Determination of polybrominated diphenyl ethers in human milk samples in the Czech Republic

Persistent Organic Pollutants in Austrian Human Breast Milk Collected between 2013 and 2016

Breast milk holds an immense nutritional value as it contains health-promoting substances in a unique, optimal form. Additionally, breast milk's significance extends to health and environmental protection, as it serves as an indicator of both maternal and infant exposure. In this study, breast milk samples collected in 2013 and in 2014-2016 from mothers in Vienna (Austria) were analysed for polybrominated diphenyl ethers (PBDE) and per- and polyfluoroalkyl substances (PFAS), as well as further substances which have been listed under the Stockholm Convention on Persistent Organic Pollutants (POPs) due to their persistent, bioaccumulative and toxic properties. The total concentration of the PBDE congeners in the samples (n = 18, sampled 2013) ranged from 0.055 to 52 ng/g lipid, and from 0.002 to 2.5 ng/g breast milk. In the pooled sample, the sum of PBDEs was detected at a level of 4.4 ng/g lipid. Based on the 2014-2016 study population, certain PFAS were detected in all samples (n = 40). Exposure to the sum of four specific PFAS including perfluorooctanesulphonate (PFOS), perfluorooctanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA) and perfluoro-1-hexanesulfonate (PFHxS) ranged between 0.014 and 0.12 ng/L breast milk. In the pooled sample, PFOS and PFOA were found in concentrations of 0.025 ng/g and of 0.045 ng/g, respectively. In addition, the first generation of POPs, mainly organochlorine compounds, was measured in a pooled sample of breast milk from participants sampled in 2014-2016 as part of the WHO/UNEP breast milk monitoring program and compared to the POPs measured in pooled samples collected in 1987/1988 and 1992/1993, respectively. Therefore, this paper demonstrates the effectiveness of the Stockholm Convention on POPs by comparing the Austrian results from the WHO/UNEP global breast milk study from 1987 to 2016. However, the data also show that, despite these reductions, health-relevant levels are still being reached, particularly in terms of children's health when the presence of the new generation of POPs, such as PBDEs and PFAS, in human breast milk is taken into account.

Has Regulatory Action Reduced Human Exposure to Flame Retardants?

Flame retardant (FR) exposure has been linked to several environmental and human health effects. Because of this, the production and use of several FRs are regulated globally. We reviewed the available records of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDDs) in human breast milk from literature to evaluate the efficacy of regulation to reduce the exposure of FRs to humans. Two-hundred and seven studies were used for analyses to determine the spatial and temporal trends of FR exposure. North America consistently had the highest concentrations of PBDEs, while Asia and Oceania dominated HBCDD exposure. BDE-49 and -99 indicated decreasing temporal trends in most regions. BDE-153, with a longer half-life than the aforementioned isomers, typically exhibited a plateau in breast milk levels. No conclusive trend could be established for HBCDD, and insufficient information was available to determine a temporal trend for BDE-209. Breakpoint analyses indicated a significant decrease in BDE-47 and -99 in Europe around the time that regulation has been implemented, suggesting a positive effect of regulation on FR exposure. However, very few studies have been conducted globally (specifically in North America) after 2013, during the time when the most recent regulations have been implemented. This meta-analysis provides insight into global trends in human exposure to PBDEs and HBCDD, but the remaining uncertainty highlights the need for ongoing evaluation and monitoring, even after a compound group is regulated.

Evaluation of the Burdening on the Czech Population by Brominated Flame Retardants

The completed environmental study was concerned with assessing the exposure of the Czech population to polybrominated diphenyl ethers (PBDEs). Simultaneously, the levels of polychlorinated pollutants such as polychlorinated biphenyls (PCBs) and chlorinated diphenyl ethanes (DDTs) were also monitored. The pollutant levels were newly measured in solid fat tissue removed during plastic surgery. A total of 107 samples of fat were taken from 19–76-year-old volunteers. A total of 16 PBDE congeners were determined, of which only six occur in more than 38% of fat tissue samples. The total PBDE level attains an average value of 3.31 ng/g, which is 25% less than was measured in 2009. On the other hand, there was an increase in the levels of two PCB congeners, which was caused by an increase of the total PCB concentration from level of 625.5 ng/g, published in 2009, to the current level of 776 ng/g. The level of DDTs decreased and currently has a value of 467.4 ng/g, which is about 24% lower than in 2009. The contamination of obese middle-aged women in Czechia by more modern types of pollutants, such as PBDEs, is incomparably lower than that by PCBs and DDTs and is also decreasing in time.

Legacy and alternative halogenated flame retardants in human milk in Europe: Implications for children's health

In this study, 10 polybrominated diphenyl ethers (PBDEs) and 19 alternative halogenated flame retardants (AFRs) were determined in >450 human milk samples across three European countries, representing northern, western and eastern Europe. This study provides first insights into the occurrence of selected AFRs in mother milk samples and compares them among three European countries. Sums of median concentrations of the most frequently detected PBDEs were 2.16, 0.88 and 0.45ngg^-1 lipid weight (lw) in Norway, the Netherlands and Slovakia, respectively. The sum of the concentrations of AFRs ranged from 0.14 to 0.25ngg^-1lw in all countries, which was 2 to 15 times less compared to Σ₇PBDEs. The Penta-BDE replacement, bis(2-ethylhexyl) tetrabromophthalate, BEH-TEBP, was present at the greatest concentrations of any of the AFRs and in some samples exceeded concentrations of BDE 47 and BDE 153. Four AFRs including bromobenzenes (hexabromobenzene, pentabromobenzene, pentabromotoluene) and another Penta-BDE replacement (2-ethylhexyl-2,3,4,5-tetrabromobenzoate, EH-TBB) were detected in >42% of all human milk samples. Because of the potential developmental neurotoxicity of the halogenated flame retardants, infant dietary intakes via breastfeeding were estimated; in four cases the intakes of BDE 47 exceeded the reference dose indicating that the present concentrations may pose a risk for children.

