Environmental Toxicology and Chemistry, Vol. 29, No. 5, pp. 1031–1035, 2010# 2010 SETAC

Printed in the USADOI: 10.1002/etc.137

HUMAN EXPOSURE TO POLYBROMINATED DIPHENYL ETHERS

AT PRODUCTION AREA, CHINA

JUN JIN,*y YING WANG,y CONGQIAO YANG,y JICHENG HU,y WEIZHI LIU,z and JIAN CUIzyCollege of Life and Environmental Sciences, Central University for Nationalities, 100081, Beijing, People’s Republic of China

zChinese Minority Tradition Medicine Center, Central University for Nationalities, 100081, Beijing, People’s Republic of China

(Submitted 6 March 2009; Returned for Revision 7 June 2009; Accepted 8 December 2009)

* T(junjin

Pub(www.

Abstract—The concentrations of polybrominated diphenyl ethers (PBDEs) were detected in air and aquatic products in PBDEsproduction areas which are located at the south coast area of Laizhou Bay, Shandong province, China in this study. Concentrations ofP

PBDEs in the air ranged from 0.47 ng/m3 to 161 ng/m3. In aquatic products, concentrations ofP

PBDEs ranged from 2.7 ng/g wetweight to 42 ng/g wet weight. The mean dietary intake of

PPBDEs via aquatic products consumption in this study was 218 ng/day. Daily

intake ofP

PBDEs via inhalation in this study was 612 ng for men and 455 ng for women. With a contribution of 80%, BDE-209 waspredominant in the total intake. Dietary intake and breathing inhalation contributed 29 and 71%, respectively, to the total PBDEs intake.The results indicate that breathing inhalation also plays a very significant pathway for the population of the PBDEs production area.Compared with similar studies in other countries, human exposure to PBDEs via diet and inhalation in this study was the highest in theworld. Environ. Toxicol. Chem. 2010;29:1031–1035. # 2010 SETAC

Keywords—Polybrominated diphenyl ethers Exposure Dietary intake Inhalation Production area

INTRODUCTION

Polybrominated diphenyl ethers (PBDEs) have been foundto be ubiquitous in both the living and nonliving parts of theenvironment [1,2]. Levels of PBDEs in biotic and abioticenvironmental compartments have implications for humanexposure. Given the lipophilicity of PBDEs and their presencein consumer products and house dust, suspected routes ofhuman exposure include dietary intake, inhalation, and occupa-tional exposure; the most important factor varies both geo-graphically and among different individuals within a population[3]. Dietary exposure is a significant route of human uptake andis largely attributed to consumption of meat, fish, and dairyproducts, with fish generally having the highest PBDE levels[4,5]. However, dietary intake cannot alone account for thebody burdens measured in the United States [4,6]. Inhalation ofPBDEs from dust and indoor air has been recently identified as apotentially significant source of PBDEs [6]. The indoor envi-ronment and diet both play prominent roles in adult humanexposure to PBDEs [7].

Because high concentrations of PBDEs have been detectedin air, soil, and sediment in PBDEs production areas, which arelocated at the south coast area of Laizhou Bay, Shandongprovince, China [8,9], high environmental pollution must leadto the local residents’ exposure to PBDEs. Therefore, theprimary objectives of the present study were to characterizePBDEs levels in aquatic products, and to estimate dietary intakeand breathing inhalation of PBDEs on a production area scale,at the south coast area of Laizhou Bay, China.

o whom correspondence may be addressed3799@yahoo.com.cn).lished online 1 February 2010 in Wiley InterScienceinterscience.wiley.com).

1031

MATERIALS AND METHODS

Materials and sample collection

Brominated diphenyl ether (BDE)-28, -47, -99, -100, -153, -154, -183, -206, -207, -208, -209, 13C12-BDE 209, 13C12-BDE139, and 13C12-polychlorinated biphenyls (PCBs) 138 wereobtained from Cambridge Isotope Laboratories. All organicsolvents and water were of high-performance liquid chroma-tography-grade or pesticide-grade from Tedia, and used asreceived. All other chemicals were of analytical grade. Heliumgas (99.999%) and methane gas (99.999%) were obtained fromHaiPu.

