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ARTICLE in ENVIRONMENTAL SCIENCE & TECHNOLOGY · JULY 2013

Impact Factor: 5.48 · DOI: 10.1021/es4020212 · Source: PubMed

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Virginia Institute of Marine Science

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Brominated Flame-Retardants in Sub-Saharan Africa: Burdens in Inland and Coastal Sediments in the eThekwini Metropolitan Municipality, South Africa Mark J. La Guardia,*,† Robert C. Hale,† and Brent Newman‡

†Department of Environmental & Aquatic Animal Health, Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, Virginia 23062, United States ‡Coastal Systems Research Group, Natural Resources and the Environment, CSIR, Durban, South Africa

*S Supporting Information

ABSTRACT: Brominated flame-retardant (BFR) additives are present in many polymeric consumer products at percent levels. High environmental concentrations have been observed near cities and polymer, textile, and electronics manufacturing centers. Most studies have focused on European, North American, and Asian locales. Releases are likely rising most dramatically in countries with weak environmental and human health regulation and enforcement, demand for electrical and electronic equipment (EEE) is escalating, and importation of waste EEE occurs. Several African countries meet these criteria, but little data are available on burdens or sources. To better understand the extent of BFR environmental dissemination in a southern African urban community, inland and coastal sediments were collected in the eThekwini metropolitan municipality, South Africa, and analyzed for polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), 2-ethylhexyl 2,3,4,5-tretabromophalate (TBPH), 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE), and decabromodiphenyl ethane (DBDPE). BFRs were detected in all samples (n = 45).

Concentration data are presented on total organic carbon (TOC) normalized basis. ΣBFR ranged from 114 to 47 100 ng g−1.

Decabromodiphenyl ether was detected in 93% of samples (mean concentration 3208 ng g−1) followed by TBB at 91% (mean conc. 545 ng g−1). Durban Bay is strongly influenced by urban runoff and tidal hydrology, and sediments therein exhibited ΣPBDE concentrations ranging from 1850 to 25 400 ng g−1 (median conc. 3240 ng g−1). These levels rival those in the heavily impacted Pearl River Delta, China. BFRs likely enter the South African environment during manufacture of BFR-containing products, during and following product use (i.e., after disposal and as a result of materials recycling activities), and from nonpoint sources such as atmospheric fallout and urban runoff. These results underline the need to investigate further the environmental burdens and risks associated with BFRs in developing countries.

■ INTRODUCTION

South Africa is the world’s 28th richest country and Africa’s leading economy. In 2011 the gross domestic product (GDP) was $408.2 billion (USD), up 344%.1 South Africa’s industrial base includes substantial automotive, chemical, and tele-communications sectors (representing 6%, 5%, and 7% of GDP, respectively).2 Along with its expanding economy, South Africa is also in the midst of a consumer product and technological revolution. For example, the number of in-use mobile phones (64 million) now exceeds its population, up from 17% of its adults in 2000 to 76% in 2010.3 The use of mobile computing (e.g., laptops) is also rising, with an expected annual growth of 20% (>650 000 units sold in 2007).4

However, as the demand for electrical and electronic equipment (EEE) grows, so does waste EEE (WEEE). It has been predicted that by 2018 developing nations will dispose of more end-of-service computers than developed countries.5 In addition, nearly 80% of all WEEE generated in developed countries is currently exported to developing nations.6 WEEE recycling is growing in Africa, facilitated by low labor costs and high demand for raw materials. It is estimated that 1.3 million metric tonnes (MT) of WEEE is disposed annually in the sub- Saharan countries of Benin, Cote d’ Ivoire, Ghana, Liberia, and Nigeria.7 WEEE contains both valuable and hazardous materials. The environmental release of toxicants (e.g., chlorinated dioxins and heavy metals) from unregulated WEEE salvaging has been observed.8 This is of concern for countries with weak environmental and human health practices.

Africa’s sub-Saharan region ranked last according to Yale University’s 2010 Environmental Performance Index (EPI) of 163 countries on 25 performance indicators covering environ-

Received: May 6, 2013 Revised: July 26, 2013 Accepted: July 30, 2013 Published: July 30, 2013

Article pubs.acs.org/est

© 2013 American Chemical Society 9643 dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−9650 pubs.acs.org/est mental public health and ecosystem vitality (http://www.

epi2010.yale.edu). Of the 41 sub-Saharan countries, South Africa’s EPI ranked 15th and when compared to 16 other countries with similar GDP/capita, ranked last.

Plastics account for 21% by weight of WEEE9 and may be recycled and reformed into new products.10 Alternatively, plastics are often burned to facilitate access to the valuable metals or simply for debris disposal. WEEE-associated plastics typically contain persistent, bioaccumulative chemicals such as polybrominated diphenyl ethers (PBDEs).11 PBDEs are brominated flame retardants (BFRs) added to textiles and polymers used in electronics and furniture. Two PBDE formulations, i.e., Penta-BDE and Octa-BDE, were added to the Persistent Organic Pollutants (POPs) list of the Stockholm Convention in May 2009, restricting their production.12 In July 2008 the third and most widely used PBDE formulation, deca- BDE, was banned in EEE in the EU 13 and is scheduled to be phased out of U.S. production by the end of 2013.14

Replacement brominated and nonbrominated FR additives have begun to supplant PBDEs in products and hence may become more abundant in the environment. Also, outdated EEE discarded by the developed world is exported and sold in the developing world, 7 these near-end-of-lifecycle EEE can contain harmful chemicals (i.e., PBDEs) now prohibited from newly manufactured EEE. Some WEEE exporters have exploited a loophole in the UNEP Basel Convention which prohibits the trans-boundary export of WEEE, but allows for the export of functioning or reparable electronics. Some deceptive exporters have padded shipments with up to 75% irreparable electronics (i.e., WEEE).15 The United States, the world’s largest WEEE producer, is expected to produce over 3 million MT annually by 2020 and has not yet ratified the Basel Convention.16 With the exception of cathode ray tubes (e.g., computer monitors), this has allowed U.S. shippers to legally export WEEE wherever desired, as long as the export goal is declared as “recycling”.15

