**PHASE 5 Comments on the pRELIMINARY rISK aSSESSMENT FOR ALKYLBENZENE
SulfonateS (ABS)**

**Docket #EPA-HQ-OPP-2006-0156**

**SUBMITTED BY THE DDBSA STEERING COMMITTEE/JOINT VENTURE**

**NOTE:** The DDBSA Steering Committee/Joint Venture (JV) has recently
been made aware that a SIDS Dossier, sponsored by the US EPA, has been
compiled and the hazard data conclusion was agreed upon at SIAM 20 for a
series of Linear Alkylbenzene Sulfonates (LAS). This information was
supplied by industry consortium of LAS producers (CLER) to the JV and
the JV provided the document to the Agency in an email memo from Susan
Little to Heather Garvey dated May 30, 2006. The SIDS assessment
includes the following chemicals:

> 1322-98-1 Decylbenzene sulfonic acid, sodium salt;
>
> 25155-30-0 Dodecylbenzene sulfonic acid, sodium salt;
>
> 26248-24-8 Tridecylbenzene sulfonic acid, sodium salt;
>
> 27636-75-5 Undecylbenzene sulfonic acid, sodium salt;\
> 68081-81-2 C~10-16~ Monoalkylbenzene sulfonic acid, sodium salt;\
> 68411-30-3 C~10-13~ Alkylbenzene sulfonic acid, sodium salt;\
> 69669-44-9 C~10-14~ Alkyl deriv benzene sulfonic acid, sodium salt;\
> 85117-50-6 C~10-14~ Monoalkylbenzene sulfonic acid, sodium salt;\
> 90194-45-9 C~10-13~ Alkyl deriv benzene sulfonic acid, sodium salt;
> and\
> 127184-52-5 4-C~10-13~-sec Alkyl deriv benzene sulfonic acid, sodium.

In addition, as noted in previous comments, a review of Linear Alkyl
Benzene Sulfonic Acids (LAB) was included in the EPA's High Production
Volume Chemical Challenge program. The JV is relying on these documents
for some of its responses as indicated below.

**COMMENT 1.** Page 4 -- Last Paragraph: "Available acute toxicity data
show that alkylbenzene sulfonates are not highly acutely toxic
(Categories III-IV), are irritating to the eye and skin (categories I
and II, respectively), and they are weak-moderate skin sensitizers."

> Response: DDBSA is not a skin sensitizer based on extensive human
> exposures from laundry and dish detergents. Further, the SIDS Dossier
> for LAS provides three negative guinea pig studies, listed in the
> IUCLID dossier (pages 268-269), and a report of 2 human HRIPT tests
> that were negative, listed on pages 305-306. Note also that the
> conclusion on page 25, "LAS does not have significant skin
> sensitization properties" was accepted in this review process. The
> overwhelming evidence from the available animal and human studies is
> that LAS (and DDBSA) are not skin sensitizers. The conclusion reached
> in the RED review, therefore, should be changed. For additional
> details, please see our reply to the Response to Errors Only comments
> below and comments provide by CLER.

**COMMENT 2.** Page 12 -- Physical and Chemical Properties

> The following paragraph appears on Page 8:
>
> *Dodecylbenzene sulfonic acid (27176-87-0) and sodium dodecylbenzene
> sulfonate (25155-30-0) have tolerance exemptions as specified in 40
> CFR 180.940 (b) and (c). Both dodecylbenzene sulfonic acid and sodium
> dodecylbenzene sulfonate have limitations for the ready-to-use end-use
> concentration not to exceed 400 ppm and 430 ppm, respectively for food
> processing equipment and utensils. However, dodecylbenzene sulfonic
> acid has a much lower limitation of 5.5 ppm for use on dairy
> processing equipment.*
>
> The JV would like to raise two points regarding this information.
> First, it is not clear to the JV why the distinction is made between
> "food processing equipment" and "dairy processing equipment" in the
> regulation since dairy equipment is, in fact, food processing
> equipment. Second, a concentration of 5.5 ppm is not considered to be
> an adequate sanitizer concentration as the length of time for adequate
> sanitization would be extensive, if even feasible. Proper sanitization
> of dairy equipment and other food processing equipment requires
> approximately 200 to 400 ppm of DDBSA. The JV agrees with the Agency
> that the risk assessments should be performed on the higher
> concentrations.

