UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, DC 20460

			OFFICE OF  PREVENTION, PESTICIDES,  AND TOXIC SUBSTANCES

 

December 1, 2007

MEMORANDUM:

Subject:		Occupational and Residential Dietary and Non-dietary Exposure
Assessments of Organic Acid Esters of Phosphoric Acid for the
Reregistration Eligibility Decision (RED) Document

To:			Heather Garvie, Chemical Review Manager,

			Regulatory Management Branch II

Antimicrobials Division (7510P)

From: 			Cassi Walls, Ph.D., Chemist

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

Thru:			Norm Cook, Branch Chief

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

DP Barcode: 		

Chemical Name:	Phosphoric acid, mono (2-ethylhexyl) ester, 

			Ethanol, 2,2’-(cocoimino)-bis, salt with Phosphoric acid, bis
(2-ethylhexyl) ester (1:1), and

			Ethanol, 2,2’-(cocoimino)-bis, salt with Phosphoric acid, mono
(2-ethylhexyl) ester (1:1)

		

PC Code:		111286, 129079, 129080 

CAS Registry No. 	1070-03-7, 68649-38-7, 120579-32-0TABLE OF CONTENTS

EXECUTIVE SUMMARY	3

1.0  INTRODUCTION	3 tc \l1 "1.0	INTRODUCTION 

1.1  Purpose	3

1.2  Criteria for Conducting Exposure Assessments	7

1.3  Chemical Identification	7 

1.4  Physical/Chemical Properties	7 

2.0  USE INFORMATION	7 tc \l1 "2.0	USE INFORMATION 

2.1  Formulation Types and Percent Active Ingredient	7 tc \l2 "2.1	
Formulation Types and Percent Active Ingredient 

2.2  Summary of Use Pattern and Formulations	9

3.0  SUMMARY OF TOXICITY DATA	9 tc \l1 "3.0	SUMMARY OF TOXICITY CONCERNS
RELATING TO EXPOSURE 

3.1  Acute Toxicity	9

3.2  Summary of Toxicity Endpoints	11

4.0  RESIDENTIAL EXPOSURE ASSESSMENT	11 tc \l1 "4.0	RESIDENTIAL EXPOSURE
ASSESSMENT  

4.1  Summary of Registered Uses	12

4.2  Dietary Exposure	12 tc \l2 "4.2	Dietary Exposure/Risk Pathway  

4.3  Drinking Water Exposure	12 tc \l2 "4.3	Drinking Water Exposure/Risk
Pathway  

4.4  Residential Exposures	12 

4.4.1  Residential Handler Exposures	13

4.4.2  Residential Post-application Exposures	15

4.4.2.1  Carpet Shampoo	16

4.4.2.2  Treated Vinyl	20

4.4.2.3  Textiles (Clothing)	23

4.4.2.4  Mattresses	26

4.4.3  Data Limitations/Uncertainties	28

5.0  RESIDENTIAL AGGREGATE RISK ASSESSMENT AND CHARACTERIZATION	29 tc
\l1 "5.0	RESIDENTIAL AGGREGATE RISK ASSESSMENTS AND RISK
CHARACTERIZATION 

5.1  Acute and Chronic Dietary Aggregate Risk	29

5.2  Short and Intermediate Term Aggregate Risk	29

6.0  OCCUPATIONAL EXPOSURE ASSESSMENT	29 tc \l1 "6.0	OCCUPATIONAL
EXPOSURE AND RISK 

6.1  Summary of Registered Uses	29

6.2  Occupational Handler Exposures	32

6.3  Professional Painter	33

6.4  Occupational Post-application Exposures	33 tc \l2 "6.3	Occupational
Post-application Exposures 

6.5  Data Limitations/Uncertainties	33 tc \l2 "6.8	Data
Limitations/Uncertainties 

7.0  REFERENCES	35 tc \l1 "7.0	REFERENCES  

 tc \l2 "6.2	Occupational Handler Exposures 

EXECUTIVE SUMMARY tc \l1 "EXECUTIVE SUMMARY 

		The Antimicrobials Division (AD) prepared occupational and residential
dietary and non-dietary exposure assessments for the inclusion in the
Organic Acid Esters of Phosphoric Acid (referred to as Intersept ai in
the remainder of this document) Reregistration Eligibility Decision
(RED) Document.  It addresses the potential risks to humans that result
from the use of this chemical in occupational and residential settings. 

Currently, Intersept is used as a materials preservative (Use Site
Category VII) for carpet backing, vinyl products, textiles, mattress
covers and ticking, plastics, polymers, adhesives and caulks, and
coatings such as water-, oil- and solvent-based stains and paints.  The
percentages of Intersept ai in the end-use products is 20% and 100%. 
The products containing Intersept ai are formulated as a polymer bead or
a liquid concentrate.

The routes and durations of exposure evaluated in this assessment
include: short-term (ST) (1-30 days) and intermediate-term (IT) (1 - 6
months) dermal, inhalation, and incidental oral exposures.  The NOAEL
for all routes and durations of exposure is 62.5 mg/kg/day.  Since there
was no dermal absorption study available, it was assumed that the
chemical is absorbed by 100%.  The target MOE is 100 for all routes and
durations of exposure.  However, an additional uncertainty factor is
necessary to consider for the inhalation route since there was no
route-specific inhalation toxicity study; therefore an inhalation study
may be necessary for any inhalation scenario where the MOE is less than
1000.  It should be noted that since the toxicity endpoints for the all
the routes of exposure were the same, Total MOEs were necessary to
assess, where the Target MOE is 100.  It should be further noted that
since the vapor pressure of Intersept ai is low (i.e., <1 x10-6mmHg)
that inhalation exposure is only to the aerosol not the vapor.

	Based on examination of product labels describing uses for this
antimicrobial, it has been determined that handler exposure can occur
during occupational and residential painting as well as, in occupational
manufacturing facilities.  Post-application exposures are most likely to
occur in residential settings.  The representative scenarios selected by
AD were evaluated using maximum and minimum application rates as stated
on the product labels. To assess the handler and post-application
exposures and risks, AD used standard assumptions, surrogate unit
exposure data (from the CMA and Pesticide Handlers Exposure Database
(PHED)), 2005 Human and Environmental Risk Assessment on Ingredients of
Household Cleaning Products (HERA), and EPA’s Health Effects
Division’s (HED) Standard Operating Procedures (SOPs) for Residential
Exposure Assessments.

Handler Risk Summary

		For the residential handler exposure assessment, the ST dermal,
inhalation, and total MOEs for applicators of paint, containing the
minimum percent ai, using a brush/roller or airless sprayers result in
MOEs above 100, 1000, and 100 respectively.  Furthermore, all of the
carpet cleaner MOEs were above the appropriate target MOEs.   However,
the MOEs for the residential painters using paint containing the maximum
percent ai were below the target MOE of 100, as follows:

ST dermal exposures resulting from the application of paint using a
brush/roller:  MOE = 19.

ST dermal exposures resulting from the application of paint using an
airless sprayer:  MOE = 7.

ST inhalation exposures resulting from the application of paint using an
airless sprayer:  MOE = 700.  Note that although this MOE is above
100, it is below 1000 which indicates that an inhalation specific
toxicity study is warranted for this exposure scenario.

	For the occupational handler exposure assessment, only painting
scenarios were quantitatively assessed.  Based on information provided
by the registrants, it was assumed that all of the occupational
handling/loading in manufacturing facilities is done via closed loading
systems (i.e., closed totes and automated hoppers).  Therefore, these
occupational handler exposures are expected to be minimal.

		The ST dermal, inhalation, and total MOEs for occupational applicators
of paint, containing the minimum percent ai, using a brush/roller or
airless sprayers result in MOEs above 100, 1000, and 100 respectively. 
However, the MOEs for the occupational painters using paint containing
the maximum percent ai were below the target MOE of 100, as follows:

ST dermal exposures resulting from the application of paint using a
brush/roller:  MOE = 10.

ST dermal exposures resulting from the application of paint using an
airless sprayer:  MOE = 5.

ST inhalation exposures resulting from the application of paint using an
airless sprayer:  MOE = 210.  Note that although this MOE is above
100, it is below 1000 which indicates that an inhalation specific
toxicity study is warranted for this exposure scenario.

Post-application/Bystander Risk Summary

Occupational post-application exposures are assumed to be minimal and
therefore not quantitatively assessed.  For the residential
postapplication risk assessment, MOEs are above the target MOE of 100
for all scenarios except for the following:

ST/IT dermal exposure of children to treated mattress (cover or
ticking): 

MOE = 1 at maximum application rate and 100% transfer to skin

MOE = 6 at minimum application rate and 100% transfer to skin

MOE = 23 at maximum application rate and 5% transfer to skin

ST/IT dermal exposure of adults to treated mattress (cover or ticking): 

MOE = 2 at maximum application rate and 100% transfer to skin

MOE = 9 at minimum application rate and 100% transfer to skin

MOE = 38 at maximum application rate and 5% transfer to skin

ST incidental ingestion exposure of children to carpet cleaners: MOE =
44 at maximum application rate and 100% transfer to skin

IT incidental ingestion exposure of children to carpet cleaners: MOE =
92 at maximum application rate and 100% transfer to skin

ST dermal exposure of children to treated textiles: 

MOE = <1 at maximum application rate and 100% transfer to skin

MOE = 2 at minimum application rate and 100% transfer to skin

MOE = 17 at maximum application rate and 5% transfer to skin

MOE = 44 at minimum application rate and 5% transfer to skin

ST dermal exposure of adults to treated textiles: 

MOE = 1 at maximum application rate and 100% transfer to skin

MOE = 3 at minimum application rate and 100% transfer to skin

MOE = 26 at maximum application rate and 5% transfer to skin

MOE = 69 at minimum application rate and 5% transfer to skin

ST incidental ingestion exposure of children to treated textiles: MOE =
95 at maximum application rate 

Dietary and Drinking Water Risk Summary

	Based on the use patterns of Intersept ai, it is not expected that
there will be any dietary exposure.  Therefore, a dietary assessment was
not necessary to conduct.  Furthermore, since these uses occur in an
indoor environment, it is not expected that Intersept ai will impact any
source of drinking water.  Therefore, a drinking water assessment was
not necessary to conduct.

Aggregate Risk Summary

	ST and IT residential aggregate risk assessments were conducted for
children.  These assessments included both the dermal and oral routes of
exposure for the mattress, vinyl flooring and carpet cleaner scenarios. 
The resulting ST and IT MOEs of 86 and 91, respectively, are below the
target MOE of 100.

