Comments on

TSCA Work Plan Chemical Problem Formulation and Initial Assessment:

Chlorinated Phosphate Ester Cluster Flame Retardants

EPA Document # 740-R1-5001, August 2015

EPA–HQ–OPPT–OPPT-2015-0068; FRL–9929–31

80 Federal Register 49997-49999 (Tuesday, August 18, 2015)

Submitted Nov 18, 2015

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Summary

Environmental Defense Fund (EDF) strongly supports EPA’s efforts to assess chemicals through the TSCA

Work Plan Chemical Program, including these clusters of flame retardant chemicals. We appreciate the

opportunity to comment on these three clusters’ Problem Formulation and Initial Assessment

documents. Our comments address the following points:

The proposed scopes of these three Problem Formulation and Initial Assessment documents will

almost certainly lead to risk assessments that significantly underestimate risks posed by these

chemicals.

Inadequate or overly conflated justifications are provided for many key decisions and there are

inconsistencies in the documents’ content, transparency, and format.

Specific EDF recommendations are offered on scope, data availability/data gaps, presentation

and future action.

Food as a route of exposure due to releases from production, processing, use or disposal of a chemical or products or materials containing a chemical that falls under TSCA should be included.

EPA should consider flame retardant exposures via municipal wastewater and acknowledge consumer product use as a source in municipal wastewater treatment facility influent.

The purpose of clustering chemicals should be made more transparent.

EPA should establish and make publicly available a risk assessment development and

completion schedule.

We fully recognize the constraints under which the Agency is operating. In light of this, we encourage

EPA to take a two-fold approach:

1) Move forward swiftly with completing risk assessments in (relatively) data-rich areas and with

regulatory actions to address identified risks.

2) Fully acknowledge the limited scope of and exclusions from these assessments; actively take

steps to fill data gaps in data-poor areas; and revisit and expand the scope of assessments as

new data become available.

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Table of Contents

Summary ....................................................................................................................................................... 1

Table of Contents .......................................................................................................................................... 2

Introduction .................................................................................................................................................. 3

Response to Request for Public Comment ................................................................................................... 4

I. The proposed scopes of these three Problem Formulation and Initial Assessment documents

will almost certainly lead to risk assessments that significantly underestimate risk. .......................... 4

II. Inadequate or overly conflated justifications are provided for many key decisions and there

are inconsistencies in the documents’ content, transparency, and format. ........................................ 8

a. Inadequate justification for scoping decisions. ........................................................................ 8

b. Inappropriate conflation of justifications based on low risk and limited data availability. .... 10

c. Issues with presentation clarity and consistency in analysis and data presentation across the

documents. ..................................................................................................................................... 11

III. Specific EDF recommendations on scope, data availability/data gaps, presentation and

future action: ...................................................................................................................................... 12

a. A systematic approach to selecting exposure pathways should be employed. ..................... 12

b. Clearly describe the literature review process. ...................................................................... 13

c. Clearly present results from other government reviews of the chemicals. ........................... 14

d. Critical information on assessment scope should be systematically presented. ................... 15

e. Improve data presentation and format consistency .............................................................. 15

f. Actions to be taken to fill major data gaps. ............................................................................ 17

g. These risk assessments should be viewed as an ongoing process. ........................................ 18

IV. Qualitative assessment should be included where quantitative assessment is not possible. 18

V. Food as a route of exposure due to releases from production, processing, use or disposal of a

chemical or products or materials containing a chemical that falls under TSCA should be included.

19

VI. EPA should consider flame retardant exposures via municipal wastewater and acknowledge

consumer product use as a source in municipal wastewater treatment facility influent. ................. 21

VII. The purpose of clustering chemicals should be made more transparent. ............................. 23

VIII. EPA should establish and make publicly available a risk assessment development and

completion schedule. .......................................................................................................................... 23

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Introduction

Environmental Defense Fund (EDF) strongly supports EPA’s current efforts to assess the risks of

priority chemicals through the TSCA Work Plan Chemical Program. We appreciate the opportunity to

comment on the Problem Formulation and Initial Assessment documents for the Chlorinated Phosphate

Ester Cluster Flame Retardants (“CPE”), Cyclic Aliphatic Bromides Cluster Flame Retardants (“HBCD”),

and Tetrabromobisphenol A and Related Chemicals Cluster Flame Retardants (“TBBPA”).

Due to data gaps, inadequate authority to address those gaps, and resource constraints, the

scopes of these three Problem Formulation and Initial Assessment documents are limited. The narrow

scope will undoubtedly lead to risk assessments that significantly underestimate the risks posed by

these chemicals, due to exclusions of many uses, potentially relevant pathways and routes of exposure,

hazard endpoints, and certain populations.

In carrying out the TSCA Work Plan Chemical Program, we encourage the Agency to thoughtfully

balance the dual importance of using robust science and comprehensive assessment methodologies on

the one hand, and providing for timely decision-making on the other. As stated in the National Academy

of Sciences’ (NAS) 2009 report Science and Decisions:1 “The design of a risk-assessment process should

balance the pursuit of individual attributes of technical quality in the assessment and the competing

attribute of timeliness of input into decision-making” (p. 72) While it is critical that, over time, the

Agency addresses major data gaps to fully understand the risks associated with all TSCA uses of a

chemical, or group of chemicals, this process should in no way hinder the forward movement of risk

assessments for those uses and exposures for which adequate information exists, and prompt

management and reduction of identified risks.

We fully recognize the data constraints under which the Agency is operating. In light of this, we

encourage EPA to take a two-fold approach:

1) Move forward swiftly with completing risk assessments in (relatively) data-rich areas and with

regulatory actions to address identified risks.

1 NRC (National Research Council), 2009. “Science and Decisions: Advancing Risk Assessment (NAS Final Report).”

Available at: http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=202175.

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2) Fully acknowledge the limited scope of and exclusions from these assessments; actively take

steps to fill data gaps in data-poor areas; and revisit and expand the scope of assessments as

new data become available.

Response to Request for Public Comment

I. The proposed scopes of these three Problem Formulation and Initial Assessment documents will almost certainly lead to risk assessments that significantly underestimate risk.

The risk assessments resulting from these Problem Formulation and Initial Assessment

documents will very likely underestimate the risks posed by the associated chemicals, due to the

exclusion of many uses, sources and routes of exposure, hazard endpoints, and certain exposed

populations. The Agency needs to explicitly acknowledge these limitations in the risk assessments.

