UNITED S TATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C., 20460
OFFICE OF CHEMICAL SAF ET Y AND POL L UT I ON PREVENTION

PC Code: 002201
DP Barcode : 427826
Date : September 8, 2015

MEMORANDUM

Subject:

From:

Through:

To: Registrat i on Review: Prob l em Formulation for the Environmental Fate, Ecological Risk, Endangered Species, and Drinking Water Assessm nts f r S badilla Alkaloids 

## _/ q/,;/')..01) Freeborn Jewett, M.S., Biologis v-:::J He Zhong, Ph.D

., Biologist 

# 9 

# I 'if 

# I,. o/ 

## ..r
Environmental Risk Branch I Environmental Fate and Effects Division (7507P)

### o~ 

# q/s/1)
Greg Orrick, Risk Assessment Process Leader

# ~**~** \ 

## g \ \ .j Sujatha Sankula ; Ph.D., Branch Chief

## h~A~-1'--.......J**~** Env i ronmental Ri sk Branch I ' -=- ,,. '
Env ironmental Fate and Effects Division (7507P)

Roy Johnson, Chemical Review Manager Jill B loom

, Team Leader Linda Arrington, Branch Chief Risk Management and Implementation Branch V Pesticide Re -E valuation Division (7508P)

12

1. Executive Summary:
The Environmental Fate and Effects Division (EFED) has completed the problem formulation for the environmental fate, ecological risk, endangered species, and drinking water exposure assessments to be conducted as part of the Registration Review of the insecticide s abadilla alkaloids ( CAS Number 8051

- 02

- 3 ) . Sabadilla alkaloids refers to a mixture of several alkaloids, veratridine, cevadine, sabadilline, sabadinine, and sabadine
, which are derived from the crushed seeds of the sabadilla lily ( Schoenocaulon officinale )

. The sabadilla alkaloid mixture is composed primaril y of cevadine and veratridine, with smaller amounts of other alkaloids such as sabadine
, sabadinine, and sabadilline (Tomlin

, 2003 ). One product containing s abadilla alkaloids is currently registered for use under the na me Veratran D (0.2% ai) (EPA reg. #1 021

- 2600 ), for the control of thrips in avocados, mangos and citrus. Veratran D is allowed for use in certified organic operations under the USDA National Organic Program . It is formulated as a wettable powder that is mixed with water and applied by aerial or ground application. The label for Veratran D requires clarification, as the current language does not specify a maximum annual application rate, a maximum number of applicati ons /year, or a minimum retreatment interval

.
Functioning as the first stage of the risk assessment process for Registration Review, this problem formulation provides an overview of what is currently known about the environmental fate and ecological effec ts associated with sabadilla alkaloids . It also describes the preliminary ecological risk hypothesis and analysis plan for evaluating and characterizing drinking water exposure and risk to non

target species and the environment in support of the Registrati on Review of sabadilla alkaloids . This document also recommends studies to address uncertainties related to the environmental fate and ecological effects of sabadilla alkaloids

.

There are no recent actions on sabadilla alkaloids. Sabadilla alkaloids was last assessed in 2004 in the Registration Eligibility Decision (RED; EPA, 2004a). This assessment was conducted with limited data and relied primarily on predicted toxicity and fate values to characterize risk. These predicted toxicity values should not b e used in future assessments

.

Recommended Studies : The list of recommended studies reflects a tiered approach

. The first tier of recommended studies is needed to confirm the assumption from the RED that no risk exceedances exist (i.e. RQ < LOC) for
terrestr ial and aquatic taxa. If risk concerns are identified , a second tier of data is recommended

. In the absence of fate data, EFED will assume stability of the sabadilla alkaloid mixture

.

Table 1 : A Summary of Recommended Data for Sabadilla Alkaloids

Taxa Test Substance

(F or T ier I and Tier II) Tier I Tier II

Eco Data

Aquatic Invertebrates TGAI 1  850.1010 Freshwater Invertebrate Acute Toxicity  850.1035 Estuarine/Marine Invertebrate Acute Toxicity (Mysid shrimp)

1 Sabadilla Alkaloids TGAI refers to a mixture of sabadilla alkaloids that would be representative of the active ingredient found in a typical commercially available formulation of Veratran D. S abadilla alkaloids is a powder derived from dried seeds of plants in the lily family, and it has been reported that there is significant variation (>33

Taxa Test Substance

(F or T ier I and Tier II) Tier I Tier II

 850.1300 Freshwater Invertebrate Life Cycle  850.1025 Estuarine/Marine Invertebrate Acute Toxicity (Eastern Oyster)

 850.1350 Estuarine/Marine Invertebrate Life Cycle Benthic Invertebrates TGAI

--  850.1735 Whole sediment 2 : Invertebrates Subchronic: Freshwater amphipod, Hyalella azteca , and midge, Chironomus dilutus

 850.1740 Whole sediment 2 : Invertebrates Subchronic: Estuarine/marine amphipod Leptocheirus plumulosus

 Non

- Guideline Chronic Sediment Toxicity Test (if risks are identified in subchronic tests) Fish TGAI  850.1075 Freshwater Fish Acute Toxicity ( cold water species)

 850.1400 Freshwater Fish Early

- Life Stage (cold water species)  850.1075 Freshwater Fish Acute Toxicity ( warm water species )

 850.1075 Estuarine/Marine Fish Acute Toxicity

 850.1400 Freshwater Fish Early

- Life Stage (warm water species)

 850.1400 Estuarine/Marine Fish Early

Life Stage Aquatic Plants TGAI  850.4400 Aquatic Vascular Plant Toxicity Test using Lemna spp.

 850.4500 Algal Toxicity Pseudokirchneriella subcapitata  850.4500 Marine diatom

- Skeletonema
costatum

 850.4500 Freshwater diatom

- Navicula pelliculosa

 850.4550 Blue Green Algae/ Cyanobacterium

- Anabaena flos

- aquae Birds TGAI  850.2100 Avian Acute Oral Toxicity (Bobwhite Quail)

 850.2300 Avian Reproduction (Bobwhite Quail)  850.2100 Avian Acute Oral Toxicity (Mallard Duck)

 850.2100 Avian Acute Oral Toxicity (Passerine species)

 850.2200 Avian Dietary Toxicity (Bobwhite Quail and Mallard Duck )

 850.2300 Avian Reproduction (Mallard Duck)

 850.2200 Avian Dietary Toxicity

fold) in the concentrations of veratridine and cevadine (Hare and Morse, 1997) in the finished product . As a result, all studies conducted with sabadilla alkaloid TGAI should be carried out w ith the same relative proportions of veratridine, cevadine, sabadinine, and sabadine in the mixture. Analytical confirmation of the concentration of each component (veratridine, cevadine, sabadinine, and sabadine) must be provided in the study report for each
test . Furthermore, the registrant needs to submit confirmatory analysis that demonstrates that the sabadilla alkaloids TGAI used for testing is representative of the composition of sabadilla alkaloids contained within a Veratran D, the typical end us e product (TEP)

. 2 Need ed if K OC values are analytically confirmed to be consistent with those predicted by EPISuite.4

Taxa Test Substance

(F or T ier I and Tier II) Tier I Tier II

Terrestrial Invertebrates TGAI  Non

- Guideline Tier I Honeybee Adult Acute Oral Toxicity

 Non Guideline Tier I

Honeybee Adult Chronic Oral Toxicity

 Non Guideline Tier I

Honeybee Larval Acute and Oral Exposure  Non

- Guideline Nectar and Pollen Residue Study for Insect Pollinators

 Non

- Guideline Semi

- Field Testing for Honeybees

 850.3040 Field Testing for Pollinators

Terrestrial Plants TEP 3  850.4100 Seedling Emergence and Seedling Growth  850.4150 Terrestrial Plants: Vegetative Vigor

