March 31, 2016 Polyoxyethylene tallow amine

206 Pages·2016·6.71 MB·English

Polyoxyethylene tallow amine:
Environmental fate of an "inert" ingredient
By
Daniel Tush
Submitted to the graduate degree program in Chemistry and the Graduate Faculty
of the University of Kansas in partial fulfillment of the requirements for the degree of
Doctor of Philosophy.
______________________________________________
Michael T. Meyer, Primary Investigator, Co-Chairperson
______________________________________________
Robert C. Dunn, Chairperson
______________________________________________
Susan M. Lunte
______________________________________________
Heather Desaire
______________________________________________
Edward F. Peltier
Date Defended: March 31, 2016
The Dissertation Committee for Daniel Tush
certifies that this is the approved version of the following dissertation:
Polyoxyethylene tallow amine: Environmental fate of an "inert" ingredient
______________________________________________
Michael T. Meyer, Primary Investigator, Co-Chairperson
______________________________________________
Robert C. Dunn, Chairperson
Date approved: April 14, 2016
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Abstract

The surfactant polyoxyethylene tallow amine (POEA) is a common inert ingredient in
formulations of glyphosate—the most widely applied agricultural herbicide in the world, which
is also commonly used in urban settings. Little is known about the environmental occurrence,
fate, and effects of ancillary additives such as POEA. POEA is not well characterized in the
literature, but has been shown to be toxic to numerous aquatic organisms. Characterization of
POEA technical mixtures shows that POEA is a complex combination of a central nitrogen atom,
different aliphatic moieties, and varying numbers of ethoxylate units. Analysis of several
agricultural and household glyphosate formulations confirmed that different POEA technical
mixtures are common additives in these formulations and that a POEA technical mixture with an
average of 15 ethoxylate units is the most common additive. Experiments to characterize the
adsorption of POEA to soils revealed that POEA adsorbs much stronger to soil than glyphosate;
the addition of calcium chloride to the system increases the adsorption of POEA; and the
adsorption of POEA to soils was highest in low pH conditions. POEA detected on a soil sample
from a row crop agricultural field near Lawrence, Kansas shows a change in the distribution of
homologs over time with a loss of homologs that contain an alkene moiety. POEA was also
detected on row crop agricultural soil samples collected between February and early March from
sites in five other states (Iowa, Illinois, Indiana, Missouri, Mississippi). Soil samples collected
from a row crop field in Indiana for over a year were analyzed to examine the dissipation of
POEA, glyphosate, and aminomethylphosphonic acid (AMPA) and shows that POEA and
glyphosate persist on the shallow soil from growing season to growing season but there is some
dissipation over time with little migration into deeper soil. Stream bed sediments (agricultural
and urban watersheds) from six states (Georgia, Hawaii, Iowa, Mississippi, North Carolina,
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South Carolina) were analyzed and all were found to have detectable levels of POEA. This is the
first indication of the potential widespread contamination of POEA on agricultural soils and
stream bed sediments in areas where glyphosate is applied.

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Acknowledgements
There are far too many people (both real and fictional) who have influenced my life to
bring me to where I am now to thank them all properly within these pages. I’d like to thank you
all. I count many of you among my family, my friends, my colleagues, my teachers, and my
inspirations. There are a handful of individuals and groups that I would like to mention
specifically. I will list them (like some movie credits) in order of appearance. For those who I
don’t mention by name, I mean no slight. I am no poet and only have so many words.
From the beginning of my story, my parents have always been there. My mother, Nancy
Tush, has always been one of my biggest supporters. She would always pick me up when I fell
down and always encouraged me no matter which direction the path of my life took. My father,
Richard Tush, and I often don’t see eye to eye on a great many topics, but his appreciation of the
natural world around us is one of the cornerstones in my appreciation of the sciences.
My oldest friend, Rebecca Schoonover, is the reason I survived school, K-12. In some
ways she and I are completely different people and yet I’ve always found we were more than
enough the same in all the ways that matter. She was the shining morning star that kept me
getting up each morning and going to school (and giving at least some effort at it while I was
there).
Another good friend, Jack Kirkham III, appeared in the story somewhat later, but with no
less importance. We both played the role of best man at each other’s wedding, although I must
say that he did it better. I often played the straight man to his fool, an odd couple of sorts. There
is no one I counted on more to randomly show up and go shoot hoops with (often when I needed
it the most).
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One of my favorite teachers at any level, Sam Wine, also shares a role in developing my
interest in science. He taught Earth/Space Science, Chemistry, and Physics in my high school.
His enthusiasm for all of these topics was undeniable and infectious. Although after high school,
I went away from pure sciences for a time, his teachings were there to help guide me back.
The last of my friends to join the cast during the high school era was Lee Van Dyke. I
wouldn’t even hazard a guess to the number of hours we spent waxing philosophical in the
tower, and I also can’t begin to explain how important those hours were. No matter how idle or
how deep the conversations were in those hours, not one was wasted in my eyes.
It seems like a lifetime ago when I left high school for college to study computer science.
Although my career path has left that degree largely in the dust, it was still an important time.
For one, I met a fellow computer nerd who’s career path has been similar and yet quite different
than mine. We both worked as programmers for a time, I left the field to study chemistry and he
entered the Seminary. Father Matt Cushing is one of the most caring, most generous people I
have ever met.
In this day and age, it sounds less and less odd to say you met a person online. I met
Wendy Purches on an internet forum. I’d like to say we were immediate friends, but we started
out as a nemesis for each other. And yet, through the years and several different forums, we
became friends. It was Wendy that, somewhat idly, suggested I go into chemistry after I left the
programing world (she was at the time studying chemistry). And, well, I did. So far it looks like
it is working out.
I would not have made the transition from being a professional programmer to being a
chemistry student at Emporia State University without the guidance of my advisor, teacher, and
friend—Dr. Jim Roach. From the beginning of my time at Emporia, he showed nothing but
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absolute faith in my abilities. In fact, I’d wager that he still believes I’m capable of more than I
think I am. We also found common interests outside of the university (mostly Star Wars, Star
Trek, and Lost).
I would also like to thank the Chemistry Department at the University of Kansas. They
provided great opportunities and even when those didn’t work out, they allowed me to pursue an
opportunity to do research outside the chemistry mainstream. We leads me to thank the U.S.
Geological Survey—more specifically the Organic Geochemistry Research Laboratory at the
Kansas Water Science Center. The director of the lab, Dr. Michael Meyer, took in a wayward
student that he had no obligation to. I would not have the opportunity to write this section in this
dissertation without his support.
Finally, and out of order (sorry!), I would like to thank my wife, Dr. Rachael Lane. I
have already listed most of the people in the known universe who can put up with me and she
has to put up with a lot more of me more of the time. Her help was immeasurable in completing
this dissertation (she had to go through the process first and so had firsthand experience). I don’t
know where I would be without her, but it certainly wouldn’t be as good as it is now.
Thank you, one and all.
Huzzah!