Specific examples of factors leading to underestimates of risk are provided below.

Chlorinated Phosphate Ester (CPE) Cluster:

The Agency intends to limit its assessment to exposures via the oral route, excluding dermal and

inhalation routes of exposure due to data gaps. In the CPE Problem Formulation and Initial Assessment

document, EPA explains:

EPA/OPPT has identified the absence of inhalation and dermal route-specific toxicity data as a critical data

need because EPA/OPPT expects that these may be important exposure pathways that cannot be

assessed due to data gaps. Inhalation and/or dermal exposures are possible in a number of occupational

and consumer settings. The absence of sufficient route-specific toxicity data effectively prohibits the

assessment of risks to workers in the occupational setting and to consumers in a residential setting. This

data gap may result in the underestimation of aggregate risks associated with exposure to the CPE FR

cluster chemicals. (p. 39)

EPA’s rationale for excluding these routes of exposure (i.e., lack of route-specific toxicity data) is difficult

to understand,2 given that a 2009 EU risk assessment not only included inhalation and dermal exposure

to TCEP, a cluster member, but identified significant risks to workers via these routes. Furthermore,

2 For industrial worker scenarios, we understand that there is also insufficient U.S. exposure monitoring data.

However, EPA does not reference this data gap as the reason for which worker exposure will be excluded. EPA needs to provide a clearer rationale.

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industrial and non-industrial workers will be excluded entirely from the assessment, as oral exposures

(e.g., incidental ingestion of inhaled dust) will also not be assessed for such populations.3

As a result of EPA omitting these routes of exposure in its assessment, the associated risks to

industrial and non-industrial worker populations as well as to consumers are likely to be dramatically

underestimated in the risk assessments.

Furthermore, it appears that the Agency intends to restrict its assessment of acute exposures to

developmental toxicity via material exposure (see Table 2-10, “Relevant Endpoints for Human

Receptors” and Figure 2-3, “Conceptual Model for Human Receptors”). While EPA indicates that chronic

exposures are of greater concern for these cluster chemicals (see p. 39), its exclusion of acute toxicity

scenarios will underestimate risk. It should also be noted that EPA has assigned a “High” acute toxicity

designation for the cluster chemical TCEP in the Design for the Environment (DfE) Flexible Polyurethane

Foam Alternatives Assessment (finalized in Aug. 2015).4

Cyclic Aliphatic Bromides Cluster (HBCD):

The Agency intends to limit its assessment of HBCD to oral exposures, excluding dermal and

inhalation routes due to data gaps. These exclusions will likely underestimate risk for both the general

population and consumers. For workers, the underestimation may be even greater, as EPA intends to

assess incidental ingestion of inhaled particles and dust as the only route of oral HBCD exposure. In the

worker population, exposure via inhalation of airborne dust and dermal absorption may be comparable

to or even greater than incidental ingestion. As noted by the European Commission (described in the

DfE Alternatives Assessment on HBCD): 5

The primary occupational exposure to HBCD is through inhaling airborne dust (European Commission

2008). Ingestion may occur as a result of inhaling dust but is not expected to be a relevant route of

occupational exposure (European Commission 2008). Workers may also be exposed through dermal

deposition of airborne dust or direct handling of the chemical or products during chemical and product

manufacturing and during construction (European Commission 2008). (p. 2-11)

3 EU, 2009. “European Union Risk Assessment Report: TCEP.” Available at:

http://echa.europa.eu/documents/10162/6434698/orats_final_rar_tris2-chloroethylphosphate_en.pdf 4 US EPA, 2015. “Flame Retardants Used in Flexible Polyurethane Foam: An Alternative’s Assessment Update.”

Available at: http://www2.epa.gov/sites/production/files/2015-08/documents/ffr_final.pdf. 5 US EPA, 2014. “Flame Retardant Alternatives for Hexabromocyclododecane (HBCD), Final Report.” Available at:

http://www2.epa.gov/sites/production/files/2014-06/documents/hbcd_report.pdf

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Furthermore, EPA is excluding end-of-life (e.g., disposal) pathways from its assessment, which may

entail exposures that are be particularly relevant for workers (e.g., exposure during demolition of

structures containing insulation foam).

EPA also intends to exclude carcinogenicity and developmental neurotoxicity – both potentially

relevant endpoints – from its assessment. The HBCD document acknowledges that “no adequate

carcinogenicity studies are available” (p. 27). EPA’s DfE 2014 Alternatives Assessment for HBCD predicts

medium hazard potential for carcinogenicity based on predictive models/professional judgement.6 The

HBCD assessment may underestimate overall risk from HBCD exposure due to the exclusion of potential

cancer risk. (See further discussion on developmental neurotoxicity in section IX of our Cyclic Aliphatic

Bromides Cluster comments.7)

Tetrabromobisphenol A (TBBPA) and Related Chemicals Cluster:

The Agency intends to limit the assessment of this cluster to a single member, TBBPA, and to

include only limited oral exposure routes (e.g., drinking water will be excluded). Although not explicitly

stated,8 it appears that the inhalation and dermal routes of exposure will be excluded entirely from

further assessment due to a combination of what EPA deems low concern and lack of data. For the

worker population in particular, this exclusion may significantly underestimate risk, because, as with the

HBCD assessment, only incidental ingestion of inhaled dust will be assessed.

TBBPA is most commonly used in electrical or electronic products, such as printed circuit boards.

EPA’s 2015 DfE report, Flame Retardants in Printed Circuit Boards,9 explains that exposure potential

from TBBPA-containing electronic waste (e-waste) is a major data gap:

[T]he potential environmental and health impacts of exported electronic waste (e-waste) are not fully

understood. A large percentage of e-waste is sent to landfills or recycled through smelting to recover

metals. An unknown portion of the waste is recycled under unregulated conditions in certain developing

countries, and the health implications of such practices are of concern. (p. 1-1)

6 Id.

7 Submitted to the following docket on www.regulations.gov: EPA-HQ-2015-0081-0001.

8 See section II.a. for further discussion.

9 US EPA, 2015. “Flame Retardants in Printed Circuit Boards: Final Report.” Available at:

http://www2.epa.gov/sites/production/files/2015-08/documents/pcb_final_report.pdf

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In its current review, EPA has decided to exclude environmental and human health impacts from

recycling e-waste due to data limitations, and from e-waste disposal due to “required controls, limited

data or low concerns” (p. 10).10 These exclusions may result in a significant underestimation of risk. An

estimated 20-25 million tons of e-waste are generated globally each year11 – and by EPA’s own

estimates, generation of e-waste is increasing by 5-10% every year.12 TBBPA is a persistent,

bioaccumulative, and toxic (PBT) chemical13 that is showing up in e-waste around the globe.14,15,16 By

excluding product recycling and disposal pathways from its assessment, EPA is likely to exclude major

sources of exposure and hence risks – such as exposure to recycling workers and lifecycle impacts from

domestically processed as well as exported e-waste.

