Grant v. BP Exploration & Production, Inc. et al

Filing 62

ORDER AND REASONS granting 44 Motion in Limine to Exclude the Causation Testimony of Plaintiff's Expert, Dr. Jerald Cook; granting 45 Motion for Summary Judgment for the reasons stated herein. Signed by Judge Sarah S. Vance on 7/6/2022. (mm)

UNITED STATES DISTRICT COURT
EASTERN DISTRICT OF LOUISIANA
MARCUS GRANT

CIVIL ACTION

VERSUS

NO. 17-4334

BP EXPLORATION &
PRODUCTION, INC., ET AL.

SECTION “R” (4)

ORDER AND REASONS
Before the Court is BP Exploration & Production, Inc., BP American
Production Company, and BP p.l.c.’s (collectively the “BP parties”) motion to
exclude the testimony of plaintiff’s general causation expert, Dr. Jerald
Cook.1 Plaintiff Marcus Grant opposes the motion.2 Also before the Court is
the BP parties’ motion for summary judgment. 3 Plaintiff also opposes this
motion.4
For the following reasons, the Court grants defendants’ motion to
exclude the testimony of Dr. Cook.

1

2
3
4

Without Dr. Cook’s expert report,

R. Doc. 44. The remaining defendants, Halliburton Energy Services,
Inc., Transocean Deepwater, Inc., Transocean Holdings, LLC, and
Transocean Offshore Deepwater Drilling, Inc. join the BP parties’
motion to exclude the testimony of Dr. Cook. R. Doc. 44-1 at 1 n.1.
R. Doc. 49.
R. Doc. 45. The remaining defendants also join the BP parties’ motion
for summary judgment. R. Doc. 45-1 at 1 n.1.
R. Doc. 47.
1

plaintiff cannot establish the general causation element of his claim at trial.
Accordingly, defendants’ motion for summary judgment is also granted.

I.

BACKGROUND
This case arises from plaintiff Marcus Grant’s alleged exposure to toxic

chemicals following the Deepwater Horizon oil spill in the Gulf of Mexico.
Plaintiff alleges that he worked as a “[r]ecovery tech[nician]” on the beaches
of Pascagoula, Jackson, and Horn Island, Mississippi from September 1, 2011
through December 31, 2011. 5 Grant asserts that he “cleaned oil and oilcovered debris from sand and coastal areas,” and as a result, was exposed to
both oil and dispersants. 6 Plaintiff also represents that this exposure has
resulted in the following conditions that “persist today:” breathing
difficulties, bronchitis, “SOB,” throat irritation, congestion, headaches,
anxiety, impetigo, convulsions, seizures, eye burning, eye irritation, skin
itchiness, lesions, boils, cellulitis of lower extremit[ies], dermatitis tinea
corpus, and decreased sense of smell. 7

5
6
7

R. Doc. 44-2 at 3-4.
Id. at 3, 5.
R. Doc. 44-3 at 1.
2

Grant’s case was originally part of the multidistrict litigation (“MDL”)
pending before Judge Carl J. Barbier. His case was severed from the MDL
as one of the “B3” cases for plaintiffs who either opted out of, or were
excluded from, the Deepwater Horizon Medical Benefits Class Action
Settlement Agreement. 8 Grant is a plaintiff who opted out of the settlement.9
After plaintiff’s case was severed, it was reallocated to this Court. Plaintiff
asserts claims for general maritime negligence, negligence per se, and gross
negligence against the defendants as a result of the oil spill and its cleanup. 10
To demonstrate that exposure to crude oil, weathered oil, and
dispersants can cause the symptoms Grant alleges in his complaint, he offers
the testimony of Dr. Jerald Cook, an occupational and environmental
physician. 11 Dr. Cook is plaintiff’s sole expert offering an opinion on general
causation. 12 In his report, Dr. Cook utilizes a “general causation approach to
determine if a reported health complaint can be from the result of exposures

8

9
10
11
12

In re Oil Spill by Oil Rig “Deepwater Horizon” in the Gulf of Mex., on
Apr. 20, 2010, No. MDL 2179, 2021 WL 6053613, at *2, 12 & n.12 (E.D.
La. Apr. 1, 2021).
R. Doc. 1-1 at 2.
R. Doc. 29 ¶¶ 19-49.
R. Doc. 44-4 at 5 (Cook Report).
Plaintiff has also retained Dr. Rachel Jones, a certified industrial
hygienist, to provide a report describing “the common, or shared,
occupational exposures among worker[s]” who participated in the
Deepwater Horizon response and cleanup. R. Doc. 49-16 at 4 (Jones
Report).
3

