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FIFRA SCIENTIFIC ADVISORY PANEL (SAP) OPEN MEETING March 13 - 16, 2001
March 8, 2001
FIFRA SAP WEB SITE: https://www.epa.gov/scipoly/sap/
OPP Docket Telephone: (703) 305-5805
TUESDAY, MARCH 13, 2001
HILTON HOTEL CRYSTAL CITY
2399 JEFFERSON DAVIS HIGHWAY
ARLINGTON, VIRGINIA 22202
703-418-6800
- 8:30 AM Introduction - Ronald J. Kendall, Ph.D. (FIFRA SAP Chair)
- 8:35 AM Administrative Procedures by Designated Federal Official - Mr. Paul Lewis
- 8:40 AM Identification of Panel Members - Ronald J. Kendall, Ph.D. (FIFRA SAP Chair)
- 8:50 AM Welcome - Steven K. Galson, M.D. M.P.H. (Director, Office of Science Coordination and Policy, Office of Prevention, Pesticides and Toxic Substances, EPA)
- 9:00 AM Introductory Remarks - Ms. Marcia E. Mulkey (Director, Office of Pesticide Programs, Office of Prevention, Pesticides and Toxic Substances, EPA)
- 9:10 AM Introduction, Goals and Objectives - Ingrid Sunzenauer, M.S.
(Office of Pesticide Programs, EPA)
A Probabilistic Model to Assess Acute Lethal Risks to Birds
- 9:30 AM Introduction - Edward Fite, M.S. (Office of Pesticide Programs, EPA)
- 9:45 AM BREAK
- 10:00 AM Overview of EPA, Office of Pesticide Programs' Pilot Avian Risk Model - Timothy Barry, ScD. (Office of Economy and Environment, EPA)
- 11:15 AM A Probabilistic Model and Process to Assess Acute Lethal Risks to Birds: Assessment Example - Edward Odenkirchen, Ph.D. (Office of Pesticide Programs, EPA) and Edward Fite, M.S. (Office of Pesticide Programs, EPA)
- 12:30 PM LUNCH
- 1:30 PM Risk Characterization and Next Steps - Edward Fite, M.S. (Office of Pesticide Programs, EPA)
- 2:00 PM Public Comments
Bill Williams, Ph.D. on behalf of Kennedy Jenks Consultants
David Fischer, Ph.D. on behalf of Bayer
- 3:30 PM Introduction to Questions - Edward Fite, M.S. (Office of Pesticide Programs, EPA)
- 3:40 PM BREAK
- 3:55 PM Panel Discussion
Question 1 1. Focal Species Selection Goals: The goals for selection of bird species serving as the focus of the risk assessment were to
(1) advance the assessment beyond consideration of "generic" bird types so as to consider appropriate biological conditions associated with the treated environments, and (2) identify the types of species potentially at greatest risk from ChemX exposure at the corn and alfalfa use sites identified above.
Under the current EFED status of probabilistic risk assessment development, the use of focal species in an assessment is limited. The likely lack of species-specific toxicity data engenders considerable uncertainty regarding the prediction of the magnitude of mortality in any single bird species. Rather, the use of focal species is targeted to represent a myriad of potential species of similar biological/behavioral characteristics, yet retain some specificity as to the type of organisms using a treated area.
- What is the Panel's opinion regarding this approach?
- What are the Panel's recommendations regarding alternative approaches that should be investigated?
- Drawing upon your experiences and knowledge of avian foraging strategies,
habitat use, and other interactions with the agroenvironments incorporated into
the assessment, what recommendations can the Panel make for alternative or additional
focal species for the crop/region combinations investigated in the assessment?
Lead Discussants: Louis. Best, Ph.D. and Christian Grue, Ph.D.
- 3:30 PM BREAK
- 3:45 PM Panel Discussion (continued) Questions 2-3 2. Frequency
of Birds in Treated Fields use in the Model: EFED recognizes that additional research
on quantifying exposure of bird species in agroenvironments will be critical to
the advancement of the probabilistic risk assessment approach. At this juncture,
EFED is mindful of the severe limits of existing avian census data for establishing
such exposure estimates. The present method for considering the avian census data
has been designed not to over represent the census data to the point that sightings
of birds on or off a treated field is considered commensurate with proportional
feeding on and off the field in a given day. Instead, the risk assessment uses
the data to determine the likelihood that a bird will be on a treated field in
a given time step, based on past field study history of sightings for that species.