Fate Data

Test Substance Tier I Data Requirement Tier II Data Requirement

Veratridine 4  835.2120

- Hydrolysis

 835.2240

- Aqueous Photolysis

 835.2410

- Soil Photolysis

 835.4100

- Aerobic Soil Metabolism

 835.4300

- Aerobic Aquatic Metabolism

 835.4400

- Anaerobic Aquatic Metabolism

 835.1230/835.1240 Leaching Adsorption/ Desorption

 850.1730

- Accumulation in Fish

 850.6100

- ECM/ILV (soil and water) --

Cevadine 4

--  835.4300

- Aerobic Aquatic Metabolism

 835.4100

- Aerobic Soil Metabolism

 835.2120

- Hydrolysis
TEP 3  835.6100

- Terrestrial Field Dissipation --

3 Veratran D

4 Two main insecticidal components of sabadilla alkaloid mixture5

1. Introduction
The purpose of this problem formulation is to provide an under standing of what is known about the environmental fate and ecological effects of sabadilla alkaloids

. This document will provide a plan for analyzing data relevant to sabadilla alkaloids and for conducting ecological risk, endangered species, and drinking water exposure assessments for i ts registered uses. T his problem formulation is intended to identify data gaps, uncertainties, and potential assumptions used to address those uncertainties relative to characterizing the ecological risk associated with the registered uses of sabadilla alk aloids

. The term “sabadilla alkaloids” refers to a class of insecticidal compounds that consists of a mixture of chemicals rather than a single chemical moiety. Sabadilla alkaloids (PC Code: 002201) is derived from the crushed seeds of the sabadilla lily ( Schoenocaulon officinale )

. The Registration Eligibility Decision ( USEPA , 2004 a ) evaluat ed sabadilla alkaloids as a potential low

- risk pesticide due to a lack of toxicity, and a risk assessment was performed on the alkaloids cevadine, veratridine, sabadine
, and sabadilline. The insecticidal action of this chemical class is primarily the result of two of the alkaloids, veratridine (CAS: 71

- 62

- 5) and cevadine (CAS: 62

- 59

- 9) (Allen et al., 1945; Hare and Morse, 1997; Ikawa et al., 1945). Sabadilla alkaloids is currently registered for use under the name of Veratran D (0.2% ai) (EPA reg. #1021

- 2600) for the control of thrips in avocados, mangos and citrus. Veratran D allowed for use in certified organic operations under the USDA National Organic Program. It is formulated as a wettable powder that is mixed with water and applied by aerial or ground application.
Limited data are available to characterize risk to terrestrial and aquatic taxa. Open literature studies provide qualitative endpoints on the toxicity o f sabadilla alkaloids to freshwater fish, mammals, and terrestrial invertebrates. Uncertainty related to the available open

- literature data, and a lack of registrant

- submitted data related to the environmental fate and toxicity effects of sabadilla alkalo ids, means that it is difficult to characterize the risk picture of sabadilla alkaloids to non

- target species. In the absence of data, future risk assessments may be conducted based on conservative assumptions. In addition, there are label deficiencies tha t require clarification. The current label for the only registered product, Veratran

- D, does not specify a maximum annual application rate, a maximum number of annual applications , or a minimum retreatment interval

. Use Characterization

a. Mode of Action

Th e mode of action of sabadilla alkaloids is a sodium channel effect (delayed channel closure and an increase in the probability of channel opening) resulting in nerve excitation (repetitive firing), prolonged impulse duration and depolarization of nerve mem brane potential , resulting in death

. These alkaloids bind at the neurotoxin receptor 2 associated with voltage gates sodium channels to cause Na+ channels to stay open during a sustained membrane depolarization (Catterall

, 1975). The consequential Na+ infl ux, either by itself or by causing a maintained depolarization, leads to many secondary effects such as increasing pump activity, Ca2+ influx, and in turn
, exocytosis.

b. Overview of Pesticide Use and Usage
The most recent available usage summary of sabadil la alkaloids is available for California in 2012 (Pesticide Action Network, 2015), and is presented in Table 2

. In 2012, 66.2 lbs ai were applied over 3,928 acres.6

The Biological and Economic Analysis Division (BEAD) provided a Screen ing Level Usage Analysis (SLUA) (USEPA, 2014a) to provide estimates of the actual usage of sabadilla alkaloids on agricultural crops. The screening level usage profile (SLUA) produced by BEAD and located in the docket (USEPA, 2014a) and summarized in Table 3 , lists the use patterns for the current uses of acequinocyl. Primary uses in terms of average weight of applied product of sabadilla alkaloids ar e avocados, grapefruit, lemons, oran g es and tangerines . These data represent annual data from 2004

- 2012

.

Sabadilla alkaloids is currently registered under a single formulated product , Veratran D, which is composed of 0.2% sabadilla alkaloids and 99.8% other ingredients and is registered for use on avocados, mangoes and citrus . The single maximum application rate for Veratran

- D is 15 lbs formulated product per acre (0.03 lbs ai/A) for aerial application and 20 lbs formulated product per acre (0.04 lbs ai/A) for ground application to avocados, citrus and mangos. The current label directs applicators to, “reappl y as necessary, usually at a 10

- 14 day interval.” Therefore, multiple applications will be assessed.

Table 2 : Estimates of the Actual Usage of Sabadilla Alkaloids on Agricultural Crops in California in 2012 (Pesticide Action Network, 2015).

Crop Gross Poun ds ai Application rate (lb ai /A) Acres Treated Tangerines 53 0.02 3,305
Avocado 7 0.03 237 Oranges 2.93 0.02 157 Outdoor Container Nursery 1.33 0.02 39.3 Grapefruit 0.82 0.02 80.0 Tangelos 0.60 0.02 30.0
Citrus 0.48 0.02 80.0
Statewide Total 66.2 0.02 3,928

Table 3: Estimates of the Actual Usage of Acequinocyl on Agricultural Crops (USEPA, 2014a).

Crop Average Percent Crop Treated

Lbs. A.I. Average Maximum

Avocados <500 <2.5 5 Grapefruit <500 <1 <2.5
Lemons <500 <1 <2.5 Oranges <500 <1 < 2.5 Tangerines <500 <2.5 <2.5

2. Conclusions from Previous Actions

a. Ecological Risk Assessment

Sabadilla alkaloids was last assessed in 2004 for the Registration Eligibility Decision (RED; EPA, 2004a). The previous assessment focused on the alkaloids veratridine, cevadine, sabadine, and sabadinine. Sabadilline was mentioned in the RED as a component of the alkaloid mixture, but no confirmation of7

the existence of this alkaloid could be located in the lit erature, so it will not be discussed as part of this document

.
Due to the lack of registrant

- submitted data on the fate and effects characteristics, the RED relied on EPISuite, 5 a collection of physical/chemical property and environmental fate/effects estimation programs. ECOSAR, part of the suite of programs, was developed by the EPA’s Office of Pollution Prevention Toxics and was utilized to estimate fate characteristics and aq uatic toxicity of sabadilla alkaloids. ECOSAR employs quantitative structure activity relationships (QSARs) to predict aquatic toxicity of veratridine, cevadine, sabadine, and sabadinine based on their structural similarity to chemicals for which toxicity has previously been measured. Reliability of the predictive capacity of ECOSAR modeling is determined based on how closely the modeling program can estimate the toxicity of the parent compound.

A single open

- literature study measured the acute toxicity o f the formulated product, Red Devil Dust (0.8% ai ; currently non

- registered formulation ) on bluegill sunfish (MRID 25601008) . Th e toxicity endpoint for bluegill sunfish calculated in this study indicated that Red Devil Dust is four orders of magnitude more toxic than the ECOSAR

- predicted toxicity values for veratridine, cevadine, sabadine, and sabadinine. This indicates that there is too much uncertainty to use ECOSAR

- predicted toxicity values to qualitatively assess risk to aquatic taxa at this time. T he R ED (USEPA, 2004 a ) used ECOSAR to provide a rough characterization of risk to aquatic taxa and this approach should not be used in future
assessments

.

