United States
 Environmental Protection
Office of Water
  June 1995
Information Document
on Aquatic Life
Toxicity for:
 Phthalate (DEHP)


Environmental Protection Agency
40 CFR Part 131, 401.15, 423; Appendix A
Environmental Protection Agency
Action: Notice of Availability of an Information Document on
Aquatic Life Toxicity for Di-2-Ethylhexyl Phthalate (DEHP)
The U. S. Environmental Protection Agency (EPA) is
announcing the availability of an information document on aquatic
life toxicity
for Di-2-Ethylhexyl Phthalate (DEHP).
water quality criteria documents are developed pursuant to
section 304(a) (1) of the Clean Water Act.
The current guidelines
for ambient water quality criteria for the protection of aquatic
life specify the data needed for development of a national
Sufficient acute and chronic toxicity data for DEHP
were not available to derive a national criteria.
For this
reason, EPA is announcing the availability of an information
document which presents only lowest observed effect levels
(LOEL's) for DEHP.
The group of chemicals commonly referred to as phthalates
are esters of phthalic acid.
Phthalates are used in the
manufacture of plastics where they increase the flexibility,
extensibility and workability of plastic.
Phthalate is the Phtalate compound that is produced in the
largest volume.

A copy of the comments/responses and supporting documents
(cited in the Reference section of this document) are available
for review at EPA's Water Docket; 401 M street, S.W.; Washington,
D.C. 20460.
For access to Docket materials, call (202) 260-3027
between 9:00 a.m. and 3:30 p.m. for an appointment.
Requests for copies of the supporting documents should be sent
u.s. Environmental Protection Agency
National Center for Environmental Publications
and Information
11029 Kenwood Road
Cinncinati, OH 45242
(513) 489-8190
Internet address: Waterpubs@EPAmail.EPA.gov
Mr. Patrick Ogbebor
Health and Ecological Criteria Division(4304)
u.s. Environmental Protection Agency
401 M street, S.W.
Washington, DC 20460
(202) 260-0658

EPA publishes and periodically updates ambient water quality
criteria pursuant to section 304(a) (1) of the Clean Water
Act, (33)U.S.C. 1314(a) (1).
These criteria are intended to
reflect the latest scientific knowledge on the identifiable
effects of pollutants on public health and welfare, aquatic life
and recreation.
Beginning in 1973, EPA has periodically issued
ambient water quality criteria.
In July 1976, EPA published "Quality criteria for Water -
1976", which provided a freshwater aquatic life criteria for
phthalate esters.
A criterion value of 3 ug/L was established
based on available acute and chronic data.
Four years later, EPA published a notice of availability
of "Ambient Water Quality Criteria for Phthalate Esters" in the
Federal Register, (45 FR 79318, November 28, 1980), (Ref. 2).
This document established a Lowest Observed Effect Level (LOEL)
of 3 ug/L for aquatic life, based on acute and chronic data.
addition this document greatly expanded the data base considered
for this chemical.
A draft aquatic life criteria document for DEHP was made available
for public comment on May 14, 1990, (55 FR 1986).
This draft proposed
establishing a chronic criteria of 360 ug/L and an acute criteria of
400 ug/L for both freshwater and saltwater.
EPA is announcing the
availability of an information document on aquatic life toxicity for
Di-2-Ethylhexyl Phthalate for the protection of freshwater and

saltwater aquatic organisms.
This final document was derived after
consideration of all comments received and following analysis of

additional data received after the draft document was published in
Summary of Information Document on Aquatic Life Toxicity for
Di-2-Ethylhexyl Phthalate
The procedures described in the "Guidelines for Deriving Numerical
National Water Quality criteria for the Protection of Aquatic Organisms
and Their Uses",
(hereafter referred to as the Guidelines) do not allow
for the derivation of national criteria for Di-2-Ethylhexyl Phthalate
(DEHP), based on the available test information.
Limited data indicate that acute toxicity occurs to freshwater
aquatic life at a concentration as low as 2,000 ug/L, which is above
the reported solubility limit for DEHP. Based on water solubility
values which ranged from 270 ug/L to 400 ug/L, the mean concentration
of 334 ug/L was calculated as the best estimate of water solubility for
DEHP for this document.
Chronic toxicity occurs to one freshwater
species at a concentration as low as 160 ug/L, and would occur at lower
concentrations among untested species that are more sensitive.
DEHP toxicity data for saltwater aquatic life is limited.
if the chronic sensitivity of saltwater aquatic life to DEHP is similar
to that of freshwater aquatic life, adverse effects on individual
species might be expected at S 160 ug/L.

