Fate and Effects of an Alkylamine Ethoxylate Surfactant Mixture in Aquatic Systems

303 Pages·2015·6.34 MB·English

by  Jose L. Rodriguez

Fate and Effects of an Alkylamine Ethoxylate Surfactant Mixture
in Aquatic Systems: Pulsed Exposures, Recovery Capacity and the
Importance of Sediment
by
José Luis Rodríguez Gil
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
© José Luis Rodríguez Gil, July, 2015
ABSTRACT
FATE AND EFFECTS OF AN ALKYLAMINE ETHOXYLATE SUR-
FACTANT MIXTURE IN AQUATIC SYSTEMS: PULSED EXPOSURES,
RECOVERY CAPACITY AND THE IMPORTANCE OF SEDIMENT
José Luis Rodríguez Gil Co-Advisors:
University of Guelph, Dr. Keith R. Solomon
2015 Dr. Mark L. Hanson
Dr. Paul K. Sibley
Alkylamine ethoxylates (ANEOs), such as polyoxyethylene(15)tallow amine (POEA) are com-
monly used adjuvants in glyphosate herbicide formulations, such as Roundup® and Vision®. The
available data on the toxicological effects of glyphosate formulations and POEA to aquatic organ-
isms points to the surfactant as the main driver of toxicity from these formulations and suggest
the potential for effects at concentrations close to those estimated to occur in the environment.
Tier-1 environmental hazard assessments based on these observations resulted in regulatory au-
thorities prohibiting direct over-water application of formulations containing POEA in several
countries; still, unintended exposure of aquatic ecosystems to these formulations is possible via
spray drift or, particularly in forestry scenarios, via aerial over-spray of small, shallow wetlands.
The general goal of this thesis was to refine the risk assessments for a commercial mixture of
POEA known as MON 0818 and, by extrapolation, the glyphosate-based herbicide formulations
in which they are present. The refinement goal involved developing a better quantitative under-
standing of the fate of POEAs in aquatic systems with particular emphasis on sorption to sedi-
ment and how the fate of POEAs may influence observed toxicity to non-target aquatic organ-
isms.
The general conclusion from the work presented in this dissertation is that, under real-world envi-
ronmental conditions, unintended exposure of aquatic systems to POEA surfactants will most
likely result in short, single-pulse, exposures. These are due to rapid (<24 h) partitioning of the
surfactant into sediment and suspended particulates where it will remain strongly adsorbed with
low bioavailability. Further, this reduced exposure scenario will result in a reduction in the bio-
logical effects observed in the field when compared to those expected from Tier-1 hazard assess-
ments based on water-only standard tests and worst-case estimated environmental concentrations.
These results highlight the inappropriateness of simple screening-level approaches for the as-
sessment of the risk posed by compounds for which the expected exposure regimes may deviate
from that more typically used in traditional standard acute laboratory tests.
PREFACE
This thesis has been organized as a series of manuscripts (listed below). These manuscripts are
either published (Chapter 3), or will be submitted for publication in peer-reviewed journals. As a
result, some repetition of introductory and methodological information was unavoidable. José
Luis Rodríguez Gil wrote all manuscripts, as defined by primary authorship, with comments from
co-authors and anonymous reviewers associated with the publication process.
CHAPTER 2
Rodriguez-Gil, JL, Lissemore, L, Solomon, K, and Hanson, M. 2015. Dissipation of a commer-
cial mixture of polyoxyethylene amine surfactants in aquatic outdoor microcosms: Effect of water
depth and sediment organic carbon. In preparation. To be submitted to Environmental Science&
Technology
CHAPTER 3
Rodriguez-Gil, JL, Brain, R, Baxter, L, Ruffell, S, McConkey, B, Solomon, K, Hanson, M, 2014.
Optimization of culturing conditions for toxicity testing with the alga Oophila sp. (Chloro-
phyceae), an amphibian endosymbiont. Published in Environmental Toxicology and Chemistry
33, 2566-2575.
CHAPTER 4
Rodriguez-Gil JL, Prosser R, Mahon K, Hanta, G, Poirier D, Lissemore L, Thompson, D, Hanson
M, and Solomon K. 2015. Aquatic hazard assessment of MON 0818, a commercial mixture of
alkylamine ethoxylates commonly used in glyphosate-containing herbicide formulations. Part 1:
Species sensitivity distribution from laboratory acute exposures. In preparation, to be submitted
to Environmental Toxicology and Chemistry.
CHAPTER 5
Rodriguez-Gil, JL, Prosser, R, Mahon, K, Hanta, G, Poirier, D, Lissemore, L, Hanson, M, and
Solomon, K. 2015. Aquatic hazard assessment of MON 0818, a commercial mixture of alkyla-
mine ethoxylates commonly used in glyphosate-containing herbicide formulations. Part 2: Roles
of sediment, temperature, and capacity for recovery following a pulsed exposure. In preparation.
To be submitted to Environmental Toxicology and Chemistry.
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CHAPTER 6
Rodriguez-Gil, JL, Shokralla, S, de Jourdan, B, Lissemore, L, Sibley, P, Hajibabaei, M, Solomon,
K, and Hanson, M. 2015. Assessment of the effects of a polyoxyethylene tallow amine surfactant
mixture (MON 0818) in freshwater microcosms. In preparation. To be submitted to Environmen-
tal Toxicology and Chemistry.
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ACKNOWLEDGEMENTS