Elevated BFR levels have been associated with densely populated urban centers, in turn correlated with the amount of BFR containing products therein.17−19 However, while Europe was the world’s third largest consumer of PBDEs,20 air concentrations of these chemicals detected off the sub-Saharan coast of West Africa (0.95−3.10 pg m−3) were reported to be comparable to those off Europe’s coast (1.13−3.30 pg m−3).21

This was attributed to EEE and WEEE’s salvaging. Seawater samples taken from the southern hemisphere Agulhas Current retroflection region (∼400 miles southwest of Cape Town, South Africa) exhibited PBDE levels >2.5 times those detected in the English Channel (2.19 and 0.81 pg L−1, respectively).21

PBDEs have also been detected in South African sediments,22 sewage sludge and wastewater effluent,23 landfill leachate,24 house dust,25 and human breast milk.26 According to Frost and Sullivan (2010), the South African plastics manufacturing sector is the largest consumer of BFRs, valued at approximately

2.5 million (USD).27 However, this only accounts for <0.04% of the global 2005 BFR consumption. In contrast the U.S.

represented 38% (564 000 MT), Europe 33% (489 000 MT), Japan 10% (160 000 MT), and other Asian countries 18% (269 000 MT) of worldwide demand.28 Therefore, emissions of the chemical product by South African manufacturers may be a minor source, but emissions from components produced elsewhere and assembled in South Africa, those from in-use or discarded goods or from recycled materials (e.g., vehicles, WEEE), may be a more significant source.

Recently another BFR (i.e., hexabromocyclododacane (HBCD)), primarily used in polystyrene insulation boards and to a lesser extent textiles, has been detected in South African bird eggs 29 and human breast milk from Ghana.30

HBCD is also considered a persistent, bioaccumulative, and toxic (PBT) chemical. Exposure to HBCD may cause reproductive, developmental, and neurological disorders.31,32

Like PBDEs, HBCD will be phased-out of European commerce by 2015 under EU’s REACH program. In the U.S., HBCD and 20 additional flame retardants are now under evaluation by the EPA.33 According to the EPA, “These chemicals were selected because they are likely to persist in the environment, bioaccumulate in people and/or have high exposure poten-tial...”. These flame-retardants likely are also entering the African environment. Therefore, to gain a better understanding of BFR environmental dissemination in developing countries of the Southern Hemisphere, sediments from urbanized inland to coastal waterways in the eThekwini metropolitan municipality, South Africa were evaluated for BFR burdens and patterns.

■ EXPERMENTAL SECTION

Inland and coastal surficial sediments (n = 45) were collected in August 2011 from Durban Bay and 13 rivers in the eThekwini metropolitan municipality, South Africa. A map of the municipality and Durban Bay along with sample IDs, locations (latitude and longitude), river/bay names, and site associated population densities are listed in the Supporting Information (Figure S1 and Table S1). The municipality is located in the KwaZulu-Natal Province on the northeast coast of South Africa, which includes Durban, the third largest city in South Africa and home to the Port of Durban (Durban Bay), the largest container terminal in the Southern Hemisphere. The combined municipality (land area 2292 km2) is the largest city (population 3.5 million) on Africa’s east coast, with a population density of 1,513 inhabitants/km2. Sediments were collected using a van Veen grab and stored in precleaned glass jars at <0 °C. Samples were freeze-dried, homogenized, and stored in glass jars at <0 °C until analyzed.

Details of the methods for the analysis of polybrominated diphenyl ethers (PBDEs) and the alternative-BFRs (alt-BFRs) 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB), 2-ethylhexyl 2,3,4,5-tretabromophalate (TBPH), 1,2-bis (2,4,6-tribromophe-noxy) ethane (BTBPE), and decabromodiphenyl ethane (DBDPE) by gas chromatography (GC) and three α-, β-, and γ-hexabromocyclododecane (HBCD) isomers by liquid chromatography (LC) mass spectrometry are described by La Guardia et al..34 The method was modified to permit determination of these BFRs in a single extract by ultra-performance liquid chromatography (UPLC)/atmospheric pressure photoionization (APPI) tandem mass spectrometry (MS/MS). The 18 targeted BFRs, their acronyms, and chemical formulations are listed in Table S2. All BFR analytical standards were supplied by AccuStandard, Inc. (New Haven, Ct., U.S.A.). A good agreement between analytical results generated by GC high-resolution mass spectrometry and LC APPI-MS/MS has been previously demonstrated for these BFRs and an additional 18 halogenated flame-retardants in fish tissue extracts.35 For BFRs in sediments, the method was validated by the analysis of a BFR-fortified matrix (sodium sulfate (NaSO4)) and also the standard reference material (SRM) 1944 (New York/New Jersey Waterway Sediment, National Institute of Standards and Technology (NIST)). BFR-fortified matrix recoveries ranged from 86 and 121% (Table S3)

Environmental Science & Technology Article dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509644 http://www.epi2010.yale.edu http://www.epi2010.yale.edu and the relative percent difference (RPD) for ΣPBDEs and ΣHBCDs in SRM 1944 were compared to NIST certified values. Their RPD was 35% and 58%, respectively (Table S4).