Data on the acute toxicity of DEHP are available for fourteen
species of freshwater animals and four saltwater organisms.
In nearly

species of freshwater animals and four saltwater organisms.
nearly all acute tests, the highest concentrations tested were
not acutely toxic.
Therefore, only "greater-than" the tested
concentrations could be reported in this document.
A final
acute value for freshwater or saltwater organisms cannot be
calculated because not enough definitive acute values exist to
meet the minimum data base requirements according to the
No final value, as defined in the Guidelines, can be
calculated for either freshwater or saltwater plants.
There is
no Food & Drug Administration(FDA) action level or an available
maximum dietary intake value derived from a chronic feeding study
or a long-term field study with wildlife.
A final acute value cannot be calculated for DEHP, and only
two acute-chronic ratios are available as greater-than values;
therefore, no final chronic value for DEHP can be calculated
using the final acute-chronic ratio procedure according to the

Response to Publio Comments on the Information Dooument on
Aquatio Life Toxioity for Di-2-Ethylhexyl Phthalate
Comments to the draft criteria document were made by the
Chemical Manufacturers Association (CMA), American
Water Works Association (AWWA), Monsanto Company, state of Ohio

Environmental Protection Agency, Dow Chemical USA, Detroit Water
and Sewerage Department, State of Maryland Department of the
Environment, Utility Act Group.
The following are responses to comments by several
organizations on the draft document for Di-2-Ethylhexyl Phthalate
(DEHP), which was published in the Federal Register on May 14,
(55 FR 11986, Docket No. OW-FRL-3762-9).
The draft, dated
9/24/87, was revised by ERL-Duluth and ERL-Narragansett, based on
these comments and additional literature information.
EPA has
chosen not to issue numerical national criteria for DEHP instead
of the criteria initially proposed in the Federal Register draft,
most of the comments are no longer issued.
However, EPA has
responded to each comment for the record.
The following comments represent a summary of the most
important comments received.
The complete response to public
comment document can be obtained by contacting the Office of
Water Resource Center at the previously noted address.
Commentor - EPA should withdraw the numerical criteria Maximum
Concentration (CMC) for DEHP and replace it with a narrative
criterion of "free from floating material".
The EPA should not

publish the final aquatic life criteria values that are strictly
based on solubility for DEHP.
EPA should not use the solubility
limit as a surrogate for a CMC.
The approach of using solubility
results is unnecessarily stringent criteria.
The EPA should not
set water quality criteria in situations where no toxicity has
been observed.
CMA recommends that EPA formally withdraw the
1980 phthalate esters criteria document with notice in the
Federal Register to avoid confusion and misunderstanding that
result from continued use of this document.
Response - EPA agrees that the CMC for DEHP, as stated in the
9/24/87 draft document, should not be used.
EPA acknowledges the
fact that a numerical CMC cannot be calculated for Di-2--
Ethylhexyl Phthalate because not enough of the available acute
toxicity test information provides definitive toxicity endpoints
(i.e.,LC50s) for calculating a Final Acute Value for either
freshwater or saltwater organisms, according to the "Guidelines
for Deriving Numerical National Water Quality criteria for the
Protection of Aquatic Organisms and Their Uses", hereafter
referred to as the Guidelines.
Several studies shows that DEHP
is not toxic at the tested concentrations.
This results in
"greater than" LC50's for most tests with freshwater organisms
and for all tests with saltwater organisms.
Most often,
concentrations greatly exceed the water solubility limit of 334

ug/L; EPA's best estimate based on the current literature.
Therefore, EPA will not issue a freshwater or saltwater CMC for
DEHP based on the available acute test information.

