Comments
by The Center for Regulatory Effectiveness on EPA's Preliminary Ecological
Fate and Effects Risk Assessment and Related Documents for Atrazine
(Docket No. Opp-34237a)
The
Center for Regulatory Effectiveness ("CRE") is concerned that
the above-referenced preliminary atrazine documents ("EcoTox Risk
Assessment") do not use and rely on a probabilistic risk assessment.
EPA itself acknowledges that probabilistic risk assessments are far more
useful and accurate than lower-tier analyses like the one EPA is using
for atrazine. EPA’s failure to use and rely on a probabilistic risk assessment
is bad science and bad policy. It denies the public accurate, comprehensive
and useful information concerning the ecological risks of atrazine. It
also violates the new Data Quality Act and OMB’s guidelines implementing
the Act.
If
EPA believes that methodology or data input changes should be made to
the probabilistic risk assessments already submitted by the registrant,
then EPA should request that the registrant complete a new probabilistic
risk assessment, or EPA should prepare its own, and allow public notice
and comment, prior to any risk management decision. In no event should
EPA base an atrazine EcoTox risk assessment on the lower-tier, inadequate
analysis used by the preliminary risk assessment.
Background
Months
before EPA prepared and published its EcoTox Risk Assessment, the atrazine
registrant, Syngenta, submitted a refined probabilistic risk assessment
for atrazine’s ecological effects and fate entitled Aquatic Ecological
Risk Assessment of Atrazine-A Tiered Probabilistic Approach. This
probabilistic assessment was prepared by a panel of highly regarded, independent
scientists. It concluded that
The integration
of an unusually comprehensive data set including laboratory bioassays,
field microcosm studies, simulation modeling, and environmental
monitoring revealed that atrazine does not pose an ecologically significant
risk to most aquatic environments in North America. Although direct
toxic effects on aquatic animals are very unlikely to occur, some inhibitory
effects on algae, phytoplankton or macrophyte production may occur in
certain habitats vulnerable to agricultural runnoff. These effects are
likely to be transient and recovery would be rapid.
EPA’s
EcoTox Risk Assessment does not use or rely on Syngenta’s probabilistic
risk assessment. Instead, EPA only uses and relies on a preliminary, lower
tier (Tier I/Tier II) risk analysis of atrazine’s ecological effects and
fate. Based on this "initial screening level assessment," EPA
concludes that
Direct acute effects
on birds, mammals, fish and aquatic invertebrates are not expected at
maximum use rates [of atrazine]. However, chronic effects on mammals,
birds, fish and aquatic invertebrates are possible at maximum and typical
use rates.
EcoTox Risk Assessment,
page 6.
[C]ontinued atrazine
use is likely to pose a risk to health and integrity of some aquatic
communities.
Id, page
7.
These data provide
a strong basis for concluding that the continued use of atrazine is
likely to result in adverse effects on some aquatic communities.
Id., page
9.
On
page 2 of its response to Syngenta’s comments on a draft of the atrazine
EcoTox Risk Assessment, EPA acknowledges that these conclusions and their
underlying lower-tier analysis assessment "do not imply any quantification
of magnitude or probability of effect."
According
to EPA, there are inadequate data to perform a probabilistic risk assessment
for atrazine, even though the Agency admits that there are "a relatively
large amount of both ecotoxicological data and monitoring data on atrazine...."
EcoTox Risk Assessment, pages 4-5.
By
contrast, EPA is using probabilistic risk assessments for the Agency’s
cumulative risk assessment of the organophosphate pesticides. It is hard
to believe that the available data allow valid probabilistic risk assessments
in this very complex and novel multiple-pesticide context, but do not
allow probabilistic assessment of the ecological effects of the single
pesticide atrazine, which is indisputably one of the world’s most studied
and tested pesticides.
