Environmental Fate and Toxicity of Three Brominated Flame Retardants in Aquatic Mesocosms

451 Pages·2012·7.15 MB·English

Environmental Fate and Toxicity of Three Brominated Flame
Retardants in Aquatic Mesocosms

by
Benjamin P. de Jourdan

A Thesis
Presented to
The University of Guelph

In partial fulfilment of requirements
for the degree of
Doctor of Philosophy
in
Environmental Biology and Toxicology

Guelph, Ontario, Canada

© Benjamin P. de Jourdan, September, 2012
Abstract

ENVIRONMENTAL FATE AND TOXICITY OF THREE BROMINATED FLAME
RETARDANTS IN AQUATIC MESOCOSMS

Benjamin Patrick de Jourdan Advisors:
University of Guelph, 2012 K.R. Solomon
D.C.G. Muir
M.L. Hanson
P.K. Sibley

Tradtional brominated flame retardants (BFRs), namely the polybrominated
diphenyl ethers (PBDEs), have persistent, bioaccumulative, and toxic properties that have
resulted in the phase out of their production and their be banned in certain jurisdictions.
To meet regulatory flame retardancy requirements, non-PBDE BFRs have entered the
marketplace. Much remains unknown regarding the environmental fate and toxicity of
these emerging BFRs. The objective of this thesis was to use outdoor mesocosms to
examine the fate and toxicity of three emerging BFRs; bis(tribromophenoxy)ethane
(BTBPE), tetrabromobisphenol A bis(dibromopropyl ether) (TBBPA-DBPE), and BZ-54,
which consists of two BFRs, ethylhexyl-tetrabromobenzoate (EHTeBB) and
bis(ethylhexyl)tetrabromophthalate (BEHTBP).
While it was difficult to accurately determine degradation rates because of
fluctuating concentrations, the estimated half-lives indicated these compounds are
persistent (> 60 days in sediments). The partitioning of the compounds between the
particulates and the sediment resulted in differential degradation rates (greater in the
particulates), and products formed; those formed on the particulates were consistent with
photodegradation products.
The effects of these emerging BFRs on Hyalella azteca and the benthic
macroinvertebrate community were assessed through the use of in situ exposure and
sampling techniques. The in situ Hyalella cages showed a high degree of variability for
most endpoints, regardless of their placement (e.g., water column vs. sediment) in the
mesocosm. BTBPE accumulated in the H. azteca (0.03 – 1.4 ng/g ww), however this was
not associated with any changes in growth or reproduction. There was high variability in
abundance and diversity between the mesocosms, which limited the ability to detect
statistically significant differences. Interestingly, the BZ-54 treated mesocosms had the
greatest abundance, and the least amount of community diversity.
This thesis examined the bioaccumulation potential of these compounds in
fathead minnow (Pimephales promelas), as well as the associated effects on growth and
development as measured through physical and biochemical endpoints. There was
considerable uptake and persistence of BTBPE and TBBPA-DBPE, as well as indication
of metabolism of these compounds, but limited physical effects observed. There were
indications of increased oxidative stress in the BZ-54 treatment, and increased induction
of vitellogenin in fathead minnow from the BTBPE treatment.
Acknowledgements
Firstly, I would like to acknowledge the mentorship and direction provided by my
advisors Mark Hanson, Paul Sibley, Derek Muir, and Keith Solomon. Your
encouragement and support has made this such an incredible experience. I am incredibly
greatful for the amazing opportunites and experiences over the past 5 years.
I have had the good fortune of collaborating with many great people, particularly
Ken Oakes, Adrienne Bartlett, and Mike White, whose contributions and insights to this
thesis are greatly appreciated. As well as the many people at CCIW who have provided
support and encouragement, Amila, Colin, Jeff, Mary, Camilla, Christine, Lisa, Xiaowa,
and Mark, thank you all.
To all the grad students, past and present - Derek, Rick, Kelly, Jordana, Becca,
Adam, Klaus, Leilan, Dana, Pepe, Ryan, and, Paddy - thank you for being awesome,
inspiring, and great friends. To the visiting students who have passed through Guelph,
Neil, Maj-Britt, and Mitch, your quick visits have had a long lasting impact on me, and I
look forward to crossing paths again.
For the friends who have been supportive throughout this process, Manni, Joe,
Tyler, Ray, Lisa, and Hamish - you all have kept me grounded, focused, and were always
there for a good time. Ellen, your support and understanding throughout this process has
been incredible. I am so grateful that you were there with me during this experience.
And finally, to my family, Em, Dad, and Mom, thank you so much for the love,
support, and incredible generosity. I would not be who I am today without each of you.
iv
Preface

This thesis has been written as a series of manuscripts to be submitted for
publication in scientific journals. Some repetition of introductory and methodological
material is unavoidable. The titles and authorship of these publications are listed below.