This is the first reported values for alt-BFRs (i.e., TBB, TBPH and BTBPE) in SRM 1944 (Table S4). DBDPE was not detected above the detection limit, consistent with previously reported literature data.36 Briefly, ∼20 g (dry weight) of the sample was subjected to accelerated solvent extraction (ASE 200, Dionex, Sunnyvale, CA, U.S.A.) with dichloromethane (DCM). A surrogate standard (200 ng of 2,3,4,4′,5,6-hexabromodiphenyl ether (BDE-166); Cambridge Isotope Laboratories, Inc., Andover, MA) was added to each sample prior to extraction. Extracts were purified by size exclusion chromatography (SEC, Envirosep-ABC, 350 × 21.1 mm2 column; Phenomenex, Torrance, CA, U.S.A.). Each post-SEC extract was solvent exchanged to hexane, reduced in volume and added to the top of a solid phase 2-g silica glass extraction column (Isolute, International Sorbent Tech.; Hengoed Mid Glamorgan, U.K.). Each column was eluted with 3.5 mL of hexane (fraction one), followed by 6.5 mL of 60:40 hexane/ DCM and 8 mL of DCM (fraction two). The second fraction, containing BFRs, was reduced in volume and solvent exchanged to methanol. Decachlorodiphenyl ether (DCDE; 400 ng; Ultra Scientific, North Kingstown, RI, U.S.A.) was then added as the internal standard. Analytes in these purified extracts were chromatographically separated by UPLC (Acquity UPLC, Waters Corporation, Milford, MA, U.S.A.) operated in the gradient mode (100% methanol (A1) and 100% water (B1)), equipped with a C18 UPLC analytical column (Acquity UPLC BEH C18, 1.7 μm, 2.1 × 150 mm2, Waters Corp.). Analytes were ionized by APPI, the dopant (acetone) was introduced at 150 μL/min by a liquid chromatography pump (LC-20AD, Shimadzu Corporation, Kyoto, Japan), and product ions were detected by a triple quadrupole mass spectrometer (3200 QTrap, AB Sciex, Framingham, MA, U.S.A.) operated in the multiple reaction monitoring (MRM) mode. For BFRs transition ions m/z 79 ([79Br]−) and 81([81Br]−), and m/z 35 ([35Cl]−), 37([37Cl]−) for DCDE were used for quantitation. Further details of the sample preparation and UPLC APPI-MS/MS operating conditions are listed in Table S5. Along with BFR-fortified matrix and SRM analysis, method performance was validated by processing blanks and duplicates with each sample set and monitoring for surrogate recovery of each sample. BFRs were not observed in the blanks above the detection limit (>0.6 ng g−1 dry weight (dw). Surrogate recoveries ranged from 73 to 132% and are listed along with sample results in Table S6. Duplicate analysis results are listed in Table S3. Total organic carbon (TOC) was determined by combustion followed by infrared detection (CE-440, Exeter Analytical, North Chelmsford, MA) and results are listed in Table S6. Statistical analyses were performed using Minitab

16.1.0 for Windows. Regression analysis was used to determine the relationship (P < 0.05) between ΣBFR concentration and population density (inhabitants/km2).

■ RESULTS AND DISCUSSION

Multiple BFRs were observed in surficial sediments from rivers, estuaries and Durban Bay. At least one of the 18 targeted BFRs was detected in each of the 45 samples (Table S6); indicating that BFRs are ubiquitous within the region. Frequency of detection was highest for alt-BFRs (98%), followed by ΣPBDEs (93%) and ΣHBCD (69%) (Table 1). The major constituent of the Deca-formulation, BDE-209,37 was the most frequently detected individual BFR (93%) followed by TBB (91%). The frequency of detection for ΣPenta-BDE was 67% (Table 1).

This higher rate for the alt-BFR TBB may be a consequence of the 2004 discontinuation of Penta-BDE and its replacement with TBB.38 Although the alt-BFRs had a higher frequency of detection, PBDEs were typically the dominant concentration contributor, as indicated by a 58.8% mean percent composition (Figure 1a). PBDE concentrations were followed by ΣHBCD (28.2%) and Σalt-BFR (12.9%). BDE-209 contributed 85.5% to ΣPBDEs, whereas ΣPenta-BDEs (BDE-47, −100, −99 and −153) contributed 11.3% (Figure 1b, mean concentration 423 ng g−1, Table 1). PBDE congener profiles within these sediments generally resembled the profiles of technical products with BDE-209 being the dominant Deca-BDE congener at 97% (mean) and 3% for BDE-206. The Penta-profiles within these sediments were dominated by BDE-47 and -99, at 41% and 49%, respectively. There is a lack of BFR production and usage available for countries in the Southern Hemisphere. However, in Europe, 7500−10 000 MT of Deca-was sold in 2011 (VECAP 2012).39 Prior to the Penta- and Octa-BDE 2004 production restrictions, the global 2001 demand for Deca-BDE was 56,100 MT and was followed by Penta- and Octa- at 7500 and 3790 MT, respectively.20 It has been observed that the biota-sediment accumulation factors (BSAFs) for PBDEs decrease for congeners with greater than six bromines.34 This indicates a lower uptake rate for the BDE- 209 in these sediments. However, BDE-209 has been observed to undergo debromination in the aquatic environment and hence less brominated degradates may contribute to the cumulative PBDE bioaccumulation and toxicity.40

For HBCD, sediment profiles (Figure 1c) were dominated by γ-HBCD (57.1%) followed by α-HBCD (33.3%) and β-

Table 1. Sediment BFR (Congener and Totals) % Detection Rate (%DR) and Concentration (ng g−1, TOC) Range, Median and Meana analytes %DR range median mean

BDE-28 0% nd nd nd BDE47 49% nd to 3790 nd 174 BDE-66 0% nd nd nd BDE-85 0% nd nd nd BDE-100 7% nd to 246 nd 7 BDE-99 67% nd to 3050 47 209 BDE-154 0% nd nd nd BDE-153 18% nd to 588 nd 33 Σpenta-BDEs 67% nd to 7430 64 423 BDE-183 33% nd to 707 nd 35 BDE-206 47% nd to 1360 nd 84 BDE-209 93% nd to 44 500 784 3208 Σocta- and deca-BDEs 93% nd to 45 900 837 3320 ΣPBDEs 93% nd to 46 300 1390 3750 TBB 91% nd to 13 900 150 545 TBPH 60% nd to 899 54 96 BTBPE 13% nd to 616 nd 34 DBDPE 62% nd to 1840 70 171 Σalt-BFRs 98% nd to 13 900 383 825 α-HBCD 62% nd to 10 400 133 600 β-HBCD 42% nd to 4970 nd 173 γ-HBCD 67% nd to 18 700 146 1030 ΣHBCDs 69% nd to 27 500 349 1800 ΣBFRs 100% 114−47 100 2,280 6380 and < 0.6 ng g‑1 dry weight.

