Factors affecting the choice of

aquatic surfactants

Kim Patten

WSU Long Beach

*Caveats*

So what’s the big deal about

surfactants? There are over 3000 adjuvants on the market.

Surfactant use in aquatic environments is perceived to be a major concern by many environment groups.

Outline

• Background information on Adjuvants – What do they do and why we need them?

• Aquatic Adjuvant – When do they make a difference?

– What works the best (which ones and at what rate)?

• The toxicity story – How hot are they

• Putting it all together for the big picture

What do they do and why we need them?

Adjuvants

Utility Adjuvants

Activator Adjuvants

Wetter Spreader

Sticker Humectant

Penetrator Defoamer

Water Conditioner

surfactants oils

glycerin COC’s MSO’s

AMS

Acids

metho-polysiloxane

Slide courtesy of S. Nissen

Activities of a Good Adjuvant

Good Activities

Reduces surface tension

Prevents Crystallization

Improves Absorption

Improves Retention

Improves Mixing

Improved Activity

Slide courtesy of S. Nissen

Slide courtesy of J Vollmer

Slide courtesy of J Vollmer

Improves Absorption

Cuticle is the most important barrier to absorption.

Dodi Kazarian Slide courtesy of S. Nissen

Slide courtesy of J Vollmer

Slide courtesy of J Vollmer

Slide courtesy of J Vollmer

C H 3 C H

3 C H 3

C H 3

O O

O

O O

O

O

O O

O H

Longer EO chains better for hydrophyilic

pesticides, like Habitat

Polar

Non-polar

Slide courtesy of S. Nissen

Shorter EO chains better

for lipophyilic pesticides

Slide courtesy of J Vollmer

Habitat label specify a surfactant w/ a HLB 12-17

Grass herbicides like Poast specify a surfactant w/ a low HLB (3-6)

HLB’S ??

13 8 13 9 9

Clear milky after shaking clear stable milky stable milky

• Aquatic Adjuvant

– When do they make a difference?

– What works the best (which ones and what rate)?

