Page 2 of 7



### Proposed Registration Decision for a Product Containing the New Active

Ingredient , Cuprous Iodide

Summary

T he U.S. Environmental Protection Agency (EPA) is proposing to register a new end

- use product, Cupron Cuprous Iodide, comprised of a new active ingredient, cuprous iodide, under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) , as amended

.

Cuprous iodide is an inorganic compound propos ed to be formulated into an end

- use product for material preservation of fibers ; floor coverings; plastics, coatings, films, and laminates; and adhesives and sealants to control the growth of algae, mold, mildew, fungi and bacteria which cause unpleasant o dors, discoloration, staining, deterioration, or corrosion

.

Background

On July 25, 2012, EPA received an application f rom Cupron Inc to regist er a n end

- use product containing the new active ingredient, cuprous iodide (CAS Number 7681

- 65

- 4 ), for material preservation . The company submitted product chemistry, toxicology, human exposure, ecological effects, and environmental fate data in support of its application for registration of the

one end

- use product containing the new active ingredient

.

During th e application screening, the Agency determined that additional product chemistry data needed to be submitted to confirm the applicant’s assertion that the manufacturing process does not produce cuprous iodide with nanochemistry attributes . B ased on additio nal information submitted by the applicant, the Agency determined that the active ingredient was appropriately identified as cuprous iodide and should not be identified as nano cuprous iodide.

In November 2014, the Agency determined the proposed formulati on posed inhalation handler risks that could only be mitigated through reformulation. In March 2015, Cupron submitted a revised application that included a new confidential statement of formula and product chemistry data reflecting the product’s reformula tion from a powder to a masterbatch. A masterbatch is a

common industrial term utilized when an a ctive ingredient is imbedded in to non

- friable plastic pellets which are then incorporated into manufactured products

.

The application is for an end

- use pro duct to be used as a materials preservative at a rate of 0.2% to 5.0% by weight in the final article. The articles proposed to be treated are listed in Table 1

.Page 3 of 7 Table 1

- Proposed Uses of Cuprous Iodide

Use Group Specific Uses

Fibers Household items (bedding, mattress cover pads, sheets, blankets, towels) Upholstery Carpet overlay and backing Conveyor Belts (non

- food contact) Automotive and truck upholstery and carpeting truck liners, convertible tops and liners Apparel including outwear, sportswear, sleepwear, undergarments, and socks Floor coverings Carpets, rugs, and mats Plastics, coatings, films, and laminates Automotive and vehicular parts Building materials and components Wood and plastic compo sites (non

- food contact) Countertops (non

- food contact)

Indoor furniture Floor covering and flooring Personal hygiene (combs, brushes, hairclips) Fire system sprinkler pipe coatings (inside surfaces)

Adhesives and

Sealants Adhesives used in wood and plastic composites Adhesives for ceramic tile, rubber, and plastic Window glazing, grout

Public Comments

As required by FIFRA, the Agency published a notice of rece ipt of applications to register a

p esticide product containing the new acti ve ingredient , cuprous iodide in the Federal Register on

October 30 , 20 13 (7 8 FR 2 5596) , and a 30 day public comment period commenced. One

comment from the Bay Area Clean Water Agencies was received in response to the Federal Register notice.

The comment expressed concern s about the potential impact copper iodide and copper could have to aquatic life from release to w astewater treatment facilities and to the aquatic

environment

.

In response to this comment, the Agency refers to the August 2 5 , 2015 risk assessment entitled,

“ Human Health and Ecological Risk Assessment for Cuprous Iodide

. ” As part of the risk assessment, the Agency conducted a screening level “down the drain” assessment t hat estimates the number of days per year of exceedance of conc entrations of concern (COCs) for freshwater aquatic organisms downstream of domestic wastewater treatment plants that receive influent from institutional facilities, commercial establishments, and residences that discharge leachate from washing fabrics tre ated with cuprous iodide. No acute COCs were exceeded for copper, iodine, or cuprous iodide for one or more days for either the screening average case scenario or

the screening high

- end scenario for non

- listed aquatic organisms. For copper at the screening high end scenario, listed/endangered freshwater invertebrates COCs were exceeded for up to 72 days for copper and 12 days for copper iodide. For the screening average case scenario, the

exceed a nces for endangered/listed freshwater invertebra tes were 8 days for copper and 1 day for copper iodide. No chronic COCs were exceeded for 20 days or more for copper ion, and potential chronic risks from exposure of aquatic freshwater organisms to iodine and cuprous

iodide are expected to be negligible.Page 4 of 7

In addit ion to the Cuprous Iodide Risk A ssessment

, c opper is undergoing r egistration r eview

, and the preliminary risk assessment will be available for comment in March 2016

. Registration review is a program intended to make sure that, as the ability to assess risk evolves and as policies and actives change, all registered pesticides continue to meet the statutory standard of no

unreasonable adverse effects to human health and the environment. Chemicals are re

- evaluated

on a 15

- year cycle.