In addition to excluding the inhalation and dermal routes of exposure in all three of these

assessments, EPA also plans to exclude potentially relevant pathways of exposure via the oral route

(e.g., see discussion of exposure via food sources in section V and via wastewater in section VI).

Exclusion of these routes of exposure is likely to result in underestimations of risk in the risk

assessments.

10

See section II.b for discussion on our concerns on EPA’s failure here to differentiate between low risk concern and limited data availability. 11

Robinson, B.H. (2009). “E-waste: An assessment of global production and environmental impacts.” Science of the Total Environment, Vol 408(2): 183-191. Available at: http://www.sciencedirect.com/science/article/pii/S0048969709009073. 12

US EPA, as cited in Pramila, S., M.H. F., and Bhawana, P. (2012). “E-waste – A Challenge for Tomorrow.” Research Journal of Recent Sciences, Vol. 1(3), 86-93. Available at: http://www.globalewastemanagement.com/contents/article/14-ISCA-RJRS-2012-041-Done.pdf. 13

TBBPA is one of 20 PBT chemicals/chemical compound categories covered by EPA’s TRI program: http://www2.epa.gov/toxics-release-inventory-tri-program/persistent-bioaccumulative-toxic-pbt-chemicals-covered-tri. 14

Pramila, S., Fulekar, M. H., Bhawana, P. (2012). “E-Waste – A Challenge for Tomorrow.” Research Journal of Recent Sciences, Vol 1(3), 86-93. Available at: http://www.globalewastemanagement.com/contents/article/14-ISCA-RJRS-2012-041-Done.pdf. 15

Ni, H-G., Zeng, H., Tao, S., et al. (2010). “Environmental and human exposure to persistent halogenated compounds derived from e-waste in China.” Environmental Toxicology and Chemistry, Vol 29(6), 1237-1247. DOI: 10.1002/etc.160. Available at: http://onlinelibrary.wiley.com/doi/10.1002/etc.160/full.

16 Lovegrove, S. (2008). “Export of Electronics Equipment Waste.” International Journal of Occupational and

Environmental Health, Vol. 14(1), 1-10. DOI: Available at: http://www.maneyonline.com/doi/abs/10.1179/oeh.2008.14.1.1.

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For all three assessments, EPA intends to aggregate oral exposures for consumers/general

population, which will provide more realistic risk estimates for oral exposures. However, it appears that

the Agency does not intend to aggregate oral exposures for workers in the two assessments addressing

this population (HBCD and TBBPA) – effectively ignoring background exposures in the population likely

at greatest risk. It is also noteworthy that EPA plans to drop three TBBPA cluster chemicals and one

HBCD cluster chemical completely from further review, which will also result in underestimated total

risk for each of these clusters.

In sum, given these limited scopes and omissions, it is essential that the Agency: 1) recognize

and clearly acknowledge expected underestimations of risk in the risk assessments and in any regulatory

actions following completion of the risk assessments, 2) identify data gaps in those assessments and

initiate actions to fill them, and 3) revisit its risk assessments of these chemicals as additional

information is developed; such assessments should be seen as an ongoing process (discussed further

below).

II. Inadequate or overly conflated justifications are provided for many key decisions and there are inconsistencies in the documents’ content, transparency, and format.

In these three Problem Formulation and Initial Assessment documents, EPA often provides

inadequate justification for decisions that will directly affect the scopes of the assessments. In addition,

there are significant inconsistencies across the three documents in content, presentation/transparency

and general format that should be remedied in the risk assessments, and resolved in advance of

developing additional such Problem Formulation and Initial Assessment documents for other TSCA Work

Plan chemicals going forward.

a. Inadequate justification for scoping decisions.

The Agency often makes assertions regarding uses and sources of exposure without backing

them up, i.e., without providing a robust rationale, supporting data, or reference citations to justify the

exclusion of a use, exposure scenario, or source. For example, Section 2.6.3 (“Pathways Excluded from

Further Assessment”) of the CPE document provides absolutely no rationale or supporting evidence for

EPA’s assertions that: 1) manufacturing and processing resulting in exposures to adjacent communities,

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2) manufacture of printed circuit boards, 3) formulation of paints and coatings, and 4) use of TDCPP in

fabric, textiles and leather products are “not expected to result in significant releases to the

environment and therefore will not be assessed” (p. 7). (Indeed, for the first three, there is no

justification provided anywhere in the document.) It should be noted that there is considerable use of

CPEs in printed circuit boards, paints and coatings, and fabric textiles and leather (TDCPP), as these uses

were reported in the 2012 CDR (Table 2-5, pp. 19-20).17 Additionally, the exclusion of worker

populations (as illustrated in the Conceptual Model, p. 30), is never acknowledged or justified in the

Executive Summary or section 2.6.3. While an explanation is provided as to why inhalation of vapor and

dermal exposures cannot be assessed (i.e., no route-specific toxicity data), no explanation is provided as

to why other routes of exposures will not be assessed in workers – such as incidental ingestion of

inhaled dust.18

These omissions contrast greatly with Section 2.6.3 of the TBBPA document, which is much

more comprehensive. For example, the TBBPA document explains that EPA conducted a preliminary

exercise/calculation for TBBPA exposures of people in the vicinity of wastewater treatment plants

(WWTPs), and excluded this pathway based partially on an estimated low risk.