Name Ingredients

LC50 96 hour

mg/l RAINBOW

TROUT

LC50 48hour

mg/l

DAPHNIDS

Agri-Dex Petroleum oil, polyoxyethylene sorbitan fatty acid ester, sorbitan

fatty acid ester 1000 1000

AquaSurf Petroleum oil, saccharides, polyoxyethylene sorbitan fatty acid

ester 100 100

Bond Synthetic latex, alcohol ethoxylate 190 614

Bronc Max Ammonium sulfate, dodecylbenzenesulfonic acid sodium salt,

citric acid, dimethylpolysiloxane 100 100

Bronc Plus Dry-

EDT

Ammonium sulfate, urea, polyoxyethylene-polyoxypropylene

copolymer, citric acid, polyacrylamide, dimethylpolysiloxane 383 224

Class Act NG Ammonium sulfate, saccharides, alkyl polyglycoside 447 377

Competitor Modified vegetable (seed) oil, polyethylene glycol fatty acid ester,

polyoxyethylene sorbitan fatty acid ester 95 100

Rate Ammonium sulfate, citric acid 782 224

Cygnet Plus Limonene, modified vegetable (seed) oil, alcohol ethoxylate 45 7

Destiny HC Modified vegetable (seed) oil, saccharides, sorbitan fatty acid

ester 22 29

Dyne-Amic Modified vegetable (seed) oil, polysiloxane polyether copolymer,

alkyl phenol ethoxylate 23 60

Exciter Ammonium sulfate, ammonium nitrate, alkyl polyglycoside 100 8

Fraction Ammonium sulfate, citric acid 782 224

InterLock Modified vegetable (seed) oil, polyoxyethylene sorbitan fatty acid

ester, vegetable (seed) oil 100 100

Kinetic Polysiloxane polyether copolymer, polyoxypropylene-

polyoxyethylene copolymer 14 61

Level 7 Ammonium sulfate, citric acid, saccharides 100 100

LI 700 Lecithin, propanoic (propionic) acid, alkyl phenol ethoxylate 130 190

Liberate Lecithin, alcohol ethoxylate, modified vegetable (seed) oil 18 9

Magnify Ammonium sulfate, ammonium nitrate, alkyl polyglycoside 100 8

One-AP XL

Ammonium sulfate, urea, polyoxyethylene-polyoxypropylene

copolymer, citric acid, polyvinyl polymer (polyacrylamide),

dimethylpolysiloxane

383 224

Pro AMS Plus Ammonium sulfate, ammonium nitrate, alkyl polyglycoside 100 8

Sinker Polyvinyl polymer (Polyacrylamide), alkylphenol ethoxylate,

sorbitan fatty acid ester 750 1000

Spray-Rite Ammonium sulfate, citric acid 782 224

Superb HC Petroleum oil, saccharides, polyoxyethylene sorbitan fatty acid

ester 45 100

Tactic Synthetic latex, propylene glycol, alcohol ethoxylate, polysiloxane

polyether copolymer 100 310

Tronic Vegetable (seed) oil ethoxylate, tall oil fatty acids 200 29

Know

what the

product

does!

Sticker

Acidulant

Acidulant

Acidulant

Sinking agent

Acidulant

Surfactant Type of surfactant

R-11 NIS

Cygnet Plus NIS

Liberate NIS

Class Act Next Generation NIS, water conditioning

LI-700 NIS, acidifier

Kinetic NIS with silicone

Dyne-Amic NIS/MSO/penetrant with silicone

Agri-Dex Paraffin based petroleum oil (COC) / NIS

Competitor Esterfied vegetable oil (MSO)

Bond Latex spreader-sticker

Tactic Latex spreader- sticker with silicon

Sinker Sinking agent

Intensify Ammoniated salt surfactant blend

Exciter Ammoniated salt surfactant blend

Magnify Ammoniated salt surfactant blend

Name Ingredients

Kinetic Polysiloxane polyether copolymer, polyoxypropylene-polyoxyethylene copolymer

Liberate Lecithin, alcohol ethoxylate, modified vegetable (seed) oil

Destiny HC Modified vegetable (seed) oil, saccharides, sorbitan fatty acid ester

Dyne-Amic Modified vegetable (seed) oil, polysiloxane polyether copolymer, alkyl phenol

ethoxylate

Cygnet Plus Limonene, modified vegetable (seed) oil, alcohol ethoxylate

Superb HC Petroleum oil, saccharides, polyoxyethylene sorbitan fatty acid ester

Competitor Modified vegetable (seed) oil, polyethylene glycol fatty acid ester, polyoxyethylene

sorbitan fatty acid ester

AquaSurf Petroleum oil, saccharides, polyoxyethylene sorbitan fatty acid ester

Bronc Max Ammonium sulfate, dodecylbenzenesulfonic acid sodium salt, citric acid,

dimethylpolysiloxane

Exciter Ammonium sulfate, ammonium nitrate, alkyl polyglycoside

InterLock Modified vegetable (seed) oil, polyoxyethylene sorbitan fatty acid ester, vegetable

(seed) oil

Tactic Synthetic latex, propylene glycol, alcohol ethoxylate, polysiloxane polyether copolymer

LI 700 Lecithin, propanoic (propionic) acid, alkyl phenol ethoxylate

Tronic Vegetable (seed) oil ethoxylate, tall oil fatty acids

Bronc Plus Dry-EDT Ammonium sulfate, urea, polyoxyethylene-polyoxypropylene copolymer, citric acid,

polyacrylamide, dimethylpolysiloxane

One-AP XL Ammonium sulfate, urea, polyoxyethylene-polyoxypropylene copolymer, citric acid,

polyvinyl polymer (polyacrylamide), dimethylpolysiloxane

Class Act NG Ammonium sulfate, saccharides, alkyl polyglycoside

Agri-Dex Petroleum oil, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester

What does the herbicide label recommend?

NIS, COC, MSO or Hybrid?

Does the label recommend a HLB ratio?

Surfactants are not silver bullets.