All aquatic products were purchased from the local marketsof the production areas at the south coast of Laizhou Bay in May2006. They were mainly from local fisheries. They consisted ofsix different seashells (Mactra chinensis, Ruditapes philippi-narum, Barbatia amygdalumtostum, Neverita didyma, Sinono-vacula constricta, and trumpet shell), two kinds of shrimp(Penaeus chinensis, Metapenaeus ensis), and three kinds offish (Acanthogobius flavimanus, Pampus argenteus, Cololabissaira Brevoort). After the samples were collected, they werepackaged with foil, sealed, and then frozen at �188C untilanalysis.

Air samples were taken at six sites surrounding the PBDEsproduction area located at the south coast area of Laizhou Bay.Air samples were taken at six sites: the Tianyi site (378070

31.300N, 119800051.300E), the Houzheng site (36858045.500N,118857032.800E), the Tianliu site (36859040.400N, 1188470

08.500E), the Yangkou site (37815056.500N, 118851033.200E),the Yangzi site (37802051.700N, 119809014.800E), and the Gong-hui site (37807030.800N, 118858052.700E). Air samples werecollected using a modified high volume sampler (Tisch Envi-ronmental). Two separate sampling campaigns were undertakenin the winter and summer, the first on January 22–31, 2007 andthe second on July 18–29, 2007. During these periods, 46

1032 Environ. Toxicol. Chem. 29, 2010 J. Jin et al.

samples including gaseous phase and particulate phase sampleswere taken at sampling sites.

Laboratory analyses

At the laboratory, the aquatic products were shucked using astainless steel knife into appropriate precleaned homogenizingcontainers. The muscle without fish skin was then homogenizedusing a homogenizer. Then, 10 g of aquatic product musclesamples (wet weight) was taken and mixed with Na2SO4 toremove water. The samples were transferred to a pre-extractedglass thimble and spiked with internal standards containing13C12-BDE 139 and 13C12-BDE 209. The aquatic productssamples and air samples were extracted for 24 h and for 48 h,respectively, using 300 ml acetone/hexane (1:3 v/v). The lipidcontent of aquatic products was measured gravimetrically. Theextract was then further cleaned with one multilayer silicacolumns (15 mm inside diameter) filled from the bottom with1 g of activated silica, 4 g of silica/NaOH (KOH for aquaticsamples), 1 g of activated silica, 8 g of silica/H2SO4 44% (w/w),and 2 g of silica topped with 4 g of Na2SO4. The sample waseluted with 20 ml hexane and 100 ml hexane/methylene chlor-ide (1:1), the first fraction was discarded, and the followingfraction was collected in an amber vial, then reduced in volumeto 100ml for analysis. The samples were analyzed for PBDEs bygas chromatograph–mass spectrometer (GC-MS).

Just prior to analysis, an aliquot (2ml� 5mg/ml) of injectionstandard solution containing 13C12-PCB 138 was added to theauto sampler vial. The PBDEs congeners were detected by GC-MS on an Agilent 5975N mass spectrometer equipped with a6890 gas chromatograph (Agilent USA). The analytical columnwas a 30 m length� 0.25 mm internal diameter DB-5 MScapillary column with a 0.10mm film thickness (J & W Sci-entific). The column temperature was initiated at 1008C (heldfor 2 min) and increased to 3008C at 48C/min (held for 25 min).Injector and interface temperatures were 2808C and 3208C,respectively. The carrier gas was helium at a flow rate of 1.0 ml/min. A 1ml splitless injection was then analyzed by GC/MSoperated with a negative chemical ionization source in selectedion monitoring mode. Methane was used as the chemicalionization gas.