While the TBBPA document more effectively presents the Agency’s decision-making processes

for excluding pathways of exposure, it provides little to no detail on the basis for the Agency’s decision

to exclude the dermal and inhalation routes of exposure. There is no mention of the exclusion of these

routes of exposure in the Executive Summary (i.e., in the section “EPA/OPPT will not specifically assess

the following risks,” p. 10), and the only statement directly addressing the exclusion of these routes of

exposure is in a footnote to Table 2-7, p. 39. While there are scattered statements implying the

Agency’s viewpoint that these routes present low risk (e.g., “TBBPA is likely to be emitted as dust rather

than vapor based on its low vapor pressure” [p. 27] and “Dermal exposure is also possible but available

17

This is an example of likely underestimation of risk, discussed previously in section II. 18

While we recognize that EPA has indicated that there are no U.S. exposure monitoring data available, a similar strategy could be taken for CPE as will be taken in the HCBD assessment (see p. 31 of HBCD document: “EPA/OPPT plans to evaluate the applicability of data for worker exposure to HBCD through manufacturing and processing for the manufacture of EPS and XPS reported in EC (2008) and NICNAS (2012) to US occupational exposure scenarios. If the available data are not applicable, [sic] develop estimates of occupational exposures based on modeling and assumptions (e.g. approaches used in the new chemicals program).”).

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data indicates that absorption is limited” [p. 30]),19 no robust rationale describing the Agency’s decision

to drop these routes of exposure is provided in a single place in the document.

b. Inappropriate conflation of justifications based on low risk and limited data availability.

The Agency frequently conflates or fails to distinguish between rationales based on expected

low exposure and/or low toxicity concern versus data gaps. Clearly differentiating between these two

explanations for any exclusions is essential: Just because data are limited does not mean that no or low

risk can be concluded. Blurring these lines implies lower concern/risk than may actually exist. For

example:

Tetrabromobisphenol A (TBBPA) and Related Chemicals Cluster:

The TBBPA document provides the following rationale for excluding three of the four cluster

members from further analysis:

Some limited information is available for the cluster members other than TBBPA. However, EPA/OPPT

concluded that no quantitative risk assessment is needed for these other cluster members for one or

more of the following reasons: limited information, inability to use the more robust data for TBBPA to

read across to other cluster members, low toxicity or likely low risk concerns. (p. 10, emphasis added.)

This rationale is rendered wholly opaque by lumping together reasons based on low expected concern

and limited data. While “is needed” may be the appropriate verb for the last two reasons (i.e., low

toxicity or likely low risk concerns), the verb “is possible” should be used to accurately reflect the first

two reasons (i.e., limited information, inability to use the more robust data for TBBPA to read across to

other cluster members). A much clearer discussion that specifies which rationales apply to which cluster

members, uses, exposures and endpoints is needed. As currently written, the Agency is inappropriately

claiming that further assessment is somehow unwarranted because of insufficient data.

Cyclic Aliphatic Bromides Cluster (HBCD):

In delineating excluded exposure scenarios, the document states: “Several scenarios were

identified where exposure to HBCD is expected to be low or unknown and further analysis is not

19

We presume, though it is never stated, that the Agency’s decision to exclude the dermal and inhalation routes of

exposure is based on low exposure potential, provided EPA’s conclusion that “[o]nly few inhalation and dermal studies are available and therefore, there is uncertainty as to effects specifically from these routes” (p. 48).

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recommended by EPA/OPPT under TSCA” (p. 8, emphasis added). This statement begs the question, on

what basis is exposure “expected” to be low? And if exposure is unknown, how can any risk conclusion

be drawn and why would no further analysis be called for? An unknown exposure does not equate to

no or low exposure. Here again, a much clearer discussion that specifies which rationales apply to which

cluster members, uses, exposures and endpoints is needed.

Chlorinated Phosphate Ester (CPE) Cluster:

In contrast to the TBBPA and HBCD documents, the CPE document differentiates between

scenarios excluded on the basis of low exposure potential (“EPA/OPPT has determined that several uses

are not expected to result in significant releases to the environment and therefore will not be assessed,”

p. 7)20 versus insufficient data (“EPA/OPPT has determined that a number of scenarios lack sufficient

data to quantify risks and therefore will not be assessed at this time,” p. 7). This type of clear distinction

between low risk potential and insufficient data should be utilized moving forward.

c. Issues with presentation clarity and consistency in analysis and data presentation across

the documents.

Critical information is often buried in the documents or its presentation is unclear when

included in the upfront summaries. Much of the data is buried in the Appendices, without consistent

cross-references to it earlier in the document. The HBCD document, in particular, does not even

mention the health endpoints that will be considered in the risk assessment in the Executive Summary.

Other critical information or decisions are sometimes included in the body of the documents, but

without appropriate references or cross-references to where the detail is provided. For example, in the

TBBPA document, EPA asserts that for workers, “[d]ermal exposure is also possible but available data

indicates that absorption is limited” (pg. 30). The support for this statement – which is presumably used

as justification to exclude the dermal route of exposure – is not provided until Appendix G, p. 109, and

no cross-reference to it is provided earlier.

Inconsistencies in format, content, and location of tables across the three documents abound.

Examples include the “Exposure Scenarios Considered” tables (Table 2-2 for HBCD; Table 2-7 for TBBPA;

Tables 2-8 and 2-9 for CPE) and the data availability tables (Table 2-5 and Appendix A-7 for TBBPA; 20

However, this statement is an example of an assertion made without adequate justification, as discussed above in section II.a.

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Appendix A for CPE; none for HBCD). See section III.e for further discussion. Similarly, the content in the

Appendix differs across the three documents and is not presented in a consistent order. These

inconsistencies in format and structure make it difficult for the reader to consider the three documents

together.

III. Specific EDF recommendations on scope, data availability/data gaps, presentation and future action:

We fully understand the limitations under which the Agency is operating, given data gaps,

limited authority to address those gaps, and resource constraints. We encourage EPA to move forward

swiftly with risk assessments in (relatively) data-rich areas and with targeted regulatory actions where

potential risks have been identified, so that those risks can be reduced.

We also recommend that the Agency make a number of improvements in future Problem

Formulation and Initial Assessment documents as well as in the risk assessments for the present

chemical clusters. These are needed to increase transparency and clarity regarding: the limited scopes

of the assessments; data availability/gaps; the Agency’s decision-making process as to what is

included/excluded and why; and needed actions and plans to fill major data gaps.

a. A systematic approach to selecting exposure pathways should be employed.

