UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON D.C., 20460 

OFFICE OF 

PREVENTION, PESTICIDES AND 

TOXIC SUBSTANCES

PC Code: 128940 

Chemical: Flutriafol 

DP Barcode: D356830 

January 20, 2010 

MEMORANDUM 

SUBJECT: Revised Baseline Ecological Risk Assessment for the Registration of 

Flutriafol

FROM: Stephen Carey, Biologist 

 Stephanie Syslo, Environmental Scientist/RAPL 

 Mary Frankenberry, Senior Statistician 

 James Hetrick, Ph.D., Senior Advisor 

 Environmental Risk Branch 3 

THRU: Dana Spatz, Chief 

 Environmental Risk Branch 3 

 Environmental Fate and Effects Division (7507P) 

 

TO: Mary Waller, Risk Manager 

 Tamue Gibson, Risk Manager Reviewer 

 Registration Division (7505P) 

The Environmental Fate and Effects Division (EFED) has revised the environmental fate and 

ecological risk assessment for flutriafol (version dated December 12, 2008) in support of the new 

active ingredient, flutriafol (CAS Registry Number: 76674-21-0) and its End Use Product – 

TOPGUARDTM - a soluble concentrate containing 11.8% active ingredient [EPA Reg. No. 

67760-TL], for use to control fungal diseases on apples and soybeans. Based on communications 

with the Registration Division, the maximum number of applications to apples that was assessed 

was decreased from six to four; EECs associated with the apple use were remodeled accordingly 

and new Risk Quotients (RQs) were calculated. Also, environmental fate and ecotoxicology 

studies submitted by the registrant since the original 2008 assessment have been reviewed and 

the results incorporated into the revised document. Conclusions regarding the environmental 

fate, ecological effects, and ecological risks associated with the proposed uses in agricultural 

areas can be found in the Executive Summary of the attached document. 
The combination of field observations of leaching from registrant-submitted studies and EFED 

modeling predictions indicate a potential for flutriafol to contaminate ground water. Results 

from non-guideline field dissipation studies showed that following multiple applications over a 

number of years, flutriafol residues were found in the soil to the maximum depth sampled. 

PRZM modeling conducted by EFED predicted that the dominant route of dissipation for 

flutriafol is leaching below the root zone. 

In addition, the Draft Assessment Report on flutriafol prepared by the UK for submission to the 

European Commission to enable a decision to be made on the inclusion of flutriafol on Annex I 

of the Directive 91/414/EEC (draft dated May 2006: Flutriafol_DAR_01_Vol-1_public .pdf) 

predicted annual average concentrations of flutriafol in leachate leaving the top 1 m soil layers 

would exceed 0.1 μg/L 80% of the time (peak concentration of 4.259 μg/L as modeled using 

FOCUS model). 

Since multiple ground water models predict that flutriafol will leach out of the surface layer of 

soil and since no field data quantifying the maximum depth of leaching under actual use 

conditions have been provided to the Agency, EFED is recommending that a Small Scale 

Prospective Ground Water Monitoring study (EPA Guideline 835.7100) be conducted to 

evaluate the potential for flutriafol to contaminate ground water 

Considering the ecotoxicity data along with exposure estimates, EFED concludes that for 

terrestrial species, there is an indication of acute and chronic risks to birds, reptiles, terrestrialphase amphibians and mammals when exposed to flutriafol. 

There is no indication of risk to freshwater or estuarine/marine species through acute or chronic 

exposure to the active ingredient. Risk is minimal for listed terrestrial monocots and dicots and 

listed aquatic vascular and non-vascular plant species. Precautionary labeling for honeybees is 

not required since flutriafol and its formulated product are practically nontoxic to bees. 

Ecotoxicity profile 

Levels of concern were exceeded for listed birds (acute RQs ≤ 0.25; chronic RQs ≤ 2.21), 

terrestrial-phase amphibians (based on surrogate species), reptiles (based on surrogate species), 

and mammals (acute RQs ≤ 0.43; chronic RQs ≤ 1.83). Therefore, there is potential for indirect 

effects to all taxa dependant on birds, mammals, reptiles, and terrestrial-phase amphibians for 

habitat, feeding, cover requirements, for survival, growth, or reproduction, and as pollinators, 

seed dispersers, or burrowers. Direct effects LOCs were not exceeded for birds and mammals 

feeding on large insects and seeds, freshwater and estuarine/marine fish and invertebrates, 

aquatic-phase amphibians (based on surrogate species), terrestrial monocots and dicots, and 

aquatic vascular and non-vascular plants. 

