Polybrominated Diphenyl Ethers In Water Research Articles

Occurrence, source identification and risk assessment of polybrominated diphenyl ethers in water and sediments of Osun River, Nigeria

BackgroundIn the present study, the concentrations of polybrominated diphenyl ethers (PBDEs) in water and sediments of Osun River, Nigeria were determined.MethodsThe obtained water samples were subjected to liquid-liquid extraction while the sediment samples were subjected to extraction using n-hexane and acetone. The extracts were quantified using a Gas Chromatography-Mass Spectrometer to assess their distribution, source identification, and ecological risk assessments.ResultsThe results of the study indicated that BDE-99, BDE-183, and BDE-209 were not detected in the water samples while BDE-28 had the most significant mean contribution (0.057 mg/L w.w) to the total PBDEs in the water samples. The sediment samples were dominated by enhanced concentrations of BDE-100 congener (mean concentration 0.184 mg/kg d.w). The compositional profiles of the PBDE congeners indicated the abundance of higher BDEs in the sediment samples compared to the water samples, a phenomenon attributed to the lower reduction rate and lower water solubility of the higher BDEs. Source identification indicated that commercial deca-BDE mixtures might represent the major source of PBDEs in the studied river. Risk assessment of PBDEs in water samples showed that the mean concentrations of tri-BDE, tetra-BDE, penta-BDE, and hexa-BDE exceeded the acceptable limits, suggesting adverse health risks to the public. Ecological risk assessment of PBDEs in sediment samples showed medium ecological risk by hexa-BDE (0.1 ≤ RQ ≤ 1) and high ecological risks due to tri-, tetra-, penta-, and deca-BDEs (RQ > 1).ConclusionThe study concludes that efficient and cost-effective remediation strategies should be developed and employed in the abatement of these persistent organic pollutants from the environment.

Kelp forest food webs as hot spots for the accumulation of microplastic and polybrominated diphenyl ether pollutants

Kelp forests (KFs) are one of the most significant marine ecosystems in the planet. They serve as a refuge for a wide variety of marine species of ecological and economic importance. Additionally, they aid with carbon sequestration, safeguard the coastline, and maintain water quality. Microplastic (MP) and polybrominated diphenyl ethers (PBDEs) concentrations were analyzed across trophic levels in KFs around Todos Santos Bay. Spatial variation patterns were compared at three sites in 2021 and temporal change at Todos Santos Island (TSI) in 2021 and 2022. We analyzed these MPs and PBDEs in water, primary producers (Macrocystis pyrifera), grazers (Strongylocentrotus purpuratus), predators (Semicossyphus pulcher), and kelp detritus. MPs were identified in all samples (11 synthetic and 1 semisynthetic polymer) and confirmed using Fourier-transform infrared microspectroscopy–attenuated total reflectance (μ-FTIR-ATR). The most abundant type of MP is polyester fibers. Statistically significant variations in MP concentration were found only in kelps, with the greatest average concentrations in medium-depth kelps from TSI in 2022 (0.73 ± 0.58 MP g−1 ww) and in the kelp detritus from TSI in 2021 (0.96 ± 0.64 MP g−1 ww). Similarly, PBDEs were found in all samples, with the largest concentration found in sea urchins from Punta San Miguel (0.93 ± 0.24 ng g−1 ww). The similarity of the polymers can indicate a trophic transfer of MPs. This study shows the extensive presence of MP and PBDE subtropical trophic web of a KF, but correlating these compounds in environmental samples is highly complex, influenced by numerous factors that could affect their presence and behavior. However, this suggests that there is a potential risk to the systems and the services that KFs offer.

Polybrominated diphenyl ethers in water, suspended particulate matter, and sediment of reservoirs and their tributaries in Shenzhen, a mega city in South China.