**COMMENT 3.** Page 12 -- Physical and Chemical Properties

> Response: Please see our reply to the Agency's Response to Errors Only
> Comments below regarding the molecular weight and molecular formulae
> in Table 1. Also, we have been informed by the LAS Producers that the
> chemical structures as shown are incorrect -- please see comments from
> the LAS Producers group, CLER.

**COMMENT 4.** Table 13 (Page 36-38) -- Short and Intermediate-Term
Inhalation Risks for Occupational Handlers

> Response: The use of high volume (e.g. 10,000 gallons/day) exposure to
> cleaning solutions is inappropriate because these procedures are
> performed with minimal human exposure. For Cleaning in Place (CIP)
> procedures, the following has been prepared to explain the procedures
> and potential worker exposures. As clearly shown, worker exposure to
> more than a minimal volume of cleaning solution does not occur.
> Further, when workers use concentrated solutions (prior to dilution),
> PPE is always required. The JV believes the other scenarios in Table
> 13 for which high volume exposure is assumed also use procedures that
> provide for only minimal worker exposure.

Discussion of Exposure Potential to Workers during Cleaning in Place
(CIP) Operations-

Prepared by F.A. Heitfeld (JohnsonDiversey)

*[Overview of CIP]{.underline}*

> Cleaning in Place (CIP) operations are common in large industrial
> manufacturing facilities. While associated with the food, beverage,
> brewing, and dairy industries, CIP operations occur in a wide variety
> of industrial applications including pharmaceuticals and in industrial
> chemical production. CIP applications often utilize multiple cleaners,
> not all of which are EPA regulated pesticides.
>
> CIP systems automate the cleaning and sanitization process for
> industrial process equipment, such as product lines, tanks, vessels,
> etc. Some of the advantages of these systems are: [^1]

1.  CIP allows easy cleaning of process equipment that is not easily
    accessible to its operators.

2.  CIP eliminates the need to disassemble equipment for cleaning.

3.  CIP prevents worker and environmental exposure to harmful production
    or cleaning chemicals.

4.  Automatic cleaning prevents contamination of the production process.

5.  CIP systems provide more consistent and reproducible cleaning.

6.  The cleaning process is automated possibly reducing staffing
    requirements for the process line.

7.  Production down time can be reduced.

8.  Minimize the amount of cleaners and water used to clean.

> CIP systems consist of the following major elements.
>
> 1\. PLC (Programmable Logic Controllers)- this is a programmable unit
> that initiates and controls the CIP operations in a production
> facility.
>
> 2\. Chemical storage- This is the area where concentrated cleaners and
> biocides are stored. Typical storage containers range from Drums
> (30-55 gallon) and totes (220-330 gallon) up to storage tanks that are
> filled from tank trucks or rail cars. Some systems pump an aliquot of
> concentrate into a separate tank (day tank) before use. This prevents
> contamination of the concentrate if the system malfunctions. There is
> no additional exposure since the transfer process is closed and
> pumping is automatically controlled by the system.

3.  Chemical Pump --Chemical pumps are normally PLC controlled via time
    or conductivity. The pump controls total flow through the CIP loops
    and plays an important role in chemical dilution. Time based dosing
    systems add chemical based on the chemical pump's capacity to pump x
    volume in y amount of time. Conductivity based systems add chemicals
    via a conductivity probe which controls the chemical pump via a PLC.

4.  Recirculation -- CIP systems start with a cold water rinse. The
    rinse is designed to first verify all connections have been
    correctly made. Second it removes loose and soluble soils. There can
    be up to 3 individual rinse steps. Rinses are bursts of limited
    amounts of water to remove loose and soluble soils. Next, water is
    added to the system and re-circulation is established. Once
    re-circulation is established, the cleaner is added to the system.
    When completed, heat is applied to the solution, via a heat
    exchanger, to establish the correct cleaning temperature -- all
    controlled by the PLC. The PLC recirculates the solution for the
    predetermined amount of time. The cleaning solution is drained. 1-3
    cold water burst rinses to remove cleaning solution. The sanitizer
    is circulated after all cleaning steps are completed.

5.  Cleaning Circuits- Most CIP systems consist of a number of
    individual circuits which typically correspond to a discrete section
    of the production line (e.g. one tank and its associated piping or a
    single transfer pipeline). All circuits use a known volume of water.