Environmental Science & Technology Article dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509645

HBCD (9.6%). Annual European usage of HBCD was 10 000− 12 500 MT in 2011, up from 7500−10 000 MT in 2009 and

2010.39 The frequency of detection (Table 1) for the ΣHBCD

(69%) was lower than the other two BFR classes: ΣPBDEs 93% and Σalt-BFR 98%. However, the mean ΣHBCD concentration, 1800 ng g−1 (maximum 27 500 ng g−1) was >4-times the mean concentration of ΣPenta-BDE, 423 ng g−1 (max conc. 7430 ng g−1). (Concentration data are presented on total organic carbon (TOC) normalized basis.) This could be of concern considering the BSAF for HBCD (log BSAF ≈ 1) in mollusks is similar to BSAFs of BDE-47 and −99, dominant constituent congeners of the restricted Penta-BDE formulation. Each of the alt-BFRs was detected in these sediments. Their profiles (Figure 1d) were dominated by TBB (64%), DBDPE (20%), TBPH (11%), and BTBPE (4.0%).

The sediment ΣBFR concentrations in the eThekwini metropolitan municipality ranged from 114 to 47,100 ng g−1

(Table 1). Traversing the municipality north to south it is evident that BFR concentrations increased near the urban center, with six sites exceeding the mean (ΣBFR 6380 ng g−1, indicated by the dash line in Figure 2) by several fold.

Excluding these sites (i.e., MNG7b, DBAY6, UMB2, UMB1, AMA1, and ISI5) from the data set, regression analysis of the remaining sites (n = 39) indicated a weak relationship between population density and ΣBFRs (r2 = 0.14). However, this relationship was statistically significant (P = 0.038). BFR containing products used domestically are one potential source.17−19 The lowest BFR sediment concentrations were detected in rural areas. These estuarine sites are located in the municipality’s northern end (Tongaat (1a), Mdloti (1b) and Mhlanga (1c)) and southern end (Amanzimtoti (8a), Umgababa (8b), Umsimbazi (8c), and Lovu (8d), ΣBFR < 741 and <1010 ng g−1, respectively (Figure 2). The municipality is a mix of residential and industrial areas that

Figure 1. Mean percent contribution of (a) ΣBFRs, (b) PBDEs, (c) HBCDs, and (d) alt-BFRs sediment concentration.

Figure 2. ΣBFR (ΣHBCD, Σalt-BFRs, and ΣPBDEs) concentrations (ng g−1, TOC) in sediment samples from the eThekwini metropolitan municipality in order of river location (north to south) and river sample location (inland to coast). (*Denotes sample sites located downstream from a wastewater treatment works outfall.) River and Bay IDs: 1a-Tongaat R., 1b-Mdlota R., 1c-Mhlanga R., 2-Mngeni R., 3-Durban Bay, 4a-Umbilo R., 4b-Umhlatuzana R., 5-Amanzimnyama R., 6-Isipingo R., 7-Mbokodweni R., 8a-Amanzimtoti R., 8b-Umgababa R., 8c-Umsimbazi R., 8d-Lovu R.

dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509646 range from densely populated informal settlements to lavish tourist resorts, intertwined with small business and large international manufacturing and chemical producers. To facilitate drainage and prevent inland flooding most of the natural river systems within the urbanized area have been canalized to receive runoff during storm events. These systems have also become catchments for trash and illegal dumping. A number of wastewater treatment plants also discharge into the rivers. All only perform primary treatment of wastewater. ΣBFR concentrations exceeding the mean were not detected down-stream of the outfalls (sample sites #TONG, MDLO, MHLA, MNG14, MNG13, MNG9, UMB5, MB04 and MB02), although this can to some extent be explained by the fact that the rivers are relatively fast flowing and the sediment has a low organic fraction (Figure 2). The highest ΣBFR level, 47 100 ng g−1, was detected downstream from the Umgeni Business Park (#MNG7b). The Business Park is divided by the Mngeni River, which flows through an area containing a mix of commercial and manufacturing industries. BDE-209 was dominant (44 500 ng g−1), contributing 95% to the ΣBFRs.

This was the furthest upstream collection site for this river.

Hence, the source was not delineated. However, the five sites located downstream (sites #MNG6, 5, 3, 2 and 1) all had BDE- 209 levels greater than the municipality’s median BDE-209 value of 784 ng g−1. Site #ISI5, located in another business district on the canalized lower reaches the Isipingo River, exhibited the fifth highest ΣBFR concentration at 22 300 ng g−1. BDE-209 was the dominant flame retardant (11 500 ng g−1), followed by γ-HBCD and Σpenta-BDE (3860 and 2760 ng g−1, respectively). This site drains a large industrial area where automotive manufacturing and salvaging takes place. A large pile of scrap automotive interiors (e.g., polyurethane foam) was observed at this site (Google Earth, imagery date June 16, 2012). This site is also located adjacent to a large commercial WEEE recycler.

Another potential BFR source (sites #UMB1 and #UMB2) is located on the Umbilo and Umhlatuzana rivers, which flow through the central part of the eThekwini municipality. These rivers drain mostly urban (70%) areas. The remainder of the drainage is primarily bushland, grassland, and forest. The rivers converge just before the entering Durban Bay, where the sixth highest ΣBFR sediment concentration was detected (#UMB1, 15 600 ng g−1). This site is located in Bayhead Marshalling Yard, a large rail yard servicing the Bay. ΣBFRs were dominated by BDE-209, at 14 400 ng g−1. However, site #UMB2 located on the Umbilo River upstream from site #UMB1 had the fourth highest ΣBFR concentration (24 000 ng g−1), dominated by TBB (13 900 ng g−1), followed by ΣPenta-BDEs (7430 ng g−1).