Acute toxicity data for aquatic species indicate that technical grade flutriafol is slightly toxic to 

freshwater species and no more than slightly toxicity to estuarine/marine species. Chronic data 

with the technical grade active ingredient (TGAI) for estuarine/marine animals are not available 

and the toxicity to these taxa is estimated by an acute to chronic ratio approach. Based on acute 

toxicity data, flutriafol is slightly toxic to practically non-toxic to upland game birds and 

2
waterfowl via oral and dietary routes. There are no acute oral toxicity data with a passerine bird; 

therefore, the toxicity to these birds is uncertain. Chronic studies with flutriafol indicate 

numerous reproductive effects to upland game birds and waterfowl at levels as low as 95 mg 

ai/kg-diet. Flutriafol technical is classified as moderately to slightly toxic to mammals and 

reproductive effects were observed as a result of chronic exposure as low as 1000 ppm (88.7 mg 

ai/kg-diet/day in parental rat males). 

Toxicity data for freshwater fish and invertebrates, mammals, and terrestrial and aquatic plants 

with the formulated product, Flutriafol 125 g/L SC, are available. A comparison of the available 

formulated product (TOPGUARD fungicide) and technical grade toxicity data shows the 

formulated product, when results are expressed in terms of the active ingredient, is 

approximately 30 to 50-fold more toxic than technical grade flutriafol in an aquatic environment. 

Formulation blank data suggest the greater toxicity of the formulated product is not due to 

synergistic effects of the combination of the active ingredient and inerts, but is due to the toxicity 

of one or more of the inert ingredients. A change in the inert ingredients for TOPGUARD could 

mitigate the toxicity to aquatic organisms and plants. 

Data Gaps 

The fate laboratory data set for flutriafol is mostly complete for the parent compound and is 

adequate for the proposed use pattern. However, EFED is recommending that a Small Scale 

Prospective Ground Water Monitoring study (EPA Guideline 835.7100) be conducted to 

evaluate the potential for flutriafol to contaminate ground water. Environmental chemistry 

methods used to generate data associated with this study must include results of a successful 

confirmatory method trial by an independent laboratory. Test standards and procedures for 

independent laboratory validation are available as addenda to the guideline for this test 

requirement. Agency approval of a protocol is necessary prior to initiation of the study. 

The ecological data set for flutriafol is mostly complete except for passerine birds. No toxicity 

data are available for the degradation products of flutriafol and they are uncertain; however, in 

the drinking water assessment for flutriafol, there was no concern about residues less than 10% 

of parent equivalents. In addition, the structure analysis relationship model (ECOSAR) 

estimated the toxicity of the degradates, based on individual chemical structures, to be less toxic 

to aquatic animals than the parent compound. Therefore, concern about the degradates in the 

environment, from a toxicological perspective, is minimal. An exception to this is the minor 

degradate 1,2,4-triazole. This degradate is a common degradate to other conazole fungicides and 

its fate properties and toxicity will be addressed by the Agency in a separate assessment. 

No acute oral toxicity data with a passerine bird are available. The risk to passerine birds 

exposed to flutriafol application is uncertain. A risk assessment for acute exposure to passerine 

birds is needed based on the use pattern of flutriafol in agricultural fields. 

3
Table A.1. identifies the status of environmental fate and transport study requirements and 

Table A.2. identifies the status of ecological effects study requirements. 

Table A.1. Environmental Fate and Transport Data Requirements for Flutriafol and its 

Formulated Product 

Study Type Study 

Classification

Are 

Additional 

Data Needed 

at This Time? 