Future Problem Formulation and Initial Assessment documents should develop and provide a

description of preliminary risk calculations used to identify and prioritize among uses, sources and

exposure pathways, as was done in the TBBPA assessment. The TBBPA document appears to have

followed and presents a relatively systematic approach to identifying which exposure scenarios are to be

evaluated further, and why: EPA calculated preliminary high-end exposure estimates from existing risk

assessments and recent data and calculated a provisional health toxicity value using a carcinogenic

bioassay for uterine tumors. Scenarios for young children were also compared to the NOAEL from a

developmental toxicity study (see p. 18).

Employing this approach to scoping and presentation would provide more credibility and

transparency to EPA’s decisions on including/excluding uses, exposure pathways, endpoints, etc. If a

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similar approach was employed for the CPE and HBCD clusters, it was not described in the documents.

In the future, a more systematic approach to determining the scope of assessments should be

consistently employed and presented in these Problem Formulation and Initial Assessment documents.

b. Clearly describe the literature review process.

These documents would benefit from a clear description of the approach EPA used or intends

to use to search the broader literature. While short literature reviews on the human health and

ecological hazards as well as exposure data are included, it is unclear how the Agency conducted its

literature search, how the studies it included were selected, and whether some studies were excluded

and, if so, why.

For example, the documents include limited mention of human studies, aside from some

biomonitoring and exposure monitoring data. From our own cursory literature search, it seems that this

may be due to a dearth of epidemiology literature assessing exposure to these compounds.21 EPA

should describe in these documents the extent of availability – or lack thereof – of human studies

(including epidemiological studies).

While we recognize that the Agency may not have fully conducted their literature search at this

early stage in the assessment process, we recommend that the risk assessments fully describe the

literature on which they are based and that future Problem Formulation and Initial Assessment

documents fully describe the literature search approach the Agency intends to take – including

identification and evaluation of scientific research studies, government documents, and grey literature

(e.g., REACH dossiers; unpublished industry regulatory studies).

21

For example, the Health and Environment Network (HENVINET) consortium identified epidemiological and toxicological studies in humans as a priority area for further HBCD research. For detail, see: Ravnum, S., Zimmer, K.E., Keune, H., et al. (2012). “Policy relevant Results from an Expert Elicitation on the Human Health Risks of Decabromodiphenyl ether (decaBDE) and Hexabromocyclododecane (HBCD).” Environmental Health, doi:10.1186/1476-069X-11-S1-S7.

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c. Clearly present results from other government reviews of the chemicals.

In addition to clearly presenting the literature review process, future documents should clearly

identify which chemicals have had any prior government reviews and present the outcome of those

reviews. The current documents do provide a fairly well-structured regulatory and assessment history by

U.S. states and other countries (e.g., EU, Canada), but earlier reviews conducted by the Agency are

inconsistently presented and often glossed over. For example, only a single sentence in the HBCD

document mentions that the Agency conducted a DfE Alternatives Assessment on HBCD; the results are

not discussed.

We recommend that relevant Agency reviews, including but not limited to any Integrated Risk

Information System (IRIS) assessment, DfE alternatives assessment, and Provisional Peer-Reviewed

Toxicity Values (PPRTVs), should be systematically included along with the outcome of those reviews in

future Problem Formulation and Initial Assessment documents. We recommend developing an

Appendix table with relevant Agency reviews, completion date, and the outcome of the review. Table -

Apx A-1 of the HBCD document, which provides a comprehensive reference list of relevant EPA

regulation and assessments, is a good start; future Problem Formulation and Initial Assessment

documents could build upon this structure to also include regulatory status and outcomes of each

assessment (as is provided in bullet point form in Appendix B-1 of the CPE document).

It is particularly relevant to note earlier TSCA reviews of the chemicals, such as through the New

Chemicals Program. These documents should explicitly state whether any of the chemicals in the cluster

went through review under the New Chemicals Program and, if so, any data or analysis conducted on

such chemicals should be summarized and citations or means of access should be provided. The CPE

document appropriately explains: “TCEP, TDCPP and TCPP are existing chemicals on the TSCA Inventory

and therefore were not subject to EPA’s new chemicals review process and were grandfathered in with

the passage of the Toxic Substances Control Act of 1976” (p. 13). However, neither the TBBPA

document nor the HBCD document mention whether or not any of the chemicals in the cluster went

through New Chemicals Program review. From our research, it appears that none of the chemicals in

these two clusters did so;22 but readers should not have to search for such information.

22

It is our understanding that three of the chemicals in the brominated phthalates cluster (TBB, CASRN: 183658-27-7; Confidential A, PMN: P-96-0965; and Confidential B, PMN: P-04-0404) went through the new chemicals

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d. Critical information on assessment scope should be systematically presented.

In future Problem Formulation and Initial Assessment documents, EPA should consistently and

systematically include the following information in a single place (e.g., a table) up front in the

documents, and provide cross-references to the relevant sections in the documents where detail is

provided:

1. What uses and exposure scenarios and routes the Agency has considered

2. What uses and exposure scenarios and routes the Agency will include/will not include in

the assessment

3. Clear rationales and documentation for why any excluded use or exposure scenario or

route will not be assessed (e.g., gap in exposure/toxicity data, high confidence in

conclusion of low risk), specified for and differentiated among each

use/exposure/route/endpoint

4. Non-cancer and cancer endpoints to be assessed (or excluded) for each route of

exposure

5. Gaps in use, toxicity or exposure data

6. Plan/next steps to address major data gaps (see subsection f. below).

e. Improve data presentation and format consistency

Future Problem Formulation and Initial Assessment documents should have clearer data

presentation and format consistency. Specific recommendations include:

Executive Summary

o Include a clear summary of the uses, exposure scenarios, and health endpoints

included/excluded, as well as key data gaps and next steps to address them (this could be

done by means of the table recommended in subsection d. above).

o Each conclusion or scoping decision presented in the Executive Summary should include a

cross-reference to where in the report support for the statement is provided.

program. The Brominated Phthalates Data Needs Assessment does not indicate this, however, nor does it indicate the outcome of the review or the data or analysis developed on those chemicals. See Receipt of PMN for TBB (P-95-1128): http://www.gpo.gov/fdsys/pkg/FR-1995-08-11/pdf/95-19903.pdf and Notice of Commencement: http://www.gpo.gov/fdsys/pkg/FR-1997-08-08/pdf/97-20984.pdf.