Rapid Characterization of the Human Breast Milk Lipidome Using a Solid-Phase Microextraction and Liquid Chromatography-Mass Spectrometry-Based Approach

Human breast milk (HBM) is a biofluid consisting of various biomolecules such as proteins, lipids, carbohydrates, minerals and bioactive substances. Due to its unique and complex composition, HBM provides not only nutritional components required for the growth of the infant, but also additional protection against infections. Global insight into the composition of HBM is crucial to understanding the health benefits infants receive from breastfeeding and could be used to improve the composition of milk formula for babies that cannot be breastfed. To improve global profiling of the HBM lipidome, a new analytical approach based on solid-phase microextraction (SPME) and liquid chromatography-mass spectrometry (LC-MS) was developed. The new extraction method allows for the rapid and simple extraction of a broad range of lipids directly from HBM samples. Moreover, the optimized two-step lipid extraction protocol ensures high lipidome coverage without using toxic solvents such as chloroform. The use of liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) and an automated search of a lipid database allows comprehensive identification of the lipids contained in HBM. The demonstrated analytical approach based on SPME sample preparation and LC-Q-TOF-MS is rapid, free of toxic solvents, and suited for the qualitative analysis of the HBM lipid composition.

Trends in the application of high-resolution mass spectrometry for human biomonitoring: An analytical primer to studying the environmental chemical space of the human exposome

Global profiling of xenobiotics in human matrices in an untargeted mode is gaining attention for studying the environmental chemical space of the human exposome. Defined as the study of a comprehensive inclusion of environmental influences and associated biological responses, human exposome science is currently evolving out of the metabolomics science. In analogy to the latter, the development and applications of high resolution mass spectrometry (HRMS) has shown potential and promise to greatly expand our ability to capture the broad spectrum of environmental chemicals in exposome studies. HRMS can perform both untargeted and targeted analysis because of its capability of full- and/or tandem-mass spectrum acquisition at high mass accuracy with good sensitivity. The collected data from target, suspect and non-target screening can be used not only for the identification of environmental chemical contaminants in human matrices prospectively but also retrospectively. This review covers recent trends and advances in this field. We focus on advances and applications of HRMS in human biomonitoring studies, and data acquisition and mining. The acquired insights provide stepping stones to improve understanding of the human exposome by applying HRMS, and the challenges and prospects for future research.

Persistent Organic Pollutants and Concern Over the Link with Insulin Resistance Related Metabolic Diseases

Persistent organic pollutants (POPs) are mostly halogenated compounds tending to persist in the environment, enter into the food chain, and accumulate in fat mass of mammals due to their high lipophilicity. They include some organochlorine pesticides, polychlorinated biphenyls, brominated flame retardants and polycyclic aromatic hydrocarbons. Some of these chemicals were widely used in the past so that their residues can be detected in the human body, though their usage has been banned for years. POPs have been shown to perturb the health of biological systems in different ways evidenced by carcinogenicity and disrupting effects on endocrine, immune, and reproductive systems. There are many epidemiologic and experimental studies on the association of exposure to POPs with insulin resistance and related metabolic disorders like obesity, diabetes, and metabolic syndrome. Inflammation as a known mechanism accompanying insulin resistance has also been shown to arise in insulin target tissues exposed to POPs. This review addresses the breast milk concentration of POPs in different regions of the world, synthesizes the current information on the association of POPs with insulin resistance related metabolic disorders, and discusses the inflammation as an involved mechanism. Considering high prevalence of insulin resistance related metabolic diseases and their relation with POPs, much need is felt regarding international and regional programs to not only limit their production and usage but eliminate these persistent pollutants from the environment.

Spatial and temporal trends of the Stockholm Convention POPs in mothers' milk -- a global review

Persistent organic pollutants (POPs) have been of environmental and health concern for more than half a century and have their own intergovernmental regulation through the Stockholm Convention, from 2001. One major concern is the nursing child's exposure to POPs, a concern that has led to a very large number of scientific studies on POPs in mothers' milk. The present review is a report on the assessment on worldwide spatial distributions of POPs and of their temporal trends. The data presented herein is a compilation based on scientific publications between 1995 and 2011. It is evident that the concentrations in mothers' milk depend on the use of pesticides and industrial chemicals defined as POPs. Polychlorinated biphenyls (PCBs) and "dioxins" are higher in the more industrialized areas, Europe and Northern America, whereas pesticides are higher in Africa and Asia and polybrominated diphenyl ethers (PBDEs) are reported in higher concentrations in the USA. POPs are consequently distributed to women in all parts of the world and are thus delivered to the nursing child. The review points out several major problems in the reporting of data, which are crucial to enable high quality comparisons. Even though the data set is large, the comparability is hampered by differences in reporting. In conclusion, much more detailed instructions are needed for reporting POPs in mothers' milk. Temporal trend data for POPs in mothers' milk is scarce and is of interest when studying longer time series. The only two countries with long temporal trend studies are Japan and Sweden. In most cases, the trends show decreasing concentrations of POPs in mothers' milk. However, hexabromocyclododecane is showing increasing temporal concentration trends in both Japan and Sweden.