TBB is a component of the commercial mixture Firemaster-550 (Chemtura Corp. (USA)) which also contains TBPH at a TBB/TBPH ratio of 4:1. TBPH was detected in this sample at 899 ng g−1, producing a TBB/TBPH ratio of 16:1. This suggests a different chemical composition or manufacturer or different relative fate or transport for these flame-retardants.

This was hypothesized by Stapleton et al., who reported TBB/ TBPH ratios ranging from 1:20 to 50:1 in indoor dust samples.41 The third highest ΣBFR site (#AMA1, 36 300 ng g−1) was on the Amanzimnyama River where it passes through the Bayhead Marshalling Yard, before flowing into the southern side (extreme upper reach) of Durban Bay. The ΣHBCD level here (27 500 ng g−1) was the highest reported in these sediments and contributed 76% of the ΣBFRs. The second highest ΣBFR concentration (47 000 ng g−1) was located in

Durban Bay (#DBAY6) at the mouth of a culvert draining surface runoff from area consisting of a mix of industrial and mainly residential concerns. At this site, BDE-209 was again the dominant BFR (24 500 ng g−1). However, it also exhibited the second highest HBCD concentration in our study (21 100 ng g−1). The HBCD technical formula is dominated by the γ-isomer and exhibits a α:γ ratio of 0.09. Similar ratios have been observed in abiotic media such as sediments, soils and landfill leachate.31 Enrichment of α-HBCD may occur following exposure of HBCD-treated textiles and thermoplastics to elevated temperatures (e.g., ≥160 °C)42 or through bio-transformation. 31 In finished textiles the α:γ ratio has been reported to be 0.52 to 1.06, which indicates enrichment of the α-isomer by preferential absorption by the product of the α-isomer or γ-isomer thermal rearrangement.43 At this site (#DBAY6) the total HBCD profile in sediments was dominated by γ-HBCD at 88.6% followed by α-HBCD at 9.0% and 2.1% for β-HBCD, producing a α:γ ratio of 0.10;

indicating the HBCD technical product as the likely source.

The α:γ ratio at the other sites within the municipality ranged from 0.21 to 4.28. Both HBCD and BDE-209 are commonly used to treat textiles. Hence, a facility making or using textiles might have been a contributor here.

Within and near to Durban Bay (sites #AMA1, UMB1, and

DBN1 through 7), the mean ΣBFR sediment concentration (15,300 ng g−1 TOC) was 2-times higher than other sediments from eThekwini municipality sites. The Bay has an area of 8.29 km2 and receives inputs from the Umbilo, Umhlatuzana and Amanzimnyama rivers and urban runoff from culverts draining the city of Durban. The total catchment area of all three rivers is 195 km2 and falls entirely within the eThekwini municipal boundary. All three catchments are canalized at their lower reaches and highly transformed. Over 70% of the catchment is considered urban (23% natural) and 20% of this area consists of impervious surfaces. These factors have all altered the Bay’s hydrology causing present day runoff into the Bay to be 74% greater than it was prior to its human disturbance.44 PBDEs, HBCDs, and alt-BFRs were all detected in sediment at each Bay sample (n = 7). The ΣBFR ranged from 2900 to 47 000 ng g−1. BDE-209 was the dominant BFR and concentrations ranged from 1740 to 24 500 ng g−1. With the exception of sites #DBAY6 and #DBN3, BFR concentrations in the Bay were fairly consistent between locales, from 2900 to 7240 ng g−1.

This suggests a likely common source. However, a wider range in concentrations was observed for HBCD (349 to 3640 ng g−1), possibly indicating a more localized source (e.g., textile manufacturing). The HBCD α:γ-isomer ratio varied from 0.64 to 3.21, which may indicate releases from finished products (e.g., textiles or building insulation material) washing into the Bay from the urban environment. Except for sample #DBN1;

TBB, TBPH, and DBDPE were detected in each of the Bay’s samples, ranging from 363 to 1460 ng g−1. (TBB was not detected in sample #DBN1 above the detection limit of 0.6 ng g−1, dry weight.)

Compared to other aquatic systems around the world, Durban Bay’s PBDE sediment concentrations were relatively high, especially considering the reported lack of flame-retardant demand in Africa. Demand figures for 2001 suggested that North America accounted for 95% of the global Penta-BDE consumption and 44% of that for Deca-BDE.20 Studies have revealed that PBDE concentrations in marine biota from California’s coast are among the highest in the world, doubling as rapidly as every 2−4 years in some species, presumably dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509647 exacerbated by California’s stringent flammability standard for polyurethane foam (Technical Bulletin 117 (TB117)).45

However, the ΣPBDEs (i.e., ΣBDE-28, −47, −99, −153, and −209) detected in Durban Bay sediments (17 to 497 ng g−1, dw (median concentration 131 ng g−1, dw)) were an order of magnitude higher than those of San Francisco Bay (1.68 to 6.76 ng g−1, dry weight (dw) (median 3.51 ng g−1, dw)) (Figure 3).46 PBDE concentrations in Durban Bay also rivaled those reported in the Pearl River Estuary, China (1.17 to 127 ng g−1, dw (median 9.7 ng g−1, dw)) (Figure 3). The two major rivers of the Pearl River Delta (PRD), the Zhujiang and Dongjiang, flow through the world’s most densely urbanized region (population 120 million) and a major electronics manufactur-ing center. The median PBDE sediment concentrations in these rivers were reported as 718 and 1250 ng g−1 dw, respectively (Figure 3). The city of Dongguan is considered to be the largest manufacturing base of electronic products in the PRD region and is estimated to produce one of every three computers worldwide.47 If the levels of BFRs detected within Durban Bay were associated with manufacturing, global markets would indicate a large manufacturing presence in South Africa. Therefore, particulates carried by the three rivers (i.e., Umbilo, Umhlatuzana, and Amanzimnyama) that enter Durban Bay from the south, after washing through large residential and industrialized areas, are probable proximate sources. Particulate material is deposited, because of weak currents and long water residence time in the upper part of the Bay due to a unique hydromorphology. The Bay’s opening is in opposition to the south-flowing Mozambique Current of the Indian Ocean. This sets up littoral drifts, moving sand northward along the East African cost, forming sandbars that have historically closed the Bay. These factors (i.e., urban runoff and the Bay’s hydromorphology) may account for flame-retardant levels exceeding those found in other urban bays (e.g., San Francisco Bay). Our findings suggest that, as local demand for polymer products and electronics escalates and if the area remains a center for WEEE, BFR concentrations may increase in the sub-Saharan environment. This underlines the need to further investigate the environmental burdens and risks associated with BFR use in developing countries of the Southern Hemisphere.