information presented in this document will supersede previous
national aquatic life water quality criteria for DEHP (U.S. EPA,
1976 1980 (Ref.
I and 3 respectively).
Commentor - The criteria continuous Concentration (CCC) for DEHP
should be recalculated using data previously submitted to EPA by
the CMA Phthalate Esters Panel as part of a voluntary testing
program under section 4 of TSCA.
The CCC for DEHP should be
established at 200 ug/L based on available chronic toxicity data
although it is less rigorous than the EPA Guidelines approach.
The current chronic guidance value for all phthalate esters
should be publicly withdrawn immediately.
EPA should calculate
separate CMC's and CCC's for freshwater and saltwater organisms.
Response - EPA acknowledges that not enough chronic toxicity
tests are available to provide definitive endpoints for
calculating the chronic values for DEHP.
This lack of
information combined with the lack of definitive acute
information also does not allow for calculation of a Final
Chronic Value, according to the Guidelines.
Therefore, EPA will
not issue a freshwater or saltwater CCC for DEHP based on the
available chronic test information.
However, one chronic
toxicity test indicates that DEHP is toxic to Daphnia magna (a
freshwater cladoceran) at concentrations below DEHP's water
solubility limit of 334 ug/L.
Data provided by CMA show that
DEHP concentrations as low as 160 and 290 ug/L are chronically
toxic to this species.
These results conflict with those from
other studies which indicate that DEHP is only toxic to this same

species at concentrations above solubility (358 to 5,394 ugjL).
Because of the large uncertainty associated with this range of
results combined with limited definitive chronic data for DEHP,
there is concern that this group of aquatic species could be
affected unacceptably if populations are exposed for long periods
of time to DEHP at concentrations ~ 160 ugjL.
EPA is not recommending any CCC for DEHP, CMA's
recommendation of using 200 ugjL as the CCC for this chemical is
no longer an issue.
However, this value cannot be recommended as
a "level of concern" because CMA's own data show that
concentrations ~ 160 ugjL are chronically toxic.
In addition, it
is possible that untested concentrations that are lower than 160
ugjL could be toxic to cladocerans since the chronic value
calculated from CMA's study is 110 ugjL, and effect
concentrations could occur at still lower concentrations among
untested freshwater species that are more sensitive than
Toxicity data for DEHP and saltwater aquatic life is very
if their chronic sensitivity to DEHP is
similar to that of freshwater aquatic life, adverse effects on
individual species might be expected at ~ 160 ugjL.
An ecosystem
process, ammonia flux, has been shown to be reduced at 15.5 ugjL
during summer months.
Commentor - Since human health and aquatic life criteria address
different uses of a water body, EPA should view these criteria
Two separate criteria should be based on sound

scientific studies which are available for public review and
Response - Information for deriving water quality criteria for
the protection of human health and aquatic life are gathered
independently of each other and are currently used separately for
preparing individual criteria documents for human health and
aquatic life protection.
The 1987 draft document only included
information on DEHP and aquatic life.
In addition, the 1985
Guidelines do not involve human health concerns except for FDA
action levels for fish oil or the edible portion of fish or
DEHP does not have a FDA action level at this time;
therefore, aquatic life criteria cannot be influenced by residue
that are used in connection with the protection of human health.
Commentor - The draft document assumes that DEHP is equal in
toxicity to freshwater and saltwater organisms.
A minimum data
set for saltwater species should be derived with which to
calculate saltwater criteria.
Water quality factors such as pH,
hardness, alkalinity and temperature can playa major role in the
toxicity of a constituent.
Ideally, the water quality factors
likely to impact the toxicity of a constituent should be
determined and factored into the development of the criteria
continuous Concentration (CCC) and the Criteria Maximum
Concentration (CMC) numbers.
If this is not performed, the
states should be allowed flexibility to set water quality
criteria based on both positive and negative influence from other
water quality factors.