One procedural blank and one spiked recovery samplecontaining PBDEs were run with every batch sample. ThePBDE levels in the blank samples were low enough so thatwe did not correct the concentration in the samples. The limit ofdetection of the method (LOD) was defined as the mean blankmass plus three standard deviations. Method detection limitsfor individual BDEs varied from sample to sample and from

Table 1. Concentrations of polybrominated diphenyl eth

Aquatic product BDE-28 BDE-47 BDE-100 BDE-99 BDE-154 B

Metapenaeus ensis 0.07 0.06 0.06 0.07 0.07Penaeus chinensis 0.06 0.05 0.06 0.11 0.07Acanthogobius flavimanus 0.47 0.46 0.08 0.11 0.12Flounder 0.07 0.11 0.07 0.08 0.08Cololabis saira Brevoort 0.51 0.47 0.24 NDa 0.09Trumpet shell 0.10 0.10 0.06 0.07 0.07Mactra chinensis 0.57 1.1 ND ND NDRuditapes philippinarum 2.4 5.2 ND ND NDSmall Neverita didyma 1.1 0.95 ND ND NDBarbatia amygdalumtostum 16 19 ND ND NDLarge Neverita didyma 0.27 1.2 ND ND NDSinonovacula constricta 1.4 1.3 0.07 0.17 0.14Average 2.0 2.5 0.05 0.05 0.05

a ND¼ not determined.

congener to congener, depending on sample size and instrumentsensitivity. The LOD ranged from 1 to 5 pg/g wet weight (tri-tonona-BDEs) to 100 pg/g wet weight (BDE-209) for aquaticproduct, from 0.02 to 0.2 pg/m (tri-to nona-BDEs) to 3.3 pg/m3

(BDE-209) for air samples, respectively.

RESULTS AND DISCUSSION

Estimated PBDEs daily dietary intake

The concentrations of PBDEs in aquatic products are sum-marized in Table 1. The level of PBDEs in Trumpet shell wasthe lowest, which is 2.7 ng/g. Barbatia amygdalumtostum hasthe highest PBDEs concentrations of 42 ng/g. Decabromodi-phenyl ether (BDE-209) was the dominant congener in allsamples except Barbatia amygdalumtostum, BDE-28, BDE-47 was the dominant congener in Barbatia amygdalumtostum.The average concentrations of BDE-28, BDE-47, BDE-100,BDE-99, BDE-154, BDE-153, BDE-183, BDE-208, BDE-207,BDE-206, BDE-209,

PPBDEs were 2.0, 2.5, 0.05, 0.05, 0.05,

0.07, 0.05, 0.26, 0.62, 0.64, 3.4, 9.7 ng/g, respectively. Themajor PBDEs congener was BDE-209, accounting for 35.6% ofthe total concentration. The contribution of BDE-28, BDE-47 tothe total was 20.2 and 25.5%, respectively.

Dietary exposure is a significant route of human uptake andis largely attributed to consumption of meat, fish, and dairyproducts. Estimated daily dietary intake of PBDEs via aquaticproducts consumption was calculated by multiplying the PBDEconcentrations in aquatic products and the amount of fishconsumption from the survey. With increasing income, thedietary components of rural population in Shandong provincehave changed. Great variance exists in the types and quantity ofanimal products used in common recipes since 1978. Forexample, the rural population in Shandong consumed 7.6 kgmeat per capita in 2007, an increase of 1.4 times that in 1978;eggs 10.2 kg, an increase of 10.3 times; 7.4 kg fresh milk, anincrease of 73 times; 4.7 kg aquatic products, an increase by 4.9times (data from the National Bureau of Statistics, ShandongSurvey Organization). In this study, because most of the localresidents at the south coast area of Laizhou Bay in Shandongprovince had been fishermen, the exposure risk to persistentorganic pollutants (POPs) of the local residents through dietshould be higher than other area residents. In 2007, the quantityof consumption of aquatic products per capita in Shandongprovince was 12.9 g/day. This consumption quantity of aquaticproducts per capita in Shandong province was used to calculatethe human intake of PBDEs. As a result, the PBDEs intake forlocal residents in this study may be underestimated.

ers (PBDEs) in aquatic production (ng/g wet wt)