sustained in performing [oil spill] cleanup work.” 13 Dr. Cook concludes that
“general causation analysis indicates” that the following conditions “can
occur in individuals exposed to crude oil, including weathered crude oil:”
chronic rhinitis, chronic sinusitis, allergic rhinitis, chronic obstructive
pulmonary disease (“COPD”), bronchitis, asthma, reactive airway disease,
dermatitis, skin irritation, skin rash, skin itching, acute conjunctivitis,
chronic conjunctivitis, and dry eye disease. 14
The BP parties now move to exclude Dr. Cook’s expert opinion, arguing
that it is unreliable and unhelpful. 15 Defendants also move for summary
judgment, asserting that if Dr. Cook’s general causation opinion is excluded,
plaintiff is unable to carry his burden on causation. 16 Plaintiff opposes both
motions.17 The Court considers the parties’ arguments below.

13
14
15
16

17

R. Doc. 44-4 at 14 (Cook Report).
Id. at 86-87, 92, 99.
R. Doc. 44.
R. Doc. 45-1 at 10 (“Once [defendants’ Daubert] motion is granted, the
plaintiff will be left without an admissible opinion on general causation
. . . [which] would justify summary judgment.”).
R. Docs. 47 & 49.
4

II.

MOTION TO EXCLUDE DR. COOK’S TESTIMONY
A.

Legal Standard

The district court has considerable discretion to admit or exclude
expert testimony under Federal Rule of Evidence 702. See Gen. Elec. Co. v.
Joiner, 522 U.S. 136, 138-39 (1997); Seatrax, Inc. v. Sonbeck Int’l, Inc., 200
F.3d 358, 371 (5th Cir. 2000). Rule 702 provides that an expert witness
“qualified . . . by knowledge, skill, experience, training, or education may
testify” if:
(a) the expert’s scientific, technical, or other specialized
knowledge will help the trier of fact to understand the
evidence or determine a fact in issue;
(b) the testimony is based on sufficient facts or data;
(c) the testimony is the product of reliable principles and
methods; and
(d) the expert has reliably applied the principles and
methods to the facts of the case.
Fed. R. Evid. 702.
In Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579
(1993), the Supreme Court held that Rule 702 “requires the district court to
act as a gatekeeper to ensure that ‘any and all scientific testimony or evidence
admitted is not only relevant, but reliable.’” Metrejean v. REC Marine
Logistics, LLC, No. 08-5049, 2009 WL 3062622, at *1 (E.D. La. Sept. 21,
2009) (quoting Daubert, 509 U.S. at 589). This gatekeeping function applies

5

to all forms of expert testimony. See Kumho Tire Co. v. Carmichael, 526 U.S.
137, 147 (1999).
The Court’s gatekeeping function consists of a two-part inquiry into
reliability and relevance. First, the Court must determine whether the
proffered expert testimony is reliable. The party offering the testimony bears
the burden of establishing its reliability by a preponderance of the evidence.
See Moore v. Ashland Chem. Inc., 151 F.3d 269, 276 (5th Cir. 1998). The
reliability inquiry requires the Court to assess whether the expert’s reasoning
and methodology underlying the testimony are valid. See Daubert, 509 U.S.
at 593. The aim is to exclude expert testimony based merely on subjective
See id. at 590. “[F]undamentally

belief or unsupported speculation.

unsupported” opinions “offer[] no expert assistance to the [trier of fact]” and
should be excluded. Guile v. United States, 422 F.3d 221, 227 (5th Cir.
2005). The Court may consider several nonexclusive factors in determining
reliability, including: (1) whether the technique has been tested, (2) whether
the technique has been subject to peer review and publication, (3) the
technique’s potential error rate, (4) the existence and maintenance of
standards controlling the technique’s operation, and (5) whether the
technique is generally accepted in the relevant scientific community.
Burleson v. Tex. Dep’t of Crim. Just., 393 F.3d 577, 584 (5th Cir. 2004). The
6

Supreme Court has emphasized that these factors “do not constitute a
‘definitive checklist or test.’” Kumho, 526 U.S. at 150 (quoting Daubert, 509
U.S. at 593). Rather, courts “have considerable leeway in deciding in a
particular case how to go about determining whether particular expert
testimony is reliable.” Id. at 152.
“The reliability analysis applies to all aspects of an expert’s testimony:
the methodology, the facts underlying the expert’s opinion, the link between
the facts and the conclusion, et alia.” Knight v. Kirby Inland Marine Inc.,
482 F.3d 347, 355 (5th Cir. 2007) (internal quotation marks omitted).
“Where the expert’s opinion is based on insufficient information, the analysis
is unreliable.” Paz v. Brush Engineered Materials, Inc., 555 F.3d 383, 388
(5th Cir. 2009). Further, the Supreme Court has explained that “nothing in
either Daubert or the Federal Rules of Evidence requires a district court to
admit opinion evidence that is connected to existing data only by the ipse
dixit of the expert.” Joiner, 522 U.S. at 146. Rather, “[a] court may conclude
that there is simply too great an analytical gap between the data and the
opinion proffered.” Id.
Second, the Court must determine whether the expert’s reasoning or
methodology “fits” the facts of the case, and whether it will thereby assist the
trier of fact to understand the evidence. In other words, it must determine
7