You must first have

• An adequate amount of canopy exposed

and treated

• The correct herbicide rate

• Ample length of exposure prior to washoff

• Good canopy quality

Rules for success in aquatic weed

control

• Adequate amount of canopy

Smith et al. 1999. JAPM

Parrotfeather Milfoil control as a function

of depth of canopy above the water

poor

good

Rules for success in aquatic weed

control

• Correct herbicide rate

% c

on

tro

l

0

20

40

60

80

100

9 kg/ha 18 kg/ha 24 kg/ha

Box Whisker graph

medium, 10 and 90th percentile

bars =5th & 95th percentiles

Spartina control (%) across all research plot 1998 to 2003

as a function of glyphosate rate

Patten 2004

Rules for success in aquatic weed

control

• Length of exposure prior to washoff

Smith et al. 1999. JAPM

0

20

40

60

80

100

imazapyr

glyphosate

>7 hrs >7hrs4-7hrs

4-7hrs

% S

pa

rtin

a c

on

tro

l

Efficacy comparison for 6 pt/ac Habitat and

4 gal/ac Aquamaster as a function of dry times*

* Pooled data from all experiment between 1999 to 2002; Spray volume <20 gpa

Patten 2004

ALT #2710

0

100

200

300

400

500

0 0.5 1 1.5 2

[glyphosate] (%)

gly

ph

osate

up

take (

d15N

)

clean

muddy

Effect of leaf sediment on glyphosate uptake

Rules for success in aquatic weed control

• Canopy quality

Defining surfactant efficacy depends on where you

are on the efficacy graph!

Typical weed control with and without an adjuvant %

Weed C

ontr

ol

0

20

40

60

80

100

0 0.25x 0.5x 1x 1.5x 2x 3x

Herbicide rate

With

Without

Effect of surfactant on the efficacy of imazapyr*

% control

0 20 40 60 80 100

Syl-tac 1%

Dyn-Amic 1%

Kinetic 0.5%

Hasten 1%

Agri-Dex 2%

Agri-Dex 1%

* 6 pt/ac, 10 gpa, >6 hrs dry time

No significant difference between treatments

Long dry time – no surfactant effect

Spartina control

Spartina control with imazapyr as a function of surfactant

% c

ontr

ol

0

20

40

60

80

100

1% Hasten 1% Competitor 1% Agridex

6 pt/ac, 20 gpa spray volume on spartinameadow with 4 hours dry time

(surfactant @ 1 qt/ac)

Short dry time – surfactant effect

Efficacy of Rodeo as Affected by Surfactants - 2000

Rodeo +R11

Rodeo +Agrid

ex

Rodeo + K

inetic

Rodeo +

Li7

00

Rodoe + D

ynam

ic

Rodeo + S

yltac

Arsenal

% C

ontr

ol

0

20

40

60

80

100

Rodeo applied @ 7.5 qt/ac using 1% v/v (0.4 qt/ac) surfactant @

10 gpa on 8/8/00 @ flowering, 8hrs dry time

Spartina control with Aquamaster as a function of surfactant

% c

ontr

ol

0

20

40

60

80

100

120

1% R11 1% Agridex 1% Class ActNext

Generation

5% spray to wet, 10-3-03, mixture of young clones and meadows >6 hours dry time

0102030405060708090

Agr

idex

0.4

qt/a

c (1

%)

Agr

idex

0.8

qt/a

c (2

%)

Agr

idex

1.6

qt/a

c (4

%)

Li700

0.4

qt/a

c (1

%)

Li700

0.8

qt/a

c (2

%)

Li700

1.6

qt/a

c (4

%)

Kin

etic

0.1

qt/a

c (.2

5%)

Kin

etic

0.2

qt/ac

(.5%

)

Kin

etic

0.4

qt/a

c (1

%)

Dyn

amic

0.2

qt/a

c (.5

%)

Dyn

amic

0.4

qt/a

c (1

%)

Dyn

amic

0.8

qt/a

c (2

%)

Rodeo @ 2 gallons/ac applied at 10 gpa spray volume

Efficacy as a function of Surfactant & Rate

% S

pa

rtin

a c

on

tro

l 1

4 m

at

• The toxicity story – Lots of horror stories based on the Orginal Roundup

Formulation with Mon 0818 - tallow amine (nonyl

phenol ethoxylate (NPE)

– New formulations are less toxic

– Aquatic formulations don’t have surfactants

Median lethal concentration (LC50) values of glyphosate-based herbicide for

amphibian larvae of 37 species. All values are in milligrams acid equivalent per liter

(mg a.e./L)