	A ST residential aggregate assessment was also conducted for adults. 
This assessment included dermal exposure to the mattress as well as,
dermal and inhalation exposures for handlers using treated carpet
shampoo.  The resulting MOE was above the target MOE of 100 and
therefore not a concern. 

Data Limitations and Uncertainties:

There are a number of uncertainties associated with this assessment,
including the following: 

Surrogate dermal and inhalation unit exposure values were from the
proprietary CMA (US EPA 1992) and Pesticide Handler Exposure Database
(US EPA 1998). These exposure data are of insufficient quality
therefore, AD requests that confirmatory monitoring data be generated to
support the values used in these assessments. 

Based on information provided by the registrants, it was assumed that
all of the occupational handling/loading activities in manufacturing
facilities are performed via closed loading systems (i.e., closed totes
and automated hoppers).  This closed loading language must be added to
the labels.  If the registrant determines that there is a potential for
open pouring then additional information on the amount of ai handled
must be provided, which will then be incorporated into this assessment.

The dermal absorption of 100% was assumed which resulted in conservative
dermal exposure estimates.  A dermal absorption study could be used to
refine the dermal exposures.

The quantities handled/treated were estimated based on information from
various sources, including HED’s Standard Operating Procedures (SOPs)
for Residential Exposure Assessments (US EPA 2000, 2001) and standard AD
assumptions that can be further refined from input from registrants. 

During the SMART Meeting (11/07/07) the registrant stated that the
targeted amount of ai applied to textiles (outer and underwear) is 0.75%
to 2% ai by weight of the fabric.  This specific application rate should
be specified on the label.

A confirmatory study is needed to verify the 5% transfer factor for
clothing and mattress covers.  The registrant indicated that they will
submit leaching/extraction data.  As soon as these data are submitted
and reviewed, the results will be incorporated into the assessment, as
appropriate.

1.0	 INTRODUCTION tc \l1 "1.0	INTRODUCTION 

		1.1	Purpose  tc \l2 "1.1	Purpose  

		This document presents the results of a review of the potential human
health effects of occupational and residential exposure to organic acid
esters of phosphoric acid (referred to as Intersept ai in the remainder
of this document).  This information is for use in EPA’s development
of the organic acid esters of phosphoric acid Reregistration Eligibility
Decision (RED) Document. 

		1.2	Criteria for Conducting Exposure Assessments tc \l2 "1.2	Criteria
for Conducting Exposure Assessments 

		An occupational and/or residential exposure assessment is required for
an active ingredient if (1) certain toxicological criteria are triggered
and (2) there is potential exposure to handlers (mixers, loaders,
applicators, etc.) during use or to persons entering treated sites after
application is complete.  For Intersept ai, both criteria are met.

In this document, scenarios were assessed by using unit exposure data to
estimate occupational and residential handlers’ exposures. Unit
exposures are estimates of the amount of exposure to an active
ingredient a handler receives while performing various handler tasks and
are expressed in terms of micrograms or milligrams (1mg = 1,000 µg) of
active ingredient per pounds of active ingredient handled.  A series of
unit exposures have been developed that are unique for each scenario
typically considered in assessments (i.e., there are different unit
exposures for different types of application equipment, job functions,
and levels of protection).  The unit exposure concept has been
established in the scientific literature and also through various
exposure monitoring guidelines published by the U.S. EPA and
international organizations such as Health Canada and OECD (Organization
for Economic Cooperation and Development).

Using surrogate unit exposure data, application rates from labels, and
estimates of daily amount handled, exposures and risks to handlers were
assessed.  The exposure/risks were calculated using the following
equations:

Daily Exposure: Daily dermal or inhalation handler exposures are
estimated for each applicable handler task with the application rate,
quantity treated/handled in a day, and the applicable dermal or
inhalation unit exposure using the following formula:

Daily Exposure:	E = UE x AR x AT						(Eq. 1)

Where:  

E	=	Amount (mg a.i./day) deposited on the surface of the skin that is
available for dermal absorption or amount inhaled that is available for
inhalation absorption;

UE	=	Unit exposure value (mg ai/lb ai) derived from August 1998 PHED
data or from 1992 CMA data;

AR	=	Maximum application rate based on a logical unit treatment, square
feet (sq. ft.), gallons (gal), or cubic feet (cu. ft). Maximum values
are generally used (lb a.i./sq ft, lb ai/gal, lb ai/cu ft); and

AT 	=	Normalized application area based on a logical unit treatment such
as square feet  (sq ft/day), gallons (gal/day), or cubic feet (cu
ft/day).

Daily Dose: The daily dermal or inhalation dose is calculated by
normalizing the daily exposure by body weight and adjusting, if
necessary, with an appropriate absorption factor.  For Intersept ai, an
oral endpoint was used for evaluation of dermal and inhalation
exposures; however, an absorption factor of 100% was used for all
exposures since chemical and route specific absorptions studies were not
available.  Daily dose was calculated using the following formula:

Daily Dose:	ADD = E x ABS							(Eq. 2)

			   BW						

Where:

ADD 	= 	Absorbed dose received from exposure to a chemical in a given
scenario (mg active ingredient/kg body weight/day);

E 	=	Amount (mg ai/day) deposited on the surface of the skin that is
available for dermal absorption or amount inhaled that is available for
inhalation absorption;

ABS 	= 	A measure of the amount of chemical that crosses a biological
boundary such as lungs (% of the total available absorbed); and

BW	= 	Body weight determined to represent the population of interest in
a risk assessment (kg).

Margins of Exposure:  Non-cancer inhalation and dermal risks for each
applicable handler scenario are calculated using a Margin of Exposure
(MOE), which is a ratio of the daily dose to the toxicological endpoint
of concern.

Margins of Exposure:	MOE = NOAEL or LOAEL					(Eq. 3)

					ADD

Where:

MOE 			= 	Margin of exposure, value used to represent risk or how close
a chemical exposure is to being a concern (unitless);

NOAEL or LOAEL	= 	Dose level in a toxicity study, where no observed
adverse effects (NOAEL) or where the lowest observed adverse effects
(LOAEL) occurred in the study; and

ADD 			= 	Average daily dose or the absorbed dose received from exposure
to a chemical in a given scenario (mg ai/kg body weight/day).

	In addition to the target MOEs from Table 3.2 that were used for the
analysis, a series of assumptions and exposure factors served as the
basis for completing the handler risk assessment.  Each general
assumption and factor for both residential and occupational assessments
is detailed below.  Assumptions specific to the use site category are
listed in each separate section of this document.  The general
assumptions and factors include:

Intersept ai products are registered for various use patterns and use
conditions too numerous to conduct a comprehensive assessment for this
document.  As such, this risk assessment has been patterned on a series
of scenarios that are believed to be representative of the primary of
Intersept ai uses.

Average body weights of 70 kg for adults and 15 kg for children were
used as appropriate to complete the non-cancer risk assessment.  

Exposure factors used to calculate daily exposures to handlers were
based on applicable data, if available.  When appropriate data were
lacking, values from a scenario deemed similar were used. 

The minimum and maximum application rates allowed by labels were used in
order to provide a range of exposure potentials.	

		1.3	Chemical Identification tc \l2 "1.3	Chemical Identification 

		The chemical under review is a group of three organic esters of
phosphoric acid (Intersept ai).  The Product Codes for this chemical is
111286, 129079 and 129090.  CAS RN are 1070-03-7, 68649-38-7 and
120579-32-0.  

		1.4	Physical/Chemical Properties tc \l2 "1.4	Physical/Chemical
Properties 

		Table 1.2 shows physical/chemical characteristics that have been
reported for organic esters of phosphoric acid.  The reader is referred
to the product chemistry and environmental fate chapters for a complete
overview of all of the physical/chemical properties.

Table 1.2.  Physical/Chemical Properties of Organic Esters of Phosphoric
acid



Molecular Weight	



Vapor Pressure	

5.3e-7 mmHg

6.1e-11 mmHg



2.0	 USE INFORMATION tc \l1 "2.0	USE INFORMATION 

		2.1	 Formulation Types and Percent Active Ingredient tc \l2 "2.1	
Formulation Types and Percent Active Ingredient 

		The products containing organic esters of phosphoric acid as the
active ingredient (a.i.) are formulated as a polymer bead and a soluble
concentrate.  Concentrations of Intersept ai in these products range
from 20% to 100%.

		

		2.2	Summary of Use Pattern and Formulations tc \l2 "2.2	Summary of Use
Pattern and Formulations 

	Intersept ai is an industrial fungistat and bacteriostat that is an
active ingredient in two registered products.  AD determined potential
occupational and residential exposure scenarios by reviewing these two
currently registered labels.  These scenarios are presented in Table
2.1.  Based on this review of the labels, it was determined that
Intersept ai products are intended for use as materials preservatives
(Use Site Category VII)  for use in various products such as coatings,
stains and paints, glues and adhesives, textiles, carpet backing, and
polymer products, vinyl products, mattress covers and ticking, floor
maintenance products (i.e., shampoos, cleaners, spot removers). 

Table 2.1. Potential Use Scenarios Based on Product Labels for Intersept
ai



Use Site Category	

Example Use Sites	

Scenarios



Use Site Category VII

Material Preservatives	

Used in the production of various household, institutional and
industrial items	

Addition to products during manufacture, including:

Carpet backing

Epoxy flooring, coating, tile and grout products

Vinyl products (wall coverings, car tops, awnings, tarpaulins, tents,
sails, drapes, shower curtains, flooring products, and films not for
food contact)

Plastic furniture (not for food service or storage)

Acrylic, urethane, wax and varnish floor sealers, finishes, and
maintainers (carpets shampoos, dry extraction compounds and cleaners,
spot removers)

Polyvinyl acetate indoor and outdoor paints

Polymeric laminates (not for food preparation surfaces)

Polymer concrete

Synthetic and non-woven textiles (wall coverings, car tops, awnings,
tarpaulins, tents, sails, drapes, shower curtains)

Polymeric packaging film (not for food contact)

Water, oil and solvent based paints, stains, and other coating systems
for use on interior and exterior surfaces, substrates, machinery and
equipment, including heating, ventilating and air conditioning systems

Molded polymeric and polymer concrete bath tubs, showers, bathroom
sinks, bathroom countertops and bathroom accessories

Natural and synthetic polymeric sealants, adhesives and caulking
compounds

Textile upholstery, mattresses, mattress ticking and mattress covers

Vinyl upholstery, mattresses, mattress ticking and covers

Topical treatment of textile products including apparel, outerwear and
undergarmets

Air filters for furnaces, air conditioners, air purification devices,
automobiles, and recirculating air handling systems

	

	From Table 2.1, representative exposure scenarios were selected for
assessment in this document.  These scenarios were selected to be
representative of the vast majority of uses and are believed to provide
high-end estimates of dermal, inhalation, or incidental ingestion
exposure.  The representative scenarios assessed in this document are
shown in Table 4.1 (residential) and Table 6.1 (occupational).