■ ASSOCIATED CONTENT

*S Supporting Information Additional details on instrument methodology, quality control/ quality assurance, duplicate analysis, spiking experiments, and their results along with Figure S1 and Tables S1−S6. This material is available free of charge via the Internet at http:// pubs.acs.org.

■ AUTHOR INFORMATION

Notes The authors declare no competing financial interest.

■ ACKNOWLEDGMENTS

Funding for this research provided by the Water Research Commission (Grant K5/1977), CSIR (Grant PG 4801) and National Research Foundation (Grant 74305) of South Africa is gratefully acknowledged. This is Contribution No. 3299 from the Virginia Institute of Marine Science, College of William & Mary.

■ REFERENCES

(1) The World Bank, South Africa http://data.worldbank.org/ country/south-africa (accessed May 3, 2013).

(2) South Africa, Brand South Africa Country Portal http://www.

southafrica.info/business/economy/sectors/manufacturing.htm#.

UVsUFVeU_zA (accessed May 3, 2013).

(3) U.S. CIA, The World Factbook https://www.cia.gov/library/ publications/the-world-factbook/geos/sf.html (accessed May 3, 2013).

(4) Finlay & Liechti e-Waste Assessment South Africa (2008) eWASA. Finlay & Liechti 2008, http://ewasteguide.info/Finlay_ 2008_eWASA (accessed May 3, 2013).

(5) Yu, J.; Williams, e.; Ju, M.; Yang, Y. Forecasting global generation of obsolete personal computers. Environ. Sci. Technol. 2010, 44, 3232− 3237.

(6) Hicks, C.; Dietmar, R.; Eugster, M. The recycling and disposal of electrical and electronic waste in China − legislative and market responses. Environ. Impact. Assess. Rev. 2005, 25, 459−471.

(7) United Nations Environment Programme (UNEP), Secretariat of the Basel Convention, Where are WEee in Africa? 2011, http://www.

base l . in t/ Implementa t ion/Technica lAss i s tance/EWaste/ EwasteAfricaProject/Publications/tabid/2553/Default.aspx (accessed May 3, 2013).

(8) Leung, A. O.; Zheng, J.; Yu, C. K.; Wong, C. K. C.; Cai, Z.;

Wong, M. H. Polybrominated diphenyl ethers and polychlorinated

Figure 3. ΣPBDE (sum of BDE-28, −47, −99, −153, and −209) sediment concentrations (ng g−1, dry weight) for Durban Bay (South Africa), San Francisco Bay (U.S.A.), and Pearl River Delta (PRD), China.

Environmental Science & Technology Article dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509648 http://pubs.acs.org http://pubs.acs.org http://data.worldbank.org/country/south-africa http://data.worldbank.org/country/south-africa http://www.southafrica.info/business/economy/sectors/manufacturing.htm#.UVsUFVeU_zA http://www.southafrica.info/business/economy/sectors/manufacturing.htm#.UVsUFVeU_zA http://www.southafrica.info/business/economy/sectors/manufacturing.htm#.UVsUFVeU_zA https://www.cia.gov/library/publications/the-world-factbook/geos/sf.html https://www.cia.gov/library/publications/the-world-factbook/geos/sf.html http://ewasteguide.info/Finlay_2008_eWASA http://ewasteguide.info/Finlay_2008_eWASA http://www.basel.int/Implementation/TechnicalAssistance/EWaste/EwasteAfricaProject/Publications/tabid/2553/Default.aspx http://www.basel.int/Implementation/TechnicalAssistance/EWaste/EwasteAfricaProject/Publications/tabid/2553/Default.aspx http://www.basel.int/Implementation/TechnicalAssistance/EWaste/EwasteAfricaProject/Publications/tabid/2553/Default.aspx dibenzo-p-dioxins and dibenzofurans in surface dust at an e-waste processing site in southeast China. Environ. Sci. Technol. 2011, 45, 5775−5782.

(9) Ongondo, F. O.; Williams, I. D.; Cherrett, T. J. How are WEEE doing? Waste Management 2011, 31, 714−730.

(10) e-Waste, Hewlett-Packard e-Waste Africa, 2007−2008 http:// ewasteguide.info/node/4166 (accessed May 3, 2013).

(11) Wag̈er, P. A.; Schuep, M.; Müller, E.; Gloor, R. RoHS regulated substances in mixed plastics from waste electrical and electronic equipment. Environ. Sci. Technol. 2012, 46, 628−635.

(12) Stockholm Convention, The 9 new POPs under the Stockholm Convention. 2009. http://chm.pops.int/Implementation/NewPOPs/ TheNewPOPs/tabid/672/Default.aspx (accessed May 3, 2012).

(13) Betts, K. Court bans widely used flame retardant. Environ. Sci.

Technol. 2008, 42, 3910.

(14) U.S. EPA, DecaBDE phase-out Initiative. 2010, http://www.epa.

gov/oppt/existingchemicals/pubs/actionplans/deccadbe.html (ac-cessed May 3, 2013).

