United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued April 22, 2002 Decided June 28, 2002
No. 01-1296
American Forest and Paper Association, Inc.,
Petitioner
v.
Environmental Protection Agency,
Respondent
On Petition for Review of an Order of the
Environmental Protection Agency
Russell S. Frye argued the cause for the petitioner. Rich-
ard Wasserstrom was on brief. Christina B. Parascandola
entered an appearance.
Andrew J. Doyle, Attorney, United States Department of
Justice, argued the cause for the respondent. Patrice Simms
and Patricia Embrey, Attorneys, United States Environmen-
tal Protection Agency, were on brief.
Before: Ginsburg, Chief Judge, Henderson and Rogers,
Circuit Judges.
Opinion for the court filed by Circuit Judge Henderson.
Karen LeCraft Henderson, Circuit Judge: The American
Forest and Paper Association, Inc. (Association), a national
trade association of the forest, paper and wood products
industry, seeks review of a notice published by the Environ-
mental Protection Agency (EPA) denying the Association's
petition to delete the substance methanol1 from the list of
"hazardous air pollutants" (HAPs) pursuant to section 112(b)
of the Clean Air Act (CAA), 42 U.S.C. s 7412(b). See 66 Fed.
Reg. 21,929 (May 2, 2001). Section 112(b)(3)(A) requires that
EPA "either grant or deny the petition by publishing a
written explanation of the reasons for the Administrator's
decision." 42 U.S.C. s 7412(b)(3)(a).2 We review EPA's
notice of denial under the Administrative Procedure Act to
determine whether it is "arbitrary, capricious, an abuse of
discretion, or not in accordance with law." 5 U.S.C.
s 706(2)(A).3 For the reasons set out below, we conclude
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1 Methanol, also known as "wood alcohol," is a clear liquid that is
released into the air when wood is processed.
2 Section 112(b)(2) describes HAPs as
pollutants which present, or may present, through inhalation or
other routes of exposure, a threat of adverse human health
effects (including, but not limited to, substances which are
known to be, or may reasonably be anticipated to be, carcino-
genic, mutagenic, teratogenic, neurotoxic, which cause repro-
ductive dysfunction, or which are acutely or chronically toxic)
or adverse environmental effects whether through ambient
concentrations, bioaccumulation, deposition, or otherwise, but
not including releases subject to regulation under subsection (r)
of this section as a result of emissions to the air.
42 U.S.C. s 7412(b)(2).
3 The Association erroneously argues that EPA is required to
issue a far more extensive decision under CAA section 307(d)(9), 42
U.S.C. s 7606(d), one "that includes the factual data on which the
rule is based, the methodology used in obtaining and analyzing the
data, the major legal interpretations and policy considerations
underlying the rule, and a response to comments or criticisms of
EPA's explanation of its reasons for denying the delisting
petition satisfies the statutory standard and we therefore
deny the Association's petition for review.
I.
Section 112 requires EPA to set emission standards for
"hazardous air pollutants." See 42 U.S.C. s 7412. In 1990
the Congress amended section 112 to establish a statutory list
of HAPs, including methanol. See 42 U.S.C. s 7412(b)(1).
Section 112(b)(2) requires that EPA "periodically review the
list" and "publish the results thereof and, where appropriate,
revise such list by rule, adding pollutants." 42 U.S.C.
s 7412(b)(2). Section 7412(b)(3) provides that "any person
may petition the Administrator to modify the list of hazardous
air pollutants under this subsection by adding or deleting a
substance." Id. s 7412(b)(3)(A). EPA is required (1) to "add
a substance to the list upon a showing by the petitioner or on
the Administrator's own determination that the substance is
an air pollutant and that emissions, ambient concentrations,
bioaccumulation or deposition of the substance are known to
cause or may reasonably be anticipated to cause adverse
effects to human health or adverse environmental effects," id.
s 7412(b)(3)(B); and (2) to "delete a substance from the list
upon a showing by the petitioner or on the Administrator's
own determination that there is adequate data on the health
and environmental effects of the substance to determine that
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EPA's proposed action." Pet'r Br. at 45. CAA section 307(d)(9),
however, by its terms applies only to "rulemakings" pursuant to the
CAA sections enumerated in section 307(d)(1), 42 U.S.C.