> The design of CIP systems are customized for each individual facility
> based on the needs and requirements of the process. The number of
> circuits depends on the size of the production facility, how many
> processing lines, tanks, fillers, etc being cleaned and the time
> available each day for cleaning. Large facilities, that cannot
> tolerate being out of production for very long, may have two or more
> independent CIP systems in use at one time. Each CIP system would
> typically clean one circuit at a time.
>
> Circuits are often divided into two types:
>
> 1\. Line circuits- CIP circuits designed to clean the piping used in
> the production process. These circuits tend to use the most water.
> This can be between 100 and 1000 gallons depending on the length of
> piping and its diameter. Most common circuits are between 100 and 300
> gallons.
>
> 2\. Tank circuits- CIP circuits designed to clean a tank and the
> process piping to the tank. Usually, these have a 1 tank per circuit
> limit. Tank circuits typically require only 40-100 gallons to clean.
> The variable here is the size of the tank and the volume of its
> associated piping. The amount of CIP solution needed for the circuit
> must be sufficient to fill the circuit piping and the bottom of the
> tank (to maintain the prime for the pump) as well as to cover the
> walls of the tank. The tank itself is never filled completely with CIP
> cleaners. It is possible for a 20,000 gallon tank to be cleaned with
> only 50 gallons of solution.
>
> Tanks are cleaned by spraying the cleaning solution through "spray
> balls" which are high technology sprinklers designed to spray all
> interior surfaces of the tank. Spray balls have various spray patterns
> depending on the type of tank, i.e. horizontal versus vertical, tanks
> with mixers, fixed blades, etc. This operation is essentially
> enclosed; however, some systems require that the tank be vented to
> prevent implosion if the temperature of the cleaning liquid changes
> from hot to cold.
>
> The overall design of CIP systems can be broken down in to two main
> types:
>
> 1\. Once through Systems called Single Use Systems- The cleaning
> solution is sent through the system and then directly drains into the
> facility waste water management system.
>
> 2\. Recirculation systems called Re-Use Systems- the cleaning solution
> is re-used many times to clean multiple circuits before draining into
> the facility waste water management system. Re-Use systems typically
> require less product than single use systems.

*[CIP Cleaning Cycles and the use of Biocides:]{.underline}*

> Biocide use is only a small part of the CIP process. The standard
> progression of cycles consists of the following:
>
> 1\. Rinse with water to remove soil from the process equipment.
>
> 2\. Detergent treatment to remove remaining soils (may be heated)
>
> 3\. Water rinse to remove detergent chemicals (may be heated).
>
> 4\. Acid wash or Acid rinse for hard water areas or high calcium foods
> (may be heated)
>
> 5\. Water rinse to remove acid detergent
>
> 6\. Sanitizing with no rinse (usually at ambient temperatures)
>
> Note: If using an acid sanitizer steps 4 and 5 may be eliminated or
> used less frequently depending on scale formation.
>
> Each plant/facility has its own customized program for cleaning and
> sanitizing based on its unique requirements. The actual duration of
> the sanitizing cycle is short (1-2 minutes typical, 5 minutes
> maximum).