The Agency is now seeking public comment under the public participation process, FIFRA section 3(c)(4), for th is proposal to issue an unconditional registration for the proposed cuprous iodide product.

Evaluation

In evaluating a pestici de registration application, the EPA assesses a wide variety of exposure information, ( i.e., where and how the pesticide is used), 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 the likelihood of adverse effects ( i.e., risk) from exposures associated with the proposed use of the product. Risk assessments are developed to evaluate the environmental fate of the compound as well as how it migh t affect a wide range of non

- target organisms including humans, terrestrial and aquatic wildlife (plants and animals). On the basis of these assessments, EPA evaluates and approves language for each pesticide label to ensure the

directions for use and saf ety measures are appropriate to mitigate the potential risk. The pesticide’s label communicate s directions for use that are necessary for public safety. It is a

FIFRA violation to use a registered pesticide in a manner inconsistent with its label ing

.

1. Ass essment of Risk to Human Health

EPA requires a wide range of studies in order to assess a pesticide. T he human health effects and risk of cuprous iodide, as assessed in the August 2 5 , 2015 document entitled, “ Human Health and Ecological Risk Assessment fo r Cuprous Iodide ” are summarized below. The Agency has determined that exposure to cuprous iodide via the oral (water) or dermal route is primarily to copper and iodine ions , not cuprous iodide

. Because cuprous iodide is formulated as a master batch, which consists of the a.i. imbedded in non

- fr iable plastic pellets, the inhalation exposure is negligible and thus an inhalation assessment is not needed

. Therefore, the cuprous iodide human health risk assessment evaluates copper and iodine ions only via the oral and dermal route. The toxicology database to assess cuprous iodide is adequate to support the antimicrobial pesticidal

uses of this chemical.

The copper toxicity database is robust and t he A gency has no concerns for systemic toxicity

from human exposure to copper (Reregistration Eligibility Decision Document for Coppers, 2009). Therefore, the toxicology assessment for cuprous iodide is based on data f rom the iodine toxicity database

. Three human studies from the open literature examining oral and systemic toxicity of iodine were presented to the Human Studies Review Board in June 11, 2014 for review of the ethics and science and were found acceptable for use in regulatory decisions. The

data from these three studi es indicate that the target organ for iodine toxicity in the human is the thyroid . The incidental oral and dermal iodine endpoints are based on the thyroid.Page 5 of 7

Additional toxicity data for either the copper or iodine are not neede d for the cuprous iodide risk

assessment. Carcinogenicity

, neurotoxicity , or immunotoxicity data are not needed for either copper or iodine since the cuprous iodide hazard assessment is based on effects of t he human thyroid. Data also demonstrate that the iodine component of cuprous iodide is not a developmental or reproductive toxicant (Reregistration Eligibility Decision Document for Iodine, 2006). The Agency granted data waiver requests for a mutagenicity battery conducted with iodine for oral exposures to this chemical (Memorandum: from S. Diwan to J. Smith and M. Rice, 12/96)

.

Toxicity endpoints were selected for iodi n e to perform exposure and risk assessments for

incidental oral and dermal exposure (see Table 2)

. A short

- term incidental o ral endpoint was selected to be protective of children sucking on treated articles

. A d ermal endpoint was selected

to assess exposures to iodine that may occur from dermal contact with materials treated with cuprous iodide. A dermal absorption factor of 0.1% was used to account for the oral endpoint. Because cuprous iodide is formulated as a master b atch, which consists of 20 percent a.i.

imbedded in non

- friable plastic pellets, there is n egli gi ble potential for inhalation expo sure and thus no inhalational endpoints are selected.

Table 2

- Summary of Toxicological Endpoints for Iodine
Exposure

Scenario Dose Used in Risk

Assessment UF and Target MOE Study and Toxicological

Effects

Incidental Oral

Short

- Term (1

- 30 days) and

Intermediate

- Term (1

- 6 months) NOAEL = 1.5 mg/day UF ( i.e., target MOE)

Residential = 1 Occupational = N/A Human Oral Study (MRID 48358603)

LOAEL > 1.5 mg/day

Dermal

Short

- Term NOAEL = 1.5 mg/day

Dermal absorption

factor = 0.1% UF ( i.e., target MOE)

Occupational = 1

Residential = 1 Human Oral Study (MRID 48358603)

LOAEL > 1.5 mg/day

Dermal absorption by miniature pigs ( MRID 49342401) UF = uncertainty factor, NOAEL = no observed adverse effect level, LOAEL = lowest observ ed adverse effect

l evel, MOE = margin of exposure, RfC = reference concentration

Dietary exposure to copper iodide as a result of residues from the treated article s is not expected

based on the label that would restrict application to nonfood contact plastics, laminates, and coating for countertops and conveyor belts. However, there could be exposure to copper iodide as a result of residues in drinking water, but exposure is expected to be low based on limited leaching from textiles as demonstr ated in the cuprous iodide textile leaching study (M. Brooks, MRID 49200001)

. Therefore, there are no dietary concerns from food or drinking water from the proposed uses of cuprous iodide.