Chapter 1 and 2. de Jourdan, B.P., Hanson, M.L., Muir, D.C.G., and Solomon, K.R.
2012. Review of the fate and toxicity of non-PBDE brominated flame retardants:
Modeled estimates and environmental distribution. To be submitted to Reviews of
Environmental Contamination and Toxicology (2012)

Chapter 3. de Jourdan, B.P., Hanson, M.L., Muir, D.C.G., and Solomon, K.R. 2012.
Environmental fate and distribution of 3 non-PBDE brominated flame retardants under
mesocosm conditions. To be submitted to Environmental Toxicology and Chemistry
(2012)

Chapter 4. de Jourdan, B.P. Bartlett, A., White, M., Hanson, M.L., Muir, D.C.G., and
Solomon, K.R. 2012. Ecological effects of 3 non-PBDE brominated flame retardants on
freshwater organisms. To be submitted to Aquatic Toxicology (2012)

Chapter 5. de Jourdan, B.P., Oakes, K., Hanson, M.L., Muir, D.C.G., and Solomon, K.R.
2011. Physiological effects of 3 non-PBDE brominated flame retardants on Pimephales
promelas (fathead minnows) exposed in outdoor mesocosms. Interdisciplinary Studies on
Environmental Chemistry-Environmental Pollution and Ecotoxicology, Eds. M.
Kawaguchi, K. Misaki, H. Sato, T. Yokokawa, T. Itai, T.M. Nguyen, J. Ono and S.
Tanabe, pp 55-66.

Chapter 5. de Jourdan, B.P., Oakes, K., Hanson, M.L., Muir, D.C.G., and Solomon, K.R.
2012. Uptake and biotransformation of 3 non-PBDE brominated flame retardants by
Pimephales promelas (fathead minnows). To be submitted to Aquatic Toxicology (2012)