Urban reservoirs serve many purposes including recreation and drinking water, and larger bodies of water can alter the surrounding air temperatures, making urban areas cooler in summer and warmer in winter. However, reservoirs may also be sinks for contaminants. One such group of contaminants, the polybrominated diphenyl ethers (PBDEs), are persistent organic pollutants known to accumulate in sediments and suspended particulate matter (SPM). Few studies have been conducted on PBDEs in water, SPM, and sediment from reservoirs of Shenzhen which is a mega city in South China. To this end, 12 PBDEs were measured in water, SPM, and sediment samples during the dry season (DS) and wet season (WS), to explain the spatiotemporal distribution, congener profiles, sources, and risks of pollutants in four reservoirs (A-D) and their tributaries in the study region. The concentration of ∑12PBDEs during the DS was found to be significantly higher than that during the WS. Source apportionment suggested that commercial penta-, octa-, and deca-BDEs are the major components of PBDEs, resulting mainly from atmospheric deposition, wastewater discharge, and external water-diversion projects. Further, attention should be paid to electronic equipment manufacturing factories in the study area. Risk assessment indicated risk of PBDEs (especially BDE-209) in sediment and SPM to be of concern. This study provides important data support for the control of PBDEs in natural drinking water sources.

Rapid screening of polybrominated diphenyl ethers in water by solid-phase microextraction coupled with ultrahigh-resolution mass spectrometry.

Polybrominated diphenyl ethers (PBDEs) are considered emerging organic contaminants that attract more attention in the environment. Herein, online coupling of solid-phase microextraction and ultrahigh-resolution mass spectrometry was developed for rapid screening of eight PBDEs in water samples. This procedure was completed in 22min, about 6 times faster than the routine workflow such as solid-phase extraction coupled with gas chromatography-mass spectrometry. Thermal desorption and solvent-assisted atmospheric pressure chemical ionization were developed for the effective coupling of solid-phase microextraction (SPME) with ultrahigh-resolution mass spectrometry (UHRMS), which contributed to the signal enhancement and made the methodology feasible for environmental screening. The limits of detection and quantification were 0.01-0.50ng/mL and 0.05-4.00ng/mL, respectively. The recoveries were 57.2-75.2% for quality control samples at spiking levels of 0.8-10ng/mL (4-50ng/mL for BDE209), with relative standard deviation less than 19.0%. Twelve water samples from different river sites near industrial areas were screened using the developed method. The results showed that BDE-209 was the dominant PBDE (1.02-1.28ng/mL in positive samples), but its amount was lower than the human health ambient water quality criteria. Consequently, the developed method provides a rapid and reliable way of evaluating contamination status and risks of PBDEs in aqueous environment.

Study of the Photodegradation of PBDEs in Water by UV-LED Technology.

Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants that can arrive to water bodies from their use as flame retardants in a wide range of applications, such as electric and electronic devices or textiles. In this study, the photodegradation of PBDEs in water samples when applying UV-LED radiation was studied. Irradiation was applied at three different wavelengths (255 nm, 265 nm and 285 nm) and different exposure times. The best degradation conditions for spiked purified water samples were at 285 nm and 240 min, resulting in degradations between 67% and 86%. The optimized methodology was applied to real water samples from different sources: river, marine, wastewater (effluent and influent of treatment plants) and greywater samples. Real water samples were spiked and exposed to 4 hours of irradiation at 285 nm. Successful photodegradation of PBDEs ranging from 51% to 97% was achieved for all PBDE congeners in the different water samples with the exception of the marine one, in which only a 31% of degradation was achieved.

Polybrominated diphenyl ethers (PBDEs) in the Danjiangkou Reservoir, China: identification of priority PBDE congeners.

Although the production of polybrominated diphenyl ethers (PBDEs) has been phased out over the past decade worldwide, they are still potentially hazardous to the environment due to their persistence and toxicity. This study investigated the levels of 55 PBDEs in water and sediments from the Danjiangkou Reservoir, China. The levels of PBDEs were in the range of not detected (ND)-286.67ng/L in water and ND-236.04ng/g in sediments. BDE209 was the predominant PBDE congener and constituted 15-50% and 44-68% of the total PBDEs in water and sediments, respectively. Commercial pentaBDE products (70-5DE, DE-71) were the dominant source of tetraBDE, pentaBDE, and hexaBDE, while commercial octaBDE (79-8DE) and decaBDE (102E and 82-0DE) products were the main sources of nonaBDE and decaBDE in water. PBDEs in sediments mainly stemmed from commercial decaBDE products and combustion sources. BDE-209 posed high ecological risks to aquatic organisms and dominated the total ecological risks of PBDEs. No cancer risks and non-cancer risks were observed for PBDEs. A ranking method based on four criteria, i.e., detection frequency, concentration, ecological risk, and health risks, was proposed, and 17 PBDEs were identified as high priority PBDEs for future monitoring and management in the Danjiangkou Reservoir.