- What are the Panel's thoughts regarding the use of avian census data in the model and was it used appropriately?
- What are the Panel's suggestions regarding alternative approaches to using the data? Please discuss any advantages and disadvantages to these alternative approaches.
Lead Discussants: Pierre Mineau, Ph.D. and Louis Best, Ph.D.
3. Frequency of Birds in Treated Fields, Setting Parameters: EFED elected to establish minimally biased truncated exponential distributions for this parameter for each focal species.
- Upon looking at the available field study data (see spreadsheets included in SAP package), what are the Panel's thoughts on these selections?
- What alternative approaches for these distributions would be appropriate for the data sets available?
Lead Discussants: Steven Heeringa, Ph.D., Elizabenth Halloran, M.D. and Phil Dixon, Ph.D.
- 5:30 PM ADJOURNMENT
HILTON HOTEL CRYSTAL CITY
2399 JEFFERSON DAVIS HIGHWAY
ARLINGTON, VIRGINIA 22202
703-418-6800
- 8:30 AM Introduction - Stephen M. Roberts, Ph.D. (FIFRA SAP Session Chair)
- 8:35 AM Administrative Procedures by Designated Federal Official - Mr. Paul Lewis
- 8:40 AM Identification of Panel Members - Stephen M. Roberts, Ph.D. (FIFRA SAP Session Chair)
- 8:50 AM Overview of Aquatic Assessment - Kathryn Gallagher, Ph.D. (Office of Pesticide Programs, EPA)
- 9:20 AM Overview of Aquatic Risk Assessment Model - Tim Barry, Sc.D. (Office of Economy and Environment, EPA)
- 10:15 AM BREAK
- 10:30 AM Aquatic Exposure Assessment - James Lin, Ph.D. (Office of Pesticide Programs, EPA)
- 11:15 AM Aquatic Effects Assessment: Methods and Approach - Les Touart, Ph.D. (Office of Pesticide Programs, EPA)
- 12:00 PM Risk Characterization and Next Steps - Kathryn Gallagher, Ph.D. (Office of Pesticide Programs, EPA)
- 12:30 PM LUNCH
- 1:30 PM Public Comments Iain Kelly, Ph.D. on behalf of Aventis Paul Hendley, Ph.D. on behalf of Syngenta
- 3:00 PM Overview of EPA Questions - Kathryn Gallagher, Ph.D. (Office of Pesticide Programs, EPA)
- 3:05 PM Panel Discussion
Question 1
1. Exposure Model Input Parameter Variability. In addressing the regional effects to the farm pond, we have used the exposure model matrix by looking at the combination of 3 pHs, 3 field-to-pond size ratios, and 2 soil aerobic metabolism rates, without changing the meteorological data. We are currently pursuing development of an exposure model to include the following parameters as variable inputs into PRZM/EXAMS: field/pond size, Kd, soil aerobic metabolism, application date, pond depth, and pH. What other parameters should be considered as variable distributions? Would the Panel please list other recommendations or suggestions for refining this approach, considering our purpose of PRA?
Lead Discussants: Kirk Hatfield, Ph.D., Chad Jafvert, Ph.D. and Thomas LaPoint, Ph.D.
- 3:30 PM BREAK
- 3:45 PM Panel Discussion (continued)
Questions 2-4
2. Exposure Distribution Profile Selection. The exposure component of the aquatic risk assessment model uses 36 year rainfall data to generate 36 annual maxima for exposure concentrations. Two approaches were employed in establishing an exposure distribution profile: a theoretical fitted distribution using Monte Carlo analysis and an empirical distribution using a bootstrap method. Both methods performed similarly except in the tails of the distributions. The empirical distribution is preferred due to its objectivity and speed of calculation. What should the criteria be for choosing between theoretical and empirical methods?
Lead Discussants: Phil Dixon, Ph.D., Thomas LaPoint, Ph.D. and George Cobb, Ph.D.
3. Interspecies Variability. In developing a sensitivity curve for freshwater fish with the available data, species' data were combined into their respective families. This was done because all families except salmonids had a single representative species, whereas, salmonids had four representatives. The aim was not to skew the sensitivity data by the over-representation with salmonids. The geometric mean of the multiple species and/or multiple tests with the same species was used in establishing points along this curve. What does the Panel think of this approach? Please provide alternative recommendations, if any, for dealing with limited data sets.