s 7607(d)(1). Section 112(b) does not contemplate a formal rule-
making and is not among the sections enumerated in section
307(d)(1) (although other subsections of section 112 are included
there). EPA was therefore not required to respond point-by-point
to each objection raised in the Association's comments below. Its
decision may be upheld as long as EPA did not "entirely fail[ ] to
consider" "an important aspect of the problem." See Motor Vehicle
Mfrs. Ass'n of the United States, Inc. v. State Farm Mut. Auto. Ins.
Co., 463 U.S. 29, 43 (1983).
emissions, ambient concentrations, bioaccumulation or deposi-
tion of the substance may not reasonably be anticipated to
cause any adverse effects to the human health or adverse
environmental effects," id. s 7412(b)(3)(C).
The Association petitioned EPA to delist methanol in
March 1996, relying on information it claimed shows exposure
to methanol does not result in adverse effects to human
health.4 "[T]o assess the potential for adverse human health
effects due to inhalation exposure" to a particular substance
EPA generally uses an "inhalation reference concentration"
(RfC), 66 Fed. Reg. at 21,931, which "represents the estimat-
ed maximum exposure to a pollutant, as extrapolated from
animal studies, that a human can tolerate continuously for 70
years without experiencing any adverse health effect," Chem.
Mfrs. Ass'n v. EPA, 28 F.3d 1259, 1265 (D.C. Cir. 1994).
Because EPA had not yet established an inhalation RfC for
methanol, the Association proposed a "safe exposure level"
(SEL) for the substance, asserting that "exposures at or
below the SEL can be expected to produce no adverse human
health effects from lifetime inhalation exposures." 66 Fed.
Reg. at 21,931. The Association derived its SEL from the
"Rogers Study," which examined the effect on mice of metha-
nol exposure for seven hours per day. The Association
converted the No-Observable-Adverse-Effect-Level
(NOAEL) derived from the Rogers Study to a human equiva-
lent and adjusted it for interspecies extrapolation and for
individual variation. The Association offered the resulting
level of 83 milligrams per cubic meter (mg/m3) as the SEL for
methanol. The Association further asserted that the highest
predicted 24-hour average concentration of methanol from
known sources is 3.65 mg/m3. Because this maximum expo-
sure level was below its proposed SEL, the Association
claimed that methanol exposure does not cause adverse ef-
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4 The Association also offered evidence to show methanol does not
cause adverse environmental effects but, because it denied the
petition based on potential adverse health effects, EPA found it
unnecessary "to make final determinations regarding these ele-
ments of the petition." 66 Fed. Reg. at 21,939. Accordingly, we
too decline to address the environmental issues.
fects and therefore should be delisted pursuant to section
112(b)(3)(C). The Association supplemented its petition peri-
odically until EPA published a "notice of receipt of a complete
petition" on July 19, 1999. See 64 Fed. Reg. 38,668. Subse-
quently the Association submitted additional materials ad-
dressing the "Burbacher Study," published in October 1999,
which examined the effects of methanol inhalation on pri-
mates and which the Association contended supports delisting
methanol.
Following a comment period, EPA issued its notice of
denial on May 2, 2001. While generally approving the studies
and the methodology the Association had used, EPA disa-
greed with the Association's analysis in three crucial respects.
First, EPA took issue with the Association's SEL, contend-
ing it should have incorporated a "duration adjustment," to
account for the difference between the Rogers Study's 7-hour
daily exposure and potential human daily exposure of 24
hours;5 and, in addition, it should have been derived using the
"benchmark dose" (BMD) methodology6 rather than using the
NOAEL methodology as the Association did. EPA deter-
mined that recalculating the SEL using a duration adjust-
ment and the BMD methodology "would yield an SEL on the
order of 4-6 mg/m3." 66 Fed. Reg. at 21,932. Because these
values "are at the approximate midpoint of the values (0.3-30
mg/m3) that might be derived from the data of the Burbacher
Primate Study," EPA concluded that "a range of 0.3 to 30
mg/m3 represents the most appropriate criterion for deter-
mining whether methanol emissions may reasonably be antici-
pated to cause adverse human health effects" and that "24-
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5 The Association initially proposed an SEL of 24 mg/m3 which
reflected a duration adjustment but subsequently advocated the
higher 83 mg/m3 SEL without a duration adjustment. See Delisting
Petition at 2, 30-32; 66 Fed. Reg. at 21,932.
