Assessment of Polybrominated diphenyl ethers (PBDEs) in freshwater ...

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Lower Tamar River. 6. Upper Derwent. 7. ... 25. Port Jackson West. 26. Parramatta R. A & B. 27. ... Brisbane River (City & Indooroopilly). 35. Luggage Point Up ...
Assessment of Polybrominated diphenyl ethers (PBDEs) in freshwater, estuarine and marine surface sediment associated with various land-uses in Australia Leisa-Maree L. Toms1, Munro Mortimer2, Robert K. Symons3, Olaf Paepke4 and Jochen F. Mueller1 1 National Research Centre for Environmental Toxicology, The University of Queensland, 39 Kessels Road, Coopers Plains, Queensland 4108, Australia 2 Queensland Environmental Protection Agency, 80 Meiers Rd, Indooroopilly, 4068, Australia 3 National Measurement Institute, 1 Suakin St, Pymble 2073, NSW, Australia 4 ERGO/Eurofins, Geierstrasse 1, D-22305, Hamburg, Germany Introduction Polybrominated diphenyl ethers (PBDEs) are incorporated into a variety of manufactured products to reduce flammability. Aquatic sediments provide a final sink for persistent organic pollutants such as PBDEs. This is concerning since PBDEs have the potential to bioaccumulate and biomagnify and food intake has been suggested as one of the major routes of human exposure (Wijesekera et al., 2002) with ingestion of aquatic organisms such as fish and shellfish resulting in the highest intake of PBDEs compared to other food groups (Darnerud et al., 2006, Kiviranta et al., 2004). Prior to the current study, no data were available on PBDE contamination in the Australian aquatic environment. However, after finding unexpectedly elevated PBDE concentrations in human milk and blood sera from Australia with concentrations higher than found in Europe but lower than found in North America (Harden et al., 2004, Harden et al., 2005) it was decided to investigate PBDEs in the Australian environment. This study aimed to obtain background data on PBDE concentrations and congener profiles in sediment from samples representing various Australian locations. The sampling plan was designed to allow assessment of PBDE concentrations by salinity and land-use type. Materials and Methods Surface sediment was obtained at 46 sampling sites from 39 locations across all eight States and Territories of Australia (Figure 1). These sites were chosen to be representative of various land-uses – remote (5), remote/agricultural (2), agricultural (7), urban (11), urban/industrial (9), industrial/urban/agricultural (1), industrial (7) and proximity to sewerage treatment plant outfalls (STPs) (4). In addition, the sites were differentiated according to salinity with 20 sites from freshwater, 25 from estuarine waters and one from marine waters. The majority of samples were collected in 2002/03 with six additional samples collected in 2005. All samples were stored in glass jars or sealed aluminium foil packets in dry, dark conditions between collection, processing and analysis. For all sample collections, detailed sampling procedures were implemented to avoid sample contamination (see Mueller et al. 2004). The sediment samples were freeze dried and sieved. The < 2 mm fraction was analysed at the National Measurement Institute (NMI), Sydney, Australia using isotope dilution methods on a HRGC-HRMS where the following congeners were quantified: BDEs- 17, -28, -33, -47, -49, -66, -71, -77, -85, -99, -100, -119, -126, -138, -153, -154, -156, -166, -183, -184, -191, -196, 197, 206, 207 and -209 (for details see Toms et al. 2006). This study provided two phases of quality control/ quality assurance including sampling reproducibility and inter-laboratory comparison with selected duplicate samples sent to ERGO/Eurofins in Hamburg, Germany. The results of both were deemed acceptable.