The RED (USEPA, 2004 a ) characterized risk to terrestrial organisms based on limited studies conducted wi th rats and honeybees. The RED concluded that there may be risks from exposure of total sabadilla alkaloids to listed and non

- listed mammals. This conclusion was based on an LD50 of 44 mg ai/kg

- bw, estimated using a probit analysis of data from two acute r at toxicity studies. Since the RED, another study with rats has been submitted that reported an endpoint of >10mg ai/kg bw. The RED also concluded that sabadilla alkaloids are practically non

- toxic on a contact basis to honeybees based on an LD50= 12.3 μg formulated product/Bee. The formulation was Veratrine (CAS: 8051

- 02

- 3; Purity not reported), which is no longer registered.

b. Drinking Water Exposure Assessments

The most recent drinking water assessment ( DWA ) was conducted in support of the RED (USEPA, 2004a). Calculation of the EDWCs was carried out with aerobic soil half

- lives that were estimated using the Biodegradation Probability Program (BIOWIN) contained in EPIWIN v.3.11 (2000). This program estimates the probability of the rapid aerobic biodegradation of an organic chemical in a mixed population of microorganisms.
Tier I Estimated Drinking Water Concentrations (EDWCs) were calculated by incorporating predicted degradation values in FIRST v. 1.0 (surface water) and SCIG ROW v. 2.3 (ground water). The peak surface water concentrations ranged between 1.6 ppb and 1.8 ppb. The average annual surface water concentrations ranged between 0.05 ppb and 0.07 ppb, depending on the alkaloid assessed. Ground water concentrations were estimated to be 0.0007 ppb. Monitoring data were not available for use in this assessment.

5 http://www.epa.gov/opptintr/exposure/pubs/episuite.htm8

Due to the uncertainty related to the use of estimated fate data in the BIOWIN without any empirically

derived data to compare for accuracy, the EDWC values predicte d in that assessment should be interpreted with caution and EFED recommends against their use in subsequent risk characterization.

c. Clean Water Act Programs

Sabadilla alkaloids is not identified as a cause of impairment for any bodies listed as impaired un der section 303(d) of the Clean Water Act (as of 11/2014). 6 A Total Maximum Daily Load (TMDL) has not been developed. 7 The Agency invites submission of water quality data for this pesticide. To the extent possible, data should conform to the quality stan dards in Appendix A of the OPP Standard Operating Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in OPP’s Registration Review Risk Assessment and Management Process 8 , in order to ensure they can be used quantitatively or qualitati vely in pesticide risk assessments.

3. Environmental Fate and Transport

The estimated physical and chemical properties of sabadilla alkaloids : veratridine, cevadine, sabadinine, and sabadine are summarized in Table 4

. T he se steroidal alkaloids are characterized by a close structural relationship with sterols. They contain a perhydro

- 1, 2

- cyclopentanophenanthrene nucleus and are often associated with glycosidic complexes in plant tissues, where they hydrolyze to free the alkaloid. Veratridine an d cevadine are characterized by the presence of an oxygen bridge between carbons 4 and 9 and a shared nitrogen on the fifth and six rings and terminal esters on ring one. As shown in Table 4 , t he compounds are of low water solubility and have high pKa (> 9 for veratridine; McKinney et al. 1986).
No submitted data are available on the physical and chemical properties or the environmental fate of sabadilla alkaloids. From the open literature data, s abadilla alkaloids are reported to be very unstable in the presence of light and decompose rapidly by photodegradation (Metcalf 1995; Tomlin 2003); however, no rates were provided. This qualitative information suggests that photolysis on the surface of plants, water, and soil is a likely degradation process. A fi eld trial with Veratran

- D formulation showed that l evels of cevadine and veratridine on leaves declined to 60% from the initial deposit within 20 h of application and to undetectable levels w ithin 7 d ( Hare and Morse, 1997 )

. Pelletier and Jacobs (1953)
rep orted that a gentle saponification of cevadine yields a new alkanolamine, veracevine, which contains one double bond and eight hydroxyl groups.

The volatilization of s abadilla alkaloids from soil and water surfaces is not considered an important environm ental pathway based on the estimated vapor pressure s and Henry's Law constants.

The dissociation constants (pKa) of sabadilla alkaloids are above 9 suggesting these compounds tend to exist in the neutral, protonated form in water and moist soils, and not as the free base. Based upon the estimated Koc values, these alkaloids may have very low mobility in soils. Consequently, leaching to groundwater is not expected to be an important environmental fate process. However, log Kow estimates are low, indicat ing that these alkaloids may not sorb substantially to suspended solids and sediment in aquatic systems. The environmental fate of sabadilla alkaloids is uncertain in the absence of guideline

- compliant environmental fate studies . Physical and chem i c al info rmation is not available for sabadi l line (USEPA 2004a RED). In the absence of fate data, future assessments will assume stability.

6 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885

7 http://iaspub. epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollut ant_group_name=PESTICIDES

8 http://www.epa.gov/oppfead1/cb/ppdc/2006/november06/ session1

- sop.pdf9

Table 4 . Physical and Chemical Properties of Sabadilla Alkaloids
Parameter Value Reference Chemical Veratridine USEPA, 2004a Chemical Name (3beta,4alpha,16beta)

- 4,12,14,16,17,20

- Hexahydroxy

- 4,9

- epoxycevan

- 3

- yl 3,4

- dimethoxybenzoate

EPI Suite v 4.1 CAS Number 71

- 62

- 5
Structure

SMILES C[C@H]1CC[C@H]2[C@@]([C@]3([C@H](C[C@]4([C@@H ]5CC[C@H]6[C@]7([C@]5(C[C@]4([C@@H]3CN2C1)O)O[ C@@]6([C@H](CC7)OC(=O)C8=CC(=C(C=C8)OC)OC)O)C)O) O)O)(C)O Chem Spider 9

Molecular formula C 36 H 51 NO 11

EPI Suite v 4.1 Molecular weight 673.8 Vapor Pressure (25 o C) 1.51 ×10

- 24 mm Hg Henry’s Law constant 4.65 ×10

- 25 atm m 3 mol

- 1 Log K OW 0.678
K OC 3.2x 10 5 Water Solubility mg/L) 141 Dissociation constant (pKa) 9.54 RED

Chemical Cevadine USEPA, 2004a Chemical Name (3beta,4alpha,9beta,16beta)

- 4,12,14,16,17,20

- Hexahydroxy

- 4,9

- epoxycevan

- 3

- yl (2Z)

- 2

- methyl

- 2

- butenoate

EPI Suite v 4.1 CAS Number 62

- 59

- 9
Structure

9 CSID:391289, http://www.chemspider.com/Chemical

- Structure.391289.html (accessed 15:06, Jun 4, 2015)10

Table 4 . Physical and Chemical Properties of Sabadilla Alkaloids
Parameter Value Reference
SMILES C/C=C(/C) \ C(=O)O[C@H]1CC[C@]2([C@H]3[C@@]1(O[C @@]24C[C@]5([C@@H]6CN7C[C@H](CC[C@H]7[C@@]([ C@]6([C@H](C[C@]5([C@@H]4CC3)O)O)O)(C)O)C)O)O)C Chem Spider

Molecular formula C 32 H 49 NO 9

EPI Suite v 4.1 Molecular weight 591.7 Vapor Pressure (25 o C) 5.68 ×10

- 20 mm Hg Henry’s Law constant 8.69 ×10

- 22 atm m 3 mol

- 1 Log K OW 0.89
K OC 2.0 x 10 5 Water Solubility (mg/L) 320.4

Dissociation constant (pKa) 9.2 RED

Chemical Sabadinine USEPA, 2004a Chemical Name (3alpha,4alpha,16beta)

- 4,9

- Epoxycevane

3,4,12,14,16,17,20

- heptol

EPI Suite v 4.1 CAS Number 124

- 98

- 1
Structure

SMILES C[C@H]1CC[C@H]2[C@@]([C@]3([C@H](C[C@]4([C@@H ]5CC[C@H]6[C@]7([C@]5(C[C@]4([C@@H]3CN2C1)O)O[ C@@]6([C@@H](CC7)O)O)C)O)O)O)(C)O Chem Spider