6 BMD "is defined as the statistical lower confidence limit on the
dose estimated to produce a predetermined level of change in
response (the benchmark response--BMR) relative to controls."
Proposed Test Rule for Hazardous Air Pollutants, 61 Fed. Reg.
33,178, 33,179-80 (1996).
hour exposures below 0.3 mg/m3 are not likely to result in
adverse human health effects." 66 Fed. Reg. at 21,935-36.
EPA cautioned that it was "unable to make a more precise
determination at this time regarding the exposure levels at
which adverse effects are likely to occur." 66 Fed. Reg. at
21,936.
Second, EPA challenged the Association's maximum 24-
hour exposure level as too low. Based on the data initially
submitted by the Association, EPA suggested that the "maxi-
mum 24-hour exposures to methanol emissions could be in
the range of 2 to 7 mg/m3, but that such exposures may not
reasonably be expected to exceed 7 mg/m3." 66 Fed. Reg. at
21,939.
Third, EPA determined that, contrary to the Association's
contention, the Burbacher Study in fact supports retaining
methanol on the list because it revealed several possible
adverse health effects, namely, a decrease in gestation time,
an increase in the number of required caesarian-section
births, and, in prenatally exposed offspring, instances of a
"severe wasting syndrome," concentration-related delay in
sensorimotor development and lower performance on an in-
fant intelligence test. 66 Fed. Reg. at 21,932-33. EPA
concluded that, "based on the weight of evidence, ... there
are reproductive and developmental health consequences fol-
lowing exposure to methanol in primates (Burbacher et al.)
and that these effects should be considered relevant to poten-
tial risks in humans." 66 Fed. Reg. at 21,935.
Because EPA's maximum exposure level exceeded the floor
of its SEL range and because the Burbacher Study, as EPA
construed it, indicated potential adverse effects from metha-
nol, EPA determined it "c[ould ]not conclude that there are
adequate data to determine that emissions of methanol may
not reasonably be anticipated to cause any adverse effects to
human health." 66 Fed. Reg. at 21,929.
The Association petitioned for review of the notice of denial
on July 2, 2001.
II.
The Association raises a series of challenges to the EPA's
notice of denial. We find none of them persuasive.
First, the Association asserts EPA misinterpreted the stat-
utory standard for delisting a substance to permit it to rely
on mere speculation about adverse effects. Section
112(b)(3)(C) requires that EPA delist an HAP "upon a show-
ing by the petitioner or on the Administrator's own determi-
nation that there is adequate data on the health and environ-
mental effects of the substance to determine that emissions,
ambient concentrations, bioaccumulation or deposition of the
substance may not reasonably be anticipated to cause any
adverse effects to the human health or adverse environmental
effects." 42 U.S.C. s 7412(b)(3)(C). EPA construed the
statutory language to impose a "burden ... on a petitioner to
demonstrate that the available data support an affirmative
determination that emissions of a substance may not be
reasonably anticipated to result in adverse effects on human
health or the environment" so that "EPA will not remove a
substance from the list of HAP based merely on the inability
to conclude that emissions of the substance will cause adverse
effects on human health or the environment." 66 Fed. Reg.
at 21,930. We review EPA's construction of the statutory
language under
the familiar Chevron analysis:
If ... " 'Congress has directly spoken to the precise
question at issue,' " we "must give effect to Congress's
'unambiguously expressed intent.' " Secretary of La-
bor v. F[ed. Mine Safety & Health Review Comm'n],
111 F.3d 913, 917 (D.C. Cir.1997) (quoting Chevron
USA, Inc. v. Natural Resources Defense Council, Inc.,
467 U.S. 837, 842, 104 S.Ct. 2778, [2781], 81 L.Ed.2d
694 (1984)). "If 'the statute is silent or ambiguous
with respect to the specific issue,' we ask whether the
agency's position rests on a 'permissible construction
of the statute.' " Id. (quoting Chevron, 467 U.S. at
843, 104 S.Ct. 2778, [2782], 81 L.Ed.2d 694).