16

Body/Appendix:

o References should be consistently provided, especially when explaining why an exposure

scenario has been excluded from further assessment.

o Content and format of data tables and figures should be consistent across Problem

Formulation and Initial Assessment documents. Examples of inconsistencies include:

Table 2-10, “Relevant Endpoints for Human Receptors,” in the CPE document clearly

presents health endpoints being considered for different populations and exposure

durations. Analogous tables are not provided in the TBBPA and HBCD documents,

however. Future Problem Formulation and Initial Assessment documents should

provide this health effects content in a more standardized manner and format.

Future documents should better incorporate the health endpoints being considered into

the Conceptual Models. In the current format, it is unclear whether or which endpoints

apply to acute, sub-chronic, or chronic exposures and which cluster members will be

assessed for each health endpoint (if relevant).

The “Availability of Exposure Data” tables in the CPE and TBBPA documents provide

clear and effective summary information, and analogous tables should be provided

consistently and in the same location in future Problem Formulation and Initial

Assessment documents. These tables could be improved by providing a third column

that includes available references. Further, the CPE document utilizes a similar format

to present available occupational exposure and release data in an additional table (Table

Apx A-1, p. 55); an analogous table should be included in future Problem Formulation

and Initial Assessment documents.

The “Exposure Scenarios Considered” tables should have consistent structure, format,

and content across different Problem Formulation and Initial Assessment documents.

The data are presented most clearly in the TBBPA table (Table 2-7, pp. 38-39), which

may serve as a model for future documents; however, all routes of exposure considered

should be included (the TBBPA table excludes inhalation and dermal routes of exposure,

aside from a brief mention in footnote c). In addition, separate columns should be

created for “Rationale,” “Limitations,” and “Uncertainties,” as the explanations become

inappropriately conflated and confused when these categories are not clearly

separated. Finally, EPA could use these tables as a starting point to address the scope

summaries that we recommended be included up front (see subsection d).

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f. Actions to be taken to fill major data gaps.

EPA should develop and present a plan to fill major data gaps, specifically by pursuing test rules,

section 8(a) or 8(d) rules, or other data call-ins for the chemicals in these three flame retardant clusters.

Examples of possible regulatory actions that should be considered to address identified data gaps

include:

Chlorinated Phosphate Ester (CPE) Cluster

Section 4 test rule and/or section 8(d) data call-in for inhalation and dermal route-specific

toxicity data (identified in assessment as a critical data need).

Section 4 test rule for exposure monitoring studies of U.S.-based industrial workers.

Section 8(a) reporting rule on the number of individuals exposed in their place of employment

and the duration of exposure.

Cyclic Aliphatic Bromides Cluster (HBCD):

Section 4 test rule and/or section 8(d) data call-in for inhalation and dermal route-specific

toxicity data.

Section 4 test rule for exposure monitoring data for workers in the U.S. (lack of PBPK model

allowing route-to-route extrapolation identified in assessment as critical data gap).

Section 8(a) reporting rule on the number of individuals exposed in their place of employment

and the duration of exposure.

Section 4 test rule and/or section 8(d) data call-in for carcinogenicity studies.

Tetrabromobisphenol A (TBBPA) and Related Chemicals Cluster:

Air/dust exposure monitoring studies at U.S.-based recycling facilities and reporting on the

number of recycling workers exposed. EPA may need to use other authorities to obtain this

information.

U.S. data on recycling and disposal of discarded electronics. EPA may need to use other

authorities to obtain this information.

Section 4 test rule and/or section 8(d) data call-in for dose response data on exposure to TBBPA

and incidence of hepatoblastomas.

The list above provides select examples where regulatory or other action is warranted to obtain

additional information on cluster chemicals selected for further assessment. The many data gaps for the

cluster chemicals dropped from the assessments could also be addressed through regulatory action.

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g. These risk assessments should be viewed as an ongoing process.

Because of the limited scope of these assessments, EPA should neither consider nor imply that

its evaluations of these chemicals is in any way completed upon finalization of the risk assessments. We

recommend that the Agency revisit work plan chemical assessments:

1) Based on new data retrieved through test rules, 8(a) rules, voluntary programs, or other

mechanisms used to close data gaps.

2) Based on evidence of a change in the use patterns of a chemical. It may also be pertinent to

rerun the exposure models periodically (e.g., the pesticide program reruns its exposure

models every time a new tolerance is considered).

As discussed above, the Agency should clearly distinguish between expected low exposure/low

toxicity concerns versus data gaps in future Problem Formulation and Initial Assessment documents and

in the forthcoming risk assessments for the present clusters. Inappropriate conflation of these disparate

rationales may make it more difficult for EPA to justify revisiting excluded scenarios when it has better

data, by inadvertently providing unwarranted arguments to stakeholder groups seeking to limit further

review and risk management of their chemicals by claiming EPA has concluded that further review is

“not needed.”

IV. Qualitative assessment should be included where quantitative assessment is not possible.

In several places in each of these documents, EPA states that a “quantitative assessment”

cannot be conducted – without explaining what the Agency will do in lieu of a quantitative risk

assessment. We suggest that, in cases where potential risks are identified but a quantitative

assessment cannot be conducted due to insufficient data, the Agency should still describe and

qualitatively evaluate risks associated with the exposure scenario in the risk assessment. Further, as

noted earlier, the Agency should identify and initiate action to acquire the data needed for a

quantitative risk assessment, wherever deemed a priority.

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V. Food as a route of exposure due to releases from production, processing, use or disposal of a chemical or products or materials containing a chemical that falls under TSCA should be included.

Two of the documents (CPE and TBBPA) explicitly state that EPA is not considering exposures via

food (other than fish) because this exposure falls under the “purview of other federal agencies” (CPE p.

8; TBBPA p. 10, p. 39, p. 43, p. 46). While excluding food additives (clearly under FDA’s jurisdiction) from

the scope of the assessment may be appropriate, it is wholly inappropriate for EPA to exclude food as a

vector and route of exposure when the contamination of food comes from production, processing, use

or disposal of a chemical or a product or material containing a chemical that falls under TSCA’s

jurisdiction.23

The Agency’s rationale for excluding food sources (i.e., purview of other federal agencies) is

inconsistent with its decision to quantitatively assess exposures via fish consumption for all three flame

retardant clusters. The CPE document indicates that fish consumption will be assessed due to

“stakeholder interest” (p.72). We understand and support the decision to include fish consumption,

given existing models and the concerns regarding flame retardant exposures faced by tribal and

subsistence fishing communities.24,25 However, other food-based exposures resulting from TSCA uses of

these flame retardants may also present considerable risk. For example, a 2010 study that measured

HBCD levels in composite food samples from supermarkets in Dallas, Texas, estimated that HBCD dietary

exposure was considerably higher from meat consumption than fish consumption.26 EPA should use a

systematic approach in determining which food sources will be included in its Work Plan Chemical

assessment process.