Molecular formula 509.65

EPI Suite v 4.1 Molecular weight C 27 H 43 NO 8 Vapor Pressure (25 o C) 3.0 ×10

- 19 mm Hg Henry’s Law constant 1.0 ×10

- 20 atm m 3 mol

- 1 Log K OW - 1.20 K OC 1.3 x10 5 Water Solubility mg/L) 6.727 x 10 4 Dissociation constant (pKa) 9.2 RED

Chemical Sabadine USEPA, 2004a Chemical Name (3beta,4alpha,16beta)

- 4,12,14,16,17,20

- Hexahydroxycevan

- 3

- yl acetate EPI Suite v 4.1 CAS Number 124

- 80

- 111

Table 4 . Physical and Chemical Properties of Sabadilla Alkaloids
Parameter Value Reference
Structure

SMILES C[C@H]1CC[C@H]2[C@@]([C@]3([C@H](C[C@]4([C@@H ]5CC[C@@H]6[C@@H]([C@H](CC[C@@]6([C@H]5C[C@] 4([C@@H]3CN2C1)O)C)OC(=O)C)O)O)O)O)(C)O Chem Spider

Molecular formula 537.7

EPI Suite v 4.1 Molecular weight C 29 H 47 NO 8 Vapor Pressure (25 o C) 1.26 ×10

- 19 mm Hg Henry’s Law constant 1.37 ×10

- 18 atm m 3 mol

- 1 Log K OW 0.32
K OC 1.6x10 5 Water Solubility mg/L) 2232 Dissociation constant (pKa) 9.2 RED

4. Receptors
Consistent with the process described in the Overview Document (USEPA , 2004b), a risk assessment for sabadilla alkaloids will rely on a surrogate species approach. Toxicological data generated from surrogate test species, which are intended to be representative of broad taxonomic groups, will be used to extrapolate the potential effe cts on a variety of species (receptors) included under these taxonomic groupings. Table 5 provides a summary of the available endpoints that could be used to characterize the potential effects of sabadilla alkaloid exposure.

No registrant

- submitted data are available for toxicity of sabadilla alkaloids to aquatic species . Open literature suggested a formulated product containing sabadilla alkaloids, Red Devil Dust ® (0.8% ai), is very highly toxic to fish , h owever Red Devil Dust is no longer registered for use. It is unclear how this toxicity is related to the toxicity of the individual components of the mixture, as the mixture was not characterized. The RED estimated an LD50 44 mg ai/kg

- bw for acute exposure to rats based the probit analysis of two studies provided b y the California Environmental Protection Agency in 2001. The validity of these data could not be confirmed, as the original studies and reviews of these studies could not be located. A registrant

- submitted study conducted with rats using Veratr an

- D did not record any toxicity effects up to the maximum dosage of 10 mg formulation /kg

- bw. The authors did not correct for % a.i, so the LD50 for the sabadilla alkaloids contained in Veratran

- D, assuming a 0.2% a.i. as written on the current label, would be >10 mg ai/kg

- bw. As a result of this non

- definitive endpoint, the acute endpoint for rats is presumed to be 44 mg ai/kg

- bw. Sabadilla alkaloids is practically nontoxic to adult honeybees on an acute contact basis.12 Table 5 : Available Toxicity Endp oints for Sabadilla Alkaloids
Taxa Study Type % ai Species Toxicity Value & Category MRID &

Status Endpoints

Affected

Freshwater fish Acute

850.1075 TEP

0.8 Bluegill Sunfish

Lepomis macrochirus LC50=89 μg ai 1 /L

NOAEC <49 μg ai/L

Very Highly Toxic 25601008 Supplemental

quantitative

Characterized toxicity of TEP (Red Devil Dust formulation that is no longer registered) Mortality

Mammals Acute oral

870.1100 TEP

(0.2%) 2 Rat

Rattus norvegicus LD50 >5000 mg

Veratran

- D/kg

- bw or
LD50 > 10 mg ai/kg

- bw 46372101 Supplemental

Qualitative

Sabadilla alkaloids present in mixture could not be characterized None

Terrestrial invertebrates Adult Acute

Contact 850.3020 NR Honeybee Apis mellifera 48

- hr LD50= 12.33 μg

formulation /bee

Practically Nontoxic 00001999 Supplemental

Qualitative,

Characterized toxicity of TEP ( Veratrine, a formulation that is no longer registered

. Purity was not reported ) None

2 Assumed based on current Veratran

- D label. NR=Not reported

The RED (USEPA, 2004a) characterized toxicity values using the Ecological Structure Activity Relationship (ECOSAR) program within the EPI Suite of environmental fate/effects programs. EPI Suite is a screening

level tool and should not be used if acceptable measured values are available

. Because of the lack of empirically

- derived data assessing the toxicity of the various alkaloids to aquatic taxa, there is no basis for assessing the reliability of the predicted values for the other aquatic taxa until more d ata are submitted

.13 a. Degradate toxicity
The degradate veracevine is formed from the hydrolysis of veratridine (Pelletier and Jacobs, 1953). Hare and Morse (1997) compared the toxicity of the insecticidal components of Veratran

- D, veratridine and cevadine, w ith that of the degradate, veracevine. The authors reported that veracevine was 500

- 3,000 times less toxic than cevadine and veratridine to the adult female citrus thrip, Scirtothrips citri

. Figure 1 compares the toxicity of veratridine, cevadine and verac evine to the target pest species, thrips. EFED will conduct a formal review of this study to ensure that the methods and information reported are suitable for use in risk assessment.

Figure 1 : Comparison of the Toxicity of Veratridine, Cervadine and degradate Verac e vine to Citrus Thrips (Hare and Morse, 1997)

b. Ecological Incidents
The Ecological Incident Information System or EIIS maintained by the Environmental Fate and Effects Division, and the Avian Incident Monitoring System (AIMS) maintained by the American Bird Conservancy, were searched on June 1 , 201 5 and no ecological incid ents were recorded resulting from the use of sabadilla alkaloids

. In addition to the incidents recorded in EIIS and AIMS, additional incidents are reported to the Agency in aggregated form. Pesticide registrants report certain types of incidents to the Age ncy as aggregate counts of incidents occurring per product per quarter. Ecological incidents reported in aggregate reports include those categorized as ‘minor fish and wildlife’ (W

- B), ‘minor plant’ (P

- B), and ‘other non

- target’ (ONT) incidents. ‘Other no n

- target’ incidents include reports of adverse effects to insects and other terrestrial invertebrates. There have been no reported incident summaries for sabadilla alkaloids as of June 1 , 201 5

.14

5. Exposure Pathways of Concern
EFED's environmental exposure models estimate the potential exposure of plants and animals to pesticide residues in aquatic and terrestrial environments based on registered labels including maximum sabadilla alkaloid application rates and intervals. A quatic models can also be utilized to estimate pesticide residues in drinking water for use in the dietary exposure models. A more detailed description of aquatic and terrestrial models can be found at the following website: http://www.epa.gov/pesticides/science/models_db.htm

.
The Screening Imbibition Program (SIP v.1.0) is used during the problem formulation phase of Registration Review to provide an upper

- bound estimate of exposure of b irds and mammals to pesticides through drinking water alone. SIP does not aggregate the drinking water exposure route with other exposure routes ( i.e., dietary, inhalation, dermal).

The Screening Tool for Inhalation Risk (STIR v.1.0) is used during the p roblem formulation phase of Registration Review to assess the potential for exposure to birds and mammals through inhalation. The exposure pathways that are assessed by this tool include both droplet inhalation and vapor phase inhalation. STIR is intended to determine if exposure is likely and not whether or not the potential for risk exists. If STIR predicts that exposure is likely, additional inhalation data may be necessary to adequately assess risk due to the inhalation exposure pathway.

Due to a lack of toxicological endpoints and information on the chemical properties of sabadilla alkaloids, SIP and STIR could not be used to predict the potential for exposure to non

- target species through inhalation or drinking water.