Cyprus Emerald Resources Corp. v. Fed. Mine Safety &
Health Review Comm'n, 195 F.3d 42, 45 (D.C. Cir. 1999).
National Multi Housing Council v. EPA, No. 01-1159, slip
op. at 4 (D.C. Cir. June 7, 2002). EPA's interpretation easily
passes muster under Chevron. The statutory language un-
ambiguously places on a delisting petitioner the burden to
make a "showing" that "there is adequate data" about a
substance to determine exposure to it "may not reasonably be
anticipated to cause" adverse effects. This is precisely what
EPA has construed it to require. To the extent the Associa-
tion asserts EPA improperly applied the burden by relying on
speculation, its assertion dovetails with its arbitrary-and-
capricious arguments, which we address next.
The Association challenges EPA's technical calculations on
a variety of grounds. According EPA the "extreme degree of
deference" it is due when "evaluating scientific data within its
technical expertise," see Huls Am., Inc. v. Browner, 83 F.3d
445, 452 (D.C. Cir. 1996) (internal quotations and citations
omitted), we find its calculations are not arbitrary or capri-
cious.
The Association argues that EPA's decision fails a "reality
check" in two respects. First, the Association points out that
methanol levels far higher than the maximum predicted for
industrial source exposure have been reported in unexposed,
healthy humans and primates, particularly in the expelled
breath of study subjects who had recently consumed substan-
tial amounts of fruit. In the notice of denial, EPA set forth
specific reasons why the methanol levels in study subjects'
mouths after fruit consumption may not correspond to--and
may in fact considerably exceed--the actual methanol levels
in the subjects' blood. See 66 Fed. Reg. at 21,935 (noting
there was "no discussion as to whether these individuals
rinsed their mouths out after consuming the fruit" and no
"correction for off-gassing of methanol from the residual
mouth contents or stomach contents"); see also Joint Appen-
dix (JA) 824-25. EPA also noted that the high levels of
methanol measured represented "an extreme case" and that
consumption of fruit sufficient to produce them "most likely
involves acute GI effects sufficient to discourage the at-
tempt." 66 Fed. Reg. at 21,935. Second, the Association
contends that pharmacokinetic models show that an SEL of
0.3 mg/m3 causes only a minuscule and inconsequential in-
crease in an exposed subject's blood methanol level. EPA
has reasonably rejected the Association's pharmacokinetic
models as "not targeted to humans likely to be the most
sensitive to methanol," notably pregnant women, developing
fetuses and persons with enzyme and vitamin deficiencies.
See Resp't Br. at 57; JA 824 (noting "uncertainty in the
[Association's interspecies] extrapolations, notably character-
ization of pregnancy and fetal transfer" which can be ad-
dressed "with the use of newer physiologically-based pharma-
cokinetic models"); 755-56 (summary of meeting between
Association and EPA indicating EPA scientist stated "EPA
needs to see a data set of methanol levels in pregnant
women").7 In addition, EPA noted the possible short window
of exposure for adverse developmental effects to occur in
developing fetuses and its consequent concern that, despite
natural fluctuations in background methanol blood levels,
there is a risk of negative effects from even short term peaks.
See JA 476, 755.8
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7 The Association asserts EPA "apparently ignor[ed] the fact that
the pharmacokinetic data in the HEI Report were in pregnant
female primates, and those data show no effect of pregnancy on
methanol distribution or metabolism." Reply Br. at 9 (emphasis
original). The HEI Report acknowledged, however, that "although
Burbacher found that formate did not accumulate in maternal blood,
the present study does not resolve the issue of possible formate
accumulation in fetal tissues." JA 449.