23

We do note that EPA gathered and presented data on environmental and wildlife monitoring – including food data – for TBBPA in a supplementary document. (See: http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPPT-2014-0730-0002.) No comparable document is provided for the other two clusters.

24 Liberda, E. N., Wainman, B. C., LeBlanc, A., et al. (2011). “Dietary exposure of PBDEs resulting from a subsistence

diet in three First Nation communities in the James Bay Region of Canada.” Environmental International, Vol 37(3): 631-636. Available at: http://www.sciencedirect.com/science/article/pii/S016041201100002X. 25

Nilsen, E. B., Hapke, W. B., Mcllraith, B., et al. (2015). “Reconnaissance of contaminants in larval Pacific lamprey (Entosphenus tridentatus) tissues and habitats in the Columbia River Basin, Oregon and Washington, USA.” Environmental Pollution, Vol 201: 121-130. Available at: http://www.sciencedirect.com/science/article/pii/S0269749115001256. 26

Schecter, A., Haffner, D., Colacino, J., et al. (2010). “Polybrominated Diphenyl Ethers (PBDEs) and Hexabromocyclodecane (HBCD) in Composite U.S. Food Samples.” Environmental Health Perspective, Vol. 118(3). 357-362. Available at: http://www.ncbi.nlm.nih.gov/pubmed/20064778.

20

It is worth noting that EPA has considered food-based exposures from TSCA uses of chemicals in

the past. For example, polychlorinated biphenyls (PCBs) are persistent chemicals that have entered the

food chain following TSCA-regulated uses of these chemicals. A 1998 National Center for Environmental

Assessment (NCEA) publication on cancer risk from environmental PCBs discussed food-based exposures

of PCBs due to bioaccumulation in food sources, such as fish and beef.27 In the same year, EPA finalized

a rule under TSCA amending its disposal rules for PCBs; the rule describes PCB-containing food sources –

including invertebrates, fish, and mammals – as a relevant route of exposure.28

More generally, food as a route of exposure is routinely addressed in EPA science and policy

documents, such as consumption of rice contaminated with arsenic29 and infant consumption of

contaminated breast milk.30 The Office of Research and Development’s (ORD) Exposure Assessment

Tool Box (“Expobox”)31 includes an entire section on assessing food sources, and describes the lifecycle

impacts of chemicals on the food supply:

Food products (e.g., grains, fruits, vegetables) can become contaminated as a result of ambient pollutants in the air being deposited on plants, adsorbed onto or absorbed by the plants, or dissolved in rainfall or irrigation waters that contact the plants. ¶ Plants growing in contaminated soil can take up the chemicals from soil pore water through their roots, and the chemicals could then be transported into plant tissues. Meat and dairy products from animals used as sources of food can become contaminated if grazing or foraging animals consume contaminated soil, water, or feed crops and bioaccumulate the contaminants in their tissues.

Food as a route of exposure should be included in considering risks across the lifecycle of a

chemical, where appropriate (e.g., industrial pollution/waste>water>soil>crops>people). While food per

27

Cogliano, V.J. (1998). “Assessing the Cancer Risk from Environmental PCBs.” Environmental Health Perspectives, Vol. 106(6): 317-323. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1532993/pdf/envhper00529-0053.pdf. 28

Disposal of Polychlorinated Dibphenyls (PCBS); Final Rule. 63 Federal Register 35383. June 29, 1998. Available at: http://www.ehso.com/pcbmegarule.pdf. 29

Ackerman, A.H., Gallagher, P.A., Parks, A.N., et al. “A Mass Balance Approach to Determine Arsenic Absorption Rates from Contaminated Water by Rice During the Food Preparation Process.” Presented at 2003 European Winter Conference on Plasma Spectrochemistry, Garmisch-Partenkirchen, Germany, January 12-17, 2003. Available at: http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=62520. 30

ICF International. “Improving the Risk Assessment of Persistent, Bioaccumulative, and Toxic (PBT) Chemicals in Breast Milk: Workshop Summary Report.” (2013). U.S. Environmental Protection Agency, Washington, DC. Available at: http://cfpub.epa.gov/ncea/risk/recordisplay.cfm?deid=262210. 31

US EPA, 2015. “Exposure Assessment Tools by Media – Food.” Available at: http://www2.epa.gov/expobox/exposure-assessment-tools-media-food/.

21

se is exempt under TSCA’s regulatory authority,32 this does not preclude EPA from assessing the relevant

risk of chemical contaminants of food arising from environmental sources. In some instances, it may be

appropriate for FDA to implement any needed risk management, but EPA still needs to assess risks

related to consumption of contaminated food from TSCA uses of a chemical. For example, EPA and FDA

have worked together to mitigate exposure to PCBs. EPA banned most commercial uses of PCBs under

TSCA in the late 1970s,33,34 and continues to consider science on food pathways of exposure to PCBs.35,36

FDA, meanwhile, restricts PCB levels in food and paper food-packaging materials.37

VI. EPA should consider flame retardant exposures via municipal wastewater and acknowledge consumer product use as a source in municipal wastewater treatment facility influent.

To the extent possible, EPA should consider and assess presence in wastewater as a pathway of

exposure. Persistent flame retardants can resist wastewater treatment of influent, ending up in the

effluent and sludge, either of which may contaminate drinking water or food sources (e.g., seafood,

crops, farm animals).38,39 As described in the TBBPA document:

Facility waste and final consumer products that contain TBBPA may be sent to WWTPs. Exposure to TBBPA could occur after discharge of effluents from WWTPs to water, where it could remain in surface

32

US EPA, 2015. “Toxic Substances Control Act (TSCA) and Federal Facilities.” Available at: http://www2.epa.gov/expobox/exposure-assessment-tools-media-food. 33

US EPA, 2014. “Polychlorinated Biphenyls (PCBs): Laws and Regulations.” Available at: http://www3.epa.gov/epawaste/hazard/tsd/pcbs/pubs/laws.htm. 34

US EPA, 1986. “Polychlorinated Biphenyls (PCBs): A Bibliography of Regulatory Action and EPA Research.” Available at: http://nepis.epa.gov/Exe/ZyPDF.cgi/90160J00.PDF?Dockey=90160J00.PDF. 35

