Document ID: EPA-HQ-OPP-2008-0148-0006
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2008-09-15T04:00Z

Guideline Number: (OPPTS Guideline Currently Being Developed)

Chronic, Whole Sediment  Invertebrate Toxicity

Rationale for Requiring the Data

According to 40CFR Part 158, the use patterns, physical-chemical
properties and available toxicity data of flutolanil qualify it for a
conditionally-required chronic sediment toxicity test.  Specifically,
the anaerobic metabolism half life of flutolanil is > 13 years (far
exceeding the 10 days criterion for a chronic sediment test).  Further,
both the log KOW (3.7) and KOC (up to 1300) exceed thresholds for
chronic sediment testing (3.0 and 1000, respectively).  Finally, there
is concern over estuarine/marine benthic invertebrates due to their
demonstrated high sensitivity to flutolanil in water column tests (most
sensitive aquatic species tested; EC50 and NOAECs of 130 and 11.3 ppb,
respectively).  Therefore, results of the recommended chronic sediment
toxicity testing could reasonably be expected to have a significant
impact on the ecological risk assessment of flutolanil.  Currently, no
sediment toxicity data have been submitted for flutolanil.

Practical Utility of the Data

How will the data be used?   

Of all of the aquatic toxicity studies, estuarine/marine shrimp were by
far the most sensitive (by 1-2 orders of magnitude).  The availability
of chronic sediment toxicity data for estuarine species will allow the
Agency to evaluate risks to this group of aquatic organisms that inhabit
sediments.  The toxicity data will be used in conjunction with predicted
concentrations of flutolanil in sediment and sediment pore water to
determine the potential risks to benthic invertebrates. Chronic sediment
toxicity data for marine/estuarine crustaceans would allow the Agency to
refine the screening level risk assessment for registration review and
any future new uses proposed for this compound.  By refining the
assessment, the Agency would be able to determine more precisely the
appropriate mitigation measures for flutolanil, should potential risks
be found.

How could the data impact the Agency’s future decision-making?

If the data indicates that flutolanil poses significant risks to
sediment invertebrates inhabiting marine/estuarine water bodies, the
Agency may explore additional decision options to minimize the risk of
flutolanil marine/estuarine sediment-dwelling invertebrates. 

The lack of these data will limit the flexibility the Agency and
registrants have in coming into compliance with the Endangered Species
Act and could result in use restrictions for flutolanil that may be
unnecessary.  

Guideline Number:  Non-Guideline Study

Study Title: Measurement of Octanol-Air Partition Coefficient (KOA) 

Rationale for Requiring the Data

Recent peer-reviewed studies in the scientific literature indicate that
KOA is an important factor in assessing the potential of organic
chemicals to bioaccumulate and biomagnify in terrestrial food chains
(e.g., Armitage and Gobas, 2007; Kelly et al., 2007; Czub and McLachlan,
2004; Kelly and Gobas, 2003; Sharp and Mackay, 2000; McLachlan, 1996). 
No measured data on the KOA of flutolanil were found.  However,
model-predicted log KOA for flutolanil is very high (10.6) based on the
Agency’s EPIsuite program, ver. 3.20.  In absence of a measured KOA
value, a model-estimated value has been used in this problem
formulation. Therefore, measured data on KOA are being requested in
order to confirm model-predicted values of KOA, which may be uncertain.
Given the extremely high model-derived estimates of log KOA (10.6), it
is possible that it may overestimate KOA compared to measured values. 
As a result, the potential bioaccumulation of flutolanil may be
overestimated without a measured value of KOA.  This measurement is very
important in evaluating the potential for flutolanil to bioaccumulate in
terrestrial food chains.

How will the data be used?    

Measured data on KOA would be used in combination with available
bioaccumulation models to estimate the potential bioaccumulation of
flutolanil in terrestrial food webs.  If predicted bioaccumulation is
found to pose risks to terrestrial organisms, additional information
(e.g., monitoring studies, terrestrial bioaccumulation studies, and/or
mitigation measures) might be requested. 

How could the data impact the Agency’s future decision-making?

Measured data on KOA could affect the Agency’s future decision-making
in various ways.  If predicted bioaccumulation in terrestrial food webs
is found to be a concern to the Agency using model-derived values of
KOA, then measured data could either confirm or refute these
predictions.  In this case, requests for additional information and/or
risk mitigation measures could be highly sensitive to data on KOA. 
Since existing terrestrial bioaccumulation models largely depend on KOA,
values, such information would be extremely important for addressing
uncertainty in the forthcoming risk assessment.  