Persistent Halogenated Organic Pollutants in Surface Water in a Megacity: Distribution Characteristics and Ecological Risks in Wuhan, China.

Surface water pollution in megacities is strongly linked to human and environmental health, and surface water quality has deteriorated sharply recently because of increasing persistent halogenated organic pollutant (HOP) concentrations. In the present study, we collected 112 water samples from 14 lakes and 11 drinking water sources in Wuhan, China, and analyzed them for two typical groups of HOPs: polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). The mean values of the ΣPCB concentrations were 4.34 and 10.05ng L-1 in winter and summer, respectively. For ΣPBDE concentrations, the mean values were 0.88 and 1.53ng L-1 in winter and summer, respectively. The PCB and PBDE concentrations at most sites in summer were significantly higher than those in winter, probably because of heavy stormwater runoff in summer. The degree of urbanization predicted from the population density was positively correlated with ΣPCB concentrations in the drinking water sources in summer. PBDE and PCB composition analysis suggested the major sources were penta-BDE and Aroclor mixtures. Risk assessments showed the PBDEs in water from the Zhuankou site exceeded the threshold set by the European Union, which could result in adverse effects on aquatic organisms. Negligible noncarcinogenic risks were found for PCBs and PBDEs in the surface water with regard to drinking and bathing. However, the carcinogenic risks of PCBs for bathing in surface water were higher than the safe level of 1.00 × 10-6, implying that the surface water in Wuhan is not safe for bathing.

Sublethal or not? Responses of multiple biomarkers in Daphnia magna to single and joint effects of BDE-47 and BDE-209

Polybrominated diphenyl ethers (PBDEs) are extremely incessant anthropogenic contaminants found in the environment, with dreadful risk to aquatic ecosystems. However, there is a limited amount of data concerning their impacts on freshwater organisms. 2,2′,3,3′,4,4′,5,5′,6,6′-decabromodiphenyl ether (BDE-209) and 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) are significant components of total PBDEs in water. The sublethal effects of BDE-47, BDE-209 and their binary mixtures on the aquatic organism Daphnia magna were investigated in acute and chronic exposure experiments. Immobilization and heartbeat were studied in daphnids after 48 h of exposure. Mortality rate, breed number, Cholinesterase (ChE), Glutathione S-transferases (GST) and Catalase (CAT) activities were evaluated after 21 days of exposure. The results showed that at 100 and 200 μg/L concentration of BDE-47, immobilization rate of daphnids were inhibited by 44.0 ± 16.7% and 88.0 ± 10.9%, respectively. The binary mixture of BDE-47 and BDE-209 had uncongenial effects on immobilization of D. magna under acute toxicity test. BDE-209 significantly increased the heartbeat rate of daphnids, which increased even further when combined with BDE-47. After 21 days of exposure, daphnids exposed to single BDE-47 were physiologically altered. The combination of BDE-47 with BDE-209 significantly decreased the mortality rate of daphnids. Irrespective of the concentration, higher numbers of offsprings were produced in the mixtures compared to BDE-47 treatment alone. ChE activities significantly (p < 0.05) decreased at concentrations of 2 and 4 μg/L in single BDE-47 treatment, while GST activity significantly (p < 0.05) decreased at 0.5 μg/L. CAT activities significantly increased with BDE-47 treatments in all the tested concentrations (p < 0.05). The mixtures significantly affect ChE (p < 0.05), GST (p < 0.05) and CAT activities (p < 0.05). The results illustrated that the toxicity of the mixture of PBDE congeners exposed to aquatic organisms may have antagonistic effects. The 21 days chronic test in this study suggests that acute toxicity tests, i.e. 48-h tests, using Daphnia may lead to underestimation of risks associated with PBDEs, especially, BDE-209. Hence, there is a necessity to re-examine PBDE congeners’ environmental risk in aquatic organisms.