*[Worker Exposure to Chemicals during CIP Operations]{.underline}*

> CIP systems are designed to limit worker exposure to cleaning
> chemicals while still insuring a high level of hygiene to critical
> industrial processes. The majority of CIP operations are automated and
> do not require workers to come into contact with the cleaning
> chemicals. There is, however, some potential for worker contact in the
> following areas:
>
> 1\. Connection of Totes and Drums to the CIP system: Many CIP systems
> use concentrated cleaning products in totes or drums. These have to be
> manually installed into the system. This operation is analogous to the
> pump liquid use pattern. Once the tote or drum is in place, the worker
> opens the container and installs a pickup tube or probe that conveys
> the concentrated product into the CIP system for dilution. Totes
> either use the probe or pick up tube or a connection to the tote
> outlet valve. Once installed, the worker can leave the area.
> Conversely, when the drum or tote is empty, the probe or tube is
> withdrawn and transferred to a fresh container. Please note, that
> since many of these products are corrosive, significant PPE (e.g.
> goggles, gloves) is required under OSHA regulations.
>
> In most plants, the use-period for a drum or tote ranges from 1 week
> to 1 month. Thus, changeover operations occur on a regular, but
> infrequent basis.
>
> Possible areas of worker exposure include:
>
> a\. Dermal exposure to drainage of concentrated product from the
> pick-up tube as it is removed from the tote or drum.
>
> b\. Dermal exposure to residual concentrated product on the outside of
> the pick-up tube during transfer from the empty to the full tote or
> drum.
>
> c\. Inhalation exposure to vapors from volatile materials released
> either from the open totes/drums or from the residual product
> associated with the pickup tube.
>
> The exposure scenarios described above are NOT volume dependent. Once
> installation is completed, the worker can leave the area and conduct
> other duties. The actual amount of time involved in removing a spent
> container and installing a new container is typically 5-10 minutes on
> a weekly to monthly basis. Thus, the actual volume of product pumped
> through the system is irrelevant to the amount of worker exposure in
> this case.
>
> 2\. Delivery of bulk concentrates to storage tanks within the
> facility: Larger processing facilities may take delivery of cleaning
> chemicals in bulk from either trucks or tank cars. In these cases, the
> material is pumped from the delivery vehicle into a storage tank in
> the facility.
>
> Possible areas of worker exposure include:
>
> a\. Dermal exposure to drainage of concentrated product from the hoses
> used to transfer product from the delivery vehicle to the facility
> storage tank. If dry-break couplings are used, exposure should be
> minimal.
>
> b\. Inhalation exposure to vapors from volatile materials released if
> product spills during transfer operations.
>
> The exposure scenarios described above are also NOT volume dependent.
> Exposure will likely occur once the product transfer is completed and
> the hose is disconnected for storage. If dry-break couplings are not
> used, some product spillage may occur resulting in potential worker
> exposure to the concentrate. The amount of spillage (if any) will be
> dependent on the size of the hose, but not on the amount of material
> transferred to the facility. Again, significant PPE is required under
> OSHA regulations since many of these materials are corrosive.
>
> 3\. Exposure to use-dilution product and vapors during CIP system
> changeovers. CIP systems require a positive disconnect from the
> production line in food and beverage plants to prevent accidental
> contamination of production product with CIP cleaning and sanitizing
> solutions. At the end of a CIP cycle, the system is shut-off, and a
> worker must physically disconnect the piping connecting the CIP system
> to the production line in order to prevent contamination of product
> with CIP chemicals. Potential exposure to the sanitizing solution may
> occur if there is drainage of use-solution from the piping during this
> operation. It typically takes only 1-2 minutes to move a plumbing or
> hose connection but may have to be repeated 5-10 times if multiple
> circuits are involved. Since CIP cleaning typically occurs once per
> day, only one shift would be involved in this operation.
>
> 4\. Exposure to use-dilution vapors/mists during tank cleaning: In
> some systems, tank cleaning has the potential for limited worker
> exposure to vapors or mists from use-dilutions of some cleaning
> products. CIP cleaning solutions (not biocides) are often prepared at
> elevated temperatures. To prevent tank implosions when a cold solution
> is sprayed into a hot tank, some of the access ports are left open to
> allow the air pressure inside the tank to equalize with the pressure
> outside of the tank. Large tanks are more vulnerable than smaller
> tanks.
>
> A worker in the immediate vent area may be exposed to mists or
> splashing from these vents from the *diluted* cleaning product. Since
> CIP systems are automated, workers are typically not in the area
> during tank cleaning. If a worker was present, exposure to the biocide
> solution is expected to be brief- at most, exposure would only occur
> for the 1-2 minutes duration of a biocide CIP cycle. Recently
> implemented best practice includes the installation of a temporary
> tank door to minimize escape of the CIP solution while allowing for
> adequate venting to prevent tank collapse. All facilities require
> respiratory protective equipment if tank entry is necessary, as these
> are classified by OSHA as confined spaces.