There are potential residential post application exposure and ri sk to human s who may be exposed to cuprous iodide fibers that could be used to manufacture household items such as blankets, towels, and apparel such as sleepwear. Given these proposed uses, dermal exposure to adultsPage 6 of 7

and children who wear treated clothing and incidental oral exposure to toddlers who chew on blankets, towels

, and clothing were assessed. All residential risk estimates were below EPA’s

level of concern.

Since cuprous iodide is formulated as a masterbatch which consists of 20 percent a.i. im bedded

in non

- friable plastic pellets, the exposure is n egligible and thus an occupational risk assessment is not required.

The acute toxicity of cuprous iodide falls in the lowest acute toxicity categories of III (oral, inhalation, primary eye irritation) and IV (dermal and primary dermal irritation). Thus, the

labe ling precautionary signal word is “CAUTION.”

2. Assessment of Ecological Risk

The battery of tests required to assess the ecological risks and environ mental fate of cuprous iodide is complete. T he environmental fate and ecological risks of cuprous iodid e a ssessed in the document entitled, “ Human Health and Ecological Risk Assessment for Cuprous Iodide ” are summarized below.

Cuprous iodide is slightly toxic to birds and highly toxic to aquatic invertebrates. Thus, the environmental hazard labeling statement, “this pesticide i s toxic to aquatic organisms,” is required on the label.

The value of the maximum annual production volume of cuprous iodide was assumed to be 77,000 kilograms per year (170,000 pounds). For copper ion, the percent removal during wastewater treatment was assumed to be 84.2 percent (EPA, 2000). For iodine and copper iodide, in the absence of data on removal during wastewater treatment, EPA conservatively assumed that there would be no removal during wastewater treatment.

The primary pathway by which cuprous iodide would be expected to be released into the aqua tic environment is by the leaching of cuprous iodide during in

- service use of manufactured products ( i.e., fabric washing at institutional facilities, commercial establishments, and residences). A fabric leaching study showed that when woven (polyester) and non

- woven (polyethylene) treated fabrics were soaked and agitated to simulate a washing machine cycle, limited leaching occurred.

Since cuprous iodide will dissociate in water, exposure of o rganisms to discharge water reaching the aquatic environment will be predominantly to copper and iodine ions. Therefore, the ecotoxicity endpoints for the ecological risk assessment were obtained from the copper iodide as

well as the copper and iodine dat abases.

A screen ing level down the drain assessment estimates the number of days per year of exceedance of concentrations of concern (COCs) for freshwater aquatic organisms downstream of domestic wastewater treatment plants that receive influent from i nstitutional facilities, commercial establishments, and residences that discharge leachate from washing fabrics treated with cuprous iodide. Estimates of exposure were developed using 7Q10 stream flow which is

the lowest 7 consecutive

- day stream flow over a 10

- year period.Page 7 of 7

Generally, for any assessment, if the probabilistic modeling predicts the acute COC is exceeded for one day or more , potential acute risks may be expected. No acute COCs for copper, iodine, or cuprous iodide exceeded for one day or m ore for either the average case scenario or the high

end scenario for aquatic organisms.

Further, if the chronic COC (i.e., NOAEC) determined for any key aquatic receptor group is exceeded for more than 20 days , potential chronic risks may be expected. No chronic COCs

were exceeded for 1 day for copper ion. There were no chronic endpoints for iodine or cuprous

iodide ; however, even if equal toxicity to copper was assumed, no exceedances would be

pre dicted by the DTD modeling Consequently, potenti al chronic risks from exposure of aquatic freshwater organisms to iodine and cuprous iodide would be expected to be negligible

.

Proposed Regulatory Decision

Under Section 3(c)(5) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the Agency is proposing to un conditional ly regist er a new end

- use product, Cupron Cuprous Iodide, comprised of a new active ingredient, cuprous iodide. The proposed registration is summarized

below.

84542

- O ( Cupron Cuprous Iodide )

 20% cuprous iodide

 E nd

- use P roduct

, a material preservative to be incorporate d into manufactured products to control the growth of algae, mold, mildew, fungi, and bacteria which cause unpleasant odors, discoloration, staining, deterioration, or corrosion.

The risk assessment supporting this decision can be found in the regulatory docket (Docket ID:

EPA

- HQ

- OPP

- 2013

- 0433).

Public Participation

FIFRA requires public participation in the pesticide registration process for new active ingredients under Section 3(c)(4). The Agency explored opportunities for expanding the openness of the process for new active ingredients and other registration actions. In October 2009, the Agency began implementing a public participation process for certain pesticide registration actions, including registration of products containing a new active ingredient, http://www.epa.gov/pesticides/regulating/public

- participation

- process.html

.

The Agency will consider a ll public comments received during the public comment period for

this proposal to issue an un conditional registration for the proposed cuprous iodide product. During the public comment period, comments should be submitted under Docket ID No. EPA

HQ

- OPP

- 20 13

- 0433 via www.regulations.gov , mail, or hand delivery.