20

21

NT QLD WA 363234 31 33 35

SA 16 17 15 19 18

NSW

28 29 262524 27

21 43

22 23

VIC 11 14 13 9

12 10

TAS 67 8

30

1. Upper Torrens 2. Torrens River A & B 3. Lower Torrens 4. Torrens Estuary 5. Lower Tamar River 6. Upper Derwent 7. Hobart Derwent R 8. Lower Derwent A & B 9. LaTrobe R Industrial 10. LaTrobe R Agricultural 11. Upper Yarra 12. Port Phillip Bay 13. Port Phillip Bay A & B (Lower Yarra A & B) 14. Lower Werribee 15. Upper Avon 16. Middle Swan A& B 17. Upper Swan 18. Upper Serpentine 19. Canning R. 20. Port of Darwin 21. Kakadu 22. Canberra Lake Burley Griffin A & B 23. ACT Up and downstream STP 24. Port Jackson East 25. Port Jackson West 26. Parramatta R. A & B 27. Botany Bay 28. Lower Hunter 29. East of Newcastle 30. Lake Illawarra 31. Moreton Bay 32. Upper Bris 33. Lower Bris A & B 34. Brisbane River (City & Indooroopilly) 35. Luggage Point Up & downstream STP 36. Bremer R. Up & downstream STP

States and Territories: SA – South Australia; Tas – Tasmania; Vic – Victoria; WA – Western Australia; NT – Northern Territory; ACT – Australian Capital Territory; NSW – New South Wales; QLD – Queensland

Figure 1. Map of sampling locations Results and discussion PBDEs were detected at 35 of 46 sites with the overall ΣPBDE concentrations (sum of all congeners determined) ranging from non detect to 60900 pg.g-1 dry weight (dw) with the mean ± standard deviation and median ΣPBDE concentrations across all sites 4707 ± 12580 and 305 pg.g-1 dw, respectively excluding the limit of detection. Overall the concentrations were low and at 83% of sites the level of contamination was non-detectable or less than 1000 pg.g-1 dw. When assessed by salinity, ΣPBDE concentrations differed significantly between estuarine and fresh waters (p=0.02, Kruskal-Wallis test) with the ΣPBDE concentrations approximately 10 times higher in samples collected in estuarine waters compared to fresh water (Table 1). No PBDEs were detected at the one marine water site. The higher concentrations of PBDEs in estuaries are consistent with the proximity to potential diffuse urban inputs and point sources such as industry or STPs that are mostly situated close to Australia’s estuaries. In contrast, the freshwater sites in this study were typically inland which in Australia means mostly distant from the major metropolitan and industrial centres.

Table 1. ΣPBDE results by salinity (pg.g-1 dw excluding LOD). Salinity Freshwater Estuarine Marine

Number of samples 20

Mean 720 (890)

Standard deviation 1740 (1710)

Median 100 (320)

25 1

8090 (8200) n/a

16400 (16300) n/a

1060 (1140) n/a

Range nd – 7730 (40-7750) nd – 60900 (9660940) Nd

Results including the LOD are included in parenthesis. Where a result was non-detect it was considered to be zero for summary results. All results are reported to two to three significant figures. n/a = not assessable nd = non-detected

When assessed by land-use type ΣPBDE concentrations also differed significantly (p=0.007, KruskalWallis test) with generally greater concentrations in samples collected from industrial/urban, industrial, STP outfalls and urban locations while the lowest concentrations were from the remote, agricultural, remote/agricultural and industrial/urban/agricultural areas (Table 2). Table 2. ΣPBDE results by land-use type (pg.g-1 dw excluding LOD). Number of samples

Mean

Standard Deviation

Median

Range

Remote

5

96 (230)

210 (210)

n/a (170)

nd-480 (40-590)

Remote/ agricultural

2

47 (220)

14 (35)

n/a (220)

37-57 (200-250)

Agricultural

7

52 (230)

96 (110)

2 (230)

nd-250 (96-420)

Agricultural/ urban/ industrial

1

n/a

n/a

n/a

33 (120)

Urban

11

880 (1100)

910 (880)

530 (740)

nd-2800 (240-2800)

STPs

4

3400 (3500)

3400 (3300)

2700 (2800)

380-7700 (590-7800)

Industrial

7

3900 (4000)

9100 (9100)

170 (340)

nd-25000 (210-25000)

Industrial/ urban

9

17000 (18000)

23000 (23000)

1700 (2200)

nd-61000 (170-61000)

Results across all samples 46 4700 (4900) 13000 (13000) 310 (480) nd-61000 (40-61000) Results including the LOD are included in parenthesis. Where a result was non-detect it was considered to be zero for summary results. All results are reported to two to three significant figures. n/a = not assessable nd = non-detected