*[Recommendations:]{.underline}*

> 1\. Worker exposure during CIP operations is limited. One of the
> advantages of these systems is to reduce worker contact with cleaning
> chemicals by automating the dilution and cleaning processes. The
> Agency's assumption that workers are exposed to the equivalent to the
> exposure from manual pouring 10,000 gallons per day is unreasonable.
>
> 2\. Routine but occasional worker exposure to cleaning chemicals in
> CIP systems should be presumed to occur during connection and/or
> disconnection of the cleaning concentrate container to the CIP system.
> Exposure to the use-dilution may occur when the CIP system is manually
> disconnected from the production line.
>
> a\. Worker exposure from both of these operations is NOT expected to
> be volume dependent for routine CIP operations.
>
> b\. Concentrate reservoirs (totes or drums) are replaced approximately
> once a week to once a month in most systems. This operation only takes
> 5-10 minutes. Since most CIP biocidal concentrates are corrosive, PPE
> is required under OSHA regulations. Workers do not remain in the area
> after the connections are made and the "pumping" occurs over a period
> of days or weeks, [and]{.underline} only when the CIP system is in
> operation.
>
> c\. During the positive disconnect of the CIP system, some worker
> exposure to the use-dilution of the biocide product. While the CIP
> system is turned off during the change-over, some drainage may occur.
> Workers would be exposed to the product during the 1-2 minutes
> required to move the pipe or hose connection. This operation may have
> to be repeated 5-10 times if multiple circuits are involved. The
> frequency of this operation is approximately once per day (\< once per
> shift).

**COMMENT 5.** Table 13 (Page 37) -- Shower Stalls and Toilets

> Response: According to the Agency's Response to Errors Only Comments,
> the Shower Stalls and Toilets scenario is developed from Product
> Registration 3635-279. A review of this label indicates that the
> product is 15.52% DDBSA as stated by the Agency. However, there are no
> "Wiping" procedures on the label that use concentrated product (1.49#
> a.i./gallon) and 1 liter (0.26 gallons/day). That is, all wiping
> procedures occur after dilution of the product to 1-2 oz/gal.

**COMMENT 6.** Section 11.0 Deficiencies/Data Needs -- Ecological Data
Gaps and\
Label Hazard Statements for Terrestrial and Aquatic Organisms

> The Agency indicates that Acute Freshwater Fish and Acute Freshwater
> Invertebrate studies are required. The Agency indicates that an
> environmental hazard statement for manufacturing use products is
> required for fish and aquatic invertebrates.
>
> Response: This requirement is based on a lack of information for
> toxicity of C12-C16 BSA to fish and an EC50 of \< 1.0 ppm for C14/16
> for invertebrates. According to CLER, benzene sulfonic acid, C10-C16
> alkyl derivatives (CAS RN 68584-22-5) contain less than 1% of the C15
> or C16 homologues, the C14 component is a minor fraction of the
> composition (\< 15%) and the average alkyl chain lengths for LAB
> sulfonic acids have the same range (C11.3-C12.6) as LAS and likely
> have the same overall weighted average chain length as LAS, C11.7.
>
> Data from the LAS SIAR and/or the HPV submission for LAB, report at
> least 16 fish studies and 17 freshwater aquatic invertebrate studies
> on commercially relevant LAS and LAB (average alkyl chain length
> approximately 11.7) that followed standardized (EPA and OECD
> guideline) test methods. The fish LC50 values ranged from 1.67 to 7.7
> mg/L for LAS and from 3 to 10 mg/L for the LAB sulfonic acids. The
> invertebrate EC50 values range from 1.62 to 9.3 mg/L for LAS and from
> 2.9 to 12 mg/L for LAB, including the C10-C16 benzene sulfonic acid
> and dodecylbenzene sulfonic acid.
>
> These data demonstrate that no environmental hazard statement is
> required for DDBSA per se, because the EC50 values for fish and
> aquatic invertebrates are all greater than 1 mg/L. Further, these data
> indicate that additional testing of DDBSA in aquatic species is
> unnecessary. It should be noted that the majority of the current
> labels from JV-Member Companies include the statement, "This product
> is toxic to fish" based on the mixture of DDBSA with phosphoric acid.

**COMMENT 7.** Section 11.0 Deficiencies/Data Needs --
Residential/Occupational Data Gaps

> The Agency indicates a need for worker exposure studies that evaluate
> inhalation exposure for indoor uses.
>
> Response: The industry has several task forces generating data
> pertinent to this request that should provide improved values for
> these assessments.