Everyone
Agrees That Probabilistic Risk Assessments Are Necessary To Accurately
Assess Ecological Fate And Effects
EPA’s Office of Pesticide
Programs explains on its website (emphasis added):
In May 1996 the
Environmental Fate and Effects Division (EFED) of the Office of Pesticide
programs (OPP) presented two pesticide risk assessment case studies
to EPA’s Scientific Advisory Panel (SAP) and asked them to address the
agency’s current pesticide risk assessment methodology. The SAP commented
that while the current process is believed to be cautious and protective
in terms of adverse environmental effects, it best serves as a screen
because it provides little information on the likelihood of damage.
The SAP recommended that the pesticide risk assessment process be expanded
to include probabilistic assessments of risk and to identify the uncertainties
associated with the assessment.
EPA’s Ecological Committee
on FIFRA Risk Assessment Methods ("ECOFRAM") published in 1999
an Aquatic Report which on page 3 summarized the SAP’s conclusions in
part as follows (emphasis added):
The panel suggested
that the current test methodologies and specific endpoints used by OPP
in its model assessments were designed to support the relative simplistic
process of hazard assessment, not risk assessment. The Panel indicated
that the current approach has a number of limitations, and its utility
in risk assessments is of questionable value. They also pointed
out that gaps in the current methodologies must be filled to accomplish
effective and comprehensive risk assessments. As a result, they strongly
urged OPP EFED to conduct probabilistic assessments (risk assessments)
to evaluate the ecological impacts from pesticides.
In sum, the type of
lower-tier analyses used by EPA for atrazine have been subject to formal,
independent, external peer review and found lacking in this context. By
contrast, a probabilistic risk assessment, like the one submitted by Syngenta,
is the type of analysis found necessary by formal, independent, external
peer review.
Epa's Refusal To Use A Probabilistic Risk Assessment Violates The Data
Quality Act And Omb's Implementing Guidelines
The
Data Quality Act, P. L. 106-554, § 515, imposes new standards on the quality
of information disseminated by federal agencies including EPA’s pesticide
risk assessments. As required by the statute, the Office of Management
and Budget ("OMB") promulgated guidelines implementing the Act’s
new data quality standards. 66 FR 49718 (September 28, 2001). These OMB
guidelines apply to EPA’s pesticide risk assessments. EPA now has until
October 1, 2002 to promulgate its own Data Quality Act guidelines, which
must conform to OMB’s and must include a petition process by which parties
can correct information disseminated by EPA that does not comply with
the Data Quality Act and OMB’s guidelines: including pesticide risk assessments.
EPA’s
atrazine EcoTox Risk Assessment does not meet the Data Quality Act’s standards
as implemented by OMB’s guidelines. For example, it lacks "utility"
and "objectivity."
EPA’s
Current EcoTox Risk Assessment for Atrazine Lacks "Utility"
OMB’s
Guidelines under the Data Quality Act require that all information disseminated
by EPA to the public have "utility." The OMB definition of "utility"
explains that this term "refers to the usefulness of the information
to its intended users, including the public."
As
noted above, EPA’s own SAP emphasized that the type of lower-tier analyses
used by EPA instead of the atrazine probabilistic risk assessment has
"utility...of questionable value." EPA’s own SAP urged the Agency
"to conduct probabilistic assessments (risk assessments) to evaluate
the ecological impacts from pesticides." The SAP further cautioned
that the type lower-tier analysis used for atrazine "best serves
as a screen because it provides little information on the likelihood of
damage." In fact, as the SAP pointed out, this type of lower-tier
analysis "is designed to support the relative simplistic process
of hazard assessment, not risk assessment." EPA itself admits that
its lower-tier analysis does "not imply any quantification of magnitude
or probability of effect." Yet EPA is relying on it as the sole ecological
fate and effects risk assessment for atrazine. It has little if any "utility"
for this purpose
EPA’s
Current EcoTox Risk Assessment for Atrazine lacks "Objectivity
OMB’s
Guidelines also require "objectivity" in information EPA disseminates
to the public. The OMB definition of "objectivity" explains
(emphasis added), "In a scientific or statistical context, the original
or supporting data shall be generated, and the analytical results shall
be developed, using sound statistical and research methods."