I would like to thank my advisory committee for their patience and support. First and foremost, I
would like to thank my advisors Dr. Keith Solomon and Dr. Mark Hanson for giving me the op-
portunity to come to Canada and learn from some of the best possible researchers in our field.
You both have always been there for me and my research; through all the battles with the analyti-
cal, and even in those times when all my other commitments might have distracted me a bit from
the thesis. From you I have learned, not only to be a better scientist, but a better person. If I stay
in academia, I hope I will be able to treat my students the way I was treated while I was here,
thank you.
I would like to thank Dr. Paul Sibley for ”adopting” me as his student and for being more than a
just a committee member. You have always been there when I needed someone in the ground
while Keith was away. I really enjoyed the teaching opportunities I had with you, whether while
being your TA or while co-mentoring students.
Finally I would like to thank Dr. Dean Thompson for his support and help, especially during the
latest stages. You were always able to see my research from a different perspective, and your
comments and suggestions truly helped improving the quality of what is presented in this thesis.
I have been extremely fortunate to get some incredible logistic support from everybody at the dif-
ferent venues where my research has taken place.
First, I would like to thank everybody involved in one way, or another in the endless battle to de-
velop the analytical method. I would like to start with Dr. Diane Brewer and Dr. Armen Char-
choglyan for their initial support in our attempts to develop the analytical method here in Guelph;
Dr. Andrew Ross and Dr. Xiangjun Liao for their help with the transfer of the final method to our
labs and for the preliminary analysis of an early sub-set of samples; Dr. Suzanne Mittermuller,
Dr. Vince Palace and Bailey Rankine, for their logistic support connecting our lab to the west-
coast; Dr. Linda Lissemore for running who knows how many hundreds of samples and always
being flexible with my timelines; Dr. Derek Muir and Dr. Amila de Silva for sharing their labs
and resources with me, there wouldn’t be a thesis without your generosity; everybody that helped
mw while at CCIW: Christine Spencer and Tom Pear for their help and suggestions, and especial-
vi
ly Mary Williamson for her invaluable help on the development of the sediment extraction meth-
od and for hosting me in her office for what was supposed to be a couple of weeks and ended up
being 6 months.
I would like to thank Dr. David Poirier, Kim Mahon and everybody at the Aquatic Toxicology
Unit of the MOE CC for all their invaluable help and for providing me with the best quality test
organisms a toxicologist could ask for. Than you, also, to Gregory Hanta, for his help running the
Lemna tests.
I would like to thank Peter Purvis and everybody at the GTI for all the assistance during the mul-
tiple summers I spent at the ponds. Of course, I would like to give a big thanks to everybody that
came to my rescue when I needed extra hands to mix sediment, sample, or just get a ride to the
ponds: Ben, Leilan, Ryan, Mark, Julie, Paddy, Hamish, Lindsey, Will, Andrew, Istiania, Hugo,
Laura and anyone that I might (unfairly) be forgetting right now.
Thank you to Dr. Mehrdad Hajibabaei, and Dr. Shadi Shokralla for thinking that our research was
worth investing some time and resources on. I am sure there will be future chances to collaborate.
I would like to thank Steven Levine, Mitchell Kurtzweil, and Joy Honegger from Monsanto
Company and Spencer Mortensen from the Glyphosate Task Force for their advice and for sup-
plying the surfactant used in this thesis.
Thank you, also, to Syngenta Crop Protection for funding the studies relating to Ooophyla sp.;
Dr. J. Bogart for his expert advice on the biology of Ambystoma maculatum; Dr. Ben de Jourdan
for his assistance during the sampling of the egg masses; and Dr. Richard Frank for his advice on
algal isolation techniques
I would like to thank the “La Caixa” Foundation for their initial support and for allowing me to
take this chance, as well as the NSERC CREATE program in human and Environmental Risk
Assessment for the funding during the last few years and the opportunity to travel to Saskatoon to
learn and meet other colleagues and friends. Thank you, also to Keith, for filling-in the gaps be-
tween funding periods.