**COMMENTS: ALKYLBENZENE SULFONATES (ABS) TOXICOLOGY CHAPTER**

**FOR THE REREGISTRATION ELIGIBILITY DECISION (RED) DOCUMENT. PC CODE:
079010, 190116 AND 098002. CASE NO. 4006. DP BARCODE: D327886**

The Agency has changed the section on Page 10 related to the inhalation
studies in monkeys to read as follows: *"In this published study, the
detergent was dried and micronized to make it respirable. However, it
should be noticed that most uses of this detergent are in liquid form.
It is a common misconception that the small particle size used in an
animal study (MMAD of 1-3 um in acute studies, 1-4 um in multiple
exposure studies) has no relevance to the large particle size that comes
from medium to coarse powdered material or a liquid-powder mix during
use. Detergents are typically mixed with large quantities of water
before use. When the aqueous mix is used, droplets rapidly shrink as
they fall due to water evaporation. The degree of shrinkage depends on
temperature, relative humidity, particle size, and the length of time
that the droplets are suspended in the air. Since humans are capable of
inhaling particles \>100 um, it is reasonable to expect a significant
portion of these particles to be inhaled. While most large particles are
captured in the nose, some are capable of reaching the lungs. Large
particles have the potential to do considerable local damage if they are
respirable because of the volume of material they contain."*

> Response: Please see detailed comment in our reply to the Agency's
> Response to Errors Only Comments below and in the previous comments
> provide by S. Little to H. Garvey on May 30, 2006.
>
> In addition, the summary of the study should include reference to the
> lung lesions in groups 2, 8 (LOAEL selected by the Agency), 9, 10, 11,
> and 12 that included chronic bronchiolitis characterized by
> infiltration of mononuclear macrophages and lymphocytes, bronchiolar
> fibrosis, nonsuppurative alveolitis, hypertrophy and hyperplasia of
> the bronchiolar epithelium (including squamous metaplasia). Further,
> the summary should conclude that the lung lesions were considered to
> be a response to irritation from the dust and/or related to the enzyme
> added. It is reasonable to conclude that the body weight change in the
> 10 mg/m^3^ (+ enzyme) used by the Agency to select the LOAEL was a
> result of the lung lesions and not chemical toxicity. Based on all of
> the above information, the selection of the NOAEL for this study
> should be considered highly conservative.

**COMMENTS: OCCUPATIONAL AND RESIDENTIAL EXPOSURE ASSESSMENT OF
ALKYLBENZENE SULFONATES (ABS) FOR THE REREGISTRATION ELIGIBILITY
DECISION DOCUMENT (RED). CASE NO. 4006. DP BARCODE: D327732**

Page 6 -- Data Limitations and Uncertainties -- First Bullet: "Most of
the CMA data are of poor quality; therefore, AD requests that
confirmatory monitoring data be generated to support the values used in
these assessments."

> Response: The industry has several task forces generating data
> pertinent to this request that should provide improved values for
> these assessments. Further, DDBSA-specific monitoring would be
> extremely difficult because of the extensive use of DDBSA in laundry
> and dish detergents.

**COMMENTS: ENVIRONMENTAL FATE ASSESSMENT OF ALKYLBENZENE SULFONATES
(ABS) FOR THE REREGISTRATION ELIGIBILITY DECISION DOCUMENT (RED). CASE
NO. 4006. DP BARCODE: D323968**

**No comments for this document**

**COMMENTS: ECOLOGICAL HAZARD AND ENVIRONMENTAL RISK ASSESSMENT OF
ALKYLBENZENE SULFONATES (ABS) FOR THE REREGISTRATION ELIGIBILITY
DECISION DOCUMENT (RED). PC CODE: 079010, 190116 AND 098002. CASE NO.
4006. DP BARCODE: D323970**

Please see above comments, included for the Preliminary Risk Assessment,
related to the requirements for fish and aquatic invertebrate testing
and label requirements.

**COMMENTS: INERT INGREDIENT DIETARY RISK ASSESSMENT FOR LINEAR
ALKYLBENZENE SULFONATE REREGISTRATION ELIGIBILITY DECISION DOCUMENT
(RED). CASE NO. 4006. DP BARCODE: D324036**

**No comments for this document**

**COMMENTS: RESIDENTIAL EXPOSURE INERT ASSESSMENT OF ALKYLBENZENE
SULFONATES (ABS) FOR THE REREGISTRATION ELIGIBILITY DECISION DOCUMENT
(RED). CASE NO. 4006. DP BARCODE: D327733**

**No comments for this document**

**COMMENTS: DIETARY RISK ASSESSMENT FOR ALKYLBENZENE SULFONATES (ABS)
FOR THE REREGISTRATION ELIGIBILITY DECISION DOCUMENT (RED). CASE NO.
4006. DP BARCODE: D327731**

