UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

                                                                        
                                                                        
             

                                                                        
                                              OFFICE OF

PREVENTION, PESTICIDES AND

                                                                        
                                                 TOXIC SUBSTANCES

                                                                        
                                                                        
                        

November 19, 2007

MEMORANDUM

SUBJECT:	Ecological Hazard and Environmental Risk Assessment Chapter for
the Organic Esters of Phosphoric Acid Reregistration Eligibility
Decision (RED) Document (Case No.: N/A)		

FROM:	Genevieve Angle, Biologist

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

TO:			Mark Hartman, Branch Chief

Diane Isbell, Team Leader

Regulatory Management Branch II

Antimicrobials Division (7510P)

THRU:                       Siroos Mostaghimi, Team Leader

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

Norman Cook, Branch Chief

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

Chemical Names					                                               PC
Codes	

Phosphoric acid, mono(2-ethylhexyl) ester                         			
111286	         Phosphoric acid, bis(2-ethylhexyl) ester, compd. with
2,2’-(cocoalkylimino) 

bis(ethanol)       									129079

Phosphoric acid, mono(2-ethylhexyl) ester, compds. with diethanolamine 

N-coco	 alkyl derivs. (1:1)								129080

Attached is the Ecological Hazard and Environmental Risk Assessment
Chapter for the Organic Esters of Phosphoric Acid RED Document.



ECOLOGICAL HAZARD AND ENVIRONMENTAL RISK ASSESSMENT CHAPTER FOR ORGANIC
ESTERS OF PHOSPHORIC ACID

Phosphoric acid, mono(2-ethylhexyl) ester;

Phosphoric acid, bis(2-ethylhexyl) ester, compd. with
2,2’-(cocoalkylimino) bis(ethanol);

Phosphoric acid, mono(2-ethylhexyl) ester, compds. with diethanolamine
N-coco alkyl derivs. (1:1)

PC Codes: 111286; 129079; 129080

CASE No.: N/A

11/19/2007

Genevieve Angle, Biologist

Antimicrobials Division

Office of Pesticide Programs

U.S. Environmental Protection Agency

1200 Pennsylvania Avenue, NW

Washington, DC 20460

Table of Contents

EXECUTIVE
SUMMARY………………………………………………………
………….3

  TOC \o "1-3" \u  I.       Ecological Toxicity Data	3

A.	Toxicity to Terrestrial Animals	3

1.	Birds, Acute and Subacute	3

2.	Mammals, Acute and Chronic	4

3.	Non-target Insect, Honeybees	4

B.	Toxicity to Aquatic Animals	4

1.	Freshwater Fish, Acute	4

2.	Freshwater Fish, Chronic	5

3.	Freshwater Invertebrates, Acute	5

4.	Freshwater Invertebrates, Chronic	6

5.	Estuarine and Marine Organisms	6

C.	Toxicity to Plants	6

II.	Risk Assessment and Risk Characterization	6

A.	Environmental Fate Assessment Summary	6

B.	Environmental Exposure and Ecological Risk Assessment	6

C.	Endangered Species Considerations	7

III.	Confirmatory Data Required	8

IV.	Label Hazard Statements for Terrestrial and Aquatic Organisms	8

V.	References	8

 EXECUTIVE SUMMARY

The organic esters of phosphoric acid act as fungicides, disinfectants,
bacteriostats and microbicides/microbistats.  They are used as materials
preservatives in carpets; epoxy flooring and tiles; vinyl products
including wall coverings, car tops, awnings, tarpaulins, tents, sails,
drapes, shower curtains, cubicle curtains, and film; plastic furniture;
polymeric laminates; polymer concrete; water, oil and solvent based
paints, stains and other coating systems used on interior and exterior
surfaces, machinery and equipment including heating, ventilating and air
conditioning systems; molded polymeric and polymer concrete bath tubs,
showers and bathroom sinks, countertops and accessories; various molded
polymer and polymer concrete products for general household, industrial,
commercial and healthcare use; natural and synthetic polymeric sealants,
adhesives and caulking compounds; textile and vinyl upholstery,
mattresses, mattress ticking and mattress covers; and air filters to be
used in furnaces, air conditioners, air purification devices,
automobiles and re-circulating air handling systems.

The Agency considers the registered uses of organic esters of phosphoric
acid ones which result in limited environmental exposure.  For these
types of scenarios the Agency performs ecological hazard and
environmental labeling assessments and requires the submission of three
ecological effects studies:  avian acute oral LD50, acute freshwater
fish LC50, and acute freshwater aquatic invertebrate EC50.