Levels and distribution of polybrominated diphenyl ethers in Three Gorges Reservoir, China

Abstract Polybrominated diphenyl ethers (PBDEs) were investigated in water, sediments, suspended sediments and biofilms in Three Gorges Reservoir (TGR), China. Results showed that dissolved bioavailable PBDEs in water of TGR collected with semipermeable membrane device (SPMD)-based virtual organisms (VOs) were very low in the range of n.d. to 811 pg/g lipid and the detected compounds were mainly low molecular BDEs such as BDE-15, 17, 28, 47, 49, 66, 99 and 100. The PBDE levels in the sediment core collected near the dam were also very low in the range of 84–300 pg/g dw and the detected compounds were mainly large molecular BDEs such as BDE-196, 197, 206, 207 and 208. In suspended sediments and biofilms, the levels of PBDEs ranged from 298 to 52,843 pg/g dw and the detected compounds were also mainly large molecular BDEs such as BDE- 196, 197, 201, 203, 206, 207, 208 and 209. The dominant compound was BDE-209 which accounted for more than 90% of the total BDEs. Therefore, large molecular BDEs tended to be attached on fine particles. The vertical profile of BDEs on suspended sediments (SS) showed that SSs in the middle depth of water contained high level of BDE-209. The phenomenon indicated that most of BDE-209 did not settle into the sediment in front of the dam, instead transported further to downstream.

Micro-solid phase extraction followed by thermal extraction coupled with gas chromatography-mass selective detector for the determination of polybrominated diphenyl ethers in water

A method of analyzing environmental contaminants in water based on micro-solid phase extraction (μ-SPE) followed by thermal extraction (TE) and a cold-trapping step, coupled with gas chromatography-mass selective detection (GC–MSD) was developed and validated. μ-SPE–TE– GC–MSD was employed in the determination of five polybrominated diphenyl ethers. The μ-SPE sorbent was chitosan-graphene oxide (CS-GO) composite, which was prepared by mixing CS and GO by means of ultrasonication. The CS in the composite was cross-linked with glutaraldehyde. After μ-SPE, the analytes in the extract were extracted thermally in a thermal desorption unit tube combined with a cooled injection system, coupled to GC–MSD. The extraction conditions were optimized for the detection of the target compounds in water. This method provided linearity ranges of between 0.1 and 20μgL−1 (depending on the analytes), with coefficients of determination, r2, ≥0.9982. The calculated relative recoveries were between 71.52 and 96.15% whereas precision (based on % relative standard deviations) was between 3.54 and 11.36%. The method showed limit of detection and limit of quantification ranges of between 0.007 and 0.016μgL−1, and between 0.023 and 0.054μgL−1, for the two groups of analytes, respectively. The method was applied to the determination of the target analytes in water.

A novel three-stage hybrid nano bimetallic reduction/oxidation/biodegradation treatment for remediation of 2,2′4,4′-tetrabromodiphenyl ether

Due to the high toxicity, bioaccumulation and persistence of polybrominated diphenyl ethers (PBDEs), their mineralization is becoming a wide-spread environmental concern. In this study, a novel three-stage hybrid nano bimetallic reduction/oxidation/biodegradation treatment, consisting of nZVI/Pd reduction, advanced oxidation induced by the nZVI/Pd-O2 system and biodegradation by Pseudomonas putida, was employed to mineralize BDE47. Considering its high recalcitrance, BDE47 (5mg/L) was difficult to decompose with advanced oxidation and biodegradation. Nevertheless, after overall debromination by nZVI/Pd bimetallic particles, the final products (diphenyl ether) could be rapidly oxidized by the subsequent advanced oxidation in 90min, generating plentiful phenolic compounds such as phenol, catechol and p-hydroquinone. Subsequently, the phenolic compounds could be removed by the P. putida strain via the tricarboxylic acid cycle (TCA). To verify the degradation mechanism, UPLC and GC/MS were employed to detect the major intermediates during the entire process. Furthermore, XRD and XPS analyses indicated the formation of lepidocrocite and magnetite on the surface of nZVI/Pd during the oxidation process. Importantly, this hybrid process could completely mineralize BDE47 in a short time and avoid the generation of toxic byproducts, in addition to the extra oxidant and the secondary pollution of Fe ions, which was significant for the remediation of PBDEs in water.