v
Table of Contents
Abstract ................................................................................................................... ii
Acknowledgements ................................................................................................ iv
Preface ..................................................................................................................... v
Table of Contents ................................................................................................... vi
List of Tables ......................................................................................................... xii
List of Figures ...................................................................................................... xvi
List of Abbreviations .......................................................................................... xxii
1 Literature Review ........................................................................................... 1
1.1 Overview of Thesis ................................................................................................. 1
1.2 Background Information ......................................................................................... 3
1.2.1 Fire and Evolution of Humans ................................................................................. 3
1.2.2 What is Fire? ............................................................................................................ 3
1.2.3 The Destructive Nature of Fire ................................................................................ 5
1.3 Brominated Flame Retardants ................................................................................. 9
1.3.1 Mechanism of Action of Halogenated Flame Retardants ........................................ 9
1.3.2 Use and Sources of Brominated Flame Retardants ................................................ 12
1.3.3 Environmental Occurrence and Processes ............................................................. 18
1.3.4 Pathways of Degradation of BFRs ......................................................................... 24
1.3.5 Toxicity and Bioaccumulation Potential of BFRs ................................................. 29
1.3.6 Regulation of the BFRs .......................................................................................... 49
1.4 Novel Halogenated Flame Retardants ................................................................... 51
1.4.1 Physical and Chemical Properties .......................................................................... 53
1.4.2 Compounds ............................................................................................................ 56
1.4.3 Analytical Methods for Novel HFRs ..................................................................... 61
1.4.4 Environmental Distribution of the Test Compounds ............................................. 74
1.4.5 Toxicity and Potential for Bioaccumulation .......................................................... 76
1.5 Mesocosms ............................................................................................................ 82
1.5.1 Definition ............................................................................................................... 82
1.5.2 Benefits of Mesocosm Studies ............................................................................... 82
1.5.3 Challenges Associated with Mesocosm Studies .................................................... 84
1.5.4 Utility of Mesocosm Studies .................................................................................. 86
vi
1.5.5 Guelph Microcosm Facility ................................................................................... 91
1.6 Summary and Objectives ....................................................................................... 91
1.7 Hypotheses ............................................................................................................ 92
2 In silico Approaches to Modelling the Fate and Toxicity of Non-
Polybrominated Diphenyl Ethers Brominated Flame Retardants .......... 94
2.1 Abstract ................................................................................................................. 94
2.2 Introduction ........................................................................................................... 94
2.3 Methods ................................................................................................................. 97
2.3.1 Compounds ............................................................................................................ 97
2.3.2 Procedure ............................................................................................................... 98
2.3.3 Physical and Chemical Properties .......................................................................... 99
2.3.4 Environmental Partitioning and Persistence ........................................................ 101
2.3.5 Bioconcentration and Bioaccumulation Potential ................................................ 102
2.3.6 Toxicity ................................................................................................................ 106
2.4 Results ................................................................................................................. 110
2.4.1 Physical and Chemical Properties ........................................................................ 110
2.4.2 Environmental Fate .............................................................................................. 113
2.4.3 Bioavailability ...................................................................................................... 116
2.4.4 Toxicity ................................................................................................................ 125
2.4.5 Comparison of Novel and Traditional BFRs ....................................................... 130
2.5 Limitations and Uncertainty ................................................................................ 133
2.6 Discussion ........................................................................................................... 134
3 The Environmental Fate of non-PBDE BFRS in Outdoor Mesocosms 138
3.1 Abstract ............................................................................................................... 138
3.2 Introduction ......................................................................................................... 138
3.3 Materials and Methods ........................................................................................ 142
3.3.1 Chemicals and Materials ...................................................................................... 142
3.3.2 Design of the Study and Treatment of the Mesocosms ........................................ 143
3.3.3 Sampling of Water and Sediment ........................................................................ 145
3.3.4 Extraction of Samples .......................................................................................... 146
3.3.5 Analysis................................................................................................................ 148
3.3.6 Quality Assurance/ Quality Control ..................................................................... 148
3.3.7 Data Analysis and Statistics ................................................................................. 149
vii
3.4 Results ................................................................................................................. 150
3.4.1 Identification of the Test Compounds .................................................................. 150
3.4.2 Method Performance ............................................................................................ 152
3.4.3 Environmental Fate of the BFRs .......................................................................... 153
3.5 Discussion ........................................................................................................... 167
3.6 Conclusions ......................................................................................................... 169
3.7 Acknowledgments ............................................................................................... 169
4 Effects of Non-PBDE BFRs on Common Freshwater Macroinvertebrates
Exposed in Outdoor Mesocosms ............................................................... 170
4.1 Abstract ............................................................................................................... 170
4.2 Introduction ......................................................................................................... 171
4.3 Materials and Methods ........................................................................................ 177
4.3.1 Test Compounds .................................................................................................. 177
4.3.2 Design of the Study and Treatment of the Mesocosms ........................................ 177
4.3.3 Sampling of Water and Sediment ........................................................................ 178
4.3.4 Hyalella Cages and Experimental Design............................................................ 179
