth, maternal BMI at enrollment, prenatal care and paternal education. Table 2 Collinearity Diagnostics - Principal Components Analysis^ Because our published results were contrary to Sweeney and Symanski’s (2007) results, we have attempted to replicate Sweeney and Symanski’s (2007) findings by including the additional variables of interval and maternal age at enrollment. Although our sample and methodological approaches are somewhat different, we were successfully able to reproduce similar parameter estimates as those presented in Sweeney and Symanski’s (2007) Table 4 (Table 1). Specifically, we were able to reproduce the association of maternal age at enrollment ≤ 10 years with approximately a 200 g heavier birth weight. However, we would like to raise several concerns with the interpretation of this result. The overall conclusion of a “maternal age at exposure” effect does not appear to be substantiated from the data for the following reasons: 1) “maternal age at enrollment” was used as a proxy for “maternal age at exposure,” without considering the potential error introduced by this proxy, 2) a substantial proportion of the population did not have detectable serum PBB in the blood, but Sweeney and Symanski’s (2007) models did not account for this, and 3) there are methodological issues that appear to be the source of the “maternal age at exposure” effect. Table 1 Mixed Models for Infant Birth Weight

Association of Brominated Flame Retardants With Diabetes and Metabolic Syndrome in the U.S. Population, 2003–2004

OBJECTIVE—Chlorinated persistent organic pollutants (POPs), endocrine disruptors accumulated in adipose tissue, were associated with diabetes and metabolic syndrome. Brominated flame retardants (BFRs), such as polybrominated diphenyl ethers (PBDEs) or polybrominated biphenyls (PBBs), are another class of POPs for which body burden is increasing. Cross-sectional associations of serum concentrations of BFRs with diabetes and metabolic syndrome were studied.RESEARCH DESIGN AND METHODS—In the National Health and Nutrition Examination Survey 2003–2004, 1,367 adults were examined with respect to diabetes status. Five PBDEs and one PBB were selected, detectable in ≥60% of participants. For the outcome metabolic syndrome, we restricted the analysis to 637 participants with a morning fasting sample.RESULTS—Compared with subjects with serum concentrations below the limit of detection, prevalent diabetes had differing dose-response associations with serum concentrations of PBB-153 and PBDE-153. Adjusted odds ratios across quartiles of serum concentrations for PBB-153 or PBDE-153 were 1.0, 0.7, 1.4, 1.6, and 1.9 (P for trend <0.01) and 1.0, 1.6, 2.6, 2.7, and 1.8 (P for quadratic term <0.01), respectively. PBB-153 was also positively associated with the prevalence of metabolic syndrome with adjusted odds ratios of 1.0, 1.5, 3.1, 3.1, and 3.1 (P for trend<0.01). As in its association with diabetes, PBDE-153 showed an inverted U-shaped association with metabolic syndrome.CONCLUSIONS—Pending confirmation in prospective studies, lipophilic xenobiotics, including brominated POPs stored in adipose tissue, may be involved in the pathogenesis of diabetes and metabolic syndrome.

Detailed analysis of polybrominated biphenyl congeners in bird eggs from Norway

Individual eggs of six species of birds from Norway representing different food chains were analysed for residues of polybrominated biphenyls (PBBs). In all species, the residue pattern was dominated by hexaBBs. The dominating congeners were PBB 153, PBB 154, and PBB 155. Whereas PBB 153 is present in technical hexabromobiphenyl, PBB 154 and PBB 155 are formed by the reductive debromination of decabromobiphenyl. This was evidenced by the detection of several heptaBBs and octaBBs all of which are typical degradation intermediates of PBB 209. Hepta- and octaBBs were more than one order of magnitude less abundant than the hexaBBs. The second most prevailing homologue group was pentaBBs. The most relevant pentabrominated isomers were PBB 99 and PBB 101. Concentrations of the three hexaBBs--PBB 153, PBB 154, and PBB 155--amounted to 1.3-13 ng/g wet weight or 3-23% of the contamination with polybrominated diphenyl ethers.