3.0	SUMMARY OF TOXICITY DATA tc \l1 "3.0	SUMMARY OF TOXICITY CONCERNS
RELATING TO EXPOSURE 

3.1	Acute Toxicity

 tc \l2 "3.1	Acute Toxicity 

Adequacy of database for Acute Toxicity:  The acute toxicity database
for organic esters of phosphoric acid is considered incomplete. The
acute toxicity data is summarized below in Table 3.1.

Table 3.1 Acute Toxicity Profile Organic Esters of Phosphoric Acid

Guideline Number	Study Type/Test substance (% a.i.)	MRID Number/
Classification	Toxicity Category

870.1100	Acute Oral Toxicity (gavage) – Rat 	42907901	IV

870.1200	Acute Dermal Toxicity – Rabbit 	42907902	IV

	Acute Inhalation Toxicity – Mouse 	40423801	III

870.2400	Primary eye irritation – Rabbit 	44858903	III

870.2500	Primary Skin irritation – Rabbit 	44858904	IV

870.2600	Dermal Sensitization – Guinea Pig	No study available

	

3.2	Summary of Toxicity Endpoints tc \l2 "3.2	Summary of Toxicity
Endpoints 

The toxicological endpoints were selected for organic esters of
phosphoric acid (Intersept ai).  Table 3.2 summarizes the toxicological
endpoints for Intersept ai used in the evaluation of exposures and MOEs.
 The reader is referred to the following memorandum for more detail:
Organic Esters of Phosphoric Acid: Toxicology Disciplinary Chapter for
the Issuance of the Reregistration Eligibility Decision (RED) Document;
Dated 11/26/07.

Table 3.2. Summary of Toxicological Doses and Endpoints for Organic
Esters of Phosphoric Acid

Exposure Scenario	Dose Used in 

Risk Assessment

(mg/kg/day)	Target MOE, UF, for Risk Assessment	Study and

 Toxicological Effects



Dietary Risk Assessments



Acute Dietary

(all populations)	This risk assessment is not currently required



Chronic Dietary

(all populations)	This risk assessment is not currently required



Non-Dietary Risk Assessments

Incidental Oral

Short-Term 

(1-30days) and Intermediate-Term

(1-6 months)  	NOAEL (males) = 62.5 	MOE = 100 (10x inter-species
extrapolation, 10x intra-species variation)	90-Day (Oral) Subchronic
Toxicity Study in Rats (MRID 41083601)

LOAEL (males) = 200 mg/kg/day based on decreased body weights and body
weight gain and food consumption.

Dermal

Short-Term 

(1-30days) and Intermediate-Term

(1-6 months)  	NOAEL (males) = 62.5	MOE = 100 (10x inter-species
extrapolation, 10x intra-species variation)	90-Day (Oral) Subchronic
Toxicity Study in Rats (MRID 41083601)

LOAEL (males) = 200 mg/kg/day based on decreased body weights and body
weight gain and food consumption.

Dermal

Long-Term

(> 6 months)	NOAEL (males) = 62.5	MOE = 300 (10x inter-species
extrapolation, 10x intra-species variation, 3x for use of a subchronic
endpoint for the long-term endpoint) 	90-Day (Oral) Subchronic Toxicity
Study in Rats (MRID 41083601)

LOAEL (males) = 200 mg/kg/day based on decreased body weights and body
weight gain and food consumption.

Inhalation

Short-Term 

(1-30days) and Intermediate-Term

(1-6 months)  	NOAEL (males) = 62.5	MOE = 1000 (10x inter-species
extrapolation, 10x intra-species variation, 10x route-to-route
extrapolation)	90-Day (Oral) Subchronic Toxicity Study in Rats (MRID
41083601)

LOAEL (males) = 200 mg/kg/day based on decreased body weights and body
weight gain and food consumption.

Cancer

(oral, dermal, inhalation)	No carcinogenicity data available for
Phosphoric Acid Esters.



4.0	RESIDENTIAL EXPOSURE ASSESSMENT tc \l1 "4.0	RESIDENTIAL EXPOSURE
ASSESSMENT  

4.1	Summary of Registered Uses tc \l2 "4.1	Summary of Registered Uses 

	Although no products containing Intersept ai are labeled for
residential uses, residents may be exposed to household items that have
been treated with Intersept ai through material preservation (e.g.,
paints, textiles, mattresses, floor cleaners, etc.).  Table 2.1 presents
a summary of exposure scenarios that may occur from the residential use
site category based on examination of product labels.  Table 4.1
identifies the representative exposure scenarios assessed in this
document.

Table 4.1. Representative Uses Associated with Residential Exposure 



Representative Use	

Exposure Scenario	

Application Method	

Registration #	

Application Rate

Using treated paints	ST handler: dermal and inhalation 	brush/ roller

airless sprayer	43670-1

	0.1% - 5% a.i. by weight

Using treated carpet cleaners	ST handler: dermal and inhalation

ST and IT post-app: child incidental ingestion and dermal	Low pressure
spray to simulate rug shampoo machine 

NA	43670-1

	0.0033 lb ai/gal and

6.5e-5 lb ai/gal

(5% ai x 8.34 lb/gal x 1 oz product/gal water x 1 gal/128 oz = 0.0033 lb
ai/gal)a

0.1% - 5% a.i. by weight

Treated vinyl floor	ST and IT post-app: child incidental ingestion and
dermal	NA	43670-1

	5% a.i. by weight

Using treated textiles (e.g., clothing and linen)	ST post-app: child
incidental ingestion and dermal	NA

	43670-1

	0.75% - 2% ai by weight b

Using treated mattresses	ST and IT post-app: child dermal	NA	43670-1

	1% - 2% ai by weight

a: Note that during the SMART meeting (11/7/07), the registrant
indicated that the treated carpet cleaner is diluted prior to use by the
consumer at a rate of 1 oz product/ 1 gallon of water 

b: Note that during the SMART meeting (11/7/07), the registrant
indicated that the topical textile treatment rate is 0.75% - 2%ai by
weight of fabric.  This specific textile use rate needs to be indicated
on the label. 

	

	4.2	Dietary Exposure tc \l2 "4.2	Dietary Exposure/Risk Pathway  

	Based on the use patterns of Intersept ai, it is not expected that
there will be any dietary exposure.  Therefore, a dietary assessment was
not necessary to conduct.  

	4.3	Drinking Water Exposure tc \l2 "4.3	Drinking Water Exposure/Risk
Pathway  

Based on the use patterns of Intersept ai, since these uses occur in an
indoor environment, it is not expected that Intersept ai will impact any
source of drinking water.  Therefore, a drinking water assessment was
not necessary to conduct. 

	4.4	Residential Exposures tc \l2 "4.4	Residential Exposures 

	4.4.1	Residential Handler Exposures tc \l3 "4.4.1	Residential Handler
Exposures 

	The types of products treated with Intersept ai that are handled in a
residential setting are treated paints, textiles, mattresses, vinyl
products,  floor cleaners, and similar products as described in Table
4.1.  The short-term inhalation and dermal residential painter and
carpet cleaner exposures were assessed and are considered to be
representative of all other residential handler exposures.  Only
short-term exposure durations (1 to 30 days) were estimated because it
was assumed that a homeowner or do-it-yourself painter and carpet
cleaners would typically occur on an intermittent basis.

Exposure Calculation Assumptions

Unit Exposure Values:  There are no chemical-specific exposure data to
assess residential handler exposures however surrogate data are
available for painting with a brush and an airless sprayer and applying
carpet cleaners using a low pressure handwand.  The surrogate data are
based on PHED data for painters and CMA data for carpet cleaners wearing
no gloves or respiratory protection.

For the brush/roller scenario, the PHED dermal and inhalation unit
exposure values for a residential handler applying a pesticide using a
paint brush were used.  The test subjects were painting a bathroom with
a paint brush.  The dermal unit exposure value (230 mg/lb a.i.)
represents a handler wearing short pants, short sleeves and no gloves. 
The inhalation unit exposure value (0.28 mg/lb a.i.) represents a
handler wearing no respiratory protection. 

For the airless sprayer scenario, the PHED unit exposure values for a
residential handler applying a pesticide using an airless sprayer were
used.  The test subjects were staining the outside of a house with an
airless sprayer.  Although these exposures may differ slightly from
exposures of painters of Intersept ai persevered products, these data
are judged to be adequately representative.  The dermal unit exposure
value (79 mg/lb a.i.) represents a handler wearing short pants, short
sleeves and no gloves.  The inhalation unit exposure value (0.83 mg/lb
a.i.) represents a handler wearing no respiratory protection. 

For low pressure hand wand, the CMA unit exposure value for a low
pressure spray was used for the residential carpet cleaner.   The dermal
unit exposure value (191 mg/lb a.i.) represents a handler wearing no
gloves.  The inhalation unit exposure value (0.681 mg/lb ai) represents
a handler wearing no respiratory protection.  The values were based on
data collected from eight replicates who hand sprayed carpet using 200
psi, and then used a push broom rake to raise the carpet nap.

Quantity handled/treated: The quantities handled/treated were estimated
based on information from various sources and assumptions. 

For the brush/roller in paint applications, it is assumed that 20 lbs
(approximately 2 gallons) of treated paint will be used.  This is based
on the 90th percentile value of 8 gallons of latex paint used per year
divided by the mean frequency of 4 painting events/year.

 For the airless sprayer in paint applications, it is assumed that 150
lbs           (approximately 15 gallons) of treated paint will be used. 
This is based on the coverage of 200 ft2/gallon and a house size of 40 x
30 x 20 ft (surface area of 2,800 ft2).

For low pressure hand wand for carpet shampoo applications, it was
assumed that 2 gallons are used in all indoor applications.

Duration of Exposure: The duration of exposure for most handler
homeowner uses is believed to be best represented by the short-term
duration (1 to 30 days).  The reason that short-term duration was chosen
to be assessed is because painting and carpet shampooing is episodic in
nature, not daily.  In addition, homeowners are assumed to use different
products with varying activities, not exclusively Intersept ai treated
products (e.g., in-can paint preservative).