Determination of polybrominated diphenyl ethers in water at ng/L level by a simple DLLME–GC–(EI) MS method

Dispersive liquid–liquid microextraction (DLLME) is an extraction procedure gaining popularity in the recent years due to the easiness of operation, high enrichment factors, low cost and low consumption of organic solvents. This extraction method, prior to gas chromatography with mass spectrometry detection (GC–MS), was optimized for the determination of polybrominated diphenyl ethers (PBDEs) in aqueous samples. These were extracted with chlorobenzene (extraction solvent) and acetonitrile (dispersive solvent), allowing an enrichment factor of about 470 for BDE-100. The calibration curve for BDE-100 was linear in the range of 0.005–10 μg/L, with an average reproducibility of 12% (RSD, %). The LOD, calculated by the signal-tonoise ratio, was 0.5 ng/L for BDE-100 and the recovery ranged from 91–107% for all spiked samples. Relative expanded uncertainty was concentration-dependent, reaching high values near the limit of quantification and decreasing until 14% for concentrations higher than 1 μg/L of BDE-100. The dispersive liquid–liquid microextraction combined with gas chromatography with mass spectrometry detection (DLLME–GC–MS) method could be successfully applied to the determination of other PBDEs in water samples.

Determination of nine hydroxylated polybrominated diphenyl ethers in water by precolumn derivatization-gas chromatography–mass spectrometry

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs), acting as emerging endocrine disruptors, have aroused more and more concern recently. Produced from natural source or metabolism of PBDEs, OH-PBDEs are more toxic than their parent compounds. However, few analytical methods are available for sensitive determination of these compounds especially in water. In this study, a method of determination of nine OH-PBDEs in lake, reservoir, river and sewage treatment plant effluent was established using N,O-bis (trimethylsilyl) trifluoroacetamide (BSTFA) as derivatization reagent combined with gas chromatography–mass spectrometry (GC–MS). Optimal extraction solvent and derivatization factors such as the amount of BSTFA, time, temperature and dissolution solvent were determined experimentally. After extracted by hexane–dichloromethane (1:1, v/v), extracts were evaporated to almost dry, then BSTFA was added to the residue and heated at 90°C for 30min. The remains were dried under a stream of nitrogen and redissolved in hexane. The solution was separated in DB-35MS column, then determined by GC–MS in selected ion mode and full scan monitoring mode, and quantified by external standard method. The working curves were obtained using sample matrix in order to eliminate the matrix interference. Linear range was from 0.02μgL−1 to 30μgL−1. Limits of detection and quantification ranged from 0.0039μgL−1 to 0.0220μgL−1 and 0.0130μgL−1 to 0.0733μgL−1, respectively. Two different spiked levels were measured with 5 parallel tests for each level. The results indicated that the relative standard deviations were less than 14.08%. The method has been applied to lake water, reservoir water, river water and sewage treatment plant effluent. Five OH-PBDEs including 2′-OH-BDE3, 3′-OH-BDE7, 2′-OH-BDE28, 4′-OH-BDE17 and 5′-OH-BDE99 were detected in all the samples collected in Baoding, China. This method is simple, high sensitive, and suitable for simultaneous determination of nine OH-PBDEs in different environmental water.

Food Web Bioaccumulation Model for Resident Killer Whales from the Northeastern Pacific Ocean as a Tool for the Derivation of PBDE-Sediment Quality Guidelines.