6. Analysis Plan

a. Stressors of Concern
The stressors of ecological concern for terrestrial/aquatic plants and animals are the primary components of the commercially available formulation of sabadilla alkaloids : veratridine, cevadine, sabadine, and sabadinine. Sufficient data are not ava ilable to exclude any alkaloids in the sabadilla alkaloid mixture as potential stressors of concern.

i. Ecological Risk Assessment

Open literature indicates that the primary insecticidal actors of the sabadilla alkaloid mixture are veratridine and cevadine (Pelletier and Caventou, 1819; Allen et al. 1945; Ikawa at al., 1945; Walton, 1947; Bergmann et al., 1958; Hare and Morse, 1997; Humeres and Morse, 2006). Hare and Morse (1997) show that the toxicity of each varies amo ng species.

In the absence of the requested studies, EFED may not be able to assess risk to certain taxa or may need to rely on data with tremendous uncertainty. It may be possible to use toxicity endpoints from chemicals with structural similarities or modes of action, but this course of action could overestimate risk to certain taxa. For example, sabadilla alkaloid’s effect on sodium nerve channels is a mode of action shared with the pyrethrins and pyrethroids

.
Upon receiving the Tier I aquatic and te rrestrial toxicity studies, toxicity endpoints for sabadilla alkaloids will be approximated by deriving a toxicological endpoint for each of the four constituents on a15

proportional basis, assuming that the toxicity of the mixture is conservatively explaine d by the amount of each constituent separately. In this manner, the observed toxicity of the mixture could be adjusted based on the amount of each of the fo ur compounds. These compound

- specific estimates of toxicity can be compared with the relative expect ed amounts of each constituent in environmental media and could account for differences in formulation composition as well as exposure refinements resulting from submission of fate data

. This approach also accounts for any possible synergistic effects that would not be reflected if alkaloid components were tested individually. In the absence of fate data
, stability of the alkaloids will be assumed for modeling purposes.

ii. Drinking Water Assessment

The last drinking water assessment ( DWA ) was conducted in 20 04 as part of the RED (D P 304789 ). A new DWA will be conducted as part of the registration review
, which will include the alkaloids veratridine and cevadine as well as any other alkaloids or degradates of concern as identified using gui deline

compliant environmental fate and toxicity data.

b. Measures of Exposure
EFED will use standard available exposure models to evaluate potential exposures to aquatic and terrestrial organisms as described at http://www.epa.gov/pesticides/science/models_db.htm

.

i. Available Monitoring Data
EFED will consider available monitoring data from federal and state agencies or other sources. The Agency we lcomes submission of monitoring data.

c. Measures of Effect
Ecotoxicity data presented in Table 5 of this problem formulation may be used to calculate risk quotients. Any additional information submitted by the registrant or found in the open literature pri or to conducting the risk assessment will also be considered. The open literature studies will be identified using EPA’s ECOTOXicology database ( ECOTOX 10 ) , which employs a literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants, and wildlife.

7. Endangered Species Assessment
Consistent with EPA’s responsibility under the Endangered Species Act (ESA), the Agency will evalua te risks to federally listed threatened and endangered (listed) species from registered uses of pesticides in accordance with the Joint Interim Approaches developed to implement the recommendations of the April 2013 National Academy of Sciences (NAS) repor t, Assessing Risks to Endangered and Threatened Species from Pesticides

. The NAS report outlines recommendations on specific scientific and technical issues related to the development of pesti cide risk assessments that EPA and the Services must conduct in connection with their obligations under the ESA and FIFRA. In November 2013, EPA, the U.S. Fish and Wildlife Service, National Marine Fisheries (the Services), and USDA released a white paper containing a summary of their joint Interim Approaches for assessing risks to listed species from pesticides. These Interim Approaches were developed jointly by the agencies in response to the NAS recommendations, and reflect a common approach to risk as sessment shared by the agencies as a way of addressing scientific differences between the EPA and the Services. Details of the joint Interim Approaches are contained in the November 1, 2013 white paper
, Interim Approaches for National

- Level Pesticide

10 http://cfpub.epa.gov/ecotox/16

Endangered Species Act Assessments Based on the Recommendations of the National Academy of Sciences April 2013 Report.
Given that the agencies are continuing to develop and work toward implementation of the Interim Approaches to assess the potential risks of pesticides to listed species and their designated critical habitat, this ecological problem formulation supporting the Preliminary Work Plan for sabadilla alkaloids does not describe the specific ESA analysis, including effects determinations for specific listed species or designated critical habitat, to be conducted during registration review. While the agencies continue to develop a common method for ESA analysis, the planned risk assessment for the registration review of sabadilla alkaloids will describe the level of ESA analysis completed for this particular registration review case. This assessment will allow EPA to focus its future evaluations on the types of species where the potential for effec ts exists, once the scientific methods being developed by the agencies have been fully vetted. Once the agencies have fully developed and implemented the scientific methods necessary to complete risk assessments for listed species and their designated crit ical habitats, these methods will be applied to subsequent analyses of sabadilla alkaloids as part of completing this registration review.

8. Endocrine Disruptors Screening Program

Sabadilla alkaloids was not included in either the first or second group of c hemicals issued an order to conduct Tier I EDSP testing, for more information on the EDSP program, visit http://www.epa.gov/endo/

.
9. Preliminary Identification of Data Gaps

Table 6 presents a list of the fate and effects data gaps, as well as a list of studies that EFED i s recommending for submission

. Aquatic and terrestrial toxicity studies will characteriz e the toxicity of the active ingredient found in Veratran

- D

. S abadilla alkaloids is derived from dried see ds of plants in the lily family and it has been reported that there is significant variation (>3 fold) in the concentrations of veratridine and cevadine depending on the year that the product was produced (Hare and Morse, 1997). As a result, toxicity studies on aquatic and terrestrial taxa must submit a report of the % composition of veratrine, cevadine, sabadine, and sabadinine contained in the test mixture , and a consistent test mixture composition must be maintained across all tests. Terrestrial plant seed ling emergence and growth studies should be conducted with Veratran

- D TEP.
The recommendations include representative species from each taxonomic group that includes fish, aquatic invertebrates, terrestrial plants, aquatic plants, and birds. The requested data reflect a tiered approach to characterizing risk of sabadilla alkaloids to terrestrial and aquatic taxa. The first tier of requested studies will be used to confirm that no risk exceedances exist (i.e. RQ>LOC) to representative terrestrial and aquati c taxa. If risk concerns for a particular taxa are identified, then a second tier of data for that taxa is recommended

.

In the absence of fate data, future assessments will assume stability for sabadilla alkaloids. The t ier I set of fate studies will cha racterize the fate properties of the largest molecule, veratridine, which is suspected to be the final product of the biosynthesis pathway in the sabadilla lily seeds

. If risk concerns are identified for any taxa, Tier II fate data will characterize the en vironmental fate characteristics of t he second primary insecticidal component of sabadilla alkaloids, cevadine.17 Table 6

. Environmental Fate and Effects Data Gaps and Recommended Studies for Sabadilla Alkaloids Data Requirement Data Gap? Tier I Tier II Test Substance Comments

850.1010 Freshwater Invertebrate Acute Toxicity Yes Yes No TGAI 11

--

850.1035 Estuarine/Marine Invertebrate Yes No Yes TGAI

--

850.1025 Oyster Toxicity Yes No Yes TGAI

--

850.1300 Freshwater Invertebrate Life Cycle (Chronic) Yes Yes No TGAI

--

850.1350 Estuarine/Marine Invertebrate Life Cycle Yes No Yes TGAI

--

850.1735 Subchronic Freshwater Sediment Toxicity Test Yes No Yes TGAI Sediment invertebrate toxicity data are required under 40 CFR Part 158 if any of the following exist: A. The soil partition coefficient (Kd) is ≥ 50 B. The log Kow is ≥ 3. C. The Koc is ≥ 1,000.