Negative chemical ionization gas chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry and automated accurate mass data processing for determination of pesticides in fruit and vegetables

Gas chromatography coupled to high resolution hybrid quadrupole time-of-flight mass spectrometry (GC-QTOF MS), operating in negative chemical ionization (NCI) mode and combining full scan with MSMS experiments using accurate mass analysis, has been explored for the automated determination of pesticide residues in fruit and vegetables. Seventy compounds were included in this approach where 50 % of them are not approved by the EU legislation. A global 76 % of the analytes could be identified at 1 μg kg(-1). Recovery studies were developed at three concentration levels (1, 5, and 10 μg kg(-1)). Seventy-seven percent of the detected pesticides at the lowest level yielded recoveries within the 70 %-120 % range, whereas 94 % could be quantified at 5 μg kg(-1), and the 100 % were determined at 10 μg kg(-1). Good repeatability, expressed as relative standard deviation (RSD <20 %), was obtained for all compounds. The main drawback of the method was the limited dynamic range that was observed for some analytes that can be overcome either diluting the sample or lowering the injection volume. A home-made database was developed and applied to an automatic accurate mass data processing. Measured mass accuracies of the generated ions were mainly less than 5 ppm for at least one diagnostic ion. When only one ion was obtained in the single-stage NCI-MS, a representative product ion from MSMS experiments was used as identification criterion. A total of 30 real samples were analyzed and 67 % of the samples were positive for 12 different pesticides in the range 1.0-1321.3 μg kg(-1).

The determination of perfluoroalkyl substances, brominated flame retardants and their metabolites in human breast milk and infant formula

In the present study, a novel analytical approach for the simultaneous determination of 18 perfluoroalkyl substances (PFASs) and 11 brominated flame retardants (BFRs) including their hydroxylated metabolites and brominated phenols has been developed and validated for breast milk and infant formula. The sample preparation procedure based on extraction using acetonitrile and subsequent purification by dispersive solid-phase extraction (d-SPE) employing C18 sorbent is rapid, simple and high-throughput. Ultra-high performance liquid chromatography (UHPLC) interfaced with a tandem mass spectrometry (MS/MS) was employed for the identification/quantification of these compounds. The method recoveries of target compounds for both matrices ranged from 80% to 117% with relative standard deviations lower than 28% and quantification limits in the range of 3-200 pg/mL for milk and 5-450 pg/g for infant formula. Within the pilot study, the new method was used for the analysis of PFASs and BFRs in 50 human breast milks and six infant formulas. In the breast milk samples the total contents of PFASs and BFRs were in the range of 38-279 and 45-16,200 pg/mL, respectively. The most abundant PFASs detected in all tested breast milk samples were perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS), the latter contaminant was present not only as a linear form but also as a branched isomers. The incidence of BFRs was lower, the only representatives of this group, tetrabromobiphenol A (TBBPA) and α-hexabromocyclododecane (α-HBCD), were detected in less than 30% of breast milk samples. None of the infant formulas contained BFRs, traces of either PFOS, PFOA or PFNA were found in three samples.

State of polybrominated diphenyl ethers in China: an overview

Polybrominated diphenyl ethers (PBDEs), extensively used as flame retardants, are ubiquitous environmental contaminants that are found in both abiotic and biotic environmental samples. Sufficient evidence shows that PBDEs have been rapidly accumulating in the environment of China, especially in the Southeast regions. This paper summarizes and critically reviews the published scientific data on PBDEs in China, including the levels of PBDEs in the air, soil, water, sediment, the terrestrial and marine organisms, and human samples in China. The data preliminarily reveal the state of PBDEs in China.

A national survey of polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) in Chinese mothers' milk

Seven polybrominated diphenyl ethers (PBDEs) congeners (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154 and BDE-183) and six indicator polychlorinated biphenyls (PCBs) congeners (CB-28, CB-52, CB-101, CB-138, CB-153 and CB-180) were measured in 24 pooled human milk samples comprised of 1237 individual samples from 12 provinces in China. The samples were taken to estimate the background body burden of general population and assess nursing infant exposure via human milk in China. The median concentrations of ∑(7)PBDEs and ∑(6)PCBs were 1.49 and 10.50 ng g(-1) lipid weight (lw), respectively. BDE-28, BDE-47 and BDE-153 were predominant PBDE congeners accounting for nearly 70% of ∑(7)PBDEs. As for indicator PCBs, CB-153 was the most abundant congener, followed by CB-138. In our study, there was no significantly statistical relationship between concentrations of PBDEs in milk samples and maternal age as well as dietary habits. ∑(7)PBDEs did not correlate to ∑(6)PCBs in Chinese mothers' milk. The human exposure to indicator PCBs in China was found to be significantly determined by maternal age, dietary habits and geographical factors. It is suggested that Chinese general population is probably exposed to PBDEs with multiple sources and pathways. The estimated daily intakes (EDI) of BDE-47, BDE-99 and BDE-153 for the Chinese nursing infant were much lower than corresponding threshold reference values suggested by USEPA.