**No comments for this document**

**COMMENTS: PRODUCT CHEMISTRY SCIENCE CHAPTER FOR DODECYLBENZENE
SULFONIC ACID, C10-C16 DERIVATIVES AND SODIUM SALT. CASE NO. 4006. DP
BARCODE: D327731**

The Agency changed the water solubility from the original draft version
for C10-C12 DDBSA (CAS RN 68584-22-5) to [400 grams/liter]{.underline}
but did not similarly change the water solubility of C12 DDBSA (CAS RN
27176-87-0), retaining the value of 0.7 mg/L.

**COMMENTS: RESPONSE TO ERROR COMMENTS ON THE ALKYLBENZENE SULFONATES
(ABS) PRELIMINARY RISK ASSESSMENT. PC CODE: 079010, 190116 AND 098002.
CASE NO. 4006. DP BARCODE: D323960**

1\. Following is the argument offered by EPA's reviewing toxicologist in
response to our Errors Only Comment that it is inappropriate to conclude
that DDBSA is a mild to moderate skin sensitizer:

> *The Agency has provided the citation that supports the "weak-moderate
> skin sensitizer" classification. Nusair TL, PJ Danneman, J Stotte, PHS
> Bay (1988) Consumer Products: Risk Assessment Process for Contact
> Sensitization, Toxicologist 8:258. This study conducted two
> experiments in guinea Pigs. In the first experiment, they applied a
> paste of LAS to the skin of guinea pigs at induction at concentrations
> of 2-100% and then challenged them at concentrations of 1-2%. In the
> second experiment, a prototype liquid laundry detergent (10% LAS) was
> applied to the skin of guinea pigs, and induced sensitization at a
> challenge concentration of 1% (0.1% as LAS). From both experiments,
> They concluded that LAS is weak to moderate sensitizer (Toxicity
> Category III).  In addition, there was evidence of sensitization in
> the monkey inhalation study, which supports the Agency's
> classification.*

The data cited in the above paragraph for guinea pig studies are
actually included on page 486 in the following citation and the stated
Toxicologist citation does not appear to cite the specific data
(although the Robinson et al. reference below cross references the
Toxicologist abstract):

> Robinson, M.K., Stotts, J., Danneman, P.J., Nusair, J.L. and Bay,
> P.H.S. (1989). A risk assessment process for allergic contact
> sensitization. Fd. Chem. Toxic. 27:479-489.

In reaching the conclusion that DDBSA is a weak sensitizer from this
information, however, EPA's reviewing toxicologist has overlooked the
paragraph that follows the information from the guinea pig studies. This
paragraph is reproduced below:

> *Human sensitization testing was conducted with LAS alone (on 2294
> subjects) and LAS in various product formulations (on 17,887 subjects)
> at LAS concentrations ranging from 0.001 to 0.113% (Fig. 4). The HRIP
> tests of LAS solutions covered 17 commercial batches of LAS, and over
> 100 commercial batches of LAS were used in the products tested in the
> HRIPTs. None of the test subjects (more than 20,000) showed evidence
> of a skin sensitization reaction (Nusair et al., 1988). As a result,
> provocative use testing was unnecessary. Extended product use testing
> showed no evidence of sensitization or any other skin reactions (Fig.
> 4). Of 79 consumers with skin problems alleged to be associated with
> the use of LAS-containing products, and who were patch tested with
> solutions of the LAS-containing products, none gave a positive patch
> test result.*

While the concentrations tested in the human studies are lower than
those in the guinea pig studies, the concentrations in the human tests
are representative of the potential exposure concentrations in the
scenarios used in EPA's risk assessments. Most importantly, it is
standard practice within EPA to utilize human patch test data in
reaching conclusions on skin sensitization potential when there is
disparity between the human and animal data. Further, the sheer volume
of human tests must be considered highly significant in showing that
these types of surfactants are not skin sensitizers. Based on
information previously provided (Memo from J. Van Miller to H. Garvey of
April 11, 2006), the cited 'sensitization in the monkey inhalation
study' is readily ascribed to the known effects of the enzymes in the
dust used in the study. As stated in the comment on the Preliminary Risk
Assessment above, the overwhelming evidence from the available animal
and human studies is that LAS (and DDBSA) are not skin sensitizers. The
conclusion reached in the RED review, therefore, should be changed.

