A P E R [E S E A R C H]{.smallcaps} C [O U N C I L]{.smallcaps}

[1250 Connecticut Avenue, NW, Suite 700, Washington, DC
20036]{.smallcaps}

[toll free: 866-aperc-na www.aperc.org info@aperc.org]{.smallcaps}

ALKYLPHENOLS & ETHOXYLATES RESEARCH COUNCIL

**COMMENTS ON EPA'S PROPOSED**

**AMBIENT AQUATIC LIFE WATER QUALITY CRITERIA FOR NONYLPHENOL DOCUMENT**

#### January 5, 2004; 69 [Fed]{.underline}. [Reg]{.underline}. 340; Docket ID No. OW-2003-0080

# 

# I. Introduction

The Alkylphenols & Ethoxylates Research Council (APERC) appreciates this
opportunity to submit comments in response to the U.S. Environmental
Protection Agency's (EPA) draft "Ambient Aquatic Life Water Quality
Criteria for Nonylphenol," announced in the Federal Register on January
5, 2004 (69 [Fed]{.underline}. [Reg.]{.underline} 340). APERC's
membership[^1] is comprised of the major North American manufacturers
and processors of alkylphenols, most notably nonylphenol (NP), as well
as derivatives of NP including nonylphenol ethoxylates (NPEs). As such,
APERC and its members have a unique interest in this proceeding.

The alkylphenol industry wholeheartedly endorses EPA's efforts to
establish an aquatic life water quality criteria (WQC) for NP. APERC
encourages EPA to proceed expeditiously to finalize these criteria so
that they can be considered by states and tribes in setting their own
state specific standards as well as regulatory and other public health
agencies outside the U.S.

APERC believes that the Agency has considered most of the relevant
studies on NP and that the aquatic life water quality criteria derived
by EPA are generally supportable. At the same time, APERC's review
reveals that EPA has not consistently applied its Guidelines in
determining which test results to consider in the WQC derivation.
Additionally, there are several places in the draft Criteria document,
particularly in the important Introductory section, where EPA's
characterization of the available science is not fully reflective of the
most relevant information available on nonylphenol. APERC encourages EPA
to revise this section to more accurately characterize the environmental
fate and effects of NP.

### II. EPA Should More Fully Reflect the Pathways for NP Entering the Environment

In the Introductory section of the draft Criteria document, EPA
correctly notes that NP predominately enters the environment from the
degradation of NPE (page 2, paragraph 2). However, the document as
drafted gives the impression that most of the NPE that enters the
environment will degrade to NP; this is simply not the case.

NP is not the predominant degradation product of NPE. As reflected on
the attached chart, the two predominant degradation pathways for NPE are
through the loss of ethylene oxide units to form low-mole ethoxylates or
through the formation of carboxylated ethoxylates. As these degradation
intermediates further degrade, they do not form NP, but they are broken
down to ring-opened and other water soluble fragments, carbon dioxide
and water, as well as become part of microbial biomass.

In fact, the formation of NP is the minor degradation pathway. The
degradation of NPE to NP occurs under anoxic conditions as noted in
Giger *et al*., 1984. Such conditions may be found in:

-   anoxic \"dead spots\" within sewer pipes and aeration basins;

-   anaerobic digestion systems used to reduce the volume of sludge and
    the concentration of ammonia; and,

-   in buried anoxic sediment and landfills.

While the degradation of NP is slow in these anoxic settings, the
compound is not readily bioavailable. Furthermore, a significant
percentage of the NP formed within anoxic waste treatment plants will be
adsorbed onto dewatered sewage sludge and either incinerated, placed in
landfills, or used as a soil amendment, where it will continue to
degrade.

APERC encourages EPA to revise the Criteria document to reflect that NP
is not the primary degradation product formed from NPE as this
principally occurs in anoxic conditions. Once the NP enters an
oxygenated environment, either in surface water, surficial sediment, or
soil, it does not persist and will continue to degrade to
mineralization.

**III. Levels of NP in the Environment Are Typically Below the Proposed
WQC**

The draft Criteria document (page 2) presents several studies that
report the presence of NP in water, sediment and fish. APERC believes
that in revising this section, EPA should clarify that the important
issue is not the detection of these compounds in the environment but the
level at which they are found in relation to the WQC. Additionally, EPA
should focus on levels of NP found in ambient waters of the United
States and not in other parts of the world. For example, some of the
results presented are 20 years old and include measurements for water
bodies outside the U.S. Since the primary purpose of the document is to
provide guidance to states and tribes for purposes of establishing their
own criteria and discharge limitations, it is important to focus the
document on the most recent comprehensive surveys of NP concentrations
in U.S. waters.