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

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

Application of mass spectrometry in the analysis of polybrominated diphenyl ethers

This review summarized the applications of mass spectrometric techniques for the analysis of the important flame retardants polybrominated diphenyl ethers (PBDEs) to understand the environmental sources, fate and toxicity of PBDEs that were briefly discussed to give a general idea for the need of analytical methodologies. Specific performance of various mass spectrometers hyphenated with, for example, gas chromatograph, liquid chromatograph, and inductively coupled plasma (GC/MS, LC/MS, and ICP/MS, respectively) for the analysis of PBDEs was compared with an objective to present the information on the evolution of MS techniques for determining PBDEs in environmental and human samples. GC/electron capture negative ionization quadrupole MS (GC/NCI qMS), GC/high resolution MS (GC/HRMS) and GC ion trap MS (GC/ITMS) are most commonly used MS techniques for the determination of PBDEs. New analytical technologies such as fast tandem GC/MS and LC/MS become available to improve analyses of higher PBDEs. The development and application of the tandem MS techniques have helped to understand environmental fate and transformations of PBDEs of which abiotic and biotic degradation of decaBDE is thought to be one major source of Br(1-9)BDEs present in the environment in addition to direct loading from commercial mixtures. MS-based proteomics will offer an insight into the molecular mechanisms of toxicity and potential developmental and neurotoxicity of PBDEs.

Body burdens of polybrominated diphenyl ethers in childbearing-aged women at an intensive electronic-waste recycling site in China

BACKGROUND, AIM AND SCOPE

This study is the first to investigate PBDE body burden with regard to the concurrent analyses of multiple human matrices, namely milk, placenta, and hair, collected from a group of childbearing-aged women at an electronic waste (e-waste) recycling site to determine the partitioning of PBDEs in these different human matrices and the possible health risks imposed to infants at the e-waste recycling site.

METHODS AND METHODS

Five sets of milk, placenta, and hair samples were collected from an e-waste site (Taizhou, Zhejiang Province) and a reference site (Lin'an city, Zhejiang Province; 245 km away from Taizhou) in China. The concentrations of total PBDEs in different human tissues were analyzed according to US EPA standard methods.

RESULTS

PBDE body burdens of women from the e-waste site (milk 117 +/- 191, 8.89-457 ng/g fat, placenta 19.5 +/- 29.9, 1.28-72.1 ng/g fat, hair 110 +/- 210, 8.47-486 ng/g dry wt.) showed significantly higher levels than those from the reference site (milk 2.06 +/- 0.94, 1.0-3.56 ng/g fat, placenta 1.02 +/- 0.36, 0.59-1.42 ng/g fat, hair 3.57 +/- 2.03, 1.56-5.61 ng/g dry wt.) and were higher than those reported in other studies, due to e-waste recycling operations, especially open burning. On a dry-weight basis, the following trend was found for PBDE among the samples from Taizhou: hair>>milk>placenta. Among the donors, the body burden of an e-waste worker ranked second. Higher brominated BDEs (hepta-BDEs) contributed a significantly greater proportion to total PBDEs in hair of the Taizhou women (20%) than that in milk (2.9%) and in placenta (2.6%). The estimated intake of PBDEs of 6-month-old breastfed infants living at the e-waste site was 572 +/- 839 ng/kg body wt/day, which was 57 times higher than that of infants from the reference site (10.1 +/- 4.60 ng/kg body wt/day). Moreover, the maximum calculated value (2,240 ng/kg body wt/day) exceeded the chronic oral reference dose for penta-BDE (2,000 ng/kg/day) of US EPA.

DISCUSSION

BDE-47 was the dominant congener accounting for 20-30% in all the individual samples, while higher-brominated congeners, for example, BDE-183 and BDE-190, contributed between 2% and 20%. The presence of hepta-BDE congeners (BDE-181, BDE-190) in hair of the women in Taizhou suggest that thermal degradation of Deca-BDE from the open burning of e-waste may have been their source because these congeners are not found in either Penta-BDE or Octa-BDE technical products. Of the three types of samples analyzed, it was also suspected that hair may be more favorable to higher-brominated compounds which might explain why the hair samples contained the highest total PBDE concentrations and the highest proportion of higher-brominated BDEs (hepta-BDEs).

CONCLUSION

This study provides evidence that primitive e-waste recycling in China leads to high PBDE body burdens in local residents and can potentially threaten the health of infants.

RECOMMENDATIONS AND PERSPECTIVES

Control measures should be imposed to minimize the level of pollutants resulting from e-waste processing operations to the environment and to humans. In-depth investigations on epidemiological studies of health impacts caused by e-waste recycling operations should be conducted. It is recommended that further measurements of PBDE levels in local food (e.g., fish, shellfish, dairy products, meat, fruits, and vegetables), dust, air, water, and human specimens be collected from a larger sample size at the e-waste processing site for the determination of human exposure pathways to PBDEs.

Searching for anthropogenic contaminants in human breast adipose tissues using gas chromatography-time-of-flight mass spectrometry

The potential of gas chromatography-time-of-flight mass spectrometry (GC-TOF MS) for screening anthropogenic organic contaminants in human breast adipose tissues has been investigated. Initially a target screening was performed for a list of 125 compounds which included persistent halogen pollutants [organochlorine (OC) pesticides, polychlorinated biphenylss (PCBs), polybrominated diphenyl ethers (PBDEs)], polyaromatic hydrocarbons (PAHs), alkylphenols, and a notable number of pesticides from the different fungicide, herbicide and insecticide families. Searching for target pollutants was done by evaluating the presence of up to five representative ions for every analyte, all measured at accurate mass (20-mDa mass window). The experimental ion abundance ratios were then compared to those of reference standards for confirmation. Sample treatment consisted of an extraction with hexane and subsequent normal-phase (NP) High performance liquid chromatography (HPLC) or SPE cleanup. The fat-free LC fractions were then investigated by GC-TOF MS.Full-spectral acquisition and accurate mass data generated by GC-TOF MS also allowed the investigation of nontarget compounds using appropriate processing software to manage MS data. Identification was initially based on library fit using commercial nominal mass libraries. This was followed by comparing the experimental accurate masses of the most relevant ions with the theoretical exact masses with calculations made using the elemental composition calculator included in the software.The application of both target and nontarget approaches to around 40 real samples allowed the detection and confirmation of several target pollutants including p,p'-DDE, hexachlorobenzene (HCB), and some polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Several nontarget compounds that could be considered anthropogenic pollutants were also detected. These included 3,5-di-tert-butyl-4-hydroxy-toluene (BHT) and its metabolite 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO), dibenzylamine, N-butyl benzenesulfonamide (N-BBSA), some naphthalene-related compounds and several PCBs isomers not included in the target list. As some of the compounds detected are xenoestrogens, the methodology developed in this paper could be useful in human breast cancer research.