Lead Discussants: Paul Eslinger, Ph.D., Michael Newman, Ph.D. and George Cobb, Ph.D.4. Effects Input Distribution. The extrapolation of fish sensitivities used a lognormal distribution of toxicity (LC50s) and a normal distribution of the dose-response slopes. What does the Panel think of this approach and which other approaches could have been used? Lead Discussants: Michael Newman, Ph.D. Elizabeth Halloran, MD. and Christopher Portier, Ph.D.
- 5:15 PM ADJOURNMENT
FRIDAY, MARCH 16, 2001
HILTON HOTEL CRYSTAL CITY
2399 JEFFERSON DAVIS HIGHWAY
ARLINGTON, VIRGINIA 22202
703-418-6800 - 8:30 AM Introduction - Stephen M. Roberts, Ph.D. (FIFRA SAP Session Chair)
- 8:35 AM Administrative Procedures by Designated Federal Official - Mr. Paul Lewis
- 8:35 AM Review from previous day's meeting - Kathryn Gallagher, Ph.D. (Office of Pesticide Programs, EPA)
- 8:45 AM Panel Discussion (continued)
Questions 5-6
5. Extrapolation with Limited Data. Since only one acceptable toxicity test was available for an aquatic invertebrate, an extrapolation using toxicity profiles of other compounds in the same pesticide family to determine the average sensitivity of the tested species and extrapolate a species sensitivity distribution was employed. What does the Panel think of this approach? What are the Panel members opinions on alternative approaches that may be used for establishing a sensitivity profile across diverse invertebrate taxa when one or a very few tests are available?Lead Discussants: Peter Delorme, Ph.D. and Pierre Mineau, Ph.D.
6. Taxa Aggregation. Freshwater taxa were separated from marine taxa in this case study. Since the marine data sets were limited to a single test species, toxicity profiles for that species were used in the assessment and no sensitivity distribution across taxa performed. Data from other related pesticides for marine species were also not available as in the case for freshwater invertebrate taxa. What is the Panel's opinion of separating toxicity data from marine organisms from data on freshwater organisms for purposes of establishing sensitivity profiles? Would the Panel please provide an alternate recommendation, if it has one?
Lead Discussants: Michael Newman, Ph.D. and Thomas LaPoint, Ph.D.
- 10:15 AM BREAK
- 10:30 AM Panel Discussion (continued) Questions 7-8
7. Chronic Assessment. Available chronic data were limited and, therefore, fewer scenarios were considered sufficient to cover the range of outcomes. An exceedence probability approach was taken to evaluate the potential of chronic effects. What alternative approaches to evaluating chronic effects could have been taken?
Lead Discussants: William Adams, Ph.D., and Thomas LaPoint, Ph.D.
8. Estimation of Species Sensitivity. In this case study, probabilistic assessments were performed for specific species (e.g., bluegill sunfish and rainbow trout) and for extrapolated species (e.g., 5th percentile sensitive and 50th percentile sensitive). What is the Panel's view on the adequacy of this approach? Lead Discussants: William Adams, Ph.D. Thomas LaPoint, Ph.D. and Paul Eslinger, Ph.D.
- 12:00 PM LUNCH
- 1:00 PM Panel Discussion (continued)
Questions 9-10
9. Model Parameterization. Four parameters were varied in each Monte Carlo analysis performed for a specific organism associated with a given scenario: the magnitude and shape of the exposure curve and the slope and intercept of the dose response curve. What parameters does the Panel believe should be varied in the lower tiers of a probabilistic risk assessment? For the case study, toxicity data from standard toxicity test protocols with a narrow range of animal age and size and test condition were used. What does the Panel believe with respect to the expression of generic effects ignoring size, age, feeding, respiration rate, etc.? Is the generic prediction approach sufficient or should the model include consideration of variations in these parameters?
Lead Discussants: Phil Dixon, Ph.D., Michael Newman, Ph.D. and Christopher Portier, Ph.D.
10. Routes of Exposure . Due to the high solubility (~700 ppm) of ChemX in water, dietary and sediment associated routes of exposure were not considered. Does the Panel agree that this is sufficient for ChemX? What are the Panel's thoughts on when these additional routes should be considered, in terms of specific physico-chemical parameters and values?
Lead Discussants: Kirk Hatfield, Ph.D. and George Cobb, Ph.D.
- 2:30 PM ADJOURNMENT
Please be advised that agenda times are approximate. For further information, please contact the Designated Federal Official for this meeting, Mr. Paul Lewis, via telephone: (703) 305-5369; fax: (703) 605-0656; or email:lewis.paul@epa.gov.