Response - EPA agrees that there is not enough data to meet the
minimum data base for deriving criteria for saltwater organisms
and will not issue a saltwater criteria for DEHP.
EPA agrees
that water quality factors can playa major role in the toxicity
of a chemical and already uses this type of information for
deriving criteria, if it is available.
Although more
information is needed to discern correlations between the above
stated factors and the toxicity of DEHP, the limited current
information on this chemical does not indicate that such
correlations exist.
At the present time, states are allowed the flexibility to
derive criteria with any data that are acceptable to the
Guidelines and, in addition, are allowed to modify national
criteria to site-specific criteria to better reflect local
conditions including instances where the above factors may impact
Commentor - The latest comprehensive literature searches for
information for the DEHP document was conducted four years ago.
This information document, therefore, may already be out of date.
More timely literature searches should be conducted for this an
criteria documents.
Response - EPA agrees that the literature search for this
document is out of date and a new search was conducted in
September of 1992.
New information from this search has been
added to the revised document.

Commentor - Many different water solubilities for DEHP are given
in the published literature.
How did EPA arrive at 400 ug/L as
the water solubility for DEHP?
Response - Many values for DEHP water solubility are indicated in
various published studies.
However, only the values derived from
studies specifically designed to measure water solubility were
considered useable in the 1987 draft (270, 300, 340, 360 and 400
ugjL), and the highest value of 400 ug/L was chosen to provide
the most liberal estimate of the amount of DEHP that would be
possible in aqueous solution.
However, EPA has now revised the
estimate to be 334 ugjL by using the mean concentration from the
five values listed above.
Comment or - The bioconcentration discussion in the document lacks
information on the metabolism of DEHP by fish and reported
are for total 14C analyses, not DEHP.
Response - Information now included in the revised draft document
for DEHP shows that DEHP can be metabolized by fish (Barron et
The Bioconcentration Factors (BCF's) Environmental
Protection Aqencv: AWOC for DEHP - Paqe 8 of 8 reported in Table
5 of this draft are based on measurements of 14C in water and
tissue and most likely include concentrations of both DEHP and
stable metabolites.
Consequently, these factors are probably
overestimating the bioaccumulation potential of DEHP in the
organisms shown in table 5 of the 1987 draft document.
since the concentrations of actual DEHP relative to the
concentrations of it's metabolites are not known for the

Notice of Availability of Information Document on Aquatic Life
Toxicity for Di-2-Ethylhexylphthalate (DEHP) page 13 of 14
organisms listed, the bioconcentration factor are EPA's best
estimate of DEHP bioaccumulation.
EPA also agrees that more
information is needed to better estimate DEHP bioaccumulation in
aquatic organisms.
since there is no FDA action limit or an
available maximum dietary intake value derived from a chronic
feeding study or a long-term field study with wildlife, a Final
Residue Value (FRV) for DEHP cannot be calculated and, therefore,
criteria based on a FRV cannot be derived at this time.
Dated: J1t~)~ r6~
e>-JuJ) 4);;J.
Tudor T. Davies, Director
Office of Science and Technology

u.s. EPA; "Quality criteria for Water-1976"; EPA-440/9-76
023; NTIS # PB 263-943.
National Technical Information Service.
Springfield, VA. pp.191-192.
Federal Reqister notice November 28, 1980; 45 FR 79339.
:3 .
"Ambient Water Quality criteria
for Phthalate
Esters" October 1980,
EPA Draft "Ambient Water Quality criteria for Di-2
Ethylhexy1 Phthalate; September 24, 1987; 440/5-87-013
Stephen, C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A
Chapman and W.A. Brungs. 1985 ; 822R85100. "Guidelines for
Deriving National Water Quality Criteria for the Protection of
Aquatic organisms and Their Uses".
Technical Information Service Springfield, Va.
Barron, M.G., I.R. Schultz and W.L. Hayton. 1989.
presystemic brachial metabolism limits di-2-ethylhexyl phthalate
accumulation in fish.
Pharmacol 98:48-57.