DE-153 BDE-183 BDE-208 BDE-207 BDE-206 BDE-209P

PBDEs

0.09 0.09 0.17 0.19 0.37 3.2 4.40.09 0.09 0.17 0.24 0.33 1.9 3.10.14 0.09 0.16 0.66 0.23 1.6 4.10.09 0.09 0.15 0.69 0.22 1.2 2.90.11 0.09 0.17 0.37 0.29 4.1 6.50.08 0.09 0.15 0.72 0.2 1.0 2.7ND ND 0.47 0.79 1.1 4.2 8.2ND ND 0.38 0.77 1.2 7.4 17ND ND 0.33 0.70 1.1 4.3 8.5ND ND 0.39 0.83 1.1 4.5 42ND ND 0.40 0.78 1.2 4.0 7.90.19 0.12 0.18 0.67 0.26 3.9 8.40.07 0.05 0.26 0.62 0.64 3.4 9.7

Human exposure to PBDEs at production area, China Environ. Toxicol. Chem. 29, 2010 1033

Several previous studies suggested that intake of PBDEs viafish consumption was dominant in the overall intake throughdiet, as 47% of the total PBDEs intake from diet was attributedto fish consumption in Sweden, 30% in Spain, 38% in TheNetherlands, 39% in Belgium, and 52% in Finland [10]. Menget al. [10] considered that 20 to 60% of the total dietary PBDEintake in China originated from fish. Shen et al. [11] prelimi-narily estimated the human PBDEs intake via agriculturalproducts consumption in Hangzhou City, Zhejiang provinceof China. The contributions of aquatic products, poultry, meat,plant food, and egg to the total daily PBDEs intake were 57, 20,20, 2, and 1%, respectively. In this study, 0.57 was regarded asthe contribution ratio of aquatic products to the total PBDEsdietary intake. Therefore, the mean dietary intake of BDE-28,BDE-47, BDE-100, BDE-99, BDE-154, BDE-153, BDE-183,BDE-208, BDE-207, BDE-206, BDE-209,

PPBDEs in this

study were 44, 56, 1.1, 1.1, 1.1, 1.6, 1.1, 5.9, 14, 14, 78, and218 ng/day, respectively. The PBDEs dietary intake valueestimated in this study was more than that reported in theUnited Kingdom (91 ng/day) [12], the United States (88 ng/day) [4], Spain (82 ng/day) [13], Japan (68 ng/day) [14], Finland(43 ng/day) [15], Belgium (23 ng/day) [5], and The Netherlands(13 ng/day) [16].

Estimated PBDEs daily inhalation

In 2007, we measured PBDEs in air samples taken in thewinter and summer at the PBDEs production site and the otherfive sites at the south coast area of Laizhou Bay in China. Theconcentrations of

PPBDEs in gaseous, particulate samples

were in the following ranges: 0.017 to 1.2 ng/m3, 0.35 to161 ng/m3, respectively. The concentrations of PBDEs conge-ners in the air are shown in Table 2.

Dietary intake alone, however, cannot account for the bodyburdens measured in the United States [4,6]. Inhalation ofPBDEs has been identified recently as a potentially significantsource of PBDEs. Therefore, human exposure to PBDEs viainhalation was estimated in this study. The average daily dose(ADD) via inhalation can be estimated by the general equation

ADD ¼ ½C � IR � ED=½BW � ATf gwhere ADD is average daily dose (mg/kg � day), C iscontaminant concentration in inhaled air (ng/m3), IR is theinhalation rate frequency of inbreath (m3/day), ED is exposureduration (day), BW is body weight (kg), and AT is the averagingtime for noncarcinogenic effects AT¼ED (day).