Brominated flame retardants and other organochlorine pollutants in human adipose tissue samples from the Czech Republic

Brominated flame retardants (BFRs) represented by polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) together with major persistent organochlorine pollutants, polychlorinated biphenyls (PCBs) and selected organochlorine pesticides (OCPs), were determined in adipose tissue samples (n=98) obtained by liposuction of Czech subjects. Compared to other organochlorine pollutants (mostly PCBs and DDTs), levels of PBDE were lower by 2 orders of magnitude ranging from 0.2 to 54.3 ng/g lipid weight. PBDE congeners No. 47, 99, 153 and 183 were the most abundant constituting up to 90% of these pollutants in adipose tissue. The PBDEs content measured in this study was comparable with data reported in similar samples collected in Spain, Sweden, Belgium and Japan, whilst slightly lower than in the United States. Regarding PCBs, the dominating congeners were No. 138, 153 and 180 representing up to 90% of indicator congeners. The levels of PCBs were similar to those found in other European countries. While no age dependency was found for PBDEs, an increase of PCB and OCP levels with age was observed. Different exposure routes of donors were documented by the absence of the relationship between PCBs and OCPs.

Exposure assessment of French women and their newborn to brominated flame retardants: determination of tri- to deca- polybromodiphenylethers (PBDE) in maternal adipose tissue, serum, breast milk and cord serum

In the frame of a French monitoring program, tri- to deca- polybromodiphenylethers (PBDE) have been measured in maternal and cord serum, adipose tissue, and breast milk samples, collected from 93 volunteer women during caesarean deliveries. The seven major tri- to heptaBDE (BDE-28, 47, 99, 100, 153, 154, and 183) were detected in adipose tissue and breast milk with cumulated median values of 2.59 and 2.51 ng g(-1) l w. Nine highly brominated octa- to decaBDE (BDE-196, 197, 201, 202, 203, 206, 207, 208 and 209) was performed in the same samples, with cumulated median values of 2.73 and 3.39 ng g(-1) l w in adipose tissue and breast milk, respectively. At this opposite, median levels of octa- to decaBDE in maternal and cord serum appeared significantly higher than the levels of tri- to heptaBDE in the same matrices, i.e. 8.85 and 12.34 versus 0.98 and 0.69 ng g(-1) l w, respectively.

Occurrence and congener specific profiles of polybrominated diphenyl ethers and their hydroxylated and methoxylated derivatives in breast milk from Catalonia

The presence of polybrominated diphenyl ethers (PBDEs) from mono to hepta brominated and 11 hydroxylated (OH-) and methoxylated (MeO-) PBDEs was examined in 37 breast milk samples collected from 11 mothers living in Barcelona. An extraction method based on accelerated solvent extraction followed by gas chromatography coupled to high resolution mass spectrometry was used to inequivocally identify all target compounds at the low pg g(-1) lw level. Data obtained were examined for absolute and relative concentrations and specific PBDE, OH- and MeO-PBDE congener patterns. Sigma PBDE concentration ranged between 1,161 and 1,372,797 pg g(-1) lw and BDEs 47, 99, 100, 153 and 183 accounted for more than 80% of the total PBDEs. All tri and tetra OH- and MeO-PBDEs compounds were detected at levels between 6 and 14,984 pg g(-1)lw. The median ratio OH/PBDE and MeO-PBDEs/PBDEs was from 2.9% to 1.6%, respectively, suggesting either that PBDE metabolism to OH- and MeO- derivatives is not an important degradation route in humans or either OH- and MeO-PBDEs are rapidly excreted. No significant correlation was observed between PBDEs and OH- and MeO-PBDE, although OH- and OMe-PBDEs co-occurred in mothers' milk (R(2)=0.5349). According to the daily intake of PBDEs and OH- and MeO-PBDEs, which was between 0.47 and 363 ng d(-1) (excluding a smoking donor), potential health risks associated with these compounds are assessed.

Levels and congener specific profiles of PBDEs in human breast milk from China: implication on exposure sources and pathways

Fourteen PBDE congeners from mono- to deca-BDE were determined in breast milk of primiparous mothers from two locations in East China, i.e. Nanjing (n=9), an urban area, and Zhoushan (n=10), a semi rural coastal area. PBDEs were detected in all the human breast milk samples of the present study, indicating that general population in these two locations are widely exposed to these pollutants. Relatively higher concentrations of PBDEs were found in the milk of mothers from Nanjing than Zhoushan, suggesting the existence of significant sources of PBDEs in urban areas. PBDE levels in the present study were similar to those in European countries, but one or two orders of magnitude lower than in North America. Except for BDE-3, all congeners from di- to deca-BDE were detected in the samples of the present study. BDE-209, a congener considered to have less bioavailability, was detected in about 50% of the samples at concentrations higher than that of other congeners. Other higher brominated congeners, such as BDE-153, -197 and -207, were also prominent in the present study, which is different from the pattern generally observed in previous studies on human milk as well as biota samples. These results may indicate that the inhabitants of Nanjing and Zhoushan are exposed to location specific sources of PBDEs.