EPA’s
SAP has concluded that the type of lower-tier analysis used by EPA is
not a "sound statistical...method" for pesticide ecological
risk assessments. In fact it is only a hazard assessment, not a full-fledged
risk assessment. Probabilistic risk assessments are the "sound statistical...method"
in this context, especially when one has already been prepared and submitted
to the Agency.
In
contrast EPA has relied on worst case data to imply or actually state
that atrazine will cause indirect ecological effects. This subjective
speculation does not rely on any data that remotely satisfies the new
OMB Data Quality Act requirements.
Recommendations
EPA
should promptly state publicly that it is revising its preliminary EcoTox
Risk Assessment for atrazine to incorporate the results of a probabilistic
risk assessment:
- either the probabilistic
risk assessment already submitted by the registrant;
- a new probabilistic
risk assessment prepared by the registrant, with public notice and comment,
if EPA would like methodology or data input changes; or
- a probabilistic
risk assessment prepared by EPA itself after public notice and comment
Comments
by The Center bor Regulatory Effectiveness on The Atrazine Environmental
Fate and Effects Risk Assessment
(Docket Control Number Opp-34237c)
Introduction
The
Center for Regulatory Effectiveness ("CRE") has the following
primary comments on the Environmental Fate and Effects Chapter of EPA's
Registration Eligibility Science Chapter for Atrazine ("Environmental
Risk Assessment").
First,
EPA's Environmental Risk Assessment "concluded that the
major effects from atrazine
use are indirect effects on fish and invertebrate populations...."
At the same time, EPA correctly admitted "that there is 'inadequate
data' on indirect effects to assess risk..."; and that "[c]urrently,
there is no methodology...which can model and statistically analyze indirect
effects." EFED Review of Public Comments in Response to the EPA
EFED Revised Environmental Risk Assessment for Atrazine, p. 3(April 10,
2002)("Comment Response"). EPA also correctly admittted
that there are substantial uncertainties regarding the field and laboratory
standards used to support the Environmental Risk Assessment's conclusion
of indirect effects: e.g., lack of reproducibility and lack of
transparency. Environmental Risk Assessment, pp. 63-64. Given these
admissions, EPA obviously cannot publicly disseminate a conclusion that
atrazine causes indirect effects. Any such conclusion would violate the
objectivity and utility standards of the Data Quality Act amendments to
the Paperwork Reduction Act, 44 U.S.C. § 3516 statutory and historical
notes ("Data Quality Act"). Consequently, EPA's Environmental
Risk Assessment should be revised to delete any conclusion that atrazine
causes indirect effects on wildlife.
Second,
the Environmental Risk Assessment should be revised to state that
EPA cannot use or rely on the Hayes Frog Studies because those studies
do not comply with the Data Quality Act for the following and other reasons:
- The Hayes Frog
Studies results cannot be reproduced; and
- There are no validated
test methods for aromatase induction, which is the hypothesized mode
or mechanism of action underlying the Hayes Frog Studies.
Third,
the Environmental Risk Assessment should be revised to state that
there is no acceptable
evidence of wildlife endocrine disruption from atrazine because there
are no validated test methods for endocrine disruption. The objectivity
and utility standards of the Data Quality Act preclude any conclusion
or suggestion of adverse endocrine effects until and unless there are
properly validated test methods.
Fourth,
the quotient method EPA used in the Environmental Risk Assessment
is arbitrary and lacks utility. Consequently, any conclusions based on
the quotient method violate the utility and objectivity standards of the
Data Quality Act. EPA should defer any conclusions about the environmental
effects of atrazine until EPA has developed a reliable probabilistic risk
assessment method for adverse environmental effects.
These
and other comments are discussed in more detail below.