8 The Association challenges EPA's justifications here, and else-
where, as improperly post hoc. The record excerpts we cite,
however, reveal that EPA relied below, at least in part, on the same
reasoning it espouses here. See National Mining Ass'n v. Mine
Safety & Health Admin., 116 F.3d 520, 534 (D.C. Cir. 1997) ("In
evaluating agency action, we look at the reasons given by the
agency, not 'counsel's post hoc rationalizations.' Motor Vehicle
Mfrs. [Assoc. v. State Farm, 463 U.S. 29, 50 (1983)]. ' "[W]e will,
however, 'uphold a decision of less than ideal clarity if the agency's
Next, the Association challenges EPA's decision to calcu-
late the SEL using the BMD methodology (specifically, the
BMDL-5 lower confidence level) rather than the NOAEL.
In the Association's view, the BMD introduces an "unex-
plained, unacknowledged level of conservativism," Pet'r Br. at
22,9 and is, in any event, an untested, experimental approach.
"We may reject an agency's choice of a scientific model 'only
when the model bears no rational relationship to the charac-
teristics of the data to which it is applied.' " See National
Wildlife Fed'n v. EPA, 286 F.3d 554, 562 (D.C. Cir. 2002)
(quoting Appalachian Power Co. v. EPA, 135 F.3d 791, 802
(D.C. Cir. 1998) (citing Am. Iron & Steel Inst. v. EPA, 115
F.3d 979, 1005 (D.C. Cir. 1997); Chem. Mfrs. Ass'n v. EPA,
28 F.3d 1259, 1265 (D.C. Cir. 1994))). That is not the case
here. EPA has long advocated the BMD as superior to the
NOAEL because "[u]nlike the NOAEL, the BMD takes into
account dose-response information." See The Use of the
Benchmark Dose Approach to Health Risk Assessment, at 2
(Feb. 1995) (available at http://www.epa.gov); see also EPA
Draft Benchmark Dose Technical Guidance Document, at 3
(Oct. 2000) (available at http://www.epa.gov) ("[T]he BMD
approach is an alternative to the NOAEL/LOAEL approach
that has been used for many years in dose-response assess-
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path may reasonably be discerned." ' Id. at 43, 103 S.Ct. at 2866
(quoting Bowman Transp., Inc. v. Arkansas-Best Freight Sys.,
Inc., 419 U.S. 281, 286, 95 S.Ct. 438, 442, 42 L.Ed.2d 447 (1974))");
Southern Pac. Transp. Co. v. ICC, 69 F.3d 583, 594 (D.C. Cir. 1995)
("The ultimate question, however, is whether the court can discern
the agency's path, based on the record and not on post hoc
justifications.").
9 The Association similarly contends, in footnotes, that EPA
should not have used a duration adjustment. EPA concluded "the
current state of scientific understanding tends to support incorpo-
rating duration-adjustment in the petitioner's derivation of SEL,"
noting its position was "also consistent with studies showing that
the critical period for induction of developmental toxicity from
methanol exposure can be at least as short as 1-2 days." JA 476.
The Association offered nothing below contradicting these conclu-
sions or their bases.
ment. The development of this approach has been pursued
because of recognized limitations in the NOAEL/LOAEL
approach."). The BMD's advantages over NOAEL have also
been acknowledged by private researchers, including those in
the Rogers Study who calculated a BMD for methanol. See
John M. Rogers et al., The Toxicity of Inhaled Methanol in
the CD-1 Mouse, with Quantitative Dose-Response Modeling
Estimation Benchmark Dose, 47 Teratology 175, 176-77
(1993). Thus, EPA's choice of the BMD methodology was not
arbitrary.