Results

	Table 4.2 presents the calculations of the dermal and inhalation doses
and MOEs for a residential painter working with treated paint and
residential carpet cleaners.  The short-term dermal and inhalation MOEs
estimated for painters at the lower application rate and carpet cleaners
at the maximum rate are above the target MOEs of 100 and 1000 and not a
concern.  However, the short-term dermal and inhalation MOEs estimated
for painters at the maximum application rate are below the target MOE of
100 and 100 and therefore a concern.

Table 4.2 Intersept ai Short-Term Residential Handler Exposures and MOEs

Exposure Scenario	Application Method	Application Ratea	Quantity Handled
per dayb	Dermal Unit Exposure

(mg/lb a.i.)	

Inhalation Unit Exposure

(mg/lb a.i.)	Dermal Daily Dose (mg/kg/day) c	Inhalation Daily Dose
(mg/kg/day) c	Dermal MOE d

(Target MOE = 100)	Inhalation MOE d

(Target MOE = 100)	Total MOE

Carpet cleaners	Low Pressure Spray	6.5E-5 lb ai/gal	2 gal	191	0.681
1.8E-04	6.3E-07	350,000	99,000,000	350,000



0.0033lb ai/gal	2 gal	191	0.681	8.9E-03	3.2E-05	7,000	2,000,000	7,000

Painting	Paint brush	0.1% ai by wt	20 lbs	230	0.28	0.066	8.0E-05	950
780,000	950



5% ai by wt	20 lbs	230	0.28	3.3	0.0040	19	16,000	19

	Airless sprayer	0.1% ai by wt	150 lbs	79	0.83	0.17	0.0018	370	35,000
370



5% ai by wt	150 lbs	79	0.83	8.46	0.089	7	700	7

a	Application rates are based on the minimum and maximum application
rates determined from EPA registered labels (see Table 4.1).

b	Amount handled per day values are standard EPA assumptions	

c	Daily dose (mg/kg/day) = [unit exposure (mg/lb a.i.) x application
rate (% a.i. weight or lb ai/gal) x quantity handled (lb/day or gal/day)
x absorption factor (1.0 for dermal and  inhalation)]/ Body weight (70
kg).

d	MOE = NOAEL / Daily Dose.  [Where short-term dermal and inhalation
NOAEL = 62.5 mg/kg/day]. Target MOE = 100.  Note: if inhalation MOE is
below 1000 then an inhalation specific toxicity study may be warranted

e	Total MOE = 1/((1/MOEdermal) + (1/MOEinhal))

	4.4.2	Residential Post-application Exposures tc \l3 "4.4.2	Residential
Post-application Exposures 

	For the purposes of this screening level assessment, postapplication
scenarios have been developed that encompass high end exposure scenarios
that are representative of all uses. As shown in Table 4.1,
representative postapplication scenarios assessed include contacting
carpets cleaned with treated shampoo (dermal and incidental oral
exposure of children), contacting treated vinyl floors (dermal and
incidental oral exposure of children), wearing treated clothing (dermal
exposure of children and adults), mouthing treated textiles such as
clothing and blankets (incidental oral exposure to children), and
contacting treated mattresses/covers (dermal exposure to children and
adults).   It should be noted that because Intersept ai has a relatively
low vapor pressure, post application inhalation exposures were not
assessed.

	4.4.2.1 Carpet Shampoo

	Flooring maintenance products such as carpet shampoos can be
treated/preserved with Intersept ai during the manufacturing process. 
Therefore post application dermal and incidental oral exposures to
treated carpet may occur.  Since the carpet in facilities such as
daycares can be cleaned on a regular basis there is potential for
exposure to occur everyday, assuming that Intersept ai has a relatively
long half life in indoor environments.  Therefore both short- and
intermediate-term exposures durations were assessed. 

	It should be noted that one of the primary uses of Intersept ai is for
preservation of carpet backing.  Exposure to carpet backing is
considered to be negligible and therefore was not quantitatively
assessed. tc \l4 "4.4.2.1	Treated Carpet 

Child Dermal Exposure from Treated Carpet Shampoo

Exposure Calculations

	Short- and Intermediate exposures - There is the potential for short
and intermediate-term dermal exposures leading to systemic effects when
children come into contact with carpeting cleaned with treated shampoo. 
Exposures and MOEs were calculated for children contacting treated
carpet in residential homes.  To determine child short- and
intermediate-term exposures to Intersept ai remaining in carpeting, the
following equations were used:

Potential doses are calculated as follows: 

PDD = C x SA x TR 

	        BW						

where: 

PDD	= 	potential daily dose (mg/kg/day);

C 	= 	concentration on carpet (mg/m2);

SA 	= 	surface area of skin that contacts the treated carpet (m2/day);

TR 	= 	transferable residue from carpet to skin (%); and

BW 	= 	body weight (kg).

and

C = T x App x FR x CF1 x CF2 x CF3

where:

C 	= 	concentration on carpet (mg/m2);

	T	=	treatment solution (lb ai/gal) (see Table 4.1)

	App	=	application rate (gal/ ft2)

FR	=	fraction remaining on floor (25%);

	CF1	=	10.76 ft2/m2

	CF2	=	454 g/lb

	CF3	=	1000 mg/g

Assumptions

The product is diluted at a rate of 1 ounce of product per gallon of
water; the percent of Intersept ai in the formulation is 0.1% to 5%
(e.g., EPA Reg. No. 43670-1).  This is equivalent to a treatment
solution of 6.5e-5 to 0.0033 lb ai/gallon water (i.e., 5% ai x 8.34
lb/gal x 1 oz product/gal water x 1 gal/128 oz = 0.0033 lb ai/gal)

The carpet shampoo is applied at a rate of 1 gallon of solution to 300
ft2 carpet (standard AD assumption).

No data could be found regarding the quantity of solution residue left
on the carpet after treatment.  As a conservative measure, it has been
assumed that 25% of the cleaning solution remains after the final
cleaning (standard AD assumption).

Toddlers (3 years old) were used to represent the 1 to 6 year old age
group.  A body surface area of 0.657 m2 and a body weight of 15 kg were
assumed, which are the median values for 3 year olds (USEPA, 1997).

No transferable residue data were available that could be used to
estimate the transfer of Intersept ai from the carpet to skin. 
Therefore, it is assumed that 100% and 5% of the residue on the treated
carpet is available for dermal transfer (USEPA, 2000 and 2001). 
Confirmatory transfer data is required to support the 5% transfer rate. 
It should be noted that the registrant indicated that they will submit
leaching/extraction data.  As soon as these data are submitted and
reviewed, the results will be incorporated into the assessment, as
appropriate.

Results

	Table 4.3 shows the calculations of the short- and intermediate-term
dermal doses and MOEs for children contacting carpet cleaned with
treated shampoo.  All of the MOEs are above the target MOE and therefore
not a concern.  

Table 4.3: ST and IT Dermal Post-Application Exposures and MOEs for
Toddlers Contacting Carpets Cleaned with Treated Shampoo

Treatment solution 

(lb ai/gallon)	Treatment coverage

(gal/ft2)	Fraction remaining after cleaning

(%)	 Carpet conc.a 

(mg ai/m2)	

Transferable residue from carpet to skin (%)	

Surface area of skin in contact with carpet (m2/day)	

Dermal daily doseb (mg/kg/ day)	

Dermal MOEc (Target MOE=100)

6.5e-5	300	25%	0.27	100%	0.657	0.012	5400

6.5e-5	300	25%	0.27	5%	0.657	0.00058	110,000

0.0033	300	25%	13.3	100%	0.657	0.58	110

0.0033	300	25%	13.3	5%	0.657	0.029	2,100



a.	Carpet conc. (mg/m2) = (trt.  sol. lb ai/gal) x (1 gal/300 ft2
carpet) x  (10.8 ft2/m2) x (454 gram/lb) x (1000 mg/gram)

b .	Dermal Daily Dose (mg/kg/day) = carpet conc (mg/m2) x surface area
of skin in contact with carpet (m2/day) x transferable residue from
carpet to skin (%) x dermal absorption (100%) / body weight (kg)

c.    Dermal MOE = NOAEL (62.5 mg/kg/day) / Dermal Daily Dose
(mg/kg/day) 

Child Incidental Ingestion Exposure from Treated Carpet Shampoo

	

Exposure Calculations

	

	Short- and intermediate-term exposures – There is potential for
short- and intermediate-term incidental oral exposures when children
exhibiting hand-to-mouth behavior come into contact with carpeting
cleaned with Intersept ai treated shampoo.  Incidental oral exposures
and MOEs were calculated for children contacting treated carpet in
residential or commercial day care settings.  To determine child short-
and intermediate-term incidental oral exposure to Intersept ai on
carpeting, the following equations were used:

PDD = C x SA x FQ x TR x SE x ET 

	              BW						

where: 

PDD	= 	potential daily dose (mg/kg/day);

C 	= 	concentration on carpet (mg/m2);

	SA	=	Surface area of the hands that contact both the treated area, and
the individuals mouth (cm2/event);

	FQ	=	Frequency of hand-to-mouth events (events/hr);

	TR 	= 	transferable residue from carpet to skin (%);  

	SE	=	Saliva extraction efficiency (unitless fraction); 

	ET	=	Exposure time (hrs/day);

BW 	= 	body weight (kg).

and

C = T x App x FR x CF1 x CF2 x CF3

where:

C 	= 	concentration on carpet (mg/m2);

	T	=	treatment solution (lb ai/gal) (see Table 4.1)

	App	=	application rate (gal/ ft2)

FR	=	fraction remaining on floor (25%);

	CF1	=	10.76 ft2/m2

	CF2	=	454 g/lb

	CF3	=	1000 mg/g

Assumptions

The product is diluted at a rate of 1 ounce of product per gallon of
water; the percent of Intersept ai in the formulation is 0.1% to 5%
(e.g., EPA Reg. No. 43670-1).  This is equivalent to a treatment
solution of 6.5e-5 to 0.0033 lb ai/gallon water (i.e., 5% ai x 8.34
lb/gal x 1 oz product/gal water x 1 gal/128 oz = 0.0033 lb ai/gal)

The carpet shampoo is applied at a rate of 1 gallon of solution to 300
ft2 carpet (standard AD assumption).

No data could be found regarding the quantity of solution residue left
on the carpet after treatment.  As a conservative measure, it has been
assumed that 25% of the cleaning solution remains after the final
cleaning (standard AD assumption).

The surface area of the hands that contact both the treated area and the
individual’s mouth per exposure event is 20 cm2/event (US EPA 2001).

The frequency of hand-to-mouth events is assumed to be 20 events/hr for
ST exposures and 9.5 events/hr for IT exposures (US EPA 2001).