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Table of Contents
Chapter 1: Introduction to Polyoxyethylene Tallow Amine ..................................................... 1
1.1 Polyoxyethylene Tallow Amine: Structure, Naming, and Synthesis ............................. 1
1.2 Use of Polyoxyethylene Tallow Amine in Glyphosate Formulations ............................ 3
1.2.1 History of Glyphosate ................................................................................................... 3
1.2.2 Improved Efficacy of Glyphosate ............................................................................... 14
1.3 Effects of Polyoxyethylene Tallow Amine...................................................................... 14
1.3.1 Toxicity to Non-Target Organisms ............................................................................. 14
1.3.2 Human Health ............................................................................................................. 15
1.3.3 Other Effects ............................................................................................................... 15
1.4 Instrumental Analysis of Polyoxyethylene Tallow Amine ........................................... 17
1.5 Other Surfactants in the Environment .......................................................................... 20
1.6 Research Objectives ......................................................................................................... 21
1.7 References ......................................................................................................................... 23
Chapter 2: Characterization of polyoxyethylene tallow amine surfactants in technical
mixtures and glyphosate formulations using ultra-high performance liquid
chromatography and triple quadrupole mass spectrometry .................................................. 32
2.1 Introduction ...................................................................................................................... 32
2.2 Experimental .................................................................................................................... 38
2.2.1 Reagents and Materials ............................................................................................... 38
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2.2.2 Chromatographic Systems .......................................................................................... 39
2.2.3 Mass Spectrometry...................................................................................................... 41
2.2.4 Peak Fitting ................................................................................................................. 41
2.3 Results and Discussion ..................................................................................................... 42
2.3.1 Characterization of POEA .......................................................................................... 42
2.3.1.1 POE (2) Tallow Amine ........................................................................................ 42
2.3.1.2 POE (5) Tallow Amine ........................................................................................ 44
2.3.1.3 POE (15) Tallow Amine and Ethomeen T/25...................................................... 47
2.3.2 Comparison of Analytical Columns............................................................................ 48
2.3.3 Survey of commercial glyphosate formulations ......................................................... 53
2.4 Conclusions ....................................................................................................................... 57
2.5 References ......................................................................................................................... 59
Chapter 3: Polyoxyethylene Tallow Amine, a Glyphosate Formulation Adjuvant: Soil
Adsorption Characteristics, Degradation Profile, and Occurrence on Selected Soils from
Agricultural Fields in Iowa, Illinois, Indiana, Mississippi, and Missouri .............................. 64
3.1 Introduction ...................................................................................................................... 64
3.2 Materials and Methods .................................................................................................... 68
3.2.1 Chemicals and Reagents ............................................................................................. 68
3.2.2 Soils............................................................................................................................. 69
3.2.3 Adsorption Experiments ............................................................................................. 69
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3.2.4 Soil Extraction Method ............................................................................................... 70
3.2.5 Analytical Methods ..................................................................................................... 70
3.3 Results and Discussion ..................................................................................................... 71
3.3.1 Adsorption of POEA to Soil ....................................................................................... 71
3.3.2 Effects of Salt Content on the Adsorption of POEA .................................................. 74
3.3.3 Effects of pH on the Adsorption of POEA ................................................................. 81
3.3.4 Total POEA Freundlich Averages .............................................................................. 83
3.3.5 Field Samples .............................................................................................................. 85
3.4 Supporting Information ................................................................................................... 89
3.4.1 Methods........................................................................................................................ 89
3.4.1.1 Sample Collection ................................................................................................. 89
3.4.1.2 Laboratory Glassware ........................................................................................... 90
3.4.1.3 POEA Standards ................................................................................................... 90
3.4.1.4 POEA-Pyrex Centrifuge Tube Adsorption Experiments ...................................... 90
3.4.1.5 Soil Adsorption Experiments. ............................................................................... 92
3.4.1.6 Soil Extraction Method ......................................................................................... 92
3.4.1.7 Analytical Method ................................................................................................ 93
3.4.2 Effects of Soil Composition on the Adsorption of POEA ........................................... 94
3.4.3 Tables ........................................................................................................................... 96
3.4.4 Figures........................................................................................................................ 100
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