2\. The following response was made to our Errors Only Comment regarding
the fact that the NOAEC from the inhalation study with monkeys (MRID
43498403) should be considered a conservative estimate:

> *However, it should be noted that most uses of this detergent are in
> liquid form. It is a common misconception that the small particle size
> used in an animal/rodent study (MMAD of 1-3 um in acute studies, 1-4
> um in multiple exposure studies) has no relevance to the large
> particle size that comes from medium to coarse powdered material, or a
> liquid-powder mix during use. Detergents are typically mixed with
> large quantities of water before use. When the aqueous mix is used,
> droplets rapidly shrink as they fall due to water evaporation. The
> degree of shrinkage depends on temperature, relative humidity,
> particle size, and the length of time that the droplets are suspended
> in the air. Since humans are capable of inhaling particles \>100 um,
> it is reasonable to expect a significant portion of these particles to
> be inhaled. While most large particles are captured in the nose, some
> are capable of reaching the lungs. Large particles have the potential
> to do considerable local damage if they are respirable because of the
> volume of material they contain. Furthermore, the Agency inhalation
> guidelines recommend testing in rats. Rats have tortuous nasal
> turbinates that are extremely efficient at removing particles from
> inhaled air, hence most particles larger than 1-2 um are captured in
> the rodent nose.  *
>
> Response: The reviewer's comments regarding "common misconception" of
> inhalable particle size and the statement that humans can inhale
> particles \>100 µm are confusing. It is a well established
> toxicological principle that particles of greater than 10 µm are not
> inhaled at any significant concentration in the lungs of humans (see
> for example Figure 5 in the paper by Raabe -- previously provided).
> Indeed, EPA's own documents on determination of RfD, rely on this
> principle (see for example Figure 3.3, page 3-10 -- previously
> provided). This figure shows that with mouth breathing, pulmonary
> deposition fraction drops to 0 (zero) with aerosols having an
> aerodynamic diameter of approximately 10 µm. Also, Figure 3.3
> demonstrates that aerosols \>20 µm can not reach the tracheobronchial
> or pulmonary regions because they deposit in the mouth or larynx
> before reaching the lungs. Aerosols \>100 µm have a sedimentation
> velocity (\>25 cm/sec) too great to stay airborne long enough to be
> available for inhalation by humans. Although our original comment was
> simply made to ensure it was clear that the dust in the monkey study
> was produced to enhance the total inhaled dose (thus making the
> exposure highly conservative), and EPA has subsequently removed its
> reference to the estimates being "underestimates of risk", it is very
> important that the Agency carefully reviews its procedures for risk
> assessment when using non-standard and/or reinterpreted basic and
> long-accepted toxicologic principles. Further, it is not clear why the
> reviewer refers to "rat" nasal turbinates when the study was conducted
> in monkeys. And lastly, if there is a foundation for the discussion of
> liquid detergent drop sizes shrinking, it should be clearly provided
> if it impacts the risk assessment. In reality, exposure to aerosols of
> DDBSA would not be a significant concern, the surfactancy of the DDBSA
> would limit volatility, and drop size of any potential aerosol would
> be large and would not be suspended for extended periods of time. 
> This is supported by the data on particle sizes from aerosol spray
> products included in the LAS SIAR (pp. 19-20). The study data reported
> could be considered a worst case for generation of respirable
> particles and yet the results indicate the fraction under 10 microns
> is less than 0.1% of the total volume sprayed and the maximum
> concentration in air is only 0.13 to 0.72 mg/m3.

3\. The molecular weight of 298.44 represents the mass of C16 moiety and
not C10 moiety (16 x 12 + 1 x 26 + 16 x 3 + 1 x 32) = C16H26O3S =
298.44.

> Response: The chemical formula for the C16 moiety of DDBSA is
> C~22~H~38~O~3~S with MW=382.6 \[Note that the formula in the Agency's
> comment excludes the benzene ring\]. **However, based on recent
> information received from the LAS Producers, the mean chain length
> distribution for DDBSA is approximately 11.7 and therefore, the Agency
> may wish to use the C12 moiety as the most representative:
> C~18~H~30~O~3~S of MW = 326.5.**

[^1]: Modified from http://www.dpandp-sale.demon.co.uk/cleaning.html