EPA's
Environmental Risk Assessment
Cannot Assess Indirect Effects
EPA's
Environmental Risk Assessment determined that the only major environmental
risk from atrazine use was indirect effects, not direct effects: e.g.,
- "[T]he Agency
has concluded that the major effects from atrazine use are indirect
effects on fish and invertebrate populations...." Comment Response,
p. 3.
- "[T]he atrazine
effects of concern are indirect effects on the aquatic community due
to the loss of vegetative habitat." Comment Response, p. 3.
- "[T]he Agency
identified the endpoints of greatest concern as indirect effects on
aquatic communities due to loss of species sensitive to atrazine and
resulting in changes in structure and functional characteristics of
the affected communities, and reductions in populations of aquatic macrophytes,
invertebrates and fish." Environmental Risk Assessment,
p. 3.
- "[T]he Agency
notes that the results of the agency's preliminary risk assessment shows
that Levels of Concern (LOCs) are not exceeded for most of the direct
acute and chronic effects on aquatic organisms." Environmental
Risk Assessment, p. 12.
Paradoxically,
EPA also admits in its Comment Response the Agency is unable
to assess indirect environmental effects for atrazine or any other pesticide:
- "EFED contends
that there is 'inadequate data' on indirect effects to assess risk...."
Comment Response, p. 3.
- "Currently,
there is no methodology...which can model and statistically analyze
indirect effects." Comment Response, p.3.
EPA's
inability to assess indirect environmental effects is not a new phenomenon.
EPA acknowledged this flaw in its risk assessment process over ten years
ago:
Although
the Agency believes that long-term, indirect effects of pesticide use
on aquatic ecosystems may be important, the Agency does not have a testing
scheme in place to accurately measure such effects within the time specified
for Reregistration. Decisions on the Ecological, Fate, and Effects
Task Force, Linda J. Fisher, EPA Assistant Administrator, Attachment:
Program Guidance on Ecological Risk Management, p. 1 (Oct. 29, 1992).
Nothing
has changed since, as acknowledged by EPA in its atrazine Comment Response.
Moreover,
EPA used the quotient method in its Environmental Risk Assessment,
and EPA admits: "The quotient method cannot evaluate secondary effects."
61 FR 47552, 47594 (Sept. 9, 1996). EPA defines the term "secondary
effects" as an
effect where the stressor acts on supporting components of the ecosystem,
which in turn have an effect on the ecological component of interest (synonymous
with indirect effects...). Id. at 47615.
EPA
cannot inform the public that atrazine use causes indirect effects when
EPA admits that "there is no methodology...which can model and statistically
analyze indirect effects"; and "that there is 'inadequate data'
on indirect effects to assess risk...." Comment Response, p. 3.
EPA's Environmental Risk Assessment violates the Data Quality
Act's objectivity and utility requirements because EPA's conclusion that
atrazine has adverse indirect effects has no factual or scientific basis.
Consequently, this conclusion is not accurate and reliable; nor is it
useful to its intended users. 67 FR 8452, 8453 (Feb. 22, 2002)(OMB's government-wide
Data Quality guidelines).
With
regard to indirect effects, EPA also relied on some field and laboratory
studies. With regard
to the quality of these studies, EPA admitted:
This refined assessment,
while providing a greater certainty of adverse effects on aquatic life
than that based on modeled exposure and typical laboratory toxicity
values, also contains inherent uncertainties. Two important sources
of uncertainty can be attributed to the monitoring data and the laboratory
(including laboratory data on the major degradates) and field study
data themselves. The monitoring data were not collected for the purpose
of supporting an ecological risk assessment. Thus, the spatial and temporal
distributions of the monitoring data do not match those for the laboratory
toxicity studies or the field studies.
***
The laboratory and
field study data for the most part are taken from published literature.
The EPA scientists did not have access to the raw data necessary to
evaluate some of these studies as is typically done for data submitted
by registrants to support registration. Also, while a majority of the
laboratory and field toxicity data indicated similar exposure levels,
there were some studies that showed no effects at similar exposure levels.