US Public Health Service, ATSDR, US HHS and US EPA, 2012. “Public Health Implications of Exposure to Polychlorinated Biphenyls (PCBs).” Available at: http://water.epa.gov/scitech/swguidance/fishshellfish/techguidance/pcb99.cfm. 36

US EPA, 2013. “America’s Children and the Environment.” 3rd

Ed. Available at: http://www2.epa.gov/sites/production/files/2015-06/documents/ace3_2013.pdf

37 ATSDR, 2014. “Polychlorinated Biphenyls (PCBs) Toxicity, What Standards and Regulations Exist for PCB

Exposure?” Available at: http://www.atsdr.cdc.gov/csem/csem.asp?csem=30&po=8. 38

Schreder, E.D. and La Guardia M. J. (2012). “Flame Retardant Transfers from U.S. Households (Dust and Laundry Wastewater) to the Aquatic Environment.” Environmental Science and Technology. dx.doi.org/10.1021/es502227h. 39

Dodder, N.G., Maruya, K. A., Ferguson, P. L., et al. (2014). “Occurrence of contaminants of emerging concern in mussels (Mytilus spp.) along the California coast and the influence of land use, storm water discharge, and treated wastewater effluent.” Marine Pollution Bulletin, Vol 81(2): 340-346. Available at: http://www.ncbi.nlm.nih.gov/pubmed/23849955.

22

water or partition to sediments or from generation of sludge that is then applied to agricultural land. (p. 44)

While all three of the documents discuss wastewater as a pathway of exposure, from our

understanding only the CPE cluster will carry this pathway through to a quantitative assessment (and

this is restricted to exposures to aquatic organisms).40,41

We also urge EPA to consider and assess consumer products as a source of flame retardants in

wastewater, in addition to manufacture and processing releases and waste. Use of consumer products

may lead to the discharge of persistent flame retardants in wastewater. For example, Schreder and La

Guardia (2014) measured flame retardants in residential laundry wastewater from 20 residences in

Vancouver and Washington State and found 18 compounds – including the cluster members HBCD,

TCPP, TCEP, and TDCPP.42 Through comparisons of flame retardant levels in influent and effluent from

local WWTPs, the authors predict that laundry wastewater may be the primary source of these flame

retardants in the influent and, for the chlorinated phosphate ester flame retardants – which are not

effectively removed through treatment – into the aquatic environment.

With the exception of the CPE Conceptual Model of Ecological Receptors (Figure 2-2, p. 28),43

none of the conceptual models acknowledge that consumer product use is a pathway for wastewater

contamination – instead focusing exclusively on chemical manufacture, processing, and

disposal/recycling of products. Understanding the full scope of sources of wastewater contamination

will be important in risk management steps and may be relevant for the design of monitoring programs

to identify upstream sources.

Finally, we encourage EPA to consider the potential for levels in wastewater influent (and

subsequent effluent and sludge) as big-picture estimates of aggregate releases of and exposures to

persistent flame retardants. Wastewater may be considered a release/exposure “sink,” capturing

40

See p. 32 of CPE document: “In the risk assessment, EPA/OPPT will assess releases of TCPP and TDCPP to wastewater from manufacturing and processing; and subsequent release to surface water resulting in exposures to aquatic organisms.” 41

As noted in section II.b, the TBBPA document provides an adequate justification for excluding TBBPA exposure to people in the vicinity of WTTPs. 42

Schreder, E.D. and La Guardia M. J. “Flame Retardant Transfers from U.S. Households (Dust and Laundry Wastewater) to the Aquatic Environment.” (2012). Environmental Science and Technology. dx.doi.org/10.1021/es502227h. 43

Note that in CPE Figure 2-2, non-industrial uses of products containing CPEs water/wastewater is not a quantifiable pathway.

23

releases from manufacturing and processing, recycling and disposal, as well as consumer use from

residences and commercial settings. EPA could utilize wastewater monitoring data to identify

geographic locations with higher than average exposures and to identify major sources of

contamination. This may be a useful tool in qualitative assessment of risk (as described above), enabling

EPA to gain a better understanding of the overall exposure landscape.

VII. The purpose of clustering chemicals should be made more transparent.

The Agency clustered the flame retardant chemicals according to structural similarly,

presumably because clustered chemicals may exhibit similar toxicity characteristics, use, and exposure

patterns, or be used as alternatives for one another (although this is not explicitly described in the

documents). We generally support the use of clusters as a way to organize the data, identify data needs

across chemicals, and investigate potential synergies.

However, in conducting these risk assessments and developing future Problem Formulation and

Initial Assessment documents, we request greater transparency as to the envisioned or actual utility of

the clusters. Before EPA extrapolates hazard, exposure or risk values, or conclusions from one chemical

to the other members of a cluster, it would need to demonstrate that the chemicals have very similar

types and extents of toxicity and exposure (which has not been done in the present documents). A

cluster does not equate to a robust chemical category (i.e., chemicals that have been shown to behave

very similarly with respect to physical, chemical, and biological activity).

VIII. EPA should establish and make publicly available a risk assessment development and completion schedule.

EPA should make public a target schedule for the draft and final assessments of TSCA Work Plan

chemicals. Using this schedule, the status of individual assessments should be tracked and reported.

Further, if EPA diverges from the schedule, a public explanation should be provided.

The schedules included in EPA’s Integrated Review Plans (IRPs) – which serve a similar function

as the current documents for the Agency’s National Ambient Air Quality Standards (NAAQS) – serve as a

24

good model. For example, the 2014 IRP for the Nitrogen Dioxide NAAQS44 outlines an “Anticipated

schedule,” including major milestones and target dates from the initial stages of review through risk

management steps (p. 2-3).

EDF appreciates the opportunity to provide these comments to the Agency on these important

scoping documents.

Sincerely,

Lindsay A. McCormick Jon Choi Research Analyst High Meadows Fellow

Richard A. Denison, Ph.D. Jennifer McPartland, Ph.D. Lead Senior Scientist Senior Scientist

44

US EPA, 2014. “Integrated Review Plan for the Primary National Ambient Air Quality Standards for Nitrogen Dioxide.” Available at: http://www3.epa.gov/ttn/naaqs/standards/nox/data/201406finalirpprimaryno2.pdf.