The meanP

PBDEs concentration in inhaled air includinggaseous and particulate phase in this study was 40.3 ng/m3.The daily mean inhalation rates for long-term exposure for

Table 2. Polybrominated diphenyl ether (PBDE) concentrat

AirSamplingseasons BDE-28 BDE-47 BDE-100 BDE-99 BDE-154 B

Particulate Summer Min 0.005 0.004 0.002 0.004 0.003phase Max 0.007 0.008 0.003 0.010 0.006

Mean 0.006 0.006 0.003 0.006 0.004Winter Min 0.003 0.003 0.003 0.003 0.003

Max 0.17 0.15 0.007 0.043 0.029Mean 0.029 0.027 0.004 0.011 0.008

Gaseous Summer Min 0.020 0.010 0.001 0.004 0.004phase Max 0.28 0.18 0.031 0.18 0.016

Mean 0.100 0.045 0.007 0.032 0.008Winter Min 0.003 0.001 0.002 0.001 0.003

Max 0.093 0.004 0.004 0.011 0.007Mean 0.020 0.002 0.003 0.004 0.005

adults were 11.3 m3/day for women and 15.2 m3/day for men, asproposed by the U.S. Environmental Protection Agency [17].According to the equation, the daily intake of

PPBDEs via

inhalation in this study was 612 ng for men and 455 ng forwomen. The mean

PPBDEs exposure via inhalation in this

study was 534 ng. The daily intake of PBDEs congeners viainhalation are shown in Table 3. The maximum daily

PPBDEs

inhalation for men and women were 2,453 ng and 1,824 ng,respectively. Decabromodiphenyl ether-209 was the dominantcongener of the total inhalation, accounting for 91.4% of thetotal. However, the contribution of BDE-28 to the total dailyPBDEs inhalation was only 0.18%. Obviously, human exposureto PBDEs via inhalation is rather complicated and is affected bymany factors, such as gas-particle partitioning, exposure dura-tion, and particulate matter size; therefore, the present studyshould be regarded as a preliminary estimation of humanexposure to PBDEs via inhalation. Meng et al. [10] examinedhuman exposure to PBDEs associated with fish consumptionand inhalation in Guangdong province, China. The mediandaily

PPBDEs inhalation was 2.7 to 9.2 ng, ranging from

0.72 to 108 ng. Wilford et al. [18] collected air samples ran-domly in 74 selected homes and seven outdoor sites in Ottawa,Canada, and estimated the human exposure to PBDEs viainhalation, with median values of 2.0 ng/day and 1.9 ng/dayfor male and female, respectively. Harrad et al. [12] collectedair samples from a range of office and home indoor micro-environments in the United Kingdom, and obtained a medianhuman intake of PBDEs of 6.9 ng/day. Clearly, the daily PBDEsinhalation in this study was greater than those in Canada and theUnited Kingdom, which was attributed to the high concentra-tion of PBDEs in the air at the PBDEs production area.

Assessment of human exposure to PBDEs

The meanP

PBDEs exposure via dietary intake and inha-lation in this study was 752 ng/day, BDE-209 accounting for80%. The contributions of dietary intake and breathing inha-lation to the total PBDEs intake were 29 and 71%, respectively.This result indicated that breathing inhalation played a verysignificant route for the PBDEs exposure to the general pop-ulation of the PBDEs production area in this study. Severalstudies reported that inhalation of PBDEs from household airand dust had been identified as a potentially significant source ofPBDEs [6,19]. The levels of PBDEs in indoor air were usuallymuch higher than that of outdoor air [20], and indoor air mayserve as a major source. In this study, we found the concen-trations of PBDEs in outdoor air at PBDEs production areaswere higher than those of indoor air in U.S. urban residences

ions in the air at the PBDEs production area (ng/m3)

DE-153 BDE-183 BDE-208 BDE-207 BDE-206 BDE-209P

PBDEs

0.003 0.010 0.007 0.014 0.013 0.28 0.350.041 0.056 0.35 0.60 2.8 130 1300.013 0.021 0.12 0.21 0.84 38 390.005 0.006 0.021 0.037 0.030 0.42 0.570.34 0.16 6.30 12 21 120 1600.053 0.041 0.75 1.4 2.2 36 410.004 0.004 0.005 0.008 0.006 0.040 0.120.014 0.007 0.008 0.013 0.014 0.66 1.20.008 0.006 0.006 0.010 0.009 0.16 0.380.005 0.005 0.009 0.011 0.013 0.091 0.0170.012 0.009 0.012 0.051 0.027 0.84 0.950.007 0.006 0.010 0.031 0.020 0.19 0.19