Although there are no ecotoxicity data on the organic esters of
phosphoric acid, if a spill of these organic esters were to occur in the
environment, it is likely that terrestrial and aquatic organisms would
be exposed to a mixture of organic esters of phosphoric acid, phosphoric
acid, and salts of phosphoric acid (e.g., calcium phosphate).  Further,
considering that there are ecotoxicity data available for phosphoric
acid, additional testing with the organic esters would not provide any
additional pertinent information and is not required.  There are
adequate data available to determine the labeling for the organic esters
by utilizing the data available for the mineral acid, phosphoric acid.

However, it should be noted that mineral acids such as phosphoric acid
pose a potential hazard to the aquatic environment not because of
inherent toxicity but instead due to their ability to change the pH of
receiving waters and create eutrophication.  The pH is an important
factor in the chemical and biological systems of natural waters.  In
addition, eutrophication from sudden additions of plant nutrients such
as phosphorus can lead to rapid algal and aquatic plant growth in water
bodies and cause oxygen shortages which can kill aquatic animals. 
Sufficient exposure to mineral acids to significantly change the pH and
cause eutrophication is harmful to aquatic species and such exposure
should be avoided whenever possible.

Ecological Toxicity Data

Toxicity to Terrestrial Animals

Birds, Acute and Sub-acute

For uses such as those listed above, an acute oral toxicity study using
the technical grade of the active ingredient (TGAI) is normally required
to establish the toxicity of these chemicals to birds. The preferred
test species is either mallard duck (a waterfowl) or northern bobwhite
quail (an upland game bird). No avian oral toxicity studies were found
in the Agency's files for these chemicals.  However, it has been
determined that an avian dietary study using phosphoric acid can be used
to satisfy this data requirement.  The results of this avian dietary
study are provided in Table 1 below.  No further avian testing is
required at this time.   

Table 1.  Subacute Oral (Dietary) Toxicity of Phosphoric Acid to Birds

Species	

Chemical,

% Active Ingredient

(a.i.)

Tested	

Endpoint

(ppm)	

Toxicity Category	

Satisfies Guidelines/

Comments	

Reference

(MRID or ACC No.)

Bobwhite quail

(Colinus virginianus)	Phosphoric Acid 48%	LC50 (diet) = >5620

NOAEC = 5620	Relatively nontoxic	Yes (core for formulated product)

-	8-day test duration

-	10 days of age	43909003



The results from this acceptable study indicate that phosphoric acid is
relatively non-toxic to avian species through subacute dietary exposure.

Mammals, Acute and Chronic

A summary of mammalian toxicity of organic esters of phosphoric acid is
presented in the “Evaluation of Toxicity Database for Reregistration
Eligibility Decision Document Disciplinary Chapter”.

Non-target Insect, Honeybees

Honeybee testing is not required for the currently registered uses of
organic esters of phosphoric acid. Honeybees should not be exposed to
organic esters of phosphoric acid because of the use patterns of this
pesticide. Therefore, the honeybee contact LD50 test is not required.

Toxicity to Aquatic Animals

Freshwater Fish, Acute

Freshwater fish acute toxicity studies using the TGAI are required to
establish the toxicity of these chemicals to fish. Data are generally
required for only one species for “indoor” uses. The preferred test
species are rainbow trout (a coldwater fish) or bluegill sunfish (a warm
water fish), although other test species identified in the OPPTS
Guideline (i.e., OPPTS 850.1075 (e)(4)(i)(A)) may also be used.  No
freshwater fish acute toxicity studies were found in the Agency’s
files for these chemicals. However, it has been determined that two
freshwater fish acute toxicity studies using phosphoric acid can be used
to satisfy this data requirement.  The results of these studies are
provided in Table 2 below.  No further freshwater fish acute testing is
required at this time. 

Table 2.  Acute Toxicity of Phosphoric Acid to Freshwater Fish

Species	

Chemical,

% Active Ingredient

(a.i.)

Tested	

Endpoint

(mg/L)	

Toxicity Category	

Satisfies Guidelines/

Comments	

Reference

(MRID or ACC No.)