Resident killer whale populations in the NE Pacific Ocean are at risk due to the accumulation of pollutants, including polybrominated diphenyl ethers (PBDEs). To assess the impact of PBDEs in water and sediments in killer whale critical habitat, we developed a food web bioaccumulation model. The model was designed to estimate PBDE concentrations in killer whales based on PBDE concentrations in sediments and the water column throughout a lifetime of exposure. Calculated and observed PBDE concentrations exceeded the only toxicity reference value available for PBDEs in marine mammals (1500 μg/kg lipid) in southern resident killer whales but not in northern resident killer whales. Temporal trends (1993-2006) for PBDEs observed in southern resident killer whales showed a doubling time of ≈5 years. If current sediment quality guidelines available in Canada for polychlorinated biphenyls are applied to PBDEs, it can be expected that PBDE concentrations in killer whales will exceed available toxicity reference values by a large margin. Model calculations suggest that a PBDE concentration in sediments of approximately 1.0 μg/kg dw produces PBDE concentrations in resident killer whales that are below the current toxicity reference value for 95 % of the population, with this value serving as a precautionary benchmark for a management-based approach to reducing PBDE health risks to killer whales. The food web bioaccumulation model may be a useful risk management tool in support of regulatory protection for killer whales.

Ultrasound‐assisted dispersive liquid–liquid microextraction combined with gas chromatography‐mass spectrometry in negative chemical ionization mode for the determination of polybrominated diphenyl ethers in water

A simple and economical method for the determination of eight polybrominated diphenyl ethers (BDE-28, 47, 99, 100,153,154,183, and 209) in water was developed. This method involves the use of ultrasound-assisted dispersive liquid-liquid microextraction combined with GC-MS in negative chemical ionization mode. Various parameters affecting the extraction efficiency, including the type and volume of extraction and dispersive solvents, salt concentration, extraction time, and ultrasonic time, were investigated. A volume of 1.0 mL of acetone (dispersive solvent) containing 10 μL tetrachloroethylene (extraction solvent) was injected into 5.0 mL of water samples and then emulsified by ultrasound for 2.0 min to produce the cloudy solution. Under the optimal condition, the enrichment factors for the eight PBDEs were varied from 845- to 1050-folds. Good linearity was observed in the range of 1.0-200 ng L(-1) for BDE-28, 47, 99, and 100; 5.0-200 ng L(-1) for BDE-153, 154, and 183; and 5.0-500 ng L(-1) for BDE-209. The RSD values were in the range of 2.5-8.4% (n = 5) and the LODs ranged from 0.40 to 2.15 ng L(-1) (S/N = 3). The developed method was applied for the determination of eight BPDEs in the river and lake water samples, and the mean recoveries at spiking levels of 5.0 and 50.0 ng L(-1) were in the range of 70.6-105.1%.

Contamination and potential sources of polybrominated diphenyl ethers (PBDEs) in water and sediment from the artificial Lake Shihwa, Korea

Concentrations of polybrominated diphenyl ethers (PBDEs) were determined in water and sediment collected from the artificial Lake Shihwa and surrounding creeks. Total concentrations of 23 PBDE congeners in water and sediment ranged from 0.16 to 11.0ngL−1 and from 1.3 to 18700ngg−1dryweight, respectively. The concentrations of BDE 209 in water and sediment were 1–2 orders of magnitude higher than the total concentrations of other PBDE congeners. The concentrations of total PBDEs and BDE 209 in sediments were the highest compared to previously reported worldwide levels. The highest concentrations of PBDEs in water and sediments were found in creeks near industrial complexes. The PBDE concentrations gradually decreased with increasing distance from the creeks to the inshore and then offshore regions of the lake. BDE 209 was a major congener, accounting for 80% of the total PBDEs in water and sediment, consistent with a high consumption of deca-BDE for the brominated flame retardant market in Korea. Non-parametric multidimensional scaling ordination showed that surrounding creeks are major pathways of PBDE contamination associated with deca-BDE technical mixtures used in industrial complexes around Lake Shihwa. A significant correlation between total organic carbon and total PBDE concentration was found in sediments, and the correlation coefficients for individual PBDE congeners relatively increased from lower to higher brominated congeners.