Aquatic based glyphosate Terrestrial based glyphosate

Wagner et al. 2013, Env Tox & Chem

alkylphenol ethoxylate vs. nonyl phenol ethoxylate

AE NPE or POEA

Bio-degradability Readily Not readily

Concern about acute

toxicity to fish

No yes

Breakdown products

more toxic than

parent compounds

No yes

Predicted chronic no

effect concentration

110 ug/l 0.33 ug/l

Endocrine disruptor No Yes

Rainbow trout Basic Acute Toxicity

Source - unknown

Curran, C.A., J.M. Grassley and C.E. Grue. 2004. Toxicity of R-11® surfactant to juvenile rainbow

trout: Does size matter? Bulletin of Environmental Contamination and Toxicology 72:401-408 and

http://training.fws.gov/resources/course-

resources/pesticides/Aquatic%20Effects/Toxicity%20of%20Surfactants%20to%20Trout.pdf

Name LC50 96 hour mg/l RAINBOW TROUT

Mon 0818 2

X77 2

R11 6

Li700 17

Hasten 74

Agridex 271

Roundup 8

Rodeo 786

Habitat 77716

Rodeo + R11 5

Rodeo + Li700 22

Hatitat + Hasten 113

Habitat + Agridex 479

NPE’s

Conclusion: Surfactant – makes the poison!

What about synergy or additive effects - we are spray the a tank mix

not single ingredients?

Name

LC50 96 hour mg/l

RAINBOW TROUT

LC50 48hour mg/l

DAPHNIDS

Cygnet Plus 45 7

Exciter 100 8

Liberate 18 9

Destiny HC 22 29

Tronic 200 29

Dyne-Amic 23 60

Kinetic 14 61

Superb HC 45 100

Competitor 95 100

AquaSurf 100 100

Bronc Max 100 100

InterLock 100 100

LI 700 130 190

Bronc Plus Dry-EDT 383 224

One-AP XL 383 224

Tactic 100 310

Class Act NG 447 377

Agri-Dex 1000 1000

Approved Aquatic Surfactants – WSDA (see website)

Being on a

list does

not infer

they are the

only safe

surfactants,

only that

you filled

out the

paper work.

http://www.ecy.wa.gov/programs/wq/pesticides/enviroReview/riskAssess/AqjuvantAquaticT

ox2012.pdf

0

0.2

0.4

0.6

0.8

1

1.2

1.4

2.5 5 10 20 40 80

Application Rate (gal/acre)

Ha

za

rd Q

uo

tie

nt

R-11

LI-700

HASTEN

AGRI-DEX

Take home – dose makes the poison &

dose is a function of surfactant concentration and spray volume.

Spraying with 1% R11 at > 50 gpa exceeds HQ.

Hazard Quotient ( estimated

water concentration/LC50) for surfactants is a function of spray volume

160 320

High Pressure

Hand Application

Broadcast

Application

Smith, B. C., et al. "Toxicity of four surfactants to juvenile rainbow trout: implications for use over water." Bulletin of

environmental contamination and toxicology 72.3 (2004): 647-654.

Surfactant PPM

at recommended

use rate in 2” of

water

LC 50

trout*

Hazard quotient

(concentration in water/LC50)