Sediment samples obtained from sites up- and downstream near the outfall of STPs showed ΣPBDE concentrations were higher at sites down- relative to upstream. While the outfall from STPs may be a potential point source of PBDEs into the aquatic environment, other land-use types (i.e. industrial/urban, urban and industrial) have higher or similar levels of contamination indicating that sources other than STPs are similarly and/or more relevant as PBDE sources to aquatic environments in Australia. In 30 out of 35 samples where PBDEs were detected, BDE-209 made the greatest contribution to the ΣPBDE concentration, ranging from 43 to 100%. However, one sample (Port Phillip Bay, Vic) had a profile dominated by BDE-183 suggesting there is a point source of the octa-BDE commercial product for which BDE-183 is a marker in the vicinity of this site. The concentration of 31000 pg.g-1 dw BDE -183 from Port Phillip Bay is to the authors’ knowledge, the highest reported for this congener in a sediment sample. For all sites, the mean (median) concentrations of BDEs -47, -99, -100, -153, -154, -183 and -209 were 645 (350), 509 (300), 136 (79), 168 (30), 55 (28), 1526 (15) and 4153 (880) pg.g-1 dw, respectively. .

The median ΣPBDE (305 pg.g-1 dw) and BDE-209 (880 pg.g-1 dw) concentrations are low or similar to results from countries in North America, Europe and Asia (Oros et al., 2005, Mai et al., 2005, Eljarrat et al., 2005). Although the majority of locations sampled in this study had non-detectable or low PBDE concentrations there were a small number of locations with unexplained high contamination which may suggest unidentified point sources to the aquatic environment. As the usage pattern of the commercial BFR products change over time, the results of this study will be able to be used as baseline data for future monitoring to assess whether concentrations of PBDEs change in the aquatic environment. Acknowledgements The authors like to thank the environmental professionals who assisted with sample collection and the staff of the NMI Dioxins Analysis Unit and Eurofins/ ERGO. EnTox is co-funded by Queensland Health. This work was funded in part by a grant from the Australian Government Department of Environment and Heritage. The views expressed in this publication do not necessarily reflect those of the Australian Government or the Minister for the Department of Environment and Heritage. References Darnerud, P. O., Atuma, S., Aune, M., Bjerselius, R., Glynn, A., Petersson Grawe, K. and Becker, W. 2006. Food and Chemistry Toxicology. 44(9):1597-606 Eljarrat, E., de la Cal, A., Lazzazabal, D., Fabrellas, B., Fernandez-Alba, A. R., Borrull, F., Marce, R. M. and Barcelo, D. 2005. Environmental Pollution, 136, 493-501. Harden, F. A., Toms, L.-M. L., Ryan, J. J. and Mueller, J. F. 2004. In: Proceedings of the Third International Workshop on Brominated Flame Retardants, June 6-9 2004, Toronto, Canada, 59-62. Harden, F. A., Mueller, J. F. and Toms, L.-M. 2005 Environment Protection and Heritage Council of Australia and New Zealand., pp. 91. Hyötyläinen, T. and Hartonen 2002. Trends in Analytical Chemistry, 21, 13-39. Kiviranta, H., Ovaskainen, M.-L. and Vartiainen, T. 2004. Environment International, 30, 923-932. Mai, B., Shejun, C., Luo, X., Chen, L., Yang, Q., Sheng, G., Peng, P., Fu, J. and Zeng, E. Y. 2005. Environ Sci Technol, 39, 3521-3527. Mueller, J. F., Muller, R., Goudkamp, K., Mortimer, M., Haynes, D., Paxman, C., Hyne, R., McTaggart, A., Burniston, D., Symons, R. K. and Moore, M. 2004 Australian Govt Dept Env & Heritage, Canberra. Oros, D. R., Hoover, D., Rodigari, F., Crane, D. and Sericano, J. 2005. Environ Sci & Tech, 39, 33-41. Toms, L., Mueller, J., Mortimer, M., Symons, R., Stevenson, G. and Gaus, C. 2006 Australian Govt Dept Env & Heritage, Canberra Wijesekera, R., Halliwell, C., Hunter, S. and Harrad, S. 2002. Organohalogen Compounds, 55, 239-242.