Data of particular relevance that should be more comprehensively
discussed include measurements of NP in the Great Lakes (as reported by
Bennie, 1999), a comprehensive study of a small watershed in Michigan
(Keith *et al*., 2001 and Kannan *et al*., 2003[^2]), a survey of 30
rivers that was designed with the assistance of the EPA (Weeks *et al*.,
1996[^3]) and a survey of approximately 140 streams known to receive
effluents from sewage treatment plants (Kolpin *et al*., 2002[^4]).
These studies are more relevant to discuss because they are
representative of the waters of the U.S. and they show that NP is
typically found in surface waters at levels below the proposed WQC -- in
fact the concentration of NP is typically less than 1 microgram per
liter.

EPA should consider referencing the conclusions the Agency previously
reached in its RM-1 document prepared as part of the evaluation under
the Toxic Substances Control Act (Rodier, 1996). The RM-1 document
concluded that on a national basis, NP does not pose a significant risk
to aquatic organisms.

In the limited cases where NP has been reported at concentrations higher
than the proposed WQC, it is generally associated with inefficient
wastewater treatment plants and effluent dominated streams. These
environments often suffer from general contamination problems that could
be best remedied not by focusing on controlling any specific compound,
but rather through a more comprehensive program that likely involves
upgrading wastewater treatment capabilities.

**IV. EPA Mischaracterizes the Fate of NP in the Environment**

In the discussion on the environmental fate of NP/NPE found on pages
2-4, information on the biodegradation of NP and NPE is intertwined with
reports of ambient monitoring data. APERC recommends that EPA clearly
separate the discussions on the fate of NP in wastewater treatment
plants (arguably this is not the "ambient environment") from the
characterization of NP's biodegradation in environmental waters and
sediments. As noted in the criteria document, detailed studies on the
fate of NP (and NPEs) in wastewater treatment plants have been
conducted. Maguire (1999) documents that secondary sewage treatment
plants can easily and extensively remove these compounds from aqueous
waste streams through both degradation and sorption to solids.

In the discussion of the degradation of NP in aqueous media, there are
several studies referenced in the Criteria document that are not
adequately utilized to describe the extent to which the degradation of
NP occurs. Of particular significance are the reports by Staples *et
al*., 1999 and 2001,[^5] Sundaram and Szeto, 1981 and Ahel *et al*.,
1994c. Collectively, these studies show that NP released into surface
waters is subjected to biodegradation, photolysis and some deposition to
sediment. They reported that NP degrades (biodegradation and photolysis)
in freshwater with half-lives of less than 30 days and in saltwater with
half-lives of 58 days. Also, NP continues to biodegrade in surficial
sediments. Ekelund *et al.* (1993) reported similar half-lives in a
study with saltwater and sediment. The study by Heinis *et al*. (1999)
shows a half-life (dissipation time) of 66 days from sediment.

NP also degrades, but at slower rates, in buried anoxic sediments. As
already noted, the presence of NP in buried anoxic sediments should be
of limited concern as the compound is generally not bioavailable in this
environment. Thus, EPA should divide the current section on
environmental fate, located on pages 2-4 of the Criteria document, into
three separate sections: a) characterization of the fate of NP in the
aquatic environment; b) description of NP formation and fate within
sewage treatment plants, and; c) description of processes that remove NP
from being bioavailable to aquatic wildlife (*i.e*., deep burial in
anoxic zones). APERC suggests that EPA consider drawing on the
conclusions from EPA's RM-1 document and Maguire (1999). The RM-1 noted
that while NP was not readily biodegradable it should not be considered
persistent. Additionally, the RM-1 highlights that "POTWs in the U.S.
seem to have a very high efficiency in removing 4-NP".

**V. Field Studies Should Be Given Greater Consideration in Assessing
Bioaccumulation Potential**

The draft Criteria document summarizes much of the available information
on the ability of NP to bioconcentrate and biomagnify in the food chain.
Overall, EPA concludes that NP has a low potential to bioaccumulate in
aquatic organisms. While APERC does not disagree with EPA's
characterization, this conclusion can be strengthened by making greater
utilization of the available field studies (presented in Staples *et
al*., 1998) which show that field bioaccumulation factors (BAFs) are
much lower than laboratory-derived lipid-normalized bioconcentration
factors (BCFs).

It is also relevant to note that the laboratory BCFs and field BAFs are
considerably lower than would be predicted due to strict partitioning.
Since the measured log Kow of NP is 4.3 (Kow=20,000), the potential
bioaccumulation factors are predicted to be higher, absent consideration
of metabolism of the NP within the organisms. The results from the
laboratory BCFs and field BAFs show that NP is extensively metabolized
in aquatic organisms and only accumulates to a limited degree.

