## Registration Decision for the Residential Use of Spirotetramat

on Citrus

U.S. Environmental Protection Agency Office of Pesticide Programs Registration Division

Approved by:

_ Susan Lewis , Director Registration Division

Date: January 19, 20162 

### Registration Decision for Spirotetramat on Citrus Trees G rown in Residential Areas, the First Residential Use for the Active Ingredient Spirotetramat

Summary

The U.S. Environmental Protection Ag ency (referred to hereafter as EPA) is unconditionally registering a new product containing the active ingredient spirotetramat under section 3(c)(5) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA)

. The product is for use only on citrus trees grown in residential areas.

Spirotetramat is currently registered for use on ornamentals (ex. Christmas trees) and agricultural crops such as banana s
, citrus

, coffee, hops, pineapple, apples, pears

, grapes
, cherries, peaches , tree nuts, tomatoes, pepper s
, celery, spinach, lettuce

, peas, lentils

, potato es , and watercress.

The new product, “ 14ACP703 SC Insecticide/Miticide

, ” is a soluble concentrate liquid

formulation containing 22.4% spirotetramat

. The main target pest is Asian citrus psyllid

. The produ ct is intended for use by commercial licensed applicators and the instructions for use are based on applications made using commercial equipment (spray tanks with agitators). The application rates are expressed in ounces of product per acre , or ounces

per 100 gallons of water, and not in terms of hose

- end sprayers or other types of equipment used by the general consumer.

The application rates and restrictions for t his proposed use of spirotetramat on residential

sites are identical to the currently reg istered agricultural use on citrus.



### Requested Action

On September 10 , 2014, EPA received an application from Bayer Environmental Science

to register a new end

- use product containing spirotetramat ( CAS Number: 203312

- 25

- 1 )

, for use on citrus trees grown in residential areas

. This action represents the first time EPA has considered a residential use involving spirotetramat. Per EPA’s policy to seek public comment on key proposed regulatory actions, EPA opened a 30

- day publ ic comment period on its regulatory position on December 9, 2015

.



### Evaluation

When evaluating a n application for a pesticide registration, t he EPA assesses a wide variety of exposure information . This includes where and how the pesticide is used

, the environmental fate ( i.e ., how the chemical will move in the environment) and toxicity studies ( i.e ., effects on humans and other non

- target organisms) to determine the3 likelihood of adverse effects ( i.e ., risk) from exposures associated with the proposed u se of the product. Risk assessments are developed t hat evaluate the environmental fate of the compound

, as well as how it might affect a wide range of non

- target organisms

, including humans and terrestrial and aquatic wildlife (plants and animals )

. On the basis of these assessments, EPA evaluates and approves language for pesticide label ing to ensure the directions for use and safety measures are appropriate to mitigate potential

risk s . In this way, each pesticide’s label ing helps to communicate essen tial limitations and mitigations that are necessary for public safety. It is a FIFRA violation to use a pesticide in a manner inconsistent with its label ing

.

1. Assessment of Risk to Human Health

For the use of spirotetramat on citrus trees in residential sites, the database of studies required to support the assessment of risk to human health is complete.

Table 1 summarizes the toxicological endpoints used in the human health risk

assessment. T he acute dietary endpoint is based on clinical signs and decreased motor activity observed in the acute neurotoxicity study in rats. The chronic dietary endpoint is based on the thymus involution in males in the chronic dog study.

Table 1.

-- Summary of To xicological Doses and Endpoints for Spirotetramat , for Use

in Human Health Risk Assessment

Exposure/Scenario Point of Departure and Uncertainty/Safety

Factors RfD, PAD,

LOC for Risk

Assessment Study and Toxicological

Effects Acute dietary (All populations) NOAEL = 100 mg/kg/day

UF A = 10x

UF H = 10x FQPA SF = 1x Acute RfD =

1.0 mg/kg/day Acute neurotoxicity study

– rat
LOAEL = 200 mg/kg/day Chronic dietary (All populations) NOAEL= 5 mg/kg/day

UF A = 10x

UF H = 10x FQPA SF = 1x Chronic RfD =

0 .0 5 mg/kg/day

cPAD = 0.05 mg/kg/day 1

- year oral toxicity study

dog

LOAEL= 2 0 mg/kg/day Cancer (Oral, dermal, inhalation) Spirotetramat is classified as “not likely to be carcinogenic to humans” based on data showing no treatment related increase in tumor incidence in rat and mouse carcinogenicity studies.

Abbreviations: UF = uncertainty factor, UF A = extrapolation from animal to human (interspecies), UF H = potential variation in sensitivity among members of the human population (intraspecies), FQPA SF = FQPA Safety Factor,

NOAEL = no

- observed adverse

- effect level, LOAEL = lowest

- observed adverse

- effect level, RfD = reference dose (a = acute, c = chronic), PAD = population

- adjusted dose, LOC = level of concern.

The evaluation of the chronic toxicity studies indicates that spirotetramat is not carcinogenic. EPA has not made a common mechanism of toxicity finding for spirotetramat and any other substances. This means that the available information4 support the conclusion that spirotetramat does not have a common mechanism of toxicity

with other substances.