Agri-Dex 1%v/v at

100 gpa

18 271 0.07

Competitor 1qt/ac 4.5 ~70 0.06

R-11 1%v/v @

100 gpa

18 6 3

*Data

from

Grue At least two orders of

magnitude of safety for fish

Name Ingredients

LC50 96 hour

mg/l RAINBOW

TROUT

LC50 48hour

mg/l

DAPHNIDS

Agri-Dex Petroleum oil, polyoxyethylene sorbitan fatty acid ester, sorbitan

fatty acid ester 1000 1000

AquaSurf Petroleum oil, saccharides, polyoxyethylene sorbitan fatty acid

ester 100 100

Bond Synthetic latex, alcohol ethoxylate 190 614

Bronc Max Ammonium sulfate, dodecylbenzenesulfonic acid sodium salt,

citric acid, dimethylpolysiloxane 100 100

Bronc Plus Dry-

EDT

Ammonium sulfate, urea, polyoxyethylene-polyoxypropylene

copolymer, citric acid, polyacrylamide, dimethylpolysiloxane 383 224

Class Act NG Ammonium sulfate, saccharides, alkyl polyglycoside 447 377

Competitor Modified vegetable (seed) oil, polyethylene glycol fatty acid ester,

polyoxyethylene sorbitan fatty acid ester 95 100

Rate Ammonium sulfate, citric acid 782 224

Cygnet Plus Limonene, modified vegetable (seed) oil, alcohol ethoxylate 45 7

Destiny HC Modified vegetable (seed) oil, saccharides, sorbitan fatty acid

ester 22 29

Dyne-Amic Modified vegetable (seed) oil, polysiloxane polyether copolymer,

alkyl phenol ethoxylate 23 60

Exciter Ammonium sulfate, ammonium nitrate, alkyl polyglycoside 100 8

Fraction Ammonium sulfate, citric acid 782 224

InterLock Modified vegetable (seed) oil, polyoxyethylene sorbitan fatty acid

ester, vegetable (seed) oil 100 100

Kinetic Polysiloxane polyether copolymer, polyoxypropylene-

polyoxyethylene copolymer 14 61

Level 7 Ammonium sulfate, citric acid, saccharides 100 100

LI 700 Lecithin, propanoic (propionic) acid, alkyl phenol ethoxylate 130 190

Liberate Lecithin, alcohol ethoxylate, modified vegetable (seed) oil 18 9

Magnify Ammonium sulfate, ammonium nitrate, alkyl polyglycoside 100 8

One-AP XL

Ammonium sulfate, urea, polyoxyethylene-polyoxypropylene

copolymer, citric acid, polyvinyl polymer (polyacrylamide),

dimethylpolysiloxane

383 224

Pro AMS Plus Ammonium sulfate, ammonium nitrate, alkyl polyglycoside 100 8

Sinker Polyvinyl polymer (Polyacrylamide), alkylphenol ethoxylate,

sorbitan fatty acid ester 750 1000

Spray-Rite Ammonium sulfate, citric acid 782 224

Superb HC Petroleum oil, saccharides, polyoxyethylene sorbitan fatty acid

ester 45 100

Tactic Synthetic latex, propylene glycol, alcohol ethoxylate, polysiloxane

polyether copolymer 100 310

Tronic Vegetable (seed) oil ethoxylate, tall oil fatty acids 200 29

Natural

ingredients

doesn’t

mean

anything!

Aside from acute

toxicity to fish –

Environmental

groups are concerns

about surfactants

because of

estrogenic effects

on fish and frogs

http://www.trentu.ca/biology/berrill/Re

search/Roundup_Poster.htm

Also see

Yahnke, A. E., Grue, C. E., Hayes, M.

P. and Troiano, A. T. (2013), Effects

of the herbicide imazapyr on juvenile

Oregon spotted frogs. Environmental

Toxicology and Chemistry, 32: 228–

235.

So after all of this, what is the take

home message about surfactant

choice?

• What do I recommend for each herbicide

and why?

– What is on the herbicide label?

– What is on the surfactant label?

NIS MSO COC Silicon

Habitat >0.25% v/v of HLB 12-17* w/ 70% surfactant

1.5-2 pt/ac @

<30 gpa

1% @>30 gpa

See manufacture

label

Rodeo

Aquamaster

>0.5% v/v (100 gpa based)

w/ 50% surfactant

Renovate For floating weeds

See manufacture label

Reward “label is potential

vague”

Doesn’t specify mixing rate

on label, Company rep.

says 0.25% v/v of a NIS

with >75% surfactant

2,4-D

Herbicide label recommendations re: surfactants

* Turns clear in a 1:1 mixture of water

Competitor (98% ai) 2-4 pints/100 gallons

R11 (90% ai) 64 oz/100 gallon

Agridex (99% ai) w/ 17%

surfactant content

1-4 pt/ac do not exceed 2.5% v/v

Dyne-Amic 0.38 to 0.75 % v/v 3-6pt/100 gallon

Kinetic (100% ai) w/

99% surfactant

8 to 32 oz/100 gallon

Sinker (30% ai) Injections 1-5 gal/100 gal;

Spray 6-16 oz/100 gal <45 psi & 16 -64 oz.10 gal >50 psi

LI700 (80% surfactant ai) 1-4 pt/100 gallon as penetrant

12 oz to 2 pt/ac as COC

Bond as a sticker 1-2 pt/100 gallons 2-4 oz/ac

Cygnet plus ? 0.25% v/v

Liberate 1 to 4 pt/100 gallons as a penetrant

Class Act Next Generation 2.5 to 5 gallons per 100 gallons

Surfactant Labels

Conclusion

• For the majority of conditions – difference

between surfactants or surfactant rates are very

subtle. Use the safest product.

• For some conditions – surfactant choice is

important and there are several good safe option

available.

• Surfactants are not silver bullets. Herbicides

will only work under the right conditions.