Bluegill sunfish (Lepomis macrochirus)	Phosphoric Acid 48%	LC50 = 60
(43-72)

NOEC = 25

	Slightly toxic	Yes (core for formulated product)

-  96-hr test duration

-  static test system	43909005

Rainbow trout (Oncorhynchus mykiss)	Phosphoric Acid 48%	LC50 = 87
(74-123)

NOEC = 26	Slightly toxic	Yes (core for formulated product)

-  96-hr test duration

-  static test system	43909006



Freshwater acute toxicity tests indicate that phosphoric acid is
slightly toxic to freshwater fish on an acute basis.  These studies
fulfill the guideline requirement for freshwater fish species under
OPPTS 850.1075 (72-1a&b).

Freshwater Fish, Chronic

Early life stage testing in fish is not required for the currently
registered uses of organic esters of phosphoric acid.

Freshwater Invertebrates, Acute

A freshwater invertebrate acute toxicity test using the TGAI is required
to establish the toxicity of a pesticide to aquatic invertebrates. The
preferred test species is Daphnia magna. No acceptable acute freshwater
invertebrate studies were found in the Agency’s files for these
chemicals.  However, it has been determined that a freshwater
invertebrate study using phosphoric acid can be used to satisfy this
data requirement.  The results of this study are provided in Table 3
below.  No further freshwater invertebrate acute testing is required at
this time.   

Table 3.  Acute Toxicity of Phosphoric Acid to Freshwater Invertebrates

 

Species	

Chemical,

% Active Ingredient

(a.i.)

Tested	

Endpoint

(mg/L)	

Toxicity Category	

Satisfies Guidelines/

Comments	

Reference

(MRID or ACC No.)

Waterflea (Daphnia magna)	Phosphoric Acid 48%	EC50 = 105 (72-121)

NOEC = 25

	Relatively Nontoxic	Yes (core for formulated)

-	48-hr test duration

-	static test system	43909007



The results of this study indicate that phosphoric acid is relatively
nontoxic to freshwater invertebrates.  This study fulfills guideline
requirement OPPTS 850.1010 (72.2a).  

Freshwater Invertebrates, Chronic

Chronic freshwater invertebrate testing is not required for the
currently registered uses of organic esters of phosphoric acid.

Estuarine and Marine Organisms

Toxicity testing with estuarine and marine organisms is not required for
the currently registered uses of organic esters of phosphoric acid.

Toxicity to Plants

Toxicity testing with terrestrial and aquatic plants is not required for
the currently registered uses of organic esters of phosphoric acid.

II. Exposure and Risk to Nontarget Terrestrial Animals and Aquatic
Organisms

 Environmental Fate Assessment Summary

See section B.

 Environmental Exposure and Ecological Risk Assessment

The Agency considers the registered uses of organic esters of phosphoric
acid ones which result in limited environmental exposure.  For these
types of scenarios the Agency performs ecological hazard and
environmental labeling assessments and requires the submission of three
ecological effects studies:  avian acute oral LD50, acute freshwater
fish LC50, and acute freshwater aquatic invertebrate EC50.

Although there are no ecotoxicity data on the organic esters of
phosphoric acid, if a spill of these organic esters were to occur in the
environment, it is likely that terrestrial and aquatic organisms would
be exposed to a mixture of organic esters of phosphoric acid, phosphoric
acid, and salts of phosphoric acid (e.g., calcium phosphate).  Further,
considering that there are ecotoxicity data available for phosphoric
acid, additional testing with the organic esters would not provide any
additional pertinent information and is not required.  There are
adequate data available to determine the labeling for the organic esters
by utilizing the data available for the mineral acid, phosphoric acid.

However, it should be noted that mineral acids such as phosphoric acid
pose a potential hazard to the aquatic environment not because of
inherent toxicity but instead due to their ability to change the pH of
receiving waters and create eutrophication.  The pH is an important
factor in the chemical and biological systems of natural waters.  In
addition, eutrophication from sudden additions of plant nutrients such
as phosphorus can lead to rapid algal and aquatic plant growth in water
bodies and cause oxygen shortages which can kill aquatic animals. 
Sufficient exposure to mineral acids to significantly change the pH and
cause eutrophication is harmful to aquatic species and such exposure
should be avoided whenever possible.