Exposure assessment of French women and their newborns to tetrabromobisphenol-A: occurrence measurements in maternal adipose tissue, serum, breast milk and cord serum

A French monitoring study was initiated to evaluate the exposure of fetus and newborn to brominated flame retardants (BFR). A previously developed multi-residue analytical method was used for measuring the main classes of BFR (tetrabromobisphenol-A, and tri- to decabomodiphenyl ethers) in various human biological matrices. Analyzed samples (maternal and cord serum, adipose tissue and breast milk) were collected from 93 volunteer women during caesarean deliveries. TBBPA was detected in 44% of the analyzed breast milk samples, at levels varying from 0.06 to 37.34 ng g(-1) lipid weight, but was not detected in adipose tissue. This compound was also detected in 30% of the analyzed serum samples, with similar average values in maternal and cord serum (154 pg g(-1) fresh weight versus 199 pg g(-1) fresh weight, respectively). The interpretation of the collected data permitted the demonstration of (1) a significant exposure to TBBPA both for mothers and fetuses and (2) a possible risk of overexposure of newborns through breastfeeding.

Validation of a pressurized solvent extraction and GC-NCI-MS method for the low level determination of 40 polybrominated diphenyl ethers in mothers' milk

This study reports an efficient method for the determination of 40 PBDEs from mono- to hepta-brominated in human milk. Pressurized liquid extraction (PLE) was optimized to recover PBDEs in a quantitative way using 1g of freeze dried milk. Due to the great amount of coextracted compounds, the clean-up step was optimized using alumina SPE disposable cartridges of 2 and 5 g. Whereas 2g alumina SPE failed in providing good extraction yields, all PBDEs were satisfactorily recovered using 5 g alumina SPE cartridges. Detection was performed with gas chromatography coupled to mass spectrometry with negative chemical ionization and method detection limits ranged from 0.01 to 0.05 microg kg(-1) wet weight (ww) with a good intra and inter-day variation (coefficient of variation lower than 13.4%). This method was validated by participating in an interlaboratory exercise from Quasimeme (United Kingdom), where a standard solution containing seven congeners and a certified unspiked mothers' milk were analyzed. In the standard mixture, levels between 96.915 and 570.172 microg l(-1) were quantified, whereas in certified mothers' milk, BDEs 47, 99, 100 and 154 were detected at levels from 0.010 and 0.061 microg kg(-1) ww, with an error <30%. The applicability of the method was tested experimentally in five mothers' milk samples, where only BDE 47 was detected at a maximum concentration of 10.45 microg kg(-1) lipid weight (lw). PLE succeeded in extracting all PBDEs from the sample with good reproducibility although the clean-up step had to be severely performed to eliminate sample interferences such as milk lipids and proteins.

Geographical distribution and accumulation features of PBDEs in human breast milk from Indonesia

The present study reports concentrations of polybrominated diphenyl ethers (PBDEs) and organochlorines (OCs) in human breast milk from Indonesia covering urban, suburban and rural areas. PBDEs were detected in all the samples of the present study with total concentrations ranging from 0.49 to 13 ng/g lipid wt. Geographical distribution showed that concentrations of PBDEs were relatively uniform (p>0.05) and the levels were in the same order as those in Japan and some European countries, but were one or two order lower than North America. When compared to OCs, the level of total PBDEs was lower. The congener pattern was in accordance with other studies on human matrices, in which BDE-47 was the most abundant congener. Variations of PBDE congeners in human breast milk were further discussed to elucidate the potential exposure source(s) and pathways.

Brominated flame retardants in the environment of Asia-Pacific: an overview of spatial and temporal trends

In this paper, we summarize spatial and temporal trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in coastal and marine biota, and further assess human exposure to these brominated flame retardants (BFRs) in Asia-Pacific. The review is based mainly on the studies that were conducted in our laboratory and utilized samples archived in the environmental specimen bank (es-BANK) of Ehime University, Japan. The studies suggest that the target BFRs are ubiquitous in the environment of Asia-Pacific. Examination of spatial trends reveals that concentrations of these contaminants are relatively high in samples from Korea, South China and Japan. In general, the magnitude of environmental contamination by PBDEs in Asia-Pacific, as well as human exposure to these contaminants, seem to be comparable to or slightly higher than in Europe, but lower than in North America. Evaluation of temporal trends in concentrations of BFRs in marine mammals from the coastal waters of Japan and China showed drastic increase during the last 30 years. These changes in BFR levels in samples from Japan were in line with trends in production/use of the commercial formulations. Since the withdrawal of some PBDE products from the Japanese market in the 1990s, concentrations of HBCDs appear to exceed those of PBDEs, reflecting increasing usage of HBCDs over PBDEs. The increasing environmental contamination by BFRs in Chinese coastal waters indicates that contamination by BFRs has already become evident, even in developing countries. In view of the rising environmental levels and the high consumption volume of BFRs in Asia, further efforts should be made to monitor environmental contamination by these chemicals in order to identify sources and reduce emissions.