MRID 

Hydrolysis (161-1) Acceptable No 47090416 

Aqueous Photolysis (161-2) Acceptable 47090417 

supplemental 

No 

47090418 

Soil Photolysis (161-3) supplemental No 47418401 

Supplemental 47090421

Supplemental 47090422 

Aerobic Soil Metabolism 

(162-1) 

Supplemental 

No

47090423 

Anaerobic Soil / Aquatic Metabolism 

(162-2, 162-3) 

Acceptable No 47090424 

Aerobic Aquatic Metabolism 

(162-4)

Supplemental No 47090419 

Supplemental 47090425 

Supplemental 47090426 

Supplemental 47090427 

Supplemental 

No 

47090428 

Adsorption / Desorption 

(163-1) 

Ancillary No 47345401 

Bioaccumulation in Fish (165-4) Acceptable No 47090437 

Supplemental 

47090429 

Supplemental 47090431 

Supplemental 47090432 

Supplemental 47115502 

Supplemental 47090433 

Supplemental 47090434 

Terrestrial Field Dissipation (164-1) 

Supplemental

No 

47090435 

4
Table A.1. Environmental Fate and Transport Data Requirements for Flutriafol and its 

Formulated Product 

Small scale Prospective Ground Water 

Monitoring 

No data Yes No data 

Non-Guideline – Calculation of first 

order DT50 and DT90 values by nonlinear regression analysis. 

Supplemental not required 47090436 

Table A.2. Ecological Toxicity Data Requirements for Flutriafol and its Formulation Product

OPPTS Are more data needed?

Guideline # Data Requirement MRID # Classification

Flutriafol 

850.2100 

Avian acute oral LD50

(bobwhite quail) 

(mallard duck) 

(red-legged partridge) 

(passerine bird)

47471301 

47090318 

47090319 

No data 

Acceptable 

Acceptable 

Supplemental 1 

No data 

No 

No 

No 

Yes

850.2200 

Avian subacute dietary LC50

(bobwhite quail) 

(mallard duck)

47090321 

47090320 

Acceptable 

Acceptable 

No 

No 

850.2300 

Avian reproduction 

(bobwhite quail) 

(mallard duck) 

47090323 

47090322 

Supplemental 2

Acceptable 

No 

No 

850.1075 

Freshwater fish acute LC50

(bluegill sunfish) 

(rainbow trout) 

47090310 

47090311 

Acceptable 

Acceptable 

No 

No 

850.1010 Freshwater invertebrate acute EC50

(daphnia) 47090304 Acceptable No 

850.1075 Estuarine/marine fish acute LC50

(sheepshead minnow) 47090308 Acceptable No 

850.1025 and 

850.1035 

Estuarine/marine invertebrate acute EC50

(eastern oyster) 

(mysid)

47090306 

47090307 

Acceptable 

Acceptable 

No 

No 

850.1400 Freshwater fish early life stage 

(fathead minnow) 47090317 Acceptable No 

850.1300 Freshwater invertebrate life cycle 

(daphnia)

47090314 

47090315 

Acceptable 

Supplemental 3 No 

850.1400 Estuarine/marine fish early life stage 

(sheepshead minnow) No data Not applicable No 

850.1350 Estuarine/marine invertebrate 

life cycle (mysid) No data Not applicable No 

850.1500 Freshwater fish full life cycle No data Not applicable No 

870.1100 Acute mammalian oral LD50 (rat or mice) 47090335 Acceptable No 

870.3800 Mammalian Reproduction (rat) 47090351 Acceptable No 

850.4100 Seedling Emergence – Tier I 47090328 Acceptable No 

850.4150 Vegetative Vigor - Tier I 47090329 Acceptable No 

850.4225 Seedling Emergence – Tier II No data Not required No 

850.4250 Vegetative Vigor - Tier II 47689801 Acceptable No 

5
6

850.5400 

Aquatic plant algae 

(green algae) 

(blue-green cyanobacteria) 

(freshwater diatom) 

(estuarine/marine diatom) 

47090333 

47090334 

47090332 

47090331 

Supplemental4

Supplemental4

Supplemental4

Supplemental4

No 

No 

No 

No 

850.4400 Aquatic plant acute EC50

(duckweed) 47090330 Supplemental 4 No 

850.3020 Acute honey bee contact LD50 47090326 Acceptable No 

Non-guideline Acute honey bee oral LD50 47090326 Supplemental No 

850.3030 Honey Bee Residue on Foliage No data Not applicable No 

850.3040 Honey Bee Field Testing for Pollinator No data Not applicable No 

1

 >5% mortality occurred during acclimation 

2

 Significant effects were observed at all treatment levels, a NOAEC could not be determined. The study needs to establish an NOAEC with 

lower concentrations. 

3

 Only the test solutions of the biologically relevant levels were analyzed in this study. Guideline requires all treatment levels including the 

biologically relevant levels be analyzed 4 Data were not available to establish a dose-response curve for the formulation inerts.