No transferable residue data were available that could be used to
estimate the transfer of Intersept ai from the carpet to skin. 
Therefore, it is assumed that 100% and 5% of the residue on the treated
carpet is available for dermal transfer (USEPA, 2000 and 2001). 
Confirmatory transfer data is required to support the 5% transfer rate. 
It should be noted that the registrant indicated that they will submit
leaching/extraction data.  As soon as these data are submitted and
reviewed, the results will be incorporated into the assessment, as
appropriate.

The saliva extraction efficiency is assumed to be 50% (US EPA 2001).

The time of exposure is assumed to be 8 hrs/day (US EPA 2001).

The body weight of a child was assumed to be 15 kg.

Results

	Table 4.4 shows the calculations of the short- and intermediate-term
incidental oral exposures and MOEs for children contacting carpet
cleaned with treated shampoo.  All of the MOEs expect for one is above
the target MOE.  The short-term oral MOE at the highest application rate
and 100% residue transfer to skin is below the target MOE of 100.

Table 4.4: ST and IT Oral Post-Application Exposures and MOEs for
Toddlers Contacting Carpets Cleaned with Treated Shampoo



Treatment solution

(lb ai/gallon)	Treatment coverage

(gal/ft2)	Fraction remaining after cleaning

(%)	Carpet conc.a

(mg ai/cm2)	

Transferable residue from carpet to skin (%)	

Surface area of hand in contact with carpet and mouth (cm2/event)
Frequency of hand to mouth

(event/hr)	Exposure Time

(hr/day)	Saliva Extraction

(%)	

Oral daily doseb

(mg/kg/ day)	

Oral MOEc (Target MOE=100)

Short -Term

6.5e-5	300	25%	0.00027	100%	20	20	8	50	0.028	2,200

6.5e-5	300	25%	0.00027	5%	20	20	8	50	0.0014	44,000

0.0033	300	25%	0.013	100%	20	20	8	50	1.4	44

0.0033	300	25%	0.013	5%	20	20	8	50	0.071	880

Intermediate-Term

6.5e-5	300	25%	0.00027	100%	20	9.5	8	50	0.013	4,600

6.5e-5	300	25%	0.00027	5%	20	9.5	8	50	0.00067	93,000

0.0033	300	25%	0.013	100%	20	9.5	8	50	0.67	93

0.0033	300	25%	0.013	5%	20	9.5	8	50	0.034	1,900



a.	Carpet conc. (mg/cm2) = (trt.  sol. lb ai/gal) x (1 gal/300 ft2
carpet) x  (10.8 ft2/m2) x (454 gram/lb) x (1000 mg/gram) x (1000
cm2/m2)

b .	Oral Daily Dose (mg/kg/day) = carpet conc (mg/m2) x transferable
residue from carpet to skin (%) x surface area hands (cm2/day) x
frequency (event/hr) x exposure time (hr/day) x saliva extraction (%)/
body weight (kg)

c.   Oral MOE = NOAEL (62.5 mg/kg/day) / Oral Daily Dose (mg/kg/day) 

	Because the dermal and incidental oral toxicity endpoints are based on
the same study, Total MOEs were necessary to assess.  The Total MOEs for
exposure to carpet cleaners are presented in Table 4.5.  All Total MOEs
except for those evaluated at the maximum application rate and 100%
residue transfer are above the Target MOE of 100.  A confirmatory
residue transfer study is needed to support the 5% transfer assumption.

Table 4.5: ST and IT Total MOEs for Toddlers Contacting Carpets Cleaned
with Treated Shampoo

	ST MOEs	IT MOEs

	Min rate, 100% transfer	Min rate, 5% transfer	Max rate, 100% transfer
Max rate, 5% transfer	Min rate, 100% transfer	Min rate, 5% transfer	Max
rate, 100% transfer	Max rate, 5% transfer

Dermal	5,400	110,00	110	2,100	5,400	110,00	110	2,100

Oral	2,200	44,000	44	880	4,600	93,000	93	1,900

Total	1,600	31,00	31	620	2,500	50,000	50	990

Total MOE = 1/ (1/MOEdermal) + (1/ MOE oral))

4.4.2.2	Treated Vinyl tc \l4 "4.4.2.1	Treated Vinyl 

	Vinyl tiles used for flooring can be treated with Intersept ai during
the manufacturing process.  Therefore post application dermal and
incidental oral exposures to treated vinyl flooring may occur.  Since
the vinyl is actually impregnated with Intersept ai and the vinyl can be
used in a residential setting there is potential for exposure to occur
everyday, assuming that Intersept ai has a relatively long half life in
indoor environments.  Therefore both short- and intermediate-term
exposures durations were assessed.

Child Dermal Exposure from Treated Vinyl

Exposure Calculations

	

	Short- and Intermediate-term exposures - There is the potential for
short- and intermediate-term vinyl exposures leading to systemic effects
when children come into contact with vinyl treated with Intersept ai. 
Exposures and MOEs were calculated for children contacting treated vinyl
in residential homes.  To determine child intermediate-term exposure to
Intersept ai in vinyl, the following equation was used:

PDD = D x VT x CF1 x SA x WF1 x WF2 x WF3 x CF2 

				BW

where:

PDD 	= 	Potential daily dose (mg/kg/day)

D 	= 	Vinyl weight density (1.3 g/cm3)

VT	=	Vinyl thickness (3 mm)

CF1 	= 	Conversion factor (0.001 cm/mm)

SA 	= 	Body surface area contacting vinyl (cm2/day)

WF1 	= 	Weight fraction of Intersept ai in commercial product (%)

WF2 	= 	Weight fraction of Intersept ai available at the surface of
impregnated vinyl (unitless)

WF3 	= 	Weight fraction Intersept ai transferred from vinyl to skin
(unitless)

CF2 	= 	Conversion factor (1000 mg/g)

DA	=	Dermal absorption (%)

BW 	= 	Body weight (kg)

Assumptions

The maximum fraction of Intersept ai in the vinyl flooring is 5% (EPA
Reg. No. 43670-1).

The vinyl density is 1.3 g/cm2 based on the density of polyvinyl
chloride, and vinyl flooring is assumed to be 3 mm thick. 

Because Intersept ai is impregnated in the vinyl matrix, it was assumed
that not all of the additive was available for exposure. It was assumed
that 0.5% of the Intersept ai impregnated within the vinyl matrix is
available at the surface of the flooring which is subsequently available
for human exposure (standard AD assumption)

It was assumed that 10% of the Intersept ai on the vinyl surface is
transferred to skin (US EPA 2001).

It was assumed that the skin area contacting the vinyl was 6570 cm2
(median SA of a toddler, US EPA 1997b).

Due to the lack of a chemical specific dermal absorption study, 100% was
used for DA.

The body weight of a child was assumed to be 15 kg.

Results

	Table 4.6 shows the calculations of the short- and intermediate-term
dermal doses and MOEs for children contacting treated vinyl.  The short-
and intermediate-term MOEs are above the target MOE of 100 and therefore
not a concern.  

Table 4.6.  Short- and Intermediate-term Dermal Exposures and MOEs for
Children Contacting Treated Vinyl Flooring

% a.i.	Vinyl density (g/cm3)	Vinyl flooring thickness 

(mm)	Fraction available on surface of vinyl 	Fraction transferred to
skin	Skin surface area contacting vinyl 

(cm2)	Dermal Exposure a 

(mg/kg/day)	ST/IT Dermal MOE 

(Target MOE= 100) b

5%	1.3	3	0.5%	10%	6570	0.043	1,500

a 	Equations used to estimate exposure are presented above.

b	MOE = NOAEL/exposure [Where ST and IT NOAEL= 62.5 mg/kg/day]. 

Child Incidental Ingestion Exposure from Treated Vinyl

	

Exposure Calculations

	

	Short- and intermediate-term exposures – There is potential for
short- and intermediate-term incidental oral exposures when children
exhibiting hand-to-mouth behavior come into contact with vinyl flooring
treated with Intersept ai.  Incidental oral exposures and MOEs were
calculated for children contacting treated vinyl in residential or
commercial day care settings.  To determine child short- and
intermediate-term incidental oral exposure to Intersept ai on vinyl
flooring, the following equation was used:

PDD = D x VT x CF1 x SA x WF1 x WF2 x WF3 x WF4 x SE x ET x CF2

				BW

where:

PDD 	= 	Potential daily dose (mg/kg/day)

D 	= 	Vinyl weight density (1.3 g/cm3)

VT	=	Vinyl thickness (3 mm)

CF1 	= 	Conversion factor (0.001 cm/mm)

SA 	= 	Surface area of the hands that contact both the treated area, and
the individual’s mouth (cm2/event)

WF1 	= 	Weight fraction of Intersept ai in vinyl (%)

WF2 	= 	Weight fraction of Intersept ai transferred from vinyl to skin
(%)

WF3 	= 	Weight fraction of Intersept ai available on surface of
impregnated vinyl (%)

WF4 	= 	Weight fraction of Intersept ai transferred from vinyl to skin
(%)

SE 	= 	Saliva extraction efficiency (%)

FQ 	= 	Frequency of hand-to-mouth events (events/hr)

ET 	=  	Exposure time (hr/day)

CF2 	= 	Conversion factor (1000 mg/g)

BW 	= 	Body weight (kg)

Assumptions

The maximum fraction of Intersept ai in the vinyl flooring is 5% (EPA
Reg. No. 43670-1).

The vinyl density is 1.3 g/cm2 based on the density of polyvinyl
chloride, and vinyl flooring is assumed to be 3 mm thick. 

The surface area of the hands that contact both the treated area and the
individual’s mouth per exposure event is 20 cm2/event (US EPA 2001).

Because Intersept ai is impregnated in the vinyl matrix, it was assumed
that not all of the additive was available for exposure. It was assumed
that 0.5% of the Intersept ai impregnated within the vinyl matrix is
available at the surface of the flooring which is subsequently available
for human exposure (standard AD assumption)

It was assumed that 10% of the Intersept ai on the vinyl surface is
transferred to skin contacting the flooring (US EPA 2001).

The saliva extraction efficiency was assumed to be 50% (US EPA 2000).

The frequency of hand-to-mouth events was assumed to be 20 events/hr for
ST exposures and 9.5 events/hr for IT exposures (US EPA 2001).

The time of exposure was assumed to be 4 hrs/day (US EPA 2001).

The body weight of a child was assumed to be 15 kg.