Distribution of polybrominated diphenyl ethers in human umbilical cord serum, paternal serum, maternal serum, placentas, and breast milk from Madrid population, Spain

Median concentration of total PBDEs in maternal serum, paternal serum, umbilical cord serum, and breast milk samples were 12, 12, 17, and 6.1 ng/g lipid weight (lw) in Vallecas and 9.7, 12, 15, and 5.5 ng/g lw in Getafe. The median value found in placentas was 1.9 ng/g lw (in Vallecas). BDE 47 was the predominant congener in serum samples (maternal, paternal, and umbilical cord), while BDE 209 was predominant in placenta and breast milk samples. BDEs 196 and 197 were detected in most of the placenta and breast milk samples. The results show that PBDEs, like other POPs, can cross the placenta barrier, although the speed of the process seems to differ for each PBDE congeners. The total PBDE concentrations found in this study are consistent with research reported elsewhere. They are in the same range as those recently reported by other European and Asian studies and lower than those conducted in the U.S.A. No significant differences were found (p > 0.05) between regions, sexes, and ages, while statistically significant differences (p < 0.05) were found between maternal serum, umbilical cord serum, and breast milk samples. The presence of PBDEs in cord blood and placenta samples indicates that there is prenatal exposure of PBDEs, which could continue after birth via breast milk.

Methodical approach for the use of GC-TOF MS for screening and confirmation of organic pollutants in environmental water

The potential of gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF MS) for the screening of organic pollutants in water was explored. After a conventional SPE step with C(18) cartridges, the comparison of spectra with available libraries together with an evaluation of the mass accuracy was the first approach used for the screening and confirmation of target analytes. However, at low analyte concentrations (i.e. below 0.1 microg/l), this procedure was not feasible and the use of the application manager TargetLynx was evaluated. This application allows the selection of up to five representative ions per analyte, measured with high mass accuracy, and their intensity ratio evaluation. Ion selection, extraction mass window and concentration levels were found to be the critical parameters. The reference compound used as 'lock mass' was also found to affect to the quality of information obtained in some particular cases. Full spectral acquisition data generated by the TOF MS analyzer allowed investigation of the presence of several analytes in samples in a post-target style, without the need of reanalyze the water samples.Finally, a methodical approach was established for the reliable screening and confirmation of organic pollutants (PAHs, pesticides, octyl/nonyl phenols) in real-world samples, which led to satisfactory results of approximately 0.1 microg/l.

Polybrominated diphenyl ethers and organochlorine pesticides in human breast milk from Massachusetts, USA

Concentrations of polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides (OCPs; DDTs, HCHs, CHLs, and HCB) were measured in human breast milk samples collected across Massachusetts, USA, in 2004. Seventeen PBDE congeners were found in the samples, ranging in concentration from 0.06 to 1910 ng g(-1) lipid wt. BDE-47 (2,2',4,4'-tetraBDE), BDE-99 (2,2',4,4',5-pentaBDE), and BDE-100 (2,2',4,4',6-pentaBDE) were the major congeners detected in breast milk samples. Overall mean (+/-SD) concentrations of DDTs, HCHs, CHLs, and HCB were 64.5 +/- 75, 18.9 +/- 19, 32.4 +/- 36, and 2.3 +/- 2.2 ng g(-1) lipid wt, respectively. Concentrations of PBDEs were strongly correlated with concentrations of OCPs in the samples. Based on the concentrations of organohalogens and the intake rates of breast milk by infants in the United States, daily ingestion rates of contaminants were calculated. The median ingestion rates for PBDEs, HCHs, DDTs, CHLs, and HCB were 4.0, 212, 141, 44, and 5.79 ng kg(-1) body wt day(-1), respectively. The estimated daily intake of organohalogens by infants was compared with threshold reference values suggested by the United States Environmental Protection Agency (USEPA) and the Agency for Toxic Substances and Disease Registry (ATSDR), for calculation of hazard quotients (HQs). HQs for individual organohalogens and the sum of HQ for all organohalogens were calculated as HQ indices (HQI). The results suggest that one or more of the contaminants analyzed in this study exceeded the threshold reference values in at least 26% of the breast milk samples.

Distribution of polychlorinated biphenyls, organochlorine pesticides and polybrominated diphenyl ethers in human umbilical cord serum, maternal serum and milk from Wielkopolska region, Poland

The levels of organochlorinated pesticides (OCPs): p,p'-DDT and its metabolites, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes and their metabolites, and 18 polychlorinated biphenyl (PCB) congeners were measured in maternal serum, umbilical cord serum and human milk collected from 22 mothers living in the Wielkopolska region, Poland. Additionally, 11 polybrominated diphenyl ether (PBDE) congeners were measured in the human milk samples. p,p'-DDT and its major metabolite, p,p'-DDE, together with HCB, were found in all milk and serum samples. Median concentrations of p,p'-DDE in maternal serum, umbilical cord serum and milk were 343, 329 and 634ng/g lipid weight (lw). PCB congeners 138, 153 and 180 were the major congeners measured in all serum samples, while CB 170 was detected in 74% and 100% of umbilical cord and maternal serum, respectively. Except for CBs 74, 101 and 105, which had a detection frequency of 77%, 23% and 82%, respectively, all investigated PCB congeners were measured in all human milk samples. The median concentrations of sum PCBs in maternal serum, umbilical cord serum and milk were 79, 60 and 133 ng/g lw, respectively. A good correlation (Spearman R(S)>0.75, p<0.001) was found for major PCBs, p,p'-DDT and p,p'-DDE, between maternal and umbilical cord serum, while the correlation was weaker between milk and serum. The median of sum PBDEs in human milk was 2.0 ng/g lw (range 0.8 to 8.4), with BDE 47 being always the most abundant PBDE congener and, together with BDE 153, being present in all samples. In general, results found in the investigated group are at the low end of the concentration range measured in Europe.