(15) Schmidt, C. W. Unfair Ttrade e-Waste in Africa. Envron. Health Perspectives 2006, 114, A232−A235.

(16) U.S. EPA Chapter V − Basel Convention, (Last update: July 24, 2012) http://www.epa.gov/osw/hazard/international/basel3.htm (ac-cessed May 3, 2013).

(17) Butt, C. M.; Ikonomou, M. G.; Ter Schure, A. F. H. Spatial distribution of polybrominated diphenyl ethers in southern Ontario and measured in indoor and outdoor window organic films. Environ.

Sci. Technol. 2004, 38, 724−731.

(18) Skinner, L. C. Distribution of polyhalogenated compounds in Hudson river (New York, USA) fish in relation to human uses along the river. Environ. Pollut. 2001, 159, 2565−2574.

(19) Sun, J.-L.; Chen, Z.-X.; Ni, H.-G.; Zeng, H. PBDEs as indicator chemicals of urbanization along an urban/rural gradient in South China. Chemosphere 2013, in press. (http://dx.doi.org/10.1016/j.

Chemosphere.2013.01.036) (accessed May 3, 2013)

(20) Law, R. J.; Allchin, C. R.; de Boer, J.; Covaci, A.; Herzke, D.;

Lepom, P.; Morris, S.; Tronezynski, J.; de Wit, C, A. Levels and trends of brominated flame retardants in the European environment.

Chemosphere 2006, 64, 187−208.

(21) Xie, Z.; Möller, A.; Ahrens, L.; Sturm, R.; Ebinghaus, R.

Brominated flame-retardants in seawater and atmosphere of the Atlantic and the southern ocean. Environ. Sci. Technol. 2011, 45, 1820− 1826.

(22) Olukunle, O.; Okonkwo, J.; Kefeni, K.; Lupankwa, M.

Concenttration of polybrominated diphenyl ethers in sedimants from Jukskei river, Gauteng, South Africa. Bull. Environ. Contam.

Toxicol. 2012, 88, 461−466.

(23) Daso, A. P.; Fatoki, O. S.; Odendaal, J. P.; Olujimi, O. O.

Occurrence of selected polybrominated diphenyl ethers and 2,2′,4,4′5,5′-hexabromobiphenyl (BB-153) in sewage sludge and effluent samples of a wastewater-treatment plant in Cape Town, South Africa. Arch. Environ. Contam. Toxicol. 2012, 62, 391−402.

(24) Odusanya, D. O.; Okonkwo, J. O.; Botha, B. Polybrominated diphenyl ethers (PBDEs) in leachates from selected landfill sites in South Africa. Waste Manage. 2009, 29, 96−102.

(25) Kebede, K. K.; Okonkwo, J. O. Analysis of major congeners of polybromobiphenyls and polybromodiphenyl ethers in office dust using high resolution gas chromatography-mass spectrometry. Chemo-sphere 2012, 87, 1070−1075.

(26) Darnerud, P. O.; Aune, M.; Larsson, L.; Lignell, S.; Mutshatshi, T.; Okonkwo, J.; Botha, B.; Agyei, N. Levels of brominated flame-retardants and other persistent organic pollutants in breast milk samples from Limpopo province, South Africa. Sci. Total Environ.

2011, 409, 4048−4053.

(27) Frost & Sullivan, Chemical Materials and Foods Research Unit, Cape Town, South Africa − An investigation into the extent of manufacture, use, import and export of new chemicals listed in terms of the Skholm and Rotterdam conventions. December 13, 2010.

http://www.nedlac.org.za/media/94760/chemicals_impact_ assessment_final_consolidated_report_-_2010.pdf (accessed May 3, 2013).

(28) Norwegian Pollution Control Authority, Current state of knowledge and monitoring requirements − Emerging “new” brominated flame retardants in flame retarded products and the environment (TA-2462/2008), 2009, http://www.klif.no/ publikasjoner/2462/ta2462.pdf (accessed May 3, 2013).

(29) Polder, A.; Venter, B.; Skaare, J. U.; Bouwman, H.

Polybrominated diphenyl ethers and HBCD in bird eggs of South Africa. Chemosphere 2008, 73, 148−154.

(30) Asante, K. A.; Adu-Kumi, S.; Nakahiro, K.; Takahashi, S.; Isobe, T.; Sudaryanto, A.; Devanathan, G.; Clarke, E.; Anse-Asare, O. D.;

Dapaah-Siakwan, S.; Tanabe, S. Human exposure to PCBs, PBDEs and HBCDs in Ghana; Temporal variation, sources of exposure and estimation of daily intakes by infants. Environ. Int. 2011, 37, 921−928.

(31) Covaci, A.; Gerecke, A. C.; Law, R. J.; Voorspoels, S.; Kohler, M.; Heeb, N. V.; Leslie, H.; Allchin, C. R.; de Boer, J.

Hexabromocyclododecanes (HBCDs) in the environment and humans: A review. Environ. Sci. Technol. 2006, 40 (12), 3679−3688.

(32) van der Ven, L. T. M.; van de Kuil, T.; Leonards, P. E. G.; Slob, W.; Lilienthal, H.; Litens, S.; Herlin, M.; Hak̊ansson, H.; Cantoń, R. F.;

van den Berg, M.; Visser, T. J.; van Loveren, H.; Vos, J. G.; Piersma, A.

H. Endocrine effects of hexabromocyclododecane (HBCD) in a one −generation reproduction study in Wistar rats. Toxicol. Lett. 2009, 185, 51−62.

(33) U.S. EPA, EPA Announces Chemicals for Risk Assessment in 2013, Focus on Widely Used Flame Retardants, 2013, http:// y o s e m i t e . e p a . g o v / o p a / a d m p r e s s . n s f / 0 / C6BE79994C3FD08785257B3B0054E2FA (accessed May 3, 2013).