Results

	Table 4.7 shows the calculations of the short- and intermediate-term
incidental oral exposures and MOEs for children contacting treated
vinyl.  Both short- and intermediate-term 

MOEs are above the target MOE of 100 and 300, respectively, and
therefore not a concern.  

Table 4.7.  Short- and Intermediate-term Incidental Oral Exposures and
MOEs for Children Contacting Treated Vinyl Flooring

Duration	% a.i.	Vinyl density (g/cm3)	Vinyl flooring thickness (mm)
Fraction available on surface of vinyl 	Fraction transferred to skin
Saliva extraction efficiency	Surface area of hands (cm2)	Frequency of
hand-to-mouth events (events/hr)	Exposure time (hrs/day)	Exposure a 

(mg/kg/day)	ST/IT MOE (Target MOE = 100) b

ST	5%	1.3	3	0.5%	10%	50%	20	20	4	0.0052	12,000

IT	5%	1.3	3	0.5%	10%	50%	20	9.5	4	0.0025	25,000

a 	Equations used to estimate exposure are presented above.

b	MOE = NOAEL/exposure estimate [Where: ST and IT Oral NOAEL = 62.5
mg/kg/day]. 

	Because the dermal and incidental oral toxicity endpoints are based on
the same study, Total MOEs were necessary to assess.  The Total MOEs for
exposure to treated vinyl are presented in Table 4.8.  All Total MOEs
are above the Target MOE of 100 and therefore not a concern.

Table 4.8: ST and IT Total MOEs for Toddlers Contacting Treated Vinyl

	ST MOEs	IT MOEs

	Max rate, 10% transfer	Max rate, 10% transfer

Dermal	1,500	1,500

Oral	12,000	25,000

Total	1,300	14,000

Total MOE = 1/ (1/MOEdermal) + (1/ MOE oral))

	4.4.2.3	Textiles (Clothing)  tc \l4 "4.4.2.3	Textiles (Clothing) 

	Textiles (which include fabric used for clothes – outerwear and
underwear) can be treated with Intersept ai after the manufacturing
process via a topical treatment.  Therefore post application dermal and
incidental oral exposures to treated clothing may occur.  It was assumed
that not all clothing is treated with Intersept ai and the clothing that
is treated will not be worn everyday therefore exposure would occur
intermittently.  Thus only short-term exposures durations were assessed.

	

Dermal Exposure to Treated Clothing

Exposure Calculations	

	There is the potential for short-term dermal exposure when adults or
children contact clothing made of textiles that have been
commercially/industrially treated with Intersept ai.  To determine the
short-term dermal exposure to Intersept ai for this scenario, the
following equation was used:

PE = D x WF1 x WF2 x SA x DA 

                           BW

where:

PE 	= 	Potential exposure (mg/cm2)

P 	= 	Textile density (mg/cm2)

WF1 	= 	Weight fraction of commercial product in textile (%)

WF2 	= 	Weight fraction of Intersept ai transferred from textile to skin
(%)

SA	=	Body surface area contacting treated clothing (cm2/day)

DA	=	Dermal absorption (%)

BW	=	Body weight (kg)

Assumptions

The textile density is 10 mg/cm2 based on the density of mixed cotton
and synthetics (HERA 2003). 

During the SMART Meeting (11/07/07) the registrant stated that the
targeted amount of ai applied to textiles (outer and underwear) is 0.75%
to 2% ai by weight of the fabric.  This specific application rate should
be specified on the label.

Toddlers (3 years old) were used to represent the 1 to 6 year old age
group.  A body surface area of 5670 cm2 (total body minus the head) and
a body weight of 15 kg were assumed, which are the median values for 3
year olds (USEPA, 1997).

An adult body surface area of 17,000 cm2 (total body minus the head) and
a body weight of 70 kg were assumed (USEPA, 1997).

Since there are no clothing specific residue transfer factors available
at this time a default of 100% and 5% were used.  The 5% residue
transfer factor is based on the default residue transfer from treated
carpets and a confirmatory study is needed to support this assumption
(US EPA 2001).  It should be noted that the registrant indicated that
they will submit leaching/extraction data.  As soon as these data are
submitted and reviewed, the results will be incorporated into the
assessment, as appropriate.

Due to the lack of a chemical specific dermal absorption study, 100% was
used for DA.

Results

	Table 4.9 shows the calculation of the short-term dermal exposures and
MOEs for children and adults contacting treated textile/clothing.  All
MOEs are below the Target MOE of 100 and are therefore considered a
concern.

	Table 4.9.  Short-term Dermal Exposure and MOE for Adults and Children
Contacting Treated Clothing

Duration	% a.i.	Cloth density (mg/cm2)	Fraction transferred to skin	Body
Surface Area Contacting Cloth

(cm2/day)	Exposure a 

(mg/kg/day)	ST MOE 

(Target MOE = 100) b

Child

ST	2%	10	100%	5670	75.6	<1

ST	2%	10	5%	5670	3.8	17

ST	0.75%	10	100%	5670	28.4	2

ST	0.75%	10	5%	5670	1.4	44

Adult

ST	2%	10	100%	17,000	48.6	1

ST	2%	10	5%	17,000	2.4	26

ST	0.75%	10	100%	17,000	18.2	3

ST	0.75%	10	5%	17,000	0.9	69

a 	The equation used to estimate exposure is presented above.

b	MOE = NOAEL/exposure  [Where: ST dermal NOAEL = 62.5 mg/kg/day]. 

Child Incidental Ingestion Exposure from Wearing Treated Clothing

	

Exposure Calculations

	

	There is the potential for short-term incidental ingestion exposures
when children come into contact with textiles treated with Intersept ai.
 For reasons specified previously, only short-term exposures were
assessed.  The exposure and MOE were calculated for children contacting
treated textiles.  To determine child short-term oral exposure to
Intersept ai in textiles, the following equation was used:

 

where:

PDD 	= 	Potential daily dose (mg/kg/day)

P 	= 	Textile weight density (mg/cm2)

WF1  	= 	Weight fraction of Intersept ai in commercial product (% ai)

SA	=	Surface area of fabric that is mouthed (cm2/day)

SE 	= 	Saliva extraction efficiency (%)

BW 	= 	Body weight (kg)

Assumptions

During the SMART Meeting (11/07/07) the registrant stated that the
targeted amount of ai applied to textiles (outer and underwear) is 0.75%
to 2% ai by weight of the fabric.  This specific application rate should
be specified on the label.

The textile density is 10 g/cm2 based on the density of mixed cotton and
synthetics (HERA 2003). 

The area of fabric that is mouthed per day is assumed to be 100 cm2 (AD
standard assumption)

The saliva extraction efficiency is assumed to be 50% (US EPA 2001).

The body weight of a child was assumed to be 15 kg.

Results

	Table 4.10 shows the calculations of the short-term incidental oral
exposures and MOEs for children mouthing treated textiles.  The
resulting MOE at the minimum application is above the target MOE of 100
and therefore not a concern. 

Table 4.10.  Short-term Incidental Oral Exposures and MOEs for Children
Contacting Treated Clothing

Duration	% a.i.	Cloth density (mg/cm2)	Area of fabric mouthed (cm2)
Saliva extraction efficiency	Exposure a 

(mg/kg/day)	ST MOE 

(Target MOE = 100) b

ST	2%	10	100	50%	0.67	94

ST	0.75%	10	100	50%	0.25	250

a 	The equation used to estimate exposure is presented above.

b	MOE = NOAEL/exposure [Where: ST oral NOAEL = 62.5 mg/kg/day]. 

	Because the dermal and incidental oral toxicity endpoints are based on
the same study, Total MOEs were necessary to assess.  Since all of the
dermal MOEs were below the Target MOE the resulting Total MOEs will also
be below the Target MOE and are therefore a concern.

	4.4.2.4	Mattresses tc \l4 "4.4.2.2	Mattresses 

	Textile and vinyl upholstery such as mattresses, mattress ticking and
mattress covers can be treated with Intersept ai during the
manufacturing process.  Therefore post application dermal exposures to
treated mattresses may occur.  It was assumed that exposure to a textile
mattress cover will represent exposure to all other mattress components.
 Since the mattress cover is actually impregnated with Intersept ai and
it can be used everyday, both short- and intermediate-term exposures
durations were assessed.

Dermal Exposure to Treated Mattress Covers

Exposure Calculations	

	Short- and Intermediate-term exposures - There the potential for short-
and intermediate-term exposures leading to systemic effects when adults
and children come into contact with mattress covers treated with
Intersept ai, through the regular use of the mattress.  Exposures and
MOEs were calculated for children and adults contacting treated
mattresses in residential homes.  To determine short and
intermediate-term exposures to Intersept ai in mattresses, the following
equation was used:

PDD = D x WF1 x WF2 x PF x SA x DA

                                 BW

where:

PDD 	= 	Potential daily dose (mg/kg/day)

D	= 	Mattress textile weight density (mg/cm2)

WF1 	= 	Weight fraction of Intersept ai in the mattress cover (%)

WF2 	= 	Weight fraction of Intersept ai transferred from the mattress
cover to skin (cover)

PF	=	Protection factor from single layer of clothing/sheet (%)

SA 	= 	Body surface area contacting mattress (cm2/day)

DA	=	Dermal absorption (%)

BW 	= 	Body weight (kg)

Assumptions

The fraction of Intersept ai in the mattress cover is 1% to 5% (EPA Reg.
No. 43670-1).

The mattress cover density is assumed to be 10 g/cm2 based on the
density of mixed cotton and synthetics (HERA 2003). 

Since there are no mattress specific residue transfer factors available
at this time, a default of 100% and 5% were used.  The 5% residue
transfer factor is based on the default residue transfer from treated
carpets and a confirmatory study is needed to support this assumption
(US EPA 2001).

The protection factor inhibiting exposure to Intersept ai in the
mattress from the use of a sheet or clothing is 50% based on PHED
protection factor for a single layer of clothing (US EPA 1998).

The child skin area contacting the mattress was assumed to 3,283 cm2
(50% of the total surface area of a toddler) (NAFTA guidance per US EPA
1997).

The adult skin area contacting the mattress was assumed to 9,220 cm2
(50% of the total surface area of a toddler) (NAFTA guidance per US EPA
1997).

Due to the lack of a chemical specific dermal absorption study, 100% was
used for DA.

The body weight of a child was assumed to be 15 kg.

The body weight of an adult was assumed to be 70 kg

Results

	Table 4.11 shows the calculation of the short and intermediate-term
dermal exposures and MOEs for children and adults contacting treated
mattress covers.  The only MOEs above the Target MOE of 100, and
therefore not a concern, is for adults and children contacting the cover
treated at the lowest rate (1%) and assuming 5% transfer to skin.  A
confirmatory transfer study is needed to support the 5% transfer
assumption.  