Polybrominated diphenyl ethers (PBDEs) in mussels from selected French coastal sites: 1981-2003

The present study focused on the retrospective analysis of PBDEs in archived blue mussel (Mytilus edulis or Mytilus galloprovincialis) samples collected over the past 22 years (1981-2003) from coastal areas of France. We have found that PBDE levels in mussels from the English Channel increased markedly from 1981 to 1991-1995, doubling approximately every 5-6 years followed by a levelling off and a possible beginning of a decrease. The rate of the decline of hexa- and hepta-BDE congeners was more rapid than the decline of tetra- and penta-BDEs in these mussel samples. The difference in the course of time of lower and higher brominated PBDE concentrations suggests that the congener profile in the mussel samples changes over time. The increase in PBDE concentrations in the mussel samples contrasts with a concomitant constant decrease of chlorobiphenyls (CBs) in the same set of samples. However, pulse inputs of both groups of organohalogen compounds were determined for the mussel samples collected at the mouth of the Seine estuary and were probably related to riverine inundations and a flushing out of the deposited sediments from the internal estuary into the bay of the River Seine, as well as considerable dredging activities taking place during same years. In France, the highest PBDE concentrations were determined in the mussels from the English Channel, more precisely in the bay of the Seine, and the regional differences in PBDE levels were mainly connected to the difference in anthropogenic urban and industrial environmental pressures. Published data comparing PBDE levels in mussels have shown significant differences in concentrations between North/South America and Europe. This observation further confirms that the PBDE levels in the North American environment are higher than in Europe. However, the data used for this comparison of mussel contamination by PBDEs is still relatively sparse.

Suitability of tandem-in-time mass spectrometry for polybrominated diphenylether measurement in fish and shellfish samples: Comparison with high resolution mass spectrometry

The first part of the present study focused on the development of an alternative automated sample preparation method for the measurement of selected polybrominated diphenyl ethers (PBDEs) in fish and shellfish. A previously developed automated method has been further optimized and simplified to decrease blank levels and cost. Sorbent and solvent quantities have been significantly reduced without altering extract quality. The second part of the study consisted of comparing tandem-in-time quadrupole ion storage mass spectrometry (QISTMS/MS) to high resolution mass spectrometry (HRMS) for the isotope dilution (ID) measurement step after gas chromatography (GC) separation. Both mass spectrometric methods performed similarly in terms of accuracy but better precision was observed for HRMS. Although better sensitivity can be attained with the high resolution sector instrument, method limits of quantification (mLOQs) were very similar for both approaches as they were dependent on the procedural blanks levels. The mLOQ values ranged between 0.04 and 3.56 ng/g fat, depending on the congener. They allowed the unambiguous identification and quantification of all target analytes, except for BDE-183, in most considered fish extracts. An analytical procedure based on rapid automated sample preparation and QISTMS/MS appeared to be suitable for the measurement of PBDEs in fish and shellfish speciment under quality assurance/quality control (QA/QC) criteria.

Occurrence of polychlorinated biphenyls and polybrominated diphenyl ethers in belgian human adipose tissue samples

Levels of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in 53 human adipose tissue samples. The samples consisted of adipose tissue from 31 men and 22 women having a mean age of 53 years. No information about diet or occupational exposure was collected. Cleanup was performed using a glass column containing acidified silica, deactivated alumina, and anhydrous sodium sulphate. Subsequently, samples were analyzed by high-resolution gas chromatography/tandem mass spectrometry. PBDE concentrations (sum of BDEs 28, 47, 99, 100, 154, 153, and 183) ranged between 1.23 and 57.2 ng g(-1) lipid weight and were comparable with levels in samples from other European countries. The sum of seven International Council for the Exploration of the Sea (ICES) indicator PCB congeners (PCBs 28, 52, 101, 118, 138, 153, and 180) ranged from 126 to 2090 ng g(-1) lipid weight. No age dependency was found for PBDEs (Pearson correlation -0.023, p = 0.873), whereas PCBs showed higher correlation coefficients with age (Pearson correlation 0.613, p < 0.0005). There was no relationship between PBDE and PCB levels (Pearson correlation -0.010, p = 0.943).

Study of polybrominated diphenyl ethers using both positive and negative atmospheric pressure photoionization and tandem mass spectrometry

Atmospheric pressure photoionization (APPI) was assessed for the mass spectrometric analysis of polybromodiphenyl ethers (PBDEs) on the basis of a set of 17 standard compounds. Positive and negative ionization modes were both investigated. M(+.) ions were formed under positive ion conditions whereas the negative ion mode yielded [M-Br+O](-) ions. The behavior of these APPI-produced ions towards collisional activation was studied using an ion trap mass spectrometer. In positive ion mode, the loss of Br(2) was one of the major fragmentation pathways, and was favored for ortho-substituted PBDEs. Conversely, the loss of COBr(.) occurred only for non-ortho-substituted congeners. The collisional excitation of [M-Br+O](-) ions in the ion trap also led to the loss of Br(2), to the elimination of HBr, and to the formation of product ions by cleavage of the ether bond. The formation of para-quinone radical anions was observed for PBDEs ranging from penta- to hepta-congeners, whereas brominated aromatic carbanions were formed preferentially for the most brominated PBDEs studied in this work (hepta- or deca-BDEs). M(+.) ions did not undergo this fragmentation process.