In addition, while the laboratory toxicity data indicate adverse effects
to certain species of organisms, we cannot determine with certainty
that impacts on these or similar species would result in a loss of ecological
function or important changes in community structure in natural systems.
***
Detrimental effects
on plants are rapid are rapid and appear to increase as both the atrazine
concentration exposure increases. Prolonged exposure results in starvation
an ultimately death of plants. Rapid recovery of oxygen evolution (within
hours) is observed in aquatic plants if atrazine exposure is removed.
Plant recovery and resistence are two complicating issues which
add uncertainty to any risk assessment on atrazine, and there is insufficient
information to do more than report that both occur.
Environmental Risk
Assessment, pp. 63-64
These
field and laboratory studies do not meet the Data Quality Act's objectivity
and utility standards. EPA itself admits that "the laboratory toxicity
data" do not allow the Agency to "determine with certainty that
impacts on these or similar species would result in a loss of ecological
function or important changes in community structure in natural systems."
Moreover, the laboratory and field toxicity tests showing adverse effects
are not reproducible: "some studies... showed no effects at similar
exposure levels"; and neither EPA nor the public has access to the
underlying data. It is also inaccurate to compare monitoring data with
field and laboratory data when their "spatial and temporal distributions...
do not match." In addition, EPA acknowledges, "Plant recovery
and resistence are two complicating issues which add uncertainty to any
risk assessment on atrazine, and there is insufficient information to
do more than report that both occur." In sum, based on the current
data base, and based on the risk assessment methods used by EPA, there
is too much "uncertainty" regarding atrazine's indirect environmental
effects to reach any accurate, reliable, unbiased and useful conclusion
regarding those effects. Consequently, any conclusion regarding those
effects cannot meet Data Quality Act standards.
The
Hayes Frog Studies Do Not Meet Data Quality Standards
The
Environmental Risk Assessment suggests that the Hayes Frog Studies
show that atrazine use
causes endocrine disruption in frogs at very low concentrations, in particular
with regard to reproductive development. The Hayes Frog Studies do not
meet the Data Quality Act objectivity and utility requirements for at
least two reasons.
First,
other laboratories have been unable to reproduce them. Attached as Exhibit
A to CRE's comments are a written report and slides from a presentation
to EPA by Dr. James A. Carr of Texas Tech University. Dr. Carr was unable
to reproduce Dr. Hayes' test results. In addition, CRE understands that
Dr. John Giesy, of Michigan State University, has been unable to reproduce
Dr. Hayes' test results, but has not yet prepared a written report on
his tests. Test results that have been shown not to be reproducible do
not meet the Data Quality Act's objectivity and utility standards because
they are not accurate, reliable or useful.
Second,
Dr. Hayes hypothesizes that atrazine can cause adverse endocrine effects
in frogs because atrazine induces aromatase in the frogs. Environmental
Risk Assessment, p. 90. There are no validated test methods for aromatase
induction. Any mode or mechanism of action that relies on unvalidated
test methods does not meet the Data Quality Act's objectivity and utility
standards because the unvalidated test methods have not been demonstrated
to be accurate, reliable and useful.
In
light of the above concerns, the Environmental Risk Assessment
should be revised to state that
EPA will not use or rely on the Hayes Frog Studies because they do not
meet Data Quality Act standards.
EPA Cannot Reach Any Conclusion About Endocrine Disruption Until And
Unless There Are Validated Test Methods
EPA's
Environmental Risk Assessment at page 90 states:
Atrazine
has been reported to cause sub-lethal effects in aquatic organisms and
amphibians. These include endocrine effects in frogs at ~0.1 µg/L and
in largemouth bass at ~50 µg/L, as well as olfactory effects in salmon
at ~50 µg/L. In addition some studies have been conducted where these
effects were not demonstrated.
At
pages 90-93, the Environmental Risk Assessment contains an extensive
discussion of the relevant studies which suggests that some of them support
the conclusion that atrazine causes wildlife endocrine effects.