Table 4.11.  Short- and Intermediate-term Dermal Exposures and MOEs for
Children and Adults Contacting Treated Mattress Covers

Duration	% a.i.	Mattress density (mg/cm2)	Fraction transferred to skin
Skin surface area contacting mattress (cm2/day)	Protective factor

(%)	Dermal Absorption

(%)	ST and IT Exposure a 

(mg/kg/day)	MOE 

(Target MOE = 100) b

Children

ST/IT	5%	10	100%	3,283	50%	100%	54.7	1

ST/IT	5%	10	5%	3,283	50%	100%	2.7	23

ST/IT	1%	10	100%	3,283	50%	100%	10.9	6

ST/IT	1%	10	5%	3,283	50%	100%	0.5	114

Adults

ST/IT	5%	10	100%	9,220	50%	100%	32.9	2

ST/IT	5%	10	5%	9,220	50%	100%	1.6	38

ST/IT	1%	10	100%	9,220	50%	100%	6.6	9

ST/IT	1%	10	5%	9,220	50%	100%	0.3	190

a 	Equations used to estimate exposure are presented above.

b	MOE = NOAEL/exposure [Where: ST and IT dermal NOAEL = 62.5 mg/kg/day].


4.4.3	Data Limitations/Uncertainties tc \l3 "4.4.3	Data
Limitations/Uncertainties 

	There are several data limitations and uncertainties associated with
the residential handler and postapplication exposure assessments which
include the following:

Surrogate dermal and inhalation unit exposure values were from the
proprietary CMA (US EPA 1992) and Pesticide Handler Exposure Database
(US EPA 1998). These exposure data are of insufficient quality
therefore, AD requests that confirmatory monitoring data be generated to
support the values used in these assessments. 

The dermal absorption of 100% was assumed which resulted in conservative
dermal exposure estimates.  A dermal absorption study could be used to
refine the dermal exposures.

During the SMART Meeting (11/07/07) the registrant stated that the
targeted amount of ai applied to textiles (outer and underwear) is 0.75%
to 2% ai by weight of the fabric.  This specific application rate should
be specified on the label.

A confirmatory study is needed to verify the 5% transfer factor for
clothing and mattress covers.  The registrant indicated that they will
submit leaching/extraction data.  As soon as these data are submitted
and reviewed, the results will be incorporated into the assessment, as
appropriate.

5.0	RESIDENTIAL AGGREGATE RISK ASSESSMENT AND CHARACTERIZATION tc \l1
"5.0	RESIDENTIAL AGGREGATE RISK ASSESSMENTS AND RISK CHARACTERIZATION 

	

5.1	Acute and Chronic Dietary Aggregate Risk

	Based on the use patterns of Intersept ai, it is expected that there
will not be any dietary exposure.  Therefore, a dietary assessment was
not necessary to conduct.  

5.2	Short and Intermediate Term Aggregate Risk tc \l2 "5.2	Short-,
Intermediate-, and Long-Term Aggregate Risk 

	In order for a pesticide registration to continue, it must be shown
“that there is reasonable certainty that no harm will result from
aggregate exposure to pesticide chemical residue, including all
anticipated dietary exposures and other exposures for which there are
reliable information.”  Aggregate exposure is the total exposure to a
single chemical (or its residues) that may occur from dietary (i.e.,
food and drinking water), residential, and other non-occupational
sources, and from all known or plausible exposure routes (oral, dermal,
and inhalation).  However, this assessment only addresses non-dietary
residential aggregate exposures and risks.  Although, the Preliminary
Risk Assessment (PRA) of the RED will address the complete aggregate
assessment including both dietary and non-dietary residential exposures
and risks, it is identical to the non-dietary assessment since there is
no dietary or drinking water exposure potential. 

	In performing aggregate exposure and risk assessments, the Office of
Pesticide Programs has published guidance outlining the necessary steps
to perform such assessments (General Principles for Performing Aggregate
Exposure and Risk Assessments, November 28, 2001; available at
http://www.epa.gov/pesticides/trac/science/aggregate.pdf).  Steps for
deciding whether to perform aggregate exposure and risk assessments are
listed, which include: identification of toxicological endpoints for
each exposure route and duration; identification of potential exposures
for each pathway (food, water, and/or residential);  reconciliation of
durations and pathways of exposure with durations and pathways of health
effects; determination of which possible residential exposure scenarios
are likely to occur together within a given time frame; determination of
magnitude and duration of exposure for all exposure combinations;
determination of the appropriate technique (deterministic or
probabilistic) for exposure assessment; and determination of the
appropriate risk metric to estimate aggregate risk

  SEQ CHAPTER \h \r 1 Short- and Intermediate-Term Aggregate Exposures
and Risks

	Short- and intermediate-term aggregate exposures and risks were
assessed for adults and children that could be exposed to Intersept ai
residues from the use of products in non-occupational environments.  The
following lists summarize all of the non-dietary, non-occupation
potential sources of Intersept ai exposures for adults and children:

Adult Intersept ai exposures sources:

Applying  Intersept ai preserved paint in residential settings

Cleaning carpets with Intersept ai treated carpet shampoos

Wearing treated clothing

Sleeping on a treated mattress

	

Child Intersept ai exposures sources:

Post-application exposures to residues on carpeted surfaces cleaned with
treated shampoos

Post-application exposures to impregnated residues on hard surfaces
(i.e., vinyl floors)

Wearing treated clothing

Sleeping on a treated mattress

	The use patterns of the products and probability of co-occurrence must
be considered when selecting scenarios for incorporation in the
aggregate assessment.  For example, homeowner painting activities occur
only once or twice a year; therefore the probability of co-occurrence
and the potential for exposure to residues from this use with other
Intersept ai products on the same day is highly unlikely.    SEQ CHAPTER
\h \r 1 Because most of the Intersept ai products are used as a
materials preservative in the manufacturing of various materials and
exposure to some of these materials (e.g., mattresses and vinyl tiles)
can occur on a continuous basis, they were included in the aggregate
assessments.   It should be noted that based on the probability of
co-occurrence of the uses that have intermediate-term exposure
potential, it was determined that adult intermediate-term aggregate
assessment was not necessary to conduct.  Table 5.1 summarizes the
scenarios included in the short-term aggregate assessments.

Table 5.1:  Summary of Exposure Scenarios Included in the Short-and
Intermediate-Term Aggregate Assessments

Short-term Aggregate

Adults 	Dermal:

exposure to residues during carpet cleaning 

exposure to residues in mattresses preserved during manufacturing 

Inhalation:

exposure to residues during carpet cleaning 

Children	Dermal:

exposure to residues in fabrics/clothing preserved during manufacturing 

exposure to residues in mattresses preserved during manufacturing

exposure to residues in vinyl tiles preserved during manufacturing

Oral:

exposure to residues in fabrics/clothing preserved during manufacturing 

exposure to residues in polymers (toys) preserved during manufacturing

exposure to residues in vinyl tiles preserved during manufacturing

Intermediate- Term Aggregate

Children	Dermal:

exposure to residues in mattresses preserved during manufacturing

exposure to residues in vinyl tiles preserved during manufacturing

exposure to residues in carpet cleaner residues

Oral:

exposure to residues in vinyl tiles preserved during manufacturing

exposure to residues in carpet cleaner residues



  SEQ CHAPTER \h \r 1 It should be reiterated that the post-application
exposures to textile/clothing Intersept ai residues alone are of concern
to the Agency.  Incorporation of this scenario in the aggregate
assessment would result in risks of concern.  Therefore, the textile
scenario was not incorporated in the aggregate assessment.   If these
exposures did not result in risks of concern, then they would have been
included in the aggregate assessments instead of exposures to carpet
shampoo residues.  It should also be noted that for the mattress
scenario the MOE used in the aggregate assessment was based on the
minimum application rate because the MOE at the maximum application rate
was below the Agency’s Target MOE.  Incorporation of the maximum
application rate for the mattress scenario in the aggregate assessment
would result in risks of concern.  

Since the endpoint for each route of exposure was based on the same oral
study resulting in the same effects, all of the routes of exposure were
included in the aggregate assessment.  The Total MOE method outlined in
OPP guidance for aggregate risk assessment (September 1, 2000, Standard
Operating Procedure (SOP) for Incorporating Screening Level Estimates of
Drinking Water Exposure into Aggregate Risk Assessments) was utilized. 
This method was used because the oral, dermal and inhalation endpoints
have the same uncertainty factors or target MOEs of 100.   The general
equation used to estimate total or aggregate MOEs is:  

Aggregate MOE = 1 / ((1/MOEroute 1, scenario 1) + (1/ MOEroute1,
scenario 2) + (1/MOE route 1, scenario n))

 

Where, route represents oral or dermal exposures, and scenario
represents post-app carpet, mattress, etc.

Table 5.2 presents the resulting MOEs for the children’s short- and
intermediate-term aggregate assessments.    SEQ CHAPTER \h \r 1 Both ST
and IT aggregate MOEs for children were below the target MOE of 100 and
therefore a concern. Table 5.3 presents the resulting MOEs for the adult
short-term aggregate assessment.  The adult aggregate assessment was
above the Target MOE of 100 and therefore not a concern.

Table 5.2 Child ST and IT Aggregate Assessments

	MOEs

Exposure Duration	Mattress	Vinyl	Carpet Shampoo	Aggregate

	Dermal	Dermal	Oral	Dermal	Oral

	ST	110	1,500	12,000	2,100	620	86

IT	110	1,500	25,000	2,100	990	91

a: Aggregate MOE = 1/((1/MOE mattress dermal) + (1/MOE vinyl dermal) +
(1/MOE vinyl oral) + (1/MOE carpet dermal) + (1/MOE carpet oral))

Table 5.3 Adult ST Aggregate Assessment

	MOEs

Exposure Duration	Mattress	Carpet Cleaners	Aggregate	Target MOE

	Dermal	Dermal	Inhalation



IT	190	7,000	2,000,000	185	100

a: Aggregate MOE = 1/((1/MOE mattress dermal) + (1/MOE carpet dermal) +
(1/MOE carpet inhalation))

6.0	OCCUPATIONAL EXPOSURE ASSESSMENT tc \l1 "6.0	OCCUPATIONAL EXPOSURE
AND RISK 

	6.1	Summary of Registered Uses tc \l2 "6.1	Summary of Registered Uses 

	The exposure scenarios assessed in this document for the representative
uses selected by AD are shown in Table 6.1.  The table also shows
application rates associated with the representative use and the
appropriate EPA Registration number for the product label.  For
handlers, the representative uses assessed include use as a material
preservative.  