The K oc for Veratridine is 32,000, 20,000 for cevadine, 13000 for sabadinine, and 16000 for sabadine, indicating the potential for risk to benthic invertebrates. Because of the lack of half

- life values, it is uncertain whether a subchronic or chronic toxicity woul d better characterize risk to benthic organisms. As a result, a tiered testing strategy (as outlined in USEPA, 2014 b ) may be 850.1740 Subchronic Estuarine/marine Sediment Toxicity Test Yes No Yes TGAI

Non Guideline Chronic Sediment Toxicity Test Yes 12 No Yes TGAI

11 Sabadilla Alkaloids (TGAI) refers to a mixture of sabadilla alkaloids that would be representative of the active ingredient in a typical commercially available formulation of Veratran

- D. As sabadilla alkaloids is a seed powder derived from dried seeds of plants in the lily family, it has been reported that there i s significant variation (>3 fold) in the concentrations of veratridine and cevadine (Hare and Morse, 1997). As a result, studies conducted with sabadilla alkaloid TGAI should be carried out with a formulation of sabadilla alkaloids where the concentrations of veratridine, cevadine, sabadinine, and sabadine in the mixture are consistent for each study and an analytical confirmation is provided in the study report. Registrant needs to submit confirmatory analysis of the test substance to confirm that sabadill a alkaloids TGAI is representative of the composition of a typical product.18 Data Requirement Data Gap? Tier I Tier II Test Substance Comments

considered for implementing the necessary Data Call

- In requirements. In this approach, sediment toxicity testing would be conducted using the subchronic (10

- d) sediment toxicity test guidelines (OSCPP 850.1735 and 850.1740).
P ending a comparison of estimated environmental concentrations (EEC) in sediment and pore water with toxicity results from the 10

- d subchronic sediment toxicity

s tudies, one or more chronic sediment toxicity studies would be recommend ed. 850.1075 Freshwater Fish Acute Toxicity Yes Yes Yes TGAI Tier I

- Coldwater Species Tier II

- Warmwater Species

850.1075 Estuarine/Marine Fish Acute Toxicity Yes No Yes TGAI

--

850.1400 Fr eshwater Fish Early

- Life Stage Yes Yes Yes TGAI Tier I

- Coldwater Species Tier II

- Warmwater Species

850.1400 Estuarine/Marine Fish Early Life Stage Yes No Yes TGAI

--

850.4400 Aquatic Vascular Plant Toxicity Test using Lemna
spp. Yes Yes No TGAI

--

850.4500 Algal Toxicity Pseudokirchneriella subcapitata Yes Yes No TGAI

--

850.4500 Marine diatom Skeletonema
costatum Yes No Yes TGAI

--

850.4500 Freshwater diatom Navicula pelliculosa Yes No Yes TGAI

--

850.4550 Blue Green Algae/ Cyanobacterium Yes No Yes TGAI

--19 Data Requirement Data Gap? Tier I Tier II Test Substance Comments

Anabaena flos

- aquae 850.2100 Avian Acute Oral Toxicity (Upland game, passerine or waterfowl species) Yes Yes Yes TGAI Tier I

- Bobwhite Quail Tier II

- Mallard Duck and a passerine species

850.2200 Avian Dietary Toxicity Yes No Yes TGAI Upland game and waterfowl species 850.2300 Avian Reproduction Yes Yes Yes TGAI Tier I

- Bobwhite Quail Tier II

- Mallard Duck
850.3020 Tier I

- Honeybee Acute Adult Contact Toxicity No No No NA

--

Non

- Guideline (OECD 213)

- Tier I Honeybee Acute Adult Oral Toxicity Yes Yes No TGAI

--

Tier I

- Honeybee Adult Chronic Oral Toxicity Yes Yes No TGAI

--

Tier I

- Honeybee Larval Acute and Oral Exposure Yes Yes No TGAI

--

850.3030

- Tier II

- Honeybee Toxicity of Residues on Foliage No No No NA The acute contact 48

- hr LD50 was 12.33 μg ai/bee. This study is only t riggered if contact toxicity is less than 11 μg ai/bee. Non Guideline Tier II

- Nectar and Pollen Residue Study for Insect Pollinators Yes No Yes TEP

--

Non Guideline (OECD 75)

- Tier II Semi

- Field Testing for Honeybees Yes No Yes TEP

--

850.3040

- Field Testing for Pollinators Yes No Yes TEP

--

850.4100

- Seedling Emergence and Seedling Growth Yes Yes No TEP

850.4150

- Vegetative Vigor Yes No Yes TEP Fate Data 835.2120

- Hydrolysis Yes Yes Yes Tier I

– V eratridine Tier II

Cevadine
835.2240

- Aqueous Photolysis Yes Yes No Veratridine

835.2410

- Soil Photolysis Yes Yes No Veratridine20 Data Requirement Data Gap? Tier I Tier II Test Substance Comments

835.4100

- Aerobic Soil Metabolism Yes Yes Yes Tier I

– Veratridine Tier II

Cevadine --

835.4300

- Aerobic Aquatic Metabolism Yes Yes Yes Tier I

– Veratridine Tier II

Cevadine --

835.4400

- Anaerobic Aquatic Metabolism Yes Yes No Veratridine

--

835.1230/835.1240 Leaching Adsorption/ Desorption Yes Yes No Veratridine

--

835.6100

- Terrestrial Field Dissipation Yes Yes No TEP

--

850.1730

- Accumulation in Fish Yes Yes No Veratridine

--

850.6100

- ECM/ILV (soil and water) Yes Yes No Veratridine

--21

Justifications for N on - G uideline D ata R equirements: Study Title: Tier I

- Pollinator Chronic Oral Toxicity, Adult Rationale for Requiring the Data Terrestrial invertebrates are likely to be impacted if exposed to pesticides in various use settings. Pesticide residues may be transferred to pollen and/or nectar of treated plants and subsequently brought back to the hive. Therefore, potential chronic effects to adult honeybees and other pollinators from oral exposure to some pesticides could exist. Currently available toxicity studies do not address possible lethal and suble thal effects of chronic oral exposure on adult terrestrial invertebrates and will assist in determining whether the sensitivity of adult bees differs from that of earlier life stages. Because of the potential for pollen and nectar to be contaminated with p esticide residues, and subsequently brought back to the hive, it is important to determine the chronic oral toxicity of this compound to adult honeybees and other pollinators.

The Office of Pesticide Programs has made available a guidance regarding ecological testing for invertebrates with the honeybee. The guidance discusses Tier I laboratory

- based chronic oral toxicity studies of individual adult honeybees as a critical compon ent of the screening

- level risk assessment process for examining potential risks from specific routes of exposure. The guidance can be found at: http://www2.epa.g ov/pollinator

- protection/pollinator

- risk

- assessment

- guidance . Study design elements for the chronic 10

- day oral toxicity test with honeybees are similar to the OECD Test Guideline 213 acute oral toxicity test http://www.oecd

- ilibrary.org/environment/test

- no

- 213

- honeybees

- acute

- oral

- toxicity

test_9789264070165

- en

. Practical Utility of the Data How will the data be used? The Tier I chronic oral toxicity d ata on adult bees serve as a foundation for the screening

- level assessment of potential risk to non

- target organisms including federally listed threatened or endangered species and

non

- listed terrestrial invertebrate insects, includi ng pollinators, from chronic oral exposures to pesticides. The data will be used to reduce uncertainties associated with the risk assessment for terrestrial invertebrates and will improve EPA’s understanding of the potential direct and indirect lethal and sublethal effects on a broad range of terrestrial species, particularly insect pollinators and to determine whether adult toxicity differs substantially from other life stages evaluated in other Tier I tests. If chronic oral effects data for adults are n ot available, risks to terrestrial insects from chronic oral exposure will be assumed. How could the data impact the Agency’s future decision

- making? The data will inform the determination required under FIFRA or the ESA as to whether continued registration of a pesticide is likely to result in unreasonable adverse effects to non

- target species or is likely to adversely affect listed threatened or endan gered species and/or their designated critical habitat. Without these data, EPA may need to presume risk which will limit the flexibility of pesticide products to comply with FIFRA and the ESA, and could result in use restrictions.