> **A. EPA Should Correct the Reported Bioconcentration Factor for
> Algae**

On page 4, paragraph 2, EPA cites a study by Ahel *et al.* (1993) as
suggesting that NP bioconcentrates in algae 10,000 times. EPA needs to
be careful in its use of this result since it is reported on a dry
weight basis rather than the more traditional wet weight basis. Assuming
that the macrophyte algae is 95% water, Staples *et al*. (1999)
determined that the dry weight value of 10,000 L/kg can be converted on
a wet weight basis to 487 L/kg.

VI\. EPA Should Consistently Apply the EPA Guidance for Determining the
Acceptability of Studies Used in the Development of Criteria

There are several instances in the EPA draft Criteria document where the
Agency appears to have inconsistently applied its guidance for
determining the appropriateness of using certain studies in deriving the
aquatic life criteria.

In a study by England (1995), *Ceriodaphnia dubia* were exposed to NP
for 7 days, enabling effects to be discerned from both acute (48 hour)
and chronic (7 day) exposures. While EPA relied on the chronic data, the
Agency excluded the acute data since the organisms were fed. As such,
this study was not used in deriving the acute to chronic ratio (see
Table 2b).

APERC questions the appropriateness of excluding the results from this
study as the data were generated from a study that followed standard
protocols as well as EPA and international standards of Good Laboratory
Practices (GLP). The study also included comprehensive analysis of the
test substance.

EPA's exclusion of the acute results from England 1995 is in contrast
with the Agency's decision to include, for purposes of deriving the salt
water WQC, studies involving feeding. In the case of salt water, EPA
justified the use of results from feeding studies, noting that there was
not a consistent difference in LC50 values from fed and non-fed studies.
EPA noted that for mysids, feeding increased the LC50 value slightly,
while for sheepshead minnow, feeding reduced the LC50 value.

It is APERC's view that EPA should consistently apply the guidance for
selection of studies for consideration in deriving a WQC. Since there
are not very many comparative acute and chronic values from which to
derive the WQCs, APERC believes that EPA should reconsider its dismissal
of the England acute results. This is particularly relevant since, in
contrast with England 1995, the feeding studies that EPA used in
deriving the saltwater values do not appear to have been conducted
following GLP nor did the studies measure NP concentrations.

# VII. The Section on Endocrine Response Should Be Revised

APERC suggests that EPA consider modifying the "endocrine" section
(pages 4-5) since it includes various statements that are not grounded
with the same degree of scientific support as the rest of the document;
as such, their inclusion detracts from the scientific credibility of the
document. APERC has developed several specific suggestions for EPA's
consideration.

> **A. General Studies Not on NP Should Be Removed**

There are numerous studies documenting so called endocrine responses
from exposure to wastewater treatment plant effluents. As EPA is well
aware, natural and synthetic estrogens are considered the dominant
compounds in waste treatment effluents capable of triggering endocrine
responses in fish. The fact that NP may be one of many compounds in the
effluent is not adequate to associate an estrogenic response with NP;
therefore, such studies should not be included in a formal Criteria
document. To include studies on general wastewater treatment merely
because NP has been shown or is even conjectured to be present in the
effluent, is inappropriate.

The draft Criteria document cites several studies that fall into this
category that should be excluded from the final report. For example, the
draft document cites Purdom *et al.* (1994) who reported that rainbow
trout exposed to outfalls of sewage treatment plants had increased
vitellogen concentrations. The authors speculated that the response
could be associated with estrogenic substances present in the effluents
including ethynylestradiol and nonylphenol. As this study did not
directly associate NP with the increased vitellogen, it should not be
included in the dossier.

Similarly the studies by Allen *et al.,* 1999, Harries *et al.,* 1997,
Lye *et al.,* 1999 and Tanghe *et al*., 1999 cited in the Criteria
document involved demonstrating that the waters from rivers and
estuaries below sewage treatment plants have the ability to induce
estrogenic effects in a yeast assay and in fish. These authors
speculated that the observed effects could be due to mixtures of
xenoestrogens, human estrogens, and other compounds, including perhaps
NP in the effluent. The inference that NP may be responsible for the
observed estrogenic effects is pure speculation and is unlikely given
the mixture of potent hormonally active products in the effluents.

**B. EPA Should Carefully Distinguish Between In Vitro From In Vivo
Studies**

APERC further believes EPA should more carefully distinguish between
endocrine responses that are found from *in vitro* assays from those
associated with whole animal, *in vivo* studies. As the Agency is well
aware, the ability of a compound to trigger a response in an *in vitro*
assay is not necessarily indicative of the compounds ability to generate
an apical, biologically significant response *in vivo*. It is
particularly important to make this distinction when addressing
biomarkers such as increased vitellogen, which have uncertain
physiological significance.