4.3.5 Macroinvertebrate Sampling and Identification................................................... 182
4.3.6 Extraction and Chemical Analysis ....................................................................... 183
4.3.7 Data Parameters and Statistical Analysis ............................................................. 185
4.4 Results ................................................................................................................. 189
4.4.1 Physicochemical Parameters ................................................................................ 189
4.4.2 Concentration of BFRs in the Mesocosms ........................................................... 192
4.4.3 BFR Uptake by H. azteca .................................................................................... 192
4.4.4 H. azteca Survival, Growth, and Reproduction ................................................... 193
4.4.5 Comparison of Correlation Analysis Between Exposure Types .......................... 196
4.4.6 Benthic Macroinvertebrate Community Composition ......................................... 198
4.4.7 Diversity and Tolerance ....................................................................................... 200
4.4.8 Principal Component Analysis............................................................................. 202
4.4.9 Statistical Sensitivity ............................................................................................ 205
4.5 Discussion ........................................................................................................... 209
4.6 Conclusions and Considerations for Future Studies ............................................ 217
4.7 Acknowledgments ............................................................................................... 219
viii
5 Exposure of Fathead minnow (Pimephales promelas Rafinesque) to
Three Non-PBDE BFRs in Outdoor Mesocosms; Bioaccumulation,
metabolism, and biochemical effects ........................................................ 220
5.1 Abstract ............................................................................................................... 220
5.2 Introduction ......................................................................................................... 221
5.3 Materials and Methods ........................................................................................ 227
5.3.1 Compounds .......................................................................................................... 227
5.3.2 Experimental Design and Sampling of Water and Sediment ............................... 227
5.3.3 Fish Exposure and Sampling................................................................................ 229
5.3.4 BFR Analysis ....................................................................................................... 230
5.3.5 Biochemical Measures ......................................................................................... 234
5.3.6 Statistics ............................................................................................................... 235
5.4 Results ................................................................................................................. 236
5.4.1 Water Quality Parameters .................................................................................... 236
5.4.2 Fate of the BFRs in the Mesocosms ..................................................................... 238
5.4.3 Accumulation of the BFRs ................................................................................... 239
5.4.4 Growth Responses ............................................................................................... 244
5.4.5 Biochemical Responses........................................................................................ 246
5.5 Discussion ........................................................................................................... 249
5.6 Acknowledgements ............................................................................................. 252
6 General Discussion and Conclusions ........................................................ 253
6.1 Summary of Research Objectives ....................................................................... 253
6.1.1 Produce an analytical procedure for extraction and analysis of non-PBDE BFRs
............................................................................................................................. 254
6.1.2 Determine the fate and behavior of non-PBDE BFRs with respect to degradation
and partitioning between water and sediment ..................................................... 255
6.1.3 Determine the effect of the compounds on the composition of the benthic
macroinvertebrate community ............................................................................. 256
6.1.4 Determine the impacts of the compounds on the growth and survivability of
Hyalella azteca, exposed via the water column and in association with sediments.
............................................................................................................................. 257
6.1.5 Determine the bioavailability and effects of these compounds in fathead minnow
(Pimephales promelas), under semi-natural conditions ...................................... 258
6.1.6 Future Considerations .......................................................................................... 260
6.2 Concluding Statement ......................................................................................... 265
ix
7 References ................................................................................................... 267
8 Appendix ..................................................................................................... 303
8.1 Test Compounds Technical Specifications.......................................................... 303
8.1.1 BTBPE ................................................................................................................. 303
8.1.2 TBBPA-DBPE ..................................................................................................... 303
8.1.3 BEHTBP .............................................................................................................. 304
8.1.4 EHTeBB ............................................................................................................... 304
8.2 in Silico Properties ............................................................................................... 306
8.2.1 Biotransformation ................................................................................................ 306
8.2.2 Biodegradability ................................................................................................... 307
8.2.3 EDKB Database Results ...................................................................................... 308
8.3 Analytical Procedures .......................................................................................... 323
8.3.1 Instrumental Analysis using Gas Chromatography- Mass Spectrometry ............ 323
8.3.2 General Laboratory Preparation Protocols ........................................................... 325
8.3.3 Fathead Minnow Extraction and Processing ........................................................ 331
8.3.4 Sediment Extraction and Processing .................................................................... 335
8.3.5 Water Filters ......................................................................................................... 337
8.3.6 Chromatographs ................................................................................................... 339
8.4 Mesocosms .......................................................................................................... 346
8.4.1 Photos of the Mesocosms ..................................................................................... 348
8.5 Concentrations of the BFRs in the Mesocosms ................................................... 351
8.6 Hyalella azteca and Benthic Macroinvertebrate Studies Supporting Information
353
8.6.1 PCA of 2009 Water Chemistry Data .................................................................... 353
8.6.2 Hyalella ................................................................................................................ 354
8.6.3 Benthic Macroinvertebrate ................................................................................... 359
8.7 Fish Study Supporting Information ..................................................................... 361
8.7.1 Fish Assessment Sheet ......................................................................................... 361
8.7.2 Growth and Physical Responses .......................................................................... 362
8.7.3 Biochemical ......................................................................................................... 364
8.7.4 Uptake and Metabolism ....................................................................................... 368
8.8 Precipitation Data for 2009 ................................................................................. 372
8.9 Additional Studies ............................................................................................... 373
x