Study Title: Tier I

- Pollinator Acute Oral Toxicity, Larvae Rationale for Requiring the Data Terrestrial invertebrates are likely to be impacted if exposed to pesticides in various use settings. Pesticide residues may be transferred to pollen and/or nectar of treated plants and subsequently brought back to the hive where larvae and pupae may be e xposed. Therefore, potential adverse effects to developing bees and other insect pollinators could result from exposure to pesticide residues. Available toxicity studies do not address possible effects on brood (larvae and pupae) survival/development. B ecause of the potential for pollen and nectar to be contaminated with pesticide residues, and subsequently brought back to the hive, it is important to determine the acute oral toxicity of this compound to bee brood.22

The Office of Pesticide Programs has made available a guidance regarding ecological testing for terrestrial invertebrates using the honeybee as a surrogate test species. The guidance discusses Tier I laboratory

based acute toxicity studies of individual honeybee larvae as a critical compone nt of the screening

- level risk assessment process for examining potential risks from specific routes of exposure. The guidance can be found at: http://www2.epa.g ov/pollinator

- protection/pollinator

- risk

- assessment

- guidance . Additional guidance on larval honeybee toxicity test design can be found in OECD Test Guideline 237 http://www.oecd

- ilibrary.org/environment/test

- no

- 237

- honey

- bee

- apis

- mellifera

- larval

- toxicity

- test

- single

exposure_9789264203723

- en

. Practical Utility of the Data How will the data be used? The Ti er I acute oral toxicity d ata on honeybee larvae serve as a foundation for the screening

- level assessment of potential risk to non

- target organisms such as federally listed threatened or endangered and

non

- listed terrestrial invertebrate insects, including pollinators, and/or modify their designated critical habitat from acute oral exposures to pesticides. The data will be used to reduce uncertainties associated with the risk assessment for terrestrial invertebrates and will improve EPA’s understanding of the potential effects on terrestrial species and whether there is a differential sensitivity of larval bees relative to adult bees. If acute oral effects data for larvae are not available, risks to terrestrial insects from acute oral exposure will be assu med How could the data impact the Agency’s future decision

- making? The data will inform the determination required under FIFRA or the ESA as to whether continued registration of a pesticide is likely to result in unreasonable adverse effects to non

- target species or is likely to adversely affect listed threatened or endangered species and/or modify their designated critical habitat. Without these data, EPA may need to presume risk which will limit the flexibility of pesticide products to comply with FIFRA and the ESA, and could result in use restrictions.

Study Title: Tier I

- Pollinator Chronic Oral Toxicity, Larvae Rationale for Requiring the Data Terrestrial invertebrates are likely to be impacted if exposed to pesticides in various use settings. Pesticide residues may be transferred to pollen and/or nectar of treated plants and subsequently brought back to the hive where larvae and pupae may be e xposed. Therefore, potential effects to developing bees could result from chronic oral exposure to pesticide residues. Available toxicity studies do not address possible chronic effects on brood (larvae and pupae) survival. Because of the potential for pollen and nectar to be contaminated with pesticide residues, and subsequently brought back to the hive, it is important to determine chronic larval/pupal toxicity and whether adult emergence is adversely affected. This study will provide information on w hether honeybee larvae differ in sensitivity from adult bees following chronic
exposure.

The Office of Pesticide Programs has made available a guidance regarding ecological testing for invertebrates with the honeybee. The guidance discusses Tier 1 laboratory

- based chronic oral toxicity studies of individual honeybee larvae as a critical compo nent of the screening

- level risk assessment process for examining potential risks from specific routes of exposure. The guidance can be found at: http://www2.epa.gov/pollinator

- protection/pollinator

- risk

- assessment

- guidance

. Additional information on larval honeybee toxicity repeat exposure test design can be found in the oECD draft guidance23

http://www.oecd.org/env/ehs/testing/Draft_GD_honeybees_rep_exp_for_2nd_CR_25_November_2013.p df

. Practical Utility of the Data How will the data be used? The Tier I chronic oral toxicity d ata on bee l arvae serve as a foundation for the screening

- level assessment of potential risk to non

- target organisms including federally listed threatened or endangered and non

- listed terrestrial invertebrate insects, including pollinators, from chronic oral exposures to pesticides. The data will be used to reduce uncertainties associated with the risk assessment for terrestrial invertebrates and will improve EPA’s understanding of the potential direct and indirect lethal and sublethal effects on a broad range of terr estrial species, particularly insect pollinators. These data will also assist in determining whether early life stages of the bee differ in their sensitivity to pesticides relative to adults. If chronic oral effects data for larvae are not available, ris ks to terrestrial insects from chronic oral exposure will be assumed. How could the data impact the Agency’s future decision

- making? The data will inform the determination required under FIFRA or the ESA as to whether continued registration of a pesticide is likely to result in unreasonable adverse effects to non

- target species or is likely to adversely affect listed threatened or endan gered species and/or modify their designated critical habitat. Without these data, EPA may need to presume risk which will limit the flexibility of pesticide products to comply with FIFRA and the ESA, and could result in use restrictions.

Study Title: Tier II Semi

- Field Toxicity Testing (tunnel/enclosure studies) Rationale for Requiring the Data Tier II studies are conditional on the outcome of the screening

- level assessment where acute and/or chronic risk levels of concern have been exceeded for ter restrial invertebrates. Terrestrial invertebrates are likely to be impacted if exposed to pesticides in various use settings. Pesticide residues may be transferred to pollen and/or nectar of treated plants and subsequently brought back to the hive and ma y adversely affect developing brood (egg, larvae, and pupae) and adult bees . Screening

- level (Tier I) studies of individual bees do not address possible effects and/or exposure to pesticide residues at the colony

- level. Because of the potential for polle n and nectar to be contaminated with pesticide residues, and subsequently brought back to the hive, it is important to determine whether bee colonies may be negatively affected under relatively controlled exposure conditions of a semi

- field study. In addit ion to providing effects data, these studies can provide data on exposure as pesticide residues in pollen/nectar of treated plants.

The Office of Pesticide Programs has made available a guidance regarding ecological testing for invertebrates with the hone ybee. The guidance describes the tiered testing process and can be found at: http://www2.epa.gov/pollinator

- protection/pollinator

- risk

- assessment

- guidance . Add itional information on honeybee colony studies under semi

- field conditions can be found in the OECD Guidance 75 http://www.oecd.org/ officialdocuments/publicdisplaydocumentpdf/?cote=env/jm/mono%28

. Practical Utility of the Data How will the data be used? Tier II colony

- level data will be used to assess potential risk to non

- target organisms including listed and

non

- listed terrestrial social invertebrate species and to determine whether effects observed in the screening

- level (Tier I) laboratory

- based studi es of individual bees are evident in colony

- level studies under semi

- field conditions. The Tier II semi

- field test of whole colonies is a relatively controlled study, i.e ., bees are confined to a specific area, that is designed to represent potential fiel d

- level exposure and account for hive dynamics, which are not achievable from other pollinator studies. This study will be used to determine24

whether adverse effects to insect pollinators at the whole colony level, may result for the use of pesticides and will help to refine risk estimates derived in the screening

- level risk assessment for beneficial terrestrial invertebrates. Measured residues in pollen/nectar can also be used to refine risk estimates derived from model

- based or default values in the scre ening

- level assessment.

How could the data impact the Agency’s future decision

- making? The data will inform the determination required under FIFRA or the ESA as to whether continued registration of a pesticide is likely to result in unreasonable adverse e ffects to non

- target species or is likely to adversely affect federally listed threatened or endangered species or their designated critical habitat. Without these data, EPA may need to presume risk which will limit the flexibility of pesticide products t o comply with FIFRA and the ESA, and could result in significant use restrictions.