EPA
has also acknowledged:
The
Endocrine Disruptor Screening program has proposed a number of test protocols
for identifying endocrine effects in wildlife species. Some of these protocols
are currently in round-robin testing. As of this date, none of them have
been approved for regulatory testing.
EFED Review of
Comments from Syngenta and its Contractors about the EPA Revised Environmental
Risk Assessment for Atrazine, p. 22. (April 22, 2002).
The
Environmental Risk Assessment in its current state violates the
Data Quality Act's objectivity
and utility standards because it indicates that atrazine does cause endocrine
effects in wildlife based on studies using unvalidated test methods. EPA
should revise its Environmental Risk Assessment to clearly state
that EPA cannot reach any conclusions about wildlife endocrine effects
from atrazine until and unless there are properly validated test methods
for those effects.
The Quotient Risk
Assessment Method is Arbitrary and Lacks Utility
As in the case of
most if not all pesticides, EPA used the quotient method to assess atrazine's
environmental risks:
The standard method
used in the EPA Office of Pesticide Programs (OPP) to characterize ecological
risk is the ratio or quotient method. "Typically, the ratio (or
quotient) is expressed as an exposure concentration divided by an effects
concentration: (U.S. EPA, Part A, Section 5.1.3). A risk quotient (RQ)
is the ratio of the estimated environmental concentration of a chemical
to a toxicity test effect level for a given species. It is calculated
by dividing an appropriate exposure estimate (e.g., EEC or estimated
environmental concentration) by an appropriate toxicity test effect
level (e.g. LC50). Thus, the RQ is an index (an indicator or measure
of a condition) of the potential adverse effects. As an index, the risk
quotient needs some reference point or bearing to have meaning. Thus,
the Agency has established Levels of Concern (LOCs) in order to identify
when the potential adverse effects are of concern to the Agency (See
Appendix XVI, Table 1). LOCs are criteria used to indicate potential
risk to nontarget organisms and the need to consider regulatory action.
When an LOC is exceeded, it means that a pesticide, when used as directed,
has the potential to cause adverse effects on nontarget organisms.
Environmental Risk
Assessment, p. 5
The
referenced Appendix Table contains the LOCs that EPA has established for
all pesticide environmental risk assessment. These LOCs do not vary from
pesticide to pesticide.
EPA's
refined risk assessment for atrazine's environmental effects consisted
primarily of computer modeling of atrazine concentrations in various surface
waters based on the available monitoring data. The model results
were then compared to the LOCs. Environmental risk assessment, pp.
4-5, 7-8, 16.
EPA's
Office of Pesticide Programs has explained on its website that the quotient
risk assessment method lacks utility (emphasis added):
The [SAP] panel
suggested that the current test methodologies and specific endpoints
used by OPP in its model assessments were designed to support the relative
simplistic process of hazard assessment, not risk assessment. The Panel
indicated that the current approach has a number of limitations, and
its utility in risk assessments is of questionable value. They also
pointed out that gaps in the current methodologies must be filled to
accomplish effective and comprehensive risk assessments. As a result,
they strongly urged OPP EFED to conduct probabilistic assessments (risk
assessments) to evaluate the ecological impacts from pesticides.
The
SAP has emphasized its concern "with the notion that the frequency
of LOC exceedances is a useful measure." The SAP concluded that the
LOC-exceedance standard is "essentially an arbitrarily selected threshold."
FIFRA Scientific Advisory Panel, Final Report on a Set of Scientific
Issues Being Considered by the Environmental Protection Agency Regarding
Methodology for Conducting Comparative Ecological Risk Assessments,"
p. 9 (SAP Report No. 99-01A, Jan. 22, 1999).
EPA's
use of the quotient method in the Environmental Risk Assessment
violates the Data Quality Act's utility and objectivity requirements because
this method is not accurate, reliable or useful in assessing the indirect
or other environmental effects of atrazine.
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