Guideline Number: 850.4100

Study Title: Seedling emergence, Tier I

Guideline Number: 850.4150

Study Title: Vegetative vigor, Tier I

  

Rationale for Requiring the Data

Currently, no data are available on the toxicity of flutolanil to
terrestrial plants.  Screening (Tier I) studies are being recommended to
address uncertainty regarding the potential impacts of flutolanil on
non-target terrestrial plants.  Such studies are required as outlined in
40CFR Part 158 and are required in order to assess risks associated with
flutolanil uses on terrestrial plants.  These results are also needed
for endangered species assessment for flutolanil.

Practical Utility of the Data

How will the data be used?  

Data from Tier I terrestrial plant toxicity studies will be used to
estimate potential risks to non-target plants associated with uses of
flutolanil.  The data will reduce uncertainties associated with the
current risk assessment for terrestrial plants and will improve our
understanding of the potential effects of flutolanil on plants.

How could the data impact the Agency’s future decision-making?

Because plants form the basis of most habitats and significantly
contribute to overall environmental quality, a solid understanding of
the potential risks to terrestrial plants is essential for sound
environmental management.  Without terrestrial plant growth data for
flutolanil, the Agency cannot determine the levels of flutolanil that
result in effects to terrestrial plants.  If the data indicates that
registered flutolanil usage may pose a risk of adverse effects to
non-target terrestrial plants above the Agency Level of Concern, the
Agency may explore decision options to mitigate this risk.  The lack of
these data will limit the flexibility the Agency and registrants have in
coming into compliance with the Endangered Species Act, and could result
in use restrictions for flutolanil which may otherwise be avoided, or
which are unnecessarily severe.

Guideline Number: 835-4200

Study Title: Anaerobic Soil Metabolism 

Guideline Number:  (No Guideline Available)

Study Title:   Environmental Chemical Methods (ECM)/Independent
Laboratory Validation (ILV) 

Rationale for Requiring the Environmental Fate Studies Performed in the
Laboratory

EPA requires a series of individual laboratory studies to assess the
behavior and fate of a pesticide in the environment. Controlled
environmental fate and transport laboratory studies are used to
determine the persistence and mobility potential of a pesticide active
ingredient and its major degradates. The studies offer information on
how, or by what mechanism, the pesticide degrades or dissipates, the
rate at which it degrades or dissipates, where it goes, and what
transformation products are formed. Data from these studies are used as
inputs to exposure models. These models estimate the expected
environmental concentrations of the pesticide and its degradates under
various environmental and use conditions. 

Metabolism studies include anaerobic soil metabolism. The soil microbial
metabolism study determines the persistence of the pesticide when it
interacts with soil microorganisms under anaerobic conditions. The study
also identifies the significant degradates that result from biological
degradation. Currently no acceptable studies have been submitted.

The ECM are the analytical methods that are used to generate data
associated with terrestrial field dissipation study (835.6100), aquatic
dissipation study (835.6200), forestry dissipation (835.6300), ground
water monitoring (835.7100), and aquatic non-target organism field
dissipation (850.1950) studies.  The ECM must include results of a
successful confirmation method trial by and independent laboratory
(ILV).  Currently no acceptable studies have been submitted. 

Practical Utility of the Data

How will the data be used?

The anaerobic soil metabolism study would facilitate a better
understanding of flutolanil’s degradation under anaerobic
(oxygen-free) conditions in the laboratory.  In order to calculate
EEC’s in PRZM and assess the ecological risk and the drinking water
risk, anaerobic soil data are needed.

The Environmental Chemical Methods (ECM)/Independent Laboratory
Validation (ILV) studies would allow the Agency to use the data with
confidence in the terrestrial dissipation, aquatic dissipation, and
aquatic non-target organism field accumulation studies as well as assess
the ecological risk.

How could the data change the Agency’s decision, or impact the
Agency’s future decision-making?  

If data indicate that flutolanil degrades slowly in the Anaerobic Soil,
then persistence may be a public health risk of concern and additional
use precautions and/or restrictions may be necessary.   Data from the
Environmental Chemical Methods (ECM)/Independent Laboratory Validation
(ILV) studies are very important in evaluating the validity of the
terrestrial dissipation, aquatic dissipation, and aquatic non-target
organism field accumulation studies as well as the risk assessment.

Flutolanil (Confirmatory Data Call-In)

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