 Endangered Species Considerations

Section 7 of the Endangered Species Act, 16 U.S.C. Section 1536(a)(2),
requires all federal agencies to consult with the National Marine
Fisheries Service (NMFS) for marine and andronomous listed species, or
the United States Fish and Wildlife Services (FWS) for listed wildlife
and freshwater organisms, if an “action” is proposed that may affect
listed species or their designated habitat. Each federal agency is
required under the Act to insure that any action they authorize, fund,
or carry out is not likely to jeopardize the continued existence of a
listed species or result in the destruction or adverse modification of
designated critical habitat. To jeopardize the continued existence of a
listed species means “to engage in an action that reasonably would be
expected, directly or indirectly, to reduce appreciably the likelihood
of both the survival and recovery of a listed species in the wild by
reducing the reproduction, numbers, or distribution of the species”.
50 C.F.R. 402.02

To facilitate compliance with the requirements of the Endangered Species
Act subsection (a)(2) the Environmental Protection Agency, Office of
Pesticide Programs has established procedures to evaluate whether a
proposed registration action may directly or indirectly reduce
appreciably, the likelihood of both the survival and recovery of a
listed species in the wild by reducing the reproduction, numbers, or
distribution of any listed species (U.S. EPA 2004). After the Agency’s
screening-level risk assessment is performed and any of the Agency’s
Listed Species LOC Criteria are exceeded for either direct or indirect
effects, a determination is made to identify if any listed or candidate
species may co-occur in the area of the proposed pesticide use. If
determined that listed or candidate species may be present in the
proposed use areas, further biological assessment is undertaken. The
extent to which listed species may be at risk then determines the need
for the development of a more comprehensive consultation package as
required by the Endangered Species Act.  

For certain use categories, the Agency assumes there will be minimal
environmental exposure, and only a minimal toxicity data set is required
(Overview of the Ecological Risk Assessment Process in the Office of
Pesticide Programs U.S. Environmental Protection Agency – Endangered
and Threatened Species Effects Determinations, 1/23/04, Appendix A,
Section IIB, pg.81). The organic esters of phosphoric acid are
registered for use patterns that are expected to have little to no
environmental exposure.  Chemicals in these categories do not undergo a
full screening-level risk assessment.  

The organic esters of phosphoric acid are mostly used indoors as
fungicides, disinfectants, bacteriostats and microbicides/microbistats
for materials preservation. This preliminary analysis does not indicate
whether there is a potential for organic esters of phosphoric acid uses
to overlap with listed species and whether a more refined assessment is
warranted, to include direct, indirect, and habitat effects. The more
refined assessment should involve clear delineation of the action area
associated with proposed use of organic esters of phosphoric acid and
best available information on the temporal and spatial co-location of
listed species with respect to the action area. This analysis has not
been conducted for this assessment. The Agency expects minimal
environmental exposure from the registered use patterns; however an
endangered species effect determination will not be made at this time.

 Confirmatory Data Required

At this time, no additional data are required for the current registered
uses of organic esters of phosphoric acid. 	

IV.   Label Hazard Statements for Terrestrial and Aquatic Organisms

Organic esters of phosphoric acid labels must state:

	“Do not discharge effluent containing this product into lakes,
streams, ponds, estuaries, oceans, or other waters unless in accordance
with the requirements of a National Pollutant Discharge Elimination
System (NPDES) permit and the permitting authorities are notified in
writing prior to discharge. Do not discharge effluent containing this
product to sewer systems without previously notifying the local sewage
treatment plant authority. For guidance contact your State Water Board
or Regional Office of the EPA.”

References

43909003.  Palmer, S.J. and J.B. Beavers.  1995.  Divosan X-Tend: A
Dietary LC50 Study with the Northern Bobwhite; ID No. 425-101; Prepared
by Wildlife International Ltd. for Diversey Corporation, Livonia,
Michigan.

43909005.  Zelinka, E.A., K.R. Drottar and J.P. Swigert.  1996.  Divosan
X-Tend: A 96-Hour Static Acute Toxicity Test with the Bluegill (Lepomis
macrochirus); ID No. 425A-102; Prepared by Wildlife International Ltd.
for Diversey Corporation, Livonia, Michigan.

43909006.  Zelinka, E.A., K.R. Drottar and J.P. Swigert.  1996.  Divosan
X-Tend: A 96-Hour Static Acute Toxicity Test with the Rainbow Trout
(Oncorhynchus mykiss); ID No. 425A-101; Prepared by Wildlife
International Ltd. for Diversey Corporation, Livonia, Michigan.

43909007.  Drottar, K.R. and J.P. Swigert.  1995.  Divosan X-Tend: A
48-Hour Static Acute Toxicity Test with the Cladoceran (Daphnia magna);
ID No. 425A-103; Prepared by Wildlife International Ltd. for Diversey
Corporation, Livonia, Michigan.

	

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