(34) La Guardia, M. J.; Hale, R. C.; Harvey, E.; Mainor, M.; Ciparis, S. In-situ accumulation of HBCD, PBDEs, and several alternative flame-retardants in the bivalve (Corbicula f luminea) and gastropod (Elimia proxima). Environ. Sci. Technol. 2012, 46, 5798−5805.

(35) Zhou, S. N.; Reiner, E. J.; Marvin, C.; Kolic, T.; Riddell, N.;

Helm, P.; Dorman, F.; Misselwitz, M.; Brindle, I. D. Liquid chromatography-atmospheric pressure photoionization tandem mass spectrometry for analysis of 36 halogenated flame-retardants in fish. J.

Chromatogr. A 2010, 1217, 633−641.

(36) Wei, H.; Aziz-Schwanbeck, A. C.; Zou, Y.; Corcoran, M. B.;

Poghosyan, A.; Li, A.; Rockne, K. J.; Christensen, E. R.; Sturchio, N. C.

Polybromodiphenyl ethers and decbromodiphenyl ethane in aquatic sediments for Southern and Eastern Arkansas, United States. Environ.

Sci. Technol. 2012, 46, 8017−8024.

(37) La Guardia, M. J.; Hale, R. C.; Harvey, E. Detailed polybrominated diphenyl ether (PBDE) congener composition of the widely used penta-, octa- and deca-PBDE technical flame-retardant mixtures. Environ. Sci. Technol. 2006, 40, 6247−6254.

(38) Stapleton, H. M.; Allen, J. G.; Kelly, S. M.; Konstantinov, A.;

Klosterhaus, S.; Watkins, D.; McClean, M. D.; Webster, T. F. Alternate and new brominated flame retardants detected in U.S. house dust.

Environ. Sci. Technol. 2008, 42 (18), 6910−6916.

(39) VECAP 2011, The Voluntary Emissions Control Action Programme, Annual Progress Report 2010, http://www.vecap.info/ flipbook/vecap-sustainable-2/HTML/index.html (accessed May 3, 2013).

(40) La Guardia, M. J.; Hale, R. C.; Harvey, E. Evidence of debromination of decabromodiphenyl ether (BDE-209) in biota from a wastewater receiving stream. Environ. Sci. Technol. 2007, 41, 6663− 6670.

(41) Stapleton, H. M.; Allen, J. G.; Kelly, S. M.; Konstantinov, A.;

Klosterhaus, S.; Watkins, D.; McClean, M. D.; Webster, T. F. Alternate and new brominated flame retardants detected in U.S. house dust.

Environ. Sci. Technol. 2008, 42, 910−6916.

(42) Köppen, R.; Becker, R.; Jung, C.; Nehls, I. On the thermally induced isomerization of hexabromocyclododecane stereoisomers.

Chemosphere 2008, 71, 656−662.

(43) Kajiwara, N.; Sueoka, M.; Ohiwa, T.; Takigami, H.

Determination of flame-retardant hexabromocyclododecane diaster-eomers in textiles. Chemosphere 2009, 74, 1485−1489.

Environmental Science & Technology Article dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509649 http://ewasteguide.info/node/4166 http://ewasteguide.info/node/4166 http://chm.pops.int/Implementation/NewPOPs/TheNewPOPs/tabid/672/Default.aspx http://chm.pops.int/Implementation/NewPOPs/TheNewPOPs/tabid/672/Default.aspx http://www.epa.gov/oppt/existingchemicals/pubs/actionplans/deccadbe.html http://www.epa.gov/oppt/existingchemicals/pubs/actionplans/deccadbe.html http://www.epa.gov/osw/hazard/international/basel3.htm http://dx.doi.org/10.1016/j.Chemosphere.2013.01.036 http://dx.doi.org/10.1016/j.Chemosphere.2013.01.036 http://www.nedlac.org.za/media/94760/chemicals_impact_assessment_final_consolidated_report_-_2010.pdf http://www.nedlac.org.za/media/94760/chemicals_impact_assessment_final_consolidated_report_-_2010.pdf http://www.klif.no/publikasjoner/2462/ta2462.pdf http://www.klif.no/publikasjoner/2462/ta2462.pdf http://yosemite.epa.gov/opa/admpress.nsf/0/C6BE79994C3FD08785257B3B0054E2FA http://yosemite.epa.gov/opa/admpress.nsf/0/C6BE79994C3FD08785257B3B0054E2FA http://yosemite.epa.gov/opa/admpress.nsf/0/C6BE79994C3FD08785257B3B0054E2FA http://www.vecap.info/flipbook/vecap-sustainable-2/HTML/index.html http://www.vecap.info/flipbook/vecap-sustainable-2/HTML/index.html

(44) Province of KwaZulu-Natal, Dept. Agriculture, Environmental Affairs & Rural Development, Bay of Natal, Estuarine Management Plan, Situation Assessment, March 2012. Chapter 3: Ecological characteristics and estuarine functioning. http://www.erm.com/ bayofdurban (accessed May 3, 2013).

(45) Shaw, S. D.; Kannan, K. Polybrominated diphenyl ethers in marine ecosystems of the American continents: Foresight from current knowledge. Rev. Environ. Health 2009, 24, 157−229.

(46) Klosterhaus, S. L.; Stapleton, H. M.; La Guardia, M. J.; Greig, D.

J. Brominated and chlorinated flame-retardants in San Francisco Bay sediments and wildlife. Environ. Int. 2012, 47, 56−65.

(47) Mai, B.; Chen, S.; Luo, X.; Chen, L.; Yang, Q.; Sheng, G.; Peng, P.; Fu, J.; Zeng, E. Y. Distribution of polybrominated diphenyl ethers in sediments of the Pearl River Dalta and adjacent South China Sea.

Environ. Sci. Technol. 2005, 39, 3521−3527.

Environmental Science & Technology Article dx.doi.org/10.1021/es4020212 | Environ. Sci. Technol. 2013, 47, 9643−96509650 http://www.erm.com/bayofdurban http://www.erm.com/bayofdurban