As for EPA's choice of BMD confidence level, the Associa-
tion asserted, citing its technical comments below, that the
BMDL-5 adds an unjustified "level of conservativism" based
on the fact that the BMDL-5 produces a much lower SEL
than does the NOAEL. EPA, however, took a contrary view
as did, apparently, the Rogers Study researchers who applied
the identical BMD. The "presence of disputing expert wit-
nesses" offers " 'a classic example of a factual dispute the
resolution of which implicates substantial agency expertise' "
and requires that we " 'defer to the informed discretion of the
responsible federal agencies.' " Wisconsin Valley Improve-
ment Co. v. FERC, 236 F.3d 738, 746-47 (D.C. Cir. 2001)
(quoting Marsh v. Oregon Natural Resources Council, 490
U.S. 360, 376 377 (1989) (internal quotation omitted)). We
defer here to EPA's resolution of the dispute.
The Association also challenges EPA's determination that
the "maximum 24-hour exposures could be in the range of 2
to 7 mg/m3." 66 Fed. Reg. at 21,929. We need not resolve
this issue, however, because the lower exposure level the
Association proposed--3.65 mg/m3--also exceeds EPA's
threshold SEL of 0.3 mg/m3 (which we uphold) and therefore
does not support delisting.
Next, the Association, relying on a report by the Health
Effect Institute (HEI), which sponsored the Burbacher
Study, asserts EPA arbitrarily attributed to methanol expo-
sure the adverse effects observed in the Burbacher Study.
We believe EPA's findings were reasonable. The HEI Re-
port itself recognized a possible connection between methanol
and the decreased gestation time, suggesting that "[f]urther
studies will be required to confirm the association between
low-level methanol exposure and effects on pregnancy dura-
tion." JA 377. Similarly the HEI Report acknowledged that
"prenatal methanol exposure was associated with the occur-
rence of a wasting syndrome in females after approximately 1
year of age" but concluded that "further investigations are
needed to confirm these findings." JA 425. Nor did the
HEI Report rule out methanol exposure as the cause of the
increased need for caesarian-sections but simply determined
that "conclusions concerning methanol exposure as a caus-
ative factor in uterine bleeding are not warranted at this
time." JA 377 (emphasis added).10 Finally, the HEI Report
recognized that "[m]ethanol exposure was also associated
with a delay in early sensorimotor development for male
infants" and that "[t]he results of the Fagan Test of Infant
Intelligence indicated a possible effect of methanol exposure
on visual recognition memory when complex stimuli (social
problems) were used in testing." JA 425. In sum, the HEI
Report confirms EPA's position that the study data indicate
methanol may reasonably be anticipated to cause adverse
health effects but are insufficient at this time to determine
conclusively that it does or does not.
Finally, the Association claims EPA violated the express
directive in section 112(b)(3)(A) that EPA "may not deny a
petition solely on the basis of inadequate resources or time
for review." 42 U.S.C. s 7412(b)(3)(A). We disagree. EPA
reviewed the Association's petition thoroughly and at great
length, repeatedly requesting additional submissions before it
deemed the Association's petition complete. In the end,
based on its analyses, EPA concluded, consistently with the
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10 The Association also cites an expert opinion that the research-
ers inaccurately concluded the caesarian-section deliveries were
necessary. EPA, however, was entitled to rely on the opinion of the
Burbacher Study researchers rather than on the opinion of the
Association's expert. See Wisconsin Valley Improvement Co., 236
F.3d at 746-47. In any event, there is no dispute regarding the
increase in vaginal bleeding. See JA 370.
statute, that the Association had not produced sufficient data
to satisfy its statutory burden.11
For the foregoing reasons, the petition for review is
Denied.
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11 The Association also contends that, "[i]n at least six respects,
[it] raised points in its petition that were of such import that they
might have changed EPA's determination, and yet EPA failed to
respond to those points or explain why it was denying the [Associa-
tion's] petition in spite of those points." Pet'r Br. at 45. We reject
these assertions because, as the foregoing discussion indicates, none
of the six points cited (failure of the reality check, objection to the
BMDL-5 methodology and the arguments against attributing to
methanol exposure the neurobehavioral effects observed in the
Burbacher Study) is "an important aspect of the problem" that EPA
"entirely failed to consider." See Motor Vehicle Mfrs. Ass'n of the
United States, Inc. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29,
43 (1983).