# 

# VIII. Clarification Regarding the Description of NP and Associated CAS Registration Numbers 

Commercial nonylphenol is a complex mixture of isomers, which results
from the natural variation in the starting materials. Several CAS
Registration Numbers have been used to describe these products. Since
manufacturers of NP use essentially the same starting materials and
synthesis process, commercially available NP products have a comparable
isomeric content.

The draft Criteria Document is directed at two CAS Numbers: 84852-15-3
and 25154-52-3. While these are the two dominant numbers used in the
marketplace, CAS Number 104-40-5 should also be specified as it is also
used to represent commercial NP. Additionally, there are several
statements in the introductory section of the document that should be
clarified. APERC offers the following edits to clarify the introductory
description of NP as well as the CAS Numbers to which the Criteria
document applies. Deletions are indicated by strikeouts and additions
are indicated by underlines.

[Recommended Revisions to Introduction of Proposed WQC Document for
NP]{.underline}

> Nonylphenol (C~15~H~24~O) is produced from cyclic intermediates in the
> refinement of petroleum and coal-tar crudes. It is manufactured by
> alkylating phenol with mixed isomeric nonenes in the presence of an
> acid catalyst. The [resulting]{.underline} product is a mixture of
> [various isomers of nonylphenol]{.underline} ~~alkylphenols~~,
> predominantly *para*-substituted [nonylphenol]{.underline}, ([Phenol,
> 4-nonyl-, branched, CAS No., 84852-15-3]{.underline}; 4-nonylphenol,
> ~~;~~ CAS No. 104-40-5[; and Phenol, nonyl , CAS No.
> 25154-52-3]{.underline}) ~~and occasionally~~ [with small amounts
> of]{.underline} *ortho*-substituted (2-nonylphenol; CAS No. 136-83-4),
> [and trace amounts of 2,4 dinonylphenol (phenol, dinonyl, branched;
> CAS No. 84962-08-3 ). Additional isomers, which represent the numerous
> branched structures that occur within the nonyl (nine carbon) group,
> add to the complexity of the compound.]{.underline} ~~with various
> isomeric, branched-chain nonyl (nine carbon) groups. (~~ Commercial
> [nonylphenol is most accurately described by CAS No. 84852-15-3
> (Phenol, 4-nonyl-branched), but]{.underline} ~~mixtures~~ ~~containing
> specified amounts of nonylphenol isomers and 2,4-dinonylphenol~~ ~~are
> given specific~~ CAS Numbers~~, either~~ [104-40-5 (Phenol, 4-nonyl-)
> and]{.underline} 25154-52-3 ([Phenol, nonyl) have also been used to
> describe these compounds commercially]{.underline} ~~or 84852-15-3~~.
> ~~These products were used for deriving the water criteria for
> nonylphenol.)~~ [This criteria document was derived to address these
> three commercially relevant CAS numbers, essentially representing one
> compound.]{.underline}

[^1]: Members of APERC include: Dover Chemical Corporation; Crompton
    Corporation; Great Lake Chemical Corporation; Huntsman LLC; Rhodia
    Inc.; Rohm and Haas Company; Schenectady International, Inc.; and,
    The Dow Chemical Company.

[^2]: Kannan, K., T.L. Keith, C.G. Naylor, C.A. Staples, S.A. Snyder and
    J.P. Giesy. 2003. Nonylphenol and Nonylphenol Ethoxylates in Fish,
    Sediment, and Water from the Kalamazoo River, Michigan. Arch.
    Environ. Contam. Toxicol. 44:77-82.

[^3]: Weeks, J.A., W.J. Adams, P.D. Guiney, J.F. Hall and C.G. Naylor.
    1996. Risk Assessment of Nonylphenol and its Ethoxylates in U.S.
    River Water and Sediment. The Alkylphenols & Alkylphenol Ethoxylates
    Review. 1:64-74.

[^4]: Kolpin, D.W., E.T. Furlong, M.T. Meyer, E.M. Thurman, S.D. Zaugg,
    L.B. Barber and H.T. Buxton. 2002. Pharmaceuticals, Hormones, and
    Other Organic Wastewater Contaminants in US Streams, 1999-2000: A
    National Reconnaissance. Environ. Sci. Technol. 36:1202-1211.

[^5]: Staples, C.A., C.G. Naylor, J.B. Williams and W.E. Gledhill. 2001.
    Ultimate Biodegradation of Alkylphenol Ethoxylate Surfactants and
    Their Biodegradation Intermediates. Environ. Toxicol. Chem.
    20:2450-2455.