The use on citrus tree s in residential sites did not require a reassessment of dietary

exposures since the use pattern is identical to the registered agricultural use pattern, and

is not expected to result in higher residues

. Given the low likelihood of adverse effects on humans, more refined estimates of acute and chronic dietary risk were not necessary for spirotetramat. The assessment incorporated the highest

- level residues on the commodities and default or empirical processing factors and conservative drinking water estimates of exposure. The dietary assessment also conservatively assumed that 100% of every crop was treated. Neither the acute nor the chronic dietary exposure and risk estimates exceed the Agency’s level of concern.

EPA aggregate s pesticide exposures and risks from three major sources: food, drinking water, and re sidential exposures. When aggregating exposures and risks from various

sources, EPA considers both the route and duration of exposure.

The acute aggregate risk assessment takes into account exposure estimates from dietary consumption of spirotetramat (fo od and drinking water). The acute dietary exposure

estimates are not of concern

.

Short

- term (1 to 30 day) and intermediate

- term (1 to 6 months) aggregate risk assessments are necessary for adults since there is potential for handler exposure from the

r esidential use of spirotetramat on citrus trees . Since the short

- term assessment assumed no dissipation (i.e., day

- zero residues) for the entire exposure duration (up to 30 days),

and the short

- and intermediate

- term points of departure (POD) are the same , the short

term assessment is expected to be protective of intermediate

- term exposure durations.

For the short

- term aggregate risk assessment, potential residential exposures were combined with food and drinking water exposures. Specifically, the shor t

- term aggregate assessment for adults combines dietary (food + drinking water) exposures with handler

inhalation exposures resulting from the proposed use

.

The short

- term residential exposure estimates were aggregated with the chronic dietary (food + dr inking water) to provide a worst

- case estimate of short

- term aggregate risk for

adults . As the short

- term aggregate margins of exposure are 1,900 and thus greater than

100 (the Level of Concern) , risk estimates are not exceed ed. Short

- term aggregate MOEs are protective of intermediate

- term exposure durations.

For the spirotetramat use on residential citrus trees, there is the potential for dermal exposure for adults and children; however, since there is no dermal POD, a quantitative

assessment of derma l risk is not necessary

. Additionally, although applications will be made only to the foliage of the trees, the label directs that children and pets be kept off treated areas until they are dry. Post

- application inhalation exposure is not of concern

due to the combination of low vapor pressure for spirotetramat ( 1.5 x 10

- 8 Pa at 25oC) and the expected dilution in outdoor air.5 The new formulation of spirotetramat (“14ACP703 SC Insecticide/Miticide”) has a low

acute toxicity profile . The acute oral, acute dermal and primary eye irritation studies meet the criteria for Toxicity Category III. The acute inhalation and primary dermal irritation studies meet the criteria for Category IV. The product is, however, a dermal sensitizer, th erefore the label includes a statement alert ing the user and requires personal protective equipment (long

- sleeved shirt and long pants and chemical

- resistant gloves).

The signal word for 14ACP703SC is “Caution.”

2. Assessment of Ecological Risk

The u se of spirotetramat on citrus trees specifically located on residential plots is identical to the use of spirotetramat on citrus in agricultural settings. The single and seasonal application rate are the same and the interval between applications is also the same. In 2012, EPA conducted an ecological assessment for the agricultural citrus use. Given that the use pattern and label restrictions are the same for agricultural citrus and residential citrus, a new ecological risk assessment was not conducted.

Spirotetramat has low volatility and undergoes rapid photochemical degradation. Environmental concentrations in air are expected to be minimal and long

- range transport is unlikely to occur.

Dissipation of spirotetramat in field trials was rapid with a dissipation half

- life in a range

of 0.3

– 1.0 day. Since almost no transfer of spirotetramat in soil layers below 15 cm was

o bserved in the submitted studies, and volatili ty is low, dissipation of spirotetramat is

considered more or less consistent with d egradation. No differences were observed between bare ground and cropped plots. Due to the short half

- life in soil, the potential of accumulation in soil and carry

- over of spirotetramat from one year to the next is considered negligible.

For the use of spirotetramat on citrus, t he acute and chronic risk to freshwater and

estuarine/marine fish is below the Agency’s level of concern

. The acute and chronic risk

to freshwater and estuarine/marine invertebrates is also below the level of concern . There

are no risks of concern for aquatic plants.

Spirotetramat is practically non

- toxic to birds and mammals on an acute basis and the risk

for both is below the Agency’s level of concern. A chronic risk for birds was assessed from crops with higher use rates tha n citrus and represents upper bound exposure scenarios. There is no chronic risk concern when using mean exposure values for these crops with the higher application rates. The level of concern is exceeded in limited circumstances, ie. when birds repeated ly consume food items that are contaminated. The

c hronic risk to mammals is below th e level of concern. There is no risk of concern for terrestrial plants.6 Spirotetramat has practically no acute toxicity to honey bees through oral or contact

exposure. Brood feeding studies and semi

- field studies have suggested, however, potential effects on honey bee brood. EPA has not concluded at this time that spirotetramat presents a chronic risk to bees but has addressed the potential risk with mitigation through label restrictions

.