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On a more personal note, the biggest thank you goes to my family for always being there for me,
they never doubted I could make it and they always loved me, even when I never call home. You
made me the way I am, and in that way you are the ones that made it, and not me. Gracias!
Incredible thank you to my Canadian brother, Ben, and my Canadian family. You have taken my
as another de Jourdan, and I have no words to start thanking you for all you have done. I know
that my mom sleeps much better knowing that I have someone taking care of me on this side of
the Ocean.
Thank you to my Bestie, Shwana, for your incredible support and patience, for always giving me
that extra boost of confidence, for keeping me fed on the looooong days of the last stretch, and
being there to let me rant after long days. I hope I can return the favour very very soon! I can’t
wait for our next adventures!
Thank you to all my incredible friends here in Guelph. Those who are still here and those that
moved on to their own next adventures. Lei, Hamish, Ellen, Jordana, Paddy, Dana, Becca, Lisa…
you all have put up with all my silliness and helped me feel welcomed in Guelph. I will always
remember these years! Thank you to my roommates over these years Dave and Huguito, you
both, in your own way, have made my daily live a bit easier to enjoy!; my Spanish-speaking
friends (Thank you Mari!); everybody in SES, current and gone! And everybody that shared my
time at the GSA. And of course the best office-mate ever, Ryan. You have been an incredible in-
spiration and a good motivator. I hope we will keep on collaborating in some of the best tox re-
search out-there!
A final (unusual) thank you goes to Doogies and the incredible Test Icicles, for always providing
a nice ecape from our busy lives and a place where we could all go and reset our brains. I think
you guys have kept us all sane! It will be hard to find a place like that!
If you are not in this list is not because I don’t thank you, but because I couldn’t have a 10 page
acknowledgement… I couldn’t have made it without you all.

Thank you…
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TABLE OF CONTENTS
ABSTRACT .................................................................................................................................... ii
PREFACE ...................................................................................................................................... iv
ACKNOWLEDGEMENTS ......................................................................................................... vi
TABLE OF CONTENTS ............................................................................................................. ix
LIST OF TABLES ...................................................................................................................... xiii
LIST OF FIGURES .................................................................................................................... xxi
Chapter 1 Introduction .............................................................................................................. 1
1.1. Thesis overview ................................................................................................................. 1
1.2. Background ........................................................................................................................ 2
1.3. Problem formulation and working hypotheses ................................................................ 16
1.4. Research Objectives ........................................................................................................ 20
Chapter 2 Dissipation of a Commercial Mixture of Polyoxyethylene Amine Surfactants in
Aquatic Outdoor Microcosms: Effect of Water Depth and Sediment Organic Carbon ....... 24
2.1. Abstract ............................................................................................................................ 24
2.2. Introduction ..................................................................................................................... 25
2.3. Materials and methods ..................................................................................................... 27
2.4. Results ............................................................................................................................. 34
2.5. Discussion ........................................................................................................................ 37
2.6. Tables .............................................................................................................................. 41
2.7. Figures ............................................................................................................................. 44
Chapter 3 Optimization of Culturing Conditions for Toxicity Testing with the Alga
Oophila sp. (Chlorophyceae), an Amphibian Endosymbiont ................................................... 47
3.1. Abstract ............................................................................................................................ 47
3.2. Introduction ..................................................................................................................... 47
3.3. Materials and methods ..................................................................................................... 49
ix
3.4. Results ............................................................................................................................. 57
3.5. Discussion ........................................................................................................................ 60
3.6. Tables .............................................................................................................................. 63
3.7. Figures ............................................................................................................................. 65
Chapter 4 Aquatic Hazard Assessment of MON 0818, a Commercial Mixture of
Alkylamine Ethoxylates Commonly Used in Glyphosate-Containing Herbicide
Formulations. Part 1: Species Sensitivity Distribution from Laboratory Acute Exposures . 71
4.1. Abstract ............................................................................................................................ 71
4.2. Introduction ..................................................................................................................... 72
4.3. Materials and methods ..................................................................................................... 75
4.4. Results ............................................................................................................................. 80
4.5. Discussion ........................................................................................................................ 82
4.6. Tables .............................................................................................................................. 86
4.7. Figures ............................................................................................................................. 90
Chapter 5 Aquatic Hazard Assessment of MON 0818, a Commercial Mixture of
Alkylamine Ethoxylates Commonly Used in Glyphosate-Containing Herbicide
Formulations. Part 2: Roles of Sediment, Temperature, and Capacity for Recovery
Following a Pulsed Exposure ...................................................................................................... 93
5.1. Abstract ............................................................................................................................ 93
5.2. Introduction ..................................................................................................................... 94
5.3. Materials and methods ..................................................................................................... 97
5.4. Results ........................................................................................................................... 103
5.5. Discussion ...................................................................................................................... 105
5.6. Tables ............................................................................................................................ 109
5.7. Figures ........................................................................................................................... 113
Chapter 6 Assessment of the Effects of a Polyoxyethylene Tallow Amine Surfactant
Mixture (MON 0818) in Freshwater Microcosms ................................................................... 118
6.1. Abstract .......................................................................................................................... 118
x