Cryptorchidism: Main et al. Respond

ten Tusscher and Koppe point out that maternal diabetes increases the risk of malformations in newborns and suggest that we should have excluded diabetic mothers from the data set. We agree with them that maternal diabetes increases the risk of congenital malformations, although there is only limited evidence for this in the case of cryptorchidism. In our large mother–child cohort from which this data set was derived, we found a significant association between gestational diabetes and congenital cryptorchidism (Virtanen et al. 2006). We did not initially carry out an analysis corrected for diabetes because the biological samples were not selected with regard to diabetes; therefore data were potentially skewed for this outcome. For the same reason, the total number of mothers with diabetes in each country was low in this data set. We have now reanalyzed the data, omitting the mothers with diabetes (2 Danish and 4 Finnish mothers for breast milk samples, and 2 Danish and 10 Finnish mothers for placentas). In a binary logistic regression analysis including all relevant confounders (maternal age, maternal prepregnancy body mass index, gestational age, weight for gestational age, parity, and country of origin), the association between the level of the seven most prevalent polybrominated biphenyl ethers (PBDEs) in breast milk (BDEs 28, 47, 66, 99, 100, 153, and 154) and congenital cryptorchidism remained significant (p < 0.032), with a median level (2.5th–97.5th percentiles) of 3.16 ng/g fat (1.08–21.73) in controls and 4.19 ng/g fat (1.42–52.64) in cryptorchid boys. The same analysis for the five most prevalent BDEs in placenta (BDEs 47, 153, 99, 100, and 28) remained nonsignificant (p = 0.173), with 1.23 ng/g fat (0.56–5.46) in controls and 1.12 ng/g fat (0.37–4.24) in cryptorchid boys. ten Tusscher and Koppe also suggest the investigation of potential differences between mothers with and without diabetes with respect to fat content in the samples and the concentrations of PBDEs. We previously reported that the lipid content in breast milk and placenta was higher in Finnish than in Danish samples (Shen et al. 2007). Country of origin was therefore included as a covariate in a binary logistic regression. We found no significant difference between mothers with and without diabetes for fat content in breast milk or placenta (p = 0.975 and 0.107, respectively) or the sum of the most prevalent BDE congeners (p = 0.233 and 0.317, respectively). However, the number of diabetic mothers in our data set is too small to draw any firm conclusions from these results. In conclusion, the association between perinatal exposure to PBDEs and congenital cryptorchidism was significant after exclusion of diabetic mothers. Exposure to environmental chemicals is, however, one of many adverse factors that alone, or in combination with each other, may cause testicular maldescent (Main et al. 2007). These additional factors include gestational complications, lifestyle, and genetic factors (Virtanen et al. 2007).

Supercritical fluid extraction of polyhalogenated pollutants from aquaculture and marine environmental samples: A review

This article focuses on the state-of-the-art in sample preparation using supercritical fluid extraction (SFE), to monitor the content of polyhalogenated pollutants in aquaculture and marine environmental samples. Marine sediments and biological applications, including several types of samples matrices (fish, shellfish, seaweed and fish feed) and analyte groups (polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polybrominated diphenylethers (PBDEs), polychlorinated dibenzo-p-dioxin (PCDD)/Fs and organochlorinated pesticide (OCPs)) are discussed with respect to SFE use and optimisation of conditions. We also discuss the great analytical potential of SFE, the integration of the extraction and clean-up steps for rapid sample processing justifying its use for routine work. The most recent SFE applications to the determination of these pollutants in marine environmental (biota and sediment) samples, published in the last 15 years, are reviewed.

Serum Levels of Polybrominated Diphenyl Ethers (PBDEs) in Foam Recyclers and Carpet Installers Working in the United States

Increased exposure to the flame retardants known as polybrominated diphenyl ethers (PBDEs) may be expected to occur during the recycling of polyurethane foam containing these chemicals. To date, no studies in the United States have investigated occupational exposure to these flame retardants during recycling processes. The objective of the present study was to determine if individuals working in foam recycling facilities, and/or carpet installers who may install carpet padding manufactured from recycled foam, possess significantly higher PBDE serum levels relative to that of the general U.S. population. As a control group, serum was collected from four spouses and one clerical worker. In addition, levels in workers were also compared to the recently published national health and nutrition examination survey (NHANES) data set on PBDEs in the general U.S. population. Serum samples were collected in duplicate and analyzed by two different laboratories as quality control. Total PBDE levels were found to be significantly higher (p < 0.05) in the individuals recycling foam and installing carpet (n = 15) relative to the control group (n = 5). Median sigmaPBDE levels in the foam recyclers, carpet layers, and control group were 160, 178, and 19 ng/g lipid, respectively. In contrast, concentrations of a polybrominated biphenyl (BB-153) and a polychlorinated biphenyl (CB-153) were equivalent among all groups tested. The PBDE congeners BDE-47, 99, 100, and 153 contributed 90% of the sigmaPBDE concentration in serum and no differences in congener patterns were apparent among the different groups. Relative to concentrations measured in the NHANES, foam recyclers and carpet layers have body burdens that are an order of magnitude higher. These data suggest individuals recycling foam-containing products, and/ or using products manufactured from recycled foam (i.e., carpet padding), have higher body burdens of PBDEs, and thus may be at higher risk from adverse health effects associated with brominated flame retardant exposure.