Temperature-assisted ionic liquid dispersive liquid-liquid microextraction combined with high performance liquid chromatography for the determination of PCBs and PBDEs in water and urine samples

We report a multi-residue pretreatment technique, termed temperature-assisted ionic liquid dispersive liquid-liquid microextraction, and demonstrate its application to simultaneous extraction of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). An ionic liquid was used as the extraction solvent and dispersed into the liquid sample (water, urine) with the help of methanol and at elevated temperature. Parameters such as extraction solvent and its volume, disperser solvent and its volume, extraction time, centrifugation time, salt addition, extraction temperature and sample pH were optimized. Under the optimized conditions, an up to 278-fold enrichment factor and an >83.4% extraction recovery were obtained. A linear relationship is obtained in the range of 0.5–500 ng mL−1. The limits of detection (at S/N = 3) and relative standard deviations (for n = 5) range from 0.1 to 0.4 ng mL−1 and from 1.0% to 5.6%, respectively. The recoveries for water and urine samples additionally spiked with PCBs and PBDEs are between 81.0 and 127.1% and 84.0 and 110.3%, respectively. The method was successfully applied to the determination of PCBs and PBDEs in real river water and in human urine samples.

Picogram per liter level determination of hydroxylated polybrominated diphenyl ethers in water by liquid chromatography–electrospray tandem mass spectrometry

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have obtained increasing attention; however, few analytical methods are available for sensitive identification of these compounds in water. In this paper, we developed a highly sensitive method for simultaneous determination of nine OH-PBDEs in water by using hydrophilic–lipophilic balanced cartridge extraction, silica cartridge purification, and the combination of derivatization with liquid chromatography–electrospray tandem mass spectrometry. The effective sample pretreatment process and greatly increased instrumental sensitivity by derivatization allow for the quantification of nine OH-PBDEs at a method detection limit of 0.04–3.5 pg/L with 1-L wastewater treatment plant effluent or river water. This method was applied to wastewater effluent and river water samples collected in Beijing, China, where two OH-tetraPBDEs were detected at concentrations ranging from 0.63 to 1.0 pg/L (5-OH-BDE-47) and from 0.92 to 1.3 pg/L (6-OH-BDE-47).

Freely dissolved PBDEs in water and porewater of an urban estuary

Polyethylene passive samplers (PE) were deployed in Narragansett Bay, RI, to examine freely dissolved concentrations of polybrominated diphenyl ethers (PBDEs) in surface, bottom, and sediment porewater. PBDE congeners in the water column and porewater were below 3 pg L −1. In the surface water, only PBDE congeners containing up to 5 bromines were detected, while in the deeper water congeners 153 and 154 (6 bromines) were also detected. Activity ratios of surface-bottom water and porewater-bottom water suggested that lower brominated (di-tetra) congeners reached Narragansett Bay from surface waters and sediments. PBDEs in the surface water probably originated from a combination of air–water exchange, freshwater runoff, rivers, and wastewater treatment plants. It is suggested that deep water was the source of higher brominated PBDEs to the Bay implying that the more hydrophobic PBDEs reached depth on particles and/or that these congeners were degraded in sediments. On-going sources supply PBDEs to Narragansett Bay.

Extraction and determination of polybrominated diphenyl ethers in water and urine samples using solidified floating organic drop microextraction along with high performance liquid chromatography

We have developed a method, termed solidification of floating organic drop microextraction (SFOME), for the extraction of polybrominated diphenyl ethers (PBDEs) in water and urine samples, this followed by quantification via HPLC. This method requires very small quantities of organic solvent consumption. It is based on exposing a floating solidified drop of an organic solvent on the surface of aqueous solution in a sealed vial. The organic drop is easily collected with a spatula, molten (at ambient temperature), and then submitted to HPLC. Experimental parameters including extraction solvent and its volume, disperser solvent and its volume, extraction time, ionic strength, stirring speed and extraction temperature were optimized. The enrichment factors of analytes are in the range from 921 to 1,462, and acceptable extraction recoveries (92%–118%) are obtained. The dynamic linear range for five PBDE congeners is in the range of 0.5–75 μg.L−1 and from 5 to 500 μg.L−1 for BDE 209. The correlation coefficients range from 0.9960 to 0.9999. The limits of detection (at S/N = 3) for PBDE congeners vary between 0.01 and 0.04 μg.L−1. This method has been successfully applied to detecting PBDEs in two environmental waters and in human urine.