UN ITED STATES ENVIRONMENTAL PROTECTIO N AGENCY WASHINGTON D .C.
, 20460

PC CODE: 014901 & 000905 DP BARCODE: D419790 DATE: August 6, 2014 MEMORAND U M

SUBJECT: Preliminary Ecological Risk Assessment for the Registrat ion Review of Ye ll ow Mustard Seed (PC Code 0 1 4901) and Sodium Alpha Olefin

FROM: Sulfonate (PC Co d e

### 000905)**~ ~**  

# tJ**f) ~**  Nicholas Mastrota
, Ph.D., Wildlife Biologist

## ~ / 

## f t
James 

### K. Wolf
, Ph.D., Environmental Scientist 

## /(.lJfr'O
Environmental Risk Branch 3 Environmenta l Fate and Effects Division (7507P)

THRO U GH: Dana Spatz, Branch

# Chie~~~**~** .. 

## C.- 2.,0l '-\ Environmental Risk

### Branch~**------"'<~ ~**  Environmental Fate and Effects Division (7507P)

TO: Linda Arrington
, Branch Chief Shirley Keel
, Chemical Review Manager Risk Management and Impleme n tation Branch 5 Pes t icide Re -Evaluation Divisio n (7508P)

This memorandum summarizes the potential ecological risk of two active ingredients, yellow mustard seed (PC Code 014901) and sodium Cl4

- C16 alpha -o lefin sulfonate (PC Code 000905, CAS 68439-57-6), that are formulated together in only one registered pesticide product in the United States; the r odenticide V ARGON ( E PA Reg

. No. 87972

- 1 )

. In Canada
, this same product is registered with the name EXIT

. The product is used for control of the Richardson's ground squirrel 

### (Urocitellus richardsonii) and the Wy o ming ground squirre l 

### ( U rocitellus elegans). The product is injected under pressure , forming a f o am , into a closed burrow system. Ground squirrels in t he burrow are killed by asphyxiation. V ARGON contains 0.89% yellow mustard seed and 6.91% sodium a l pha-olefin sulfonate. N either of these ingredients are lis t ed as active ingredients in any ot h er pestic i de product regis t ered in the United State s

.

The Environmental Fa t e and Effects Di v ision completed an ecological risk and drinking water assessment f or the Se c tion 3 registra t ion of these two active ingredients on December 12, 2002 (D286494). The only ecological risk identified for this product was the chance that non

- target animals may be impac ted if they are presen t in the burrow at the time of treatm e nt. There was particular concern no t ed for the western burro w ing owl 

### (Athene cunicularia hypogea)

, sinc e this owl wi ll ne s t in burrows dug b y other animals. The burrowing owl is not listed as t hreat ened or endangered in the United States. B ased on recommendations made in this risk assessment , the

### 2 following precautionary label statement was added to mitigate risk to non-target animals which may be present in the burrow:

“This product will suffocate all organisms within the treated burrow. Do 

### not apply where there is evidence that the burrow may be o ccupied by species other than Richardson’s ground squirrels and Wyoming ground squirrels.”

The risk assessment conducted in 2002 was qualitative , as the only hazard this product presents is from asphyxiation. Neither of the active ingredients are expectedto have significant toxicity. Mustard seed is a natural product that is widely consumed as an ingredient in condiments (mustards) and as a spice (dry mustard). Sodium alpha-olefin sulfonate is a surfactant that is widely used as an ingredient in shampoos, soaps, and cosmetics. Little or no exposure is expected to occur to animals that are not in the burrows at the time of treatment. The assessment also notes this control method would not result in carcasse s of ground squirrels withtoxic tissue residues, and therefore would not pose any secondary poisoning risk to predatory animals.

The previous assessment also concluded that surface and ground water exposure would be low based on environmental fate info rmation and the use pattern.

No changes in use pattern, science policy, or available data have occurred since the 2002 assessment that would change the risk conclu sions. In addition, no ecological incidents associated with either of these active i ngredients have been reported to the EPA 1 

### . Therefore, the 2002 assessment can be relied upon for the Registration Review of yellow mustard seed (PC Code 014901) and sodium C14-C16 alpha-o lefin sulfonate (PC Code 000905).

Effects on Threatened and Endangered Species

In November 2013, the EPA, along with the U.S. Fish & Wildlife Service (USFWS), the National Marine Fisheries Service (NMFS) (collectively, the Services), and the U.S. Department of Agriculture (USDA) released a summary of their joint Interim Approaches for assessing risks to listed species from pesticides. The Interim Appro aches were developed jointly by the agencies in response to the National Academy of Sciences ’ (NAS) recommendations and reflect a common approach to risk assessment sharedby the agencies as a way of a ddressing scientific differences between the EPA and the Services. The NAS reportoutlines recommendations on specific scientific and technical issues related to the de velopment of pesticide risk assessments that EPA and the Services must conduct in connection withtheir obligations under the Endangered Species Act (ESA) and FIFRA.

The joint Interim Approaches were released prio r to a stakeholder workshop held on November 15, 2013. In addition, the EPA presented the jo int Interim Approaches at the December 2013 Pesticide Program Dialogue Committee (PPDC) and State-FIFRA Issues Research and Evaluation Group (SFIREG) meetings, and held a stakeholder workshop in April 2014, allowing additional opportunities for stakeholders to comment on the Interim Approaches. As part of a phased, iterative process for developing the Interim Appro aches, the agencies will also consider public

1 The Ecological Incident Information System (EIIS) and the Aggregate Summary component of the Incident Data System (IDS) were queried on July 22, 2014.

### 3 comments on the Interim Approaches in conn ection with the development of upcoming Registration Review decisions. The details of the joint Interim Approaches are contained in the white paper “Interim Approaches fo r National-Level Pesticid e Endangered Species Act Assessments Based on the Recommendations of the National Academy of Sciences April 2013 Report,” dated November 1, 2013.

Given that the agencies are continuing to develo p and work toward implementation of the Interim Approaches to assess the potential risks of pesticides to listed sp ecies and their designated critical habitat, this preliminary risk assessment does no t contain a complete ESA analysis that includes effects determinations for specific listed species or designated critical habitat. Although EPA has not yet completed effects determinations for spec ific species or habitats, for this preliminary assessment EPA conducted a screening-level assessment for all taxa of non-target wildlife and plants that assumes for the sake of the assessment that listed species and designated critical habitats may be present in the vicinity of the application. This screening level assessment will allow EPA to focus its future evaluations on the types of species where the potential for effects exists once the scientific methods being develope d by the agencies have been fully vetted. Once the agencies have fully developed and implemented the scientific methods necessary to complete risk assessments for endangered and threatened (listed) species and their designated critical habitats, these methods will be applied to subs equent analyses for yellow mustard seed and sodium C14-C16 alpha-olefin sulfonate as part of completing this re gistration review.