Table 3. Daily polybrominated diphenyl ethers (PBDEs) inhalation formen and women from the PBDEs production area

Congener

PBDEs inhalationfor men (ng/day)

PBDEs inhalationfor women (ng/day)

Mean Max Min Mean Max Min

BDE-28 1.0 4.4 0.09 0.77 3.3 0.07BDE-47 0.55 2.9 0.06 0.41 2.1 0.05BDE-100 0.10 0.52 0.03 0.07 0.38 0.02BDE-99 0.35 2.8 0.05 0.26 2.1 0.03BDE-154 0.18 0.52 0.09 0.14 0.38 0.07BDE-153 0.70 5.3 0.12 0.52 3.9 0.09BDE-183 0.59 2.5 0.09 0.44 1.9 0.07BDE-208 8.2 96 0.18 6.1 71 0.14BDE-207 15 177 0.35 11 132 0.26BDE-206 27 311 0.29 20 231 0.21BDE-209 559 1,918 4.9 416 1,426 3.6P

PBDEs 612 2,453 7.0 455 1,824 5.2

1034 Environ. Toxicol. Chem. 29, 2010 J. Jin et al.

[21]. Therefore, we did not consider the difference of PBDEsconcentration in indoor and outdoor air at the production area.In this study, we consider the outdoor air at the PBDEsproduction area an important role player in human exposure.This result is of high interest for comparison of PCBs exposurein the U.S. general population, of which 95% is estimated tocome from food intake [3]. Additionally, the pattern of intake ofPBDEs from diet was different from inhalation in this study.Figure 1 revealed the contributions of diet and inhalation to thespecific PBDEs congener intake. Clearly, higher brominatedcongeners intake was mainly obtained via inhalation, however,intake of the less brominated congeners mainly originated fromdiet. For example, more than 90% intake of BDE-28, BDE-47,and BDE-100 originated from diet, whereas approximately 86%of BDE-209 originated from inhalation. The preliminary esti-mated PBDEs intake of 752 ng/day equals 11 ng kg/day for aperson weighing 70 kg. This value was higher than that reportedin Guangzhou, China (215–376 pg/kg � day) [10], in the UnitedStates (0.9–1.2 ng/kg � day) [4], Spain (1.2–1.4 ng/kg � day) [13],and Sweden (0.58–0.63 ng/kg � day) [22]. To our knowledge, thepreliminary estimated PBDEs intake at the production area inthis study is the highest in the world. High levels of PBDEs inbiotic and abiotic environmental compartments at the PBDEsproduction area resulted in the high exposure of the localresidents [8,9]. Comparison of the estimated intake of 11 ng/kg � day with the lowest-observable, adverse-effect level value

Fig. 1. The contributions of diet and inhalation pathway to the specificpolybrominated diphenyl ethers (PBDEs) congener intake. &, inhalation;&, dietary intake.

of 1 mg/kg � day results in a safety factor of >105 with regardto the mean PBDE exposure [23]. However, the results raiseconcern regarding the levels of PBDEs in the local residents.The levels of PBDEs in the local population and possible healthrisk will be further studied.

CONCLUSION

The contributions of dietary intake and breathing inhalationto the total PBDEs intake were 29 and 71%, respectively. Thisresult indicates that breathing inhalation is a very significantpathway for the residents at the PBDEs production area. Com-pared with similar studies in non-PBDEs product area, humanexposure to PBDEs via diet and inhalation in this study was thehighest in the world. The current exposure pathway at thePBDEs production area was slightly different from non-PBDEsproduction areas. Manufacturers of PBDEs need to adopt somemeasures to minimize the PBDE emissions. Furthermore,effective measures should be immediately taken to decreasehuman exposures. Further research on exposure levels ofPBDEs and the health impact of PBDEs for the residents inPBDEs production areas is of importance.

Acknowledgement—This work was funded by the National Natural ScienceFunds of China (20507023) and the 985 project of Central University forNationalities.

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