Study Title: Tier II Semi

- Field Toxicity Testing (feeding studies) Rationale for Requiring the Data Pesticide residues may be transferred to pollen and/or nectar of treated plants and subsequently brought back to the hive, and may adversely affect developing brood (egg, larvae, and pupae) and adult bees . Tier II feeding studies are conditional on the outcome of the screening

- level assessment where acute and/or chronic risk levels of concern have been exceeded for terrestrial invertebrates based on Tier I studies of individual bees. Feeding studies utilize free foraging bee colonies that are “dosed” with specific quantities of test material and represent a means of ensu ring exposure to the test material through spiked pollen and/or sugar solutions fed to the colony while still allowing the bees to forage freely. Since bee colonies are not confined to enclosures, colonies can be exposed for longer duration periods withou t subjecting the bees to stress that typically results from Tier II tunnel studies. Available toxicity studies of individual bees (Tier 1) conducted to support screening

- level assessments do not address possible effects and/or exposure to pesticide residu es at the colony

- level. Because of the potential for pollen and nectar to be contaminated with pesticide residues, and subsequently brought back to the hive, it is important to determine whether bee colonies may be negatively affected where bees are free foraging and have the option to collect/consume alternative forage items beyond the spiked food. Since multiple dose levels can be more readily tested, feeding studies can help to define dose

- response relationships at the whole colony level.

The Office of Pesticide Programs has made available a guidance regarding ecological testing for invertebrates with the honeybee. The guidance describes the tiered testing process and can be found at: http://www2.epa.gov/pollinator

- protection/pollinator

- risk

- assessment

- guidance . Additional information on honeybee colony feeding studies can be found in the EPPO Guidance 170 at: http://www.nationalbeeunit.com/index.cfm?pageId=187

. Practical Utility of the Data How will the data be used? Tier II colony feeding data will be used to assess potential risk to non

- target organisms including listed and

non

- listed terrestrial social invertebrate species. The colony feeding study is designed to represent potential field

- level exposure and account for hive dynamics using longer duration exposure periods than are possible in Tier II tunnel studies. The study will be used to determine whether potential adverse effects to insect pollinators at the whole colony level when bees are able to forage natur ally beyond the spiked food. Results from the feeding study will help to refine the screening

- level risk assessment for beneficial terrestrial invertebrates that were based on Tier I studies on individual bees. Since feeding studies can help to define a dose

- response relationship at the colony level, the studies can provide a means of determining exposure thresholds below which the likelihood of adverse effects on colonies may be low.25

How could the data impact the Agency’s future decision

- making? Tier I I colony

- level data will be used to refine screening

- level risk estimates derived using Tier I laboratory

based data on individual bees. The Tier II data will inform the determination required under FIFRA or the ESA as to whether continued registration of a pesticide is likely to result in unreasonable adverse effects to

non

- target species or is likely to adversely affect federally listed threatened or endangered species or their designated critical habitat. Without these data, EPA may need to presume ris k which will limit the flexibility of pesticide products to comply with FIFRA and the ESA, and could result in significant use restrictions.

Study Title: Residues in Pollen and Nectar Rationale for Requiring the Data Terrestrial invertebrates are likely to be impacted if exposed to pesticide residues in various use settings. Pesticide residues may be transferred to pollen and/or nectar of treated plants and subsequently brought back to hive where all life stages may be exposed. For some pesticide s, the quantification of pollinator

relevant residues in treated flowering plants is needed, since pollinators will be exposed to residues from either current or prior season applications (due to the potential for residues to accumulate in plants and
trees ). Residues in edible/transportable

- to

- hive parts of treated trees and plants, including (where appropriate), but not limited to, guttation water, sap/resins, whole plant tissue ( e.g., leaves, stems), as well as blooming, pollen

- shedding, and nectar produ cing parts ( i.e. , flowers and, if present, extra

- floral nectaries) of plants may inform the potential for risk. Studies should be designed to provide residue data for crops and application methods of concern.

The Office of Pesticide Programs has made available a guidance regarding ecological testing for invertebrates with the honeybee. The guidance can be found at: ht tp://www2.epa.gov/pollinator

protection/pollinator

- risk

- assessment

- guidance

. Practical Utility of the Data How will the data be used? Measured residue d ata will be used to refine conservative estimates of pesticide exposure and reduce uncertainties assoc iated with the Tier I exposure assessment by providing direct measurements of pesticide concentrations resulting from actual use settings. Measured residues may provide a more realistic understanding of exposure through contact or ingestion with which to calculate risk quotients for individual bees as well as to characterize exposure to the colony. If measured residue data are not available, risk estimates for terrestrial insects will be based on model

- generated or default values used to support the

scree ning

- level assessment.

How could the data impact the Agency’s future decision

- making? The data will inform the determination required under FIFRA or the ESA as to whether continued registration of a pesticide is likely to result in unreasonable adverse effects to non

- target species or is likely to adversely affect federally listed threatene d or endangered species or their designated critical habitat. Without these data, EPA will have to rely on conservative estimates of exposure which will limit the flexibility of pesticide products to comply with FIFRA and the ESA, and could result in use restrictions.26

10. Bibliography

Allen, T.C., Link, K.O., Ikawa, M., Brunn, L.K. 1945. The relative effectiveness of the principle alkaloids of the sabadilla seeds. Journal of Economic Entomology. 38: 293

- 296. Bergmann, E.D., Levinson, A.H., Mechoulam, R. 1958. Toxicity of Veratrum and So lanum alkaloids to housefly larvae. J. Insect Physiology 2(162): 162

- 177.

Catterall W.A. 1975

. Activation of the action potential Na+ ionophore of cultured neuroblastoma cells by veratridine and batrachotoxin . J. Biol. Chem. 250: 4053

– 4059.

Hare, J.D. and Morse, J.G. 1997. Toxicity, persistence and potency of sabadilla alkaloid formulations to citrus thrips (Thysanoptera: Thripidae). Journal of Economic Entomology. 90(2): 326

- 332.
Humeres, E.C., Morese, J.G. 2006. Resistance of avocado thrips ( Thysanop tera: Thripidae ) to sabadilla, a botanically derived bait. Pest Management Science 62: 886

- 889.
Ikawa, M., Dicke, R.J., Allen, T.C., Link, K.P. 1945. The principle alkaloids of sabadilla seed and their toxicity to Musa domestica. Journal of Biological Che mistry 159: 517

- 524.
McKinney, L.C., S. Chakraverty, P. De Weer. 1986. Purification, solubility, and pKa of veratridine. Analytical Biochemistry 153: 33

– 38.
Metcalf, R.L. 1995. Kirk Othrner Encyclopedia of Chemical Technology. Kroschwitz J.I. Ed. Vol 14 . pp 524

- 602. John Wiley and Sons, New York, NY

. Pelletier, P.J. and Caventou, J.B. 1819. Unnamed article. J. Phys. Chim. Hist. Nat. et Arts. 89: 155.

Pelletire, S.W. and Jacobs, W.A. 1953. The veratrine alkaloids XXXV. Veracevine, the alkanolamine of cevadine and veratridine. Journal of American Chemical Society. 75: 3248

- 3252.

Pesticide Action Network. 2012. Pesticide Database

– California Pesticide Use for sabadilla alkaloids. http://www.pesticideinfo.org/List_CA_Chem_Use.jsp?chk=521&cok=00&sk=00
Tomlin, C. 2003. The Pesticide Manual, a World Compendium. 13th ed. D.S. Ed. The BritishCrop Protection Council

.
USEPA 2004 a

. Reregistration Eligibility Decision Exposure and Risk Assessment on Lower Risk Pesticide Chemicals Sabadilla Alkaloids (RED)

. September 27 , 2004. http://www.epa.gov/pesticides/chem_searc h/reg_actions/reregistration/red_PC

- 002201_27

- Sep

- 04.pdf

USEPA. 2004 b . Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs. U.S. Environmental Protection Agency, Office of Prevention, Pesticides and Toxic Substances, Offi ce of Pesticide Programs, Washington DC. January 23, 2004.
USEPA. 2014a. Sabadilla (002201): Screening Level Usage Analysis (SLUA). Biological and Economic Analysis Division, Office of Pesticide Programs. December 4, 2014.

USEPA. 2014 b . Toxicity Testing an d Ecological Risk Assessment Guidance for Benthic Invertebrates. Environmental Fate and Effects Division, Office of Pesticide Programs. April 10, 2014.
Walton, R.R. 1947. Effects of chlorinated hydrocarbons and sabadilla on insects and plants. Journal of
E conomic Entomology. 40: 389

- 395.