Congener pattern of hexabromobiphenyls in marine biota from different proveniences

Blubber of seals, harbour porpoises and fish originating from the North Sea, the Baltic Sea, as well as coastal waters of Iceland and North America were analyzed for residues of polybrominated biphenyls. According to GC/ECNI-MS, hexabromobiphenyls (hexaBBs) dominated in the samples, followed by pentabromobiphenyls (pentaBBs) and heptabromobiphenyls (heptaBBs), whereas octabromobiphenyls (octaBBs) were only detected in selected samples and nonabromobiphenyls (nonaBBs) and PBB 209 were not found at all. Eleven peaks of hexaBBs—two peaks might have been each composed of two congeners, respectively—were detected in the different samples. The hexaBB pattern in samples of Iceland was a mixture of the pattern determined in samples from North America and continental Europe. In samples from the European continent, the major congener in technical hexabromobiphenyl, PBB 153, accounted for 11–37% of the hexaBBs. Other prominent isomers were PBB 155 (7.1–64%) and PBB 154 (11–33%), followed by PBB 133 as well as PBB 132 and/or PBB 146. Most of these PBBs were determined for the first time in marine biota and must be metabolites of higher brominated PBBs since they were not present in any technical product. PBB 153 was dominant in blubber of marine mammals from North America (92–96%). Blubber of harbour porpoises and also seal milk showed more peaks, which is indicative of a lower capability of biotransforming PBBs. It is concluded from this and other studies that PBB residues in North America are mainly originating from technical hexabromobiphenyl, while the bulk of the PBB residues in the European marine samples originated from technical octa- and decabromobiphenyl. Finally, it is evident from this study that a global ban of PBBs should not only be restricted to hexabromobiphenyls, but also needs to include higher brominated mixtures.

Brominated flame retardants in fish and shellfish – levels and contribution of fish consumption to dietary exposure of Dutch citizens to HBCD

In order to determine the contamination with brominated flame retardants (BFR) in fish regularly consumed by Dutch citizens, 44 samples of freshwater fish, marine fish, and shellfish were analyzed for polybrominated diphenyl ethers (PBDE), tetrabromobisphenol-A (TBBP-A) and its methylated derivative (me-TBBP-A), and hexabromocyclododecane (HBCD), including its alpha-, beta- and gamma-diastereomers. The highest BFR concentrations were found in pike-perch and eel from the highly industrialized and urbanized rivers Rhine and Meuse. The sum concentrations of BDE 28, 47, 99, 100, 153, 154, 183, 209, and brominated biphenyl (BB) 153 and HBCD (selection based on The European Food Safety Authority monitoring recommendation) ranged from below quantification limits to 17 ng/g wet weight (ww) in marine fish and in freshwater fish from 0.6 ng/g ww in pike-perch to 380 ng/g ww in eel. The BDE congener profile in all fish and shellfish samples is dominated by BDE 47, followed by BDE 99, except for eel in which BDE 100 is higher than BDE 99. BDE 209 was detected in two mussel samples, most likely due to BDE 209 contaminated particulate matter in their intestines. Total-HBCD (as determined by GC/electron capture negative ion (ECNI)-MS) was detected in 22 out of the 44 samples in concentrations between 0.20 ng/g in marine fish and 230 ng/g ww in eel. Three HBCD diastereomers were determined by HPLC/ESI-MS/MS. alpha-HBCD was the prevalent congener in most fish samples, followed by gamma-HBCD. beta-HBCD, TBBP-A and me-TBBP-A were only detected in a few samples and at low concentrations. A considerable difference was found between HBCD results obtained from GC/ECNI-MS and HPLC/ESI-MS/MS: the GC/ECNI-MS results were 4.4 times higher, according to regression analysis. There is hardly any data on human dietary exposure to HBCD available. We have estimated the fish-related dietary exposure of HBCD for the average Dutch population. The medium bound intake was estimated at 8.3 ng/day for a 70-kg person (0.12 ng/kg bodyweight/day). For this estimation, we relied mostly on HPLC/ESI-MS/MS data as we argue that these results are more accurate than those obtained by GC/ECNI-MS.