### Alternatives

Spirotetramat targets piercing and sucking insects such as aphids, whiteflies and psyllids. The registered alternatives for backyard (ie. residential) citrus include organophosphates

such as malathion

, carbamates such as carbaryl and neonicotinoids such as imidacloprid. All of these are acutely toxic to honey bees. The organophosphate and carbamate chemical classes generally pose a greater risk to humans than does spirotetramat. Both

classes are unde rgoing cumulative risk assessments as required by the Food Quality

Protection Act.



### Benefits

As noted above, spirotetramat is an alternative to older chemistries

. It is an important pest management tool for the piercing / sucking insect spectrum since many of these pests (e .g

. whiteflies ) tend to develop resistance. Commercial citrus growers have reported that spirotetramat has been vital in their struggle against the Asian citrus psyllid (ACP) . This pest vectors Huanglongbing (HLB)

, also known as “Citrus Greening,” which is an invasive bacterium that is threatening the collapse of the U.S. citrus industry. Infected

trees cannot recover and growers must destroy them

. According to USDA’s “ National Agricul t ural Statistics Survey ,” 130,108 acres of citrus i n Florida were abandoned in

2015 1

. In addition to providing protection for citrus trees in non

- agricultural settings, the proposed use of spirotetramat will target ACP that may be harboring in these trees, thereby providing support to commercial citrus gr owers.

Other serious pests that damage citrus include California red scale, mealybugs and whiteflies. Spirotetramat is also effective against these pests. The Insecticide Resistance Action Committee (IRAC) has classified spirotetramat in IRAC Group 23 s ince the

chemical’s mode of action is by inhibit ion of lipid biosynthesis. With the new product registration, spirotetramat is the only insecticide with this mode of action that will be

available for use on citrus in residential sites. Thus, this use provides a new tool for protection of residential citrus trees against serious target pests, especially the Asian citrus psyllid.

1http://www.nass.usda.gov/Statistics_by_State/Florida/Publications/Citrus/aban/CitAA 15.pd7 

### Regulatory Decision

The Agency is unconditionally granting the regist ration of a new product containing the active ingredient spirotetramat, “14ACP703 SC Insecticide/Miticide

, ” under section 3(c)(5) of FIFRA This is the first use of spirotetramat in residential areas

. The use is

limited to citrus trees.

This product is identical in formulation to the currently registered product Movento ®

, EPA Registration Number 264

- 1 05 0. The new use pattern on citrus in resid ential areas is identical to the registered agricultural use pattern

.

Spirotetramat does not meet the risk criteria for classification as a Restricted Use pesticide. The use of “14ACP703 SC Insecticide/Miticide” on citrus in residential sites

, however, is labeled for use by commercial licensed applicators and the registrant does not

intend to sell it for use by the general consumer

. The Directions for Use are expressed in terms appropriate for commercial applicators, the application instructions are not typical

for an application of a pesticide by the public who generally do not have access to high volume equipment

.

Since citrus is attractive to pollinators, applications of spirotetramat are not allowed when the trees are in bloom. Honey bees forage for citrus pollen which is fed as bee bread to the larval bees (the brood). Removing this exposure route during this time protects the colony brood from potential risk. T he product label bears the following restriction:

“Do not apply this product within 10 days prior to bloom, during bloom, or until petal fall is complete.”



### Public Comments

Notice of Receipt

On February 4, 2014, EPA published a Notice of Receipt (NOR) in the Federal Register

of an application for registration of “14AC P703 SC Insecticide,” a product containing 22.4% spirotetramat to be used on citrus trees grown in residential areas , and announced a public comment period of 30 days. No comments were received in response to the

NOR.

Proposed Registration Decision

On D ecember 9, 2015, EPA posted the “ Proposed Registration Decision for the Residential Use of Spirotetramat on Citrus ” to the public docket (EPA

- HQ

- OPP

- 2014

- 0923) and announced a 30

- day public comment period . Two comments were received

. Both comments expres sed support for the registration. The comment submitted by the

Chairman of the Citrus Research Board stated : “The use of this material in the fight8 against the HLB Bacterium is of the utmost importance in our fight to save the California Citrus Industry.”



### Regulatory Rationale

Spirotetramat is an alternative to older classes of chemistries currently on the market for residential sites, including organophosphates, carbamates, pyrethroids and neonicotinoids. The mode of action against the target pests (ap hids, scales, leafminers, thrips, mealybugs, whiteflies and psyllids) is unique (inhibition of acetyl CoA carboxylase). No other insecticide with this mode of action is registered for use against pests infesting citrus grown outside of agricultural sites . The registration of spirotetramat will protect not only citrus trees growing in neighborhoods and other residential sites, but as noted above, will also be highly beneficial to commercial growers by targeting populations of pests harboring outside of th e orchards, especially the Asian citrus psyllid.

The risk assessments supporting this decision are located in regulatory docket EPA

- HQ

OPP

- 201 4

- 0 923

.