Table 6.1.  Representative Exposure Scenarios Associated with
Occupational Exposures to Intersept ai

Representative Use	Method of Application	Exposure Scenario	Registration
#	Application Rate

Material Preservatives

Paint1	Preservation of paint

Closed Systems

Professional painter

Brush/roller

Airless sprayer	Handler: IT dermal; ST and IT inhalation

Professional Painter:

ST dermal and inhalation	43670-1

	NA

0.1% - 5% a.i. by weight



1 Preservation of paint is representative of all Intersept ai material
preservative uses

	6.2	Occupational Handler Exposures tc \l2 "6.2	Occupational Handler
Exposures 

	The occupational handler scenarios included in Table 6.1 were assessed
to determine dermal and inhalation exposures.  Based on information
provided by the registrant during the SMART meeting (11/7/07) and the
label use directions, it appears that the Intersept ai product is
applied via closed delivery systems (e.g., from sealed tote tanks to
vats via metering pumps for liquid materials or hoppers for polymer bead
materials).  AD has recently developed definitions and exposure
methodology guidance when working with closed loading and delivery
systems in commercial and industrial settings.  

Closed loading systems are engineering controls that are “…designed
to prevent human exposure and should not require human intervention to
eliminate exposure” (Fong 2003).  Closed transfer systems that require
the worker to open pour the concentrate into a transfer system are not
considered under this definition of closed loading systems because the
initial exposure for the open pour will require a quantitative
assessment.  Although closed loading and delivery systems are designed
to prevent or eliminate exposure, zero exposure is difficult to obtain. 
Even though analytical techniques can measure residues at extremely low
levels, for practical purposes at some point these residues can be
considered negligible or minimal.  To account for the fact that some
residues are available for dermal contact (and to a lesser degree
available for inhalation exposure), EPA is requiring that appropriate
personal protective equipment (PPE) be worn or available to the worker. 


Negligible exposure can be considered to result from the use of systems
that are designed to drip less than 2 mL per coupling as in dry coupling
or metering pumps that are closed on both ends.  The second category,
minimal exposure, has been established because some closed systems are
not entirely enclosed or have not been engineered to reduce drips to 2
mL, but for practical purposes effectively reduce exposure such that
risks are not of concern.  Minimal exposure can be considered to result
from closed systems that are designed to prevent or eliminate inhalation
and dermal exposure but are not engineered to a specification (e.g.,
volume expected to be discharged).  

 

In the case of Intersept ai products, AD expects that occupational
exposures will be negligible or minimal assuming that the appropriate
PPE (i.e., long pants, long-sleeved shirts, and chemical resistant
gloves) and label-specified closed delivery and loading systems such as
sealed tanks via metering pumps and hoppers, as appropriate, are
consistently utilized.  Therefore, a quantitative exposure and risk
assessment is not warranted and the risks can be considered not a
concern.  However, since the labels do not specifically state to use
with closed delivery systems (e.g., metering pumps and hoppers) they
will need to be updated with appropriate closed system language and PPE
(i.e., goggles, face shield and chemical resistant gloves).  If the
registrant does not want this limitation (e.g., metering pumps and
hoppers), then an open pour handler assessment must be conducted by the
Agency prior to the RED decision.

	

	6.3   Professional Painter	

	The short-term inhalation and dermal professional painter exposures
were assessed.  Only short-term exposure durations (1 to 30 days) were
estimated because it was assumed that professional painters would not
use Intersept ai treated paint daily therefore exposures would occur on
an intermittent basis.

Exposure Calculation Assumptions

Unit Exposure Values:  There are no chemical-specific exposure data to
assess professional handler exposures however surrogate data are
available for painting with a brush and an airless sprayer.  The
surrogate data are based on PHED data for painters wearing no gloves or
respiratory protection.

For the brush/roller scenario, the PHED dermal and inhalation unit
exposure values for a residential handler applying a pesticide using a
paint brush were used.  The test subjects were painting a bathroom with
a paint brush.  The dermal unit exposure value (180 mg/lb a.i.)
represents a handler wearing long pants, long sleeves and no gloves. 
The inhalation unit exposure value (0.28 mg/lb a.i.) represents a
handler wearing no respiratory protection. 

For the airless sprayer scenario, the PHED unit exposure values for a
residential handler applying a pesticide using an airless sprayer were
used.  The test subjects were staining the outside of a house with an
airless sprayer.  Although these exposures may differ slightly from
exposures of painters of Intersept ai persevered products, these data
are judged to be adequately representative.  The dermal unit exposure
value (38 mg/lb a.i.) represents a handler wearing long pants, long
sleeves and no gloves.  The inhalation unit exposure value (0.83 mg/lb
a.i.) represents a handler wearing no respiratory protection. 

Quantity handled/treated: The quantities handled/treated were estimated
based on information from various sources and assumptions. 

For the brush/roller in paint applications, it is assumed that 50 lbs
(approximately 5 gallons) of treated paint will be used.  

 For the airless sprayer in paint applications, it is assumed that 500
lbs           (approximately 50 gallons) of treated paint will be used. 


Results

	Table 6.2 presents the calculations of the dermal and inhalation doses
and MOEs for a professional painter working with treated paint.  The
short-term dermal and inhalation MOEs estimated for painters at the
lower application rate are above the target MOEs of 100 and 1000 and not
a concern.  However, the short-term dermal MOEs estimated for painters
at the maximum application rate are below the target MOE of 100 and
therefore a concern.  Note that all of the inhalation MOEs are above
1000, therefore an inhalation specific toxicity study is not warranted
for this scenario.

Table 6.2 Intersept ai Short-Term Professional Painter Exposures and
MOEs

Exposure Scenario	Application Method	Application Ratea	Quantity Handled
per dayb	Dermal Unit Exposure

(mg/lb a.i.)	

Inhalation Unit Exposure

(mg/lb a.i.)	Dermal Daily Dose (mg/kg/day) c	Inhalation Daily Dose
(mg/kg/day) c	Dermal MOE d

(Target MOE = 100)	Inhalation MOE d

(Target MOE = 100)	Total MOE

Painting	Paint brush	0.1% ai by wt	50 lbs	180	0.28	0.13	0.00020	490
310,000	490



5% ai by wt	50 lbs	180	0.28	6.43	0.010	10	6,300	10

	Airless sprayer	0.1% ai by wt	500 lbs	38	0.83	0.27	0.0059	230	11,000
230



5% ai by wt	500 lbs	38	0.83	13.6	0.30	5	210	5

a	Application rates are based on the minimum and maximum application
rates determined from EPA registered labels (see Table 6.1).

b	Amount handled per day values are standard EPA assumptions	

c	Daily dose (mg/kg/day) = [unit exposure (mg/lb a.i.) x application
rate (% a.i. weight or lb ai/gal) x quantity handled (lb/day or gal/day)
x absorption factor (1.0 for dermal and  inhalation)]/ Body weight (70
kg).

d	MOE = NOAEL / Daily Dose.  [Where short-term dermal and inhalation
NOAEL = 62.5 mg/kg/day]. Target MOE = 100.  Note: if inhalation MOE is
below 1000 then an inhalation specific toxicity study may be warranted

e	Total MOE = 1/((1/MOEdermal) + (1/MOEinhal))

	

6.4	Occupational Post-application Exposures tc \l2 "6.3	Occupational
Post-application Exposures 

	No occupational post-application exposures are assumed to occur for the
scenarios summarized in Table 6.1; any post-application exposures from
these uses are expected to occur in a residential setting.  These
exposure scenarios are assessed in the residential exposure assessment
in Section 4.

6.5	Data Limitations/Uncertainties tc \l2 "6.8	Data
Limitations/Uncertainties 

	There are several data limitations and uncertainties associated with
the occupational handler exposure assessments which include the
following:

Based on information provided by the registrant during the SMART meeting
(11/7/07) and the label use directions, it appears that the Intersept ai
product is applied via closed delivery systems (e.g., from sealed tote
tanks to vats via metering pumps for liquid materials or hoppers for
polymer bead materials). However, since the labels do not specifically
state to use with closed delivery systems (e.g., closed totes, metering
pumps and automated hoppers) they will need to be updated with
appropriate closed system language and PPE (i.e., goggles, face shield
and chemical resistant gloves).  If the registrant does not want this
limitation (e.g., closed totes, metering pumps and automated hoppers),
then an open pour handler assessment must be conducted by the Agency
prior to the RED decision.  Furthermore, the registrant will need to
provide amount handled information.  

Surrogate dermal and inhalation unit exposure values were taken from the
Pesticide Handler Exposure Database (US EPA 1998).  These data are of
poor quality therefore, AD requests that confirmatory monitoring data be
generated to support the values used in these assessments.  

The quantities handled/treated were estimated based on standard AD
assumptions that can be further refined from input from registrants. 

The dermal absorption of 100% was assumed which resulted in conservative
dermal exposure estimates.  A dermal absorption study could be used to
refine the dermal exposures.

7.0	REFERENCES tc \l1 "7.0	REFERENCES  

Fong, H.R.  2003. An Overview of Closed System Use in California
2001-2002.  Report HS-1849. California Environmental Protection Agency,
Department of Pesticide Regulation, Worker Health and Safety Branch. 
June 2003.

  SEQ CHAPTER \h \r 1 HERA.  2003.  Human and Environmental Risk
Assessment, Guidance Document Methodology, April 22, 2002 (  HYPERLINK
"http://www.heraproject.com/files/Guidancedocument.pdf" 
http://www.heraproject.com/files/Guidancedocument.pdf ).

U.S. Environmental Protection Agency (US EPA).  1997a.  Standard
Operating Procedures (SOPs) for Residential Exposure Assessments.  EPA
Office of Pesticide Programs(Human Health Effects Division (HED). 
December 18, 1997.

U.S. Environmental Protection Agency (US EPA).  1997b.  Exposure Factors
Handbook. Volume I-II.  Office of Research and Development.  Washington,
D.C.  EPA/600/P-95/002Fa.

U.S. Environmental Protection Agency (US EPA).  1998.  PHED Surrogate
Exposure Guide.  Estimates of Worker Exposure from the Pesticide Handler
Exposure Database Version 1.1.   Washington, DC:  U.S. Environmental
Protection Agency.

U.S. Environmental Protection Agency (US EPA).  1999.  Evaluation of
Chemical Manufacturers Association Antimicrobial Exposure Assessment
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