whether it is relevant. See Daubert, 509 U.S. at 591. “Expert testimony
which does not relate to any issue in the case is not relevant and, ergo, nonhelpful.” Id. (quoting 3 J. Weinstein & M. Berger, Weinstein’s Evidence ¶
702[02] (1988)).
A district court’s gatekeeper function does not replace the traditional
adversary system or the role of the jury within this system. See id. at 596. As
noted in Daubert, “[v]igorous cross-examination, presentation of contrary
evidence, and careful instruction on the burden of proof are the traditional
and appropriate means of attacking shaky but admissible evidence.” Id.
Thus, in determining the admissibility of expert testimony, the district court
must accord the proper deference to “the jury’s role as the proper arbiter of
disputes between conflicting opinions.” United States v. 14.38 Acres of
Land, More or Less Situated in Leflore Cnty., Miss., 80 F.3d 1074, 1077 (5th
Cir. 1996).

B.

Discussion

Grant has the burden of “prov[ing] that the legal cause of [his] claimed
injury or illness is exposure to oil or other chemicals used during the
response.” In re Oil Spill by Oil Rig “Deepwater Horizon” in Gulf of Mex.,
on Apr. 20, 2010, No. MDL 2179, 2021 WL 6053613, at *11 (E.D. La. Apr. 1,
8

2021) (noting that B3 plaintiffs, such as Grant, must prove that their alleged
personal injuries were “due to exposure to oil or other chemicals used during
the oil spill response”). The Fifth Circuit has developed a “two-step process
in examining the admissibility of causation evidence in toxic tort cases.”
Knight, 482 F.3d at 351. First, plaintiff must show general causation, which
means that he must show that “a substance is capable of causing a particular
injury or condition in the general population.” Id. Second, if the Court
concludes that plaintiff has produced admissible evidence on general
causation, it must then determine whether plaintiff has shown specific
causation, in other words, that “a substance caused [that] particular
[plaintiff’s] injury.” Id. If the Court finds that there is no admissible general
causation evidence, there is “no need to consider” specific causation. Id.
(citing Miller v. Pfizer, Inc., 356 F.3d 1326, 1329 (10th Cir. 2004)).
At issue here is whether plaintiff has produced admissible general
causation evidence. To prove that exposure to the chemicals in oil and
dispersants can cause the medical conditions Grant alleges, plaintiff offers
the testimony of an environmental toxicologist, Dr. Cook. Dr. Cook asserts
that his report is “based on the scientific methods used in the field of
environmental toxicology.” 18 More specifically, he states that his “causation

18

R. Doc. 44-4 at 5 (Cook Report).
9

analysis regarding health effects of oil spill exposures draw[s] on the process
of evaluating epidemiology studies and the work from established expert
groups similar to the Surgeon General’s Advisory Committee to make a more
likely than not conclusion.” 19
The Fifth Circuit has held that epidemiology provides the best evidence
of causation in a toxic tort case. See Brock, 874 F.2d at 311; Norris v. Baxter
Healthcare Corp., 397 F.3d 878, 882 (10th Cir. 2005) (noting “that
epidemiology is the best evidence of general causation in a toxic tort case”).
That is not to say that epidemiologic evidence “is a necessary element in all
toxic tort cases,” but “it is certainly a very important element.” Brock, 874
F.2d at 313. As explained by the Fifth Circuit:
Epidemiology attempts to define a relationship between a
disease and a factor suspected of causing it . . . . To define that
relationship, the epidemiologist examines the general
population, comparing the incidence of the disease among those
people exposed to the factor in question to those not exposed.
The epidemiologist then uses statistical methods and reasoning
to allow her to draw a biological inference between the factor
being studied and the disease’s etiology.
Id. at 311.
When, as here, a review of epidemiological studies forms the basis of
an expert opinion, the essential first step requires the expert to identify an

19

Id. at 16.
10

association. An association occurs when “two events (e.g., exposure to a
chemical agent and development of disease) . . . occur more frequently
together than one would expect by chance.” Fed. Judicial Ctr., Reference
Manual on Scientific Evidence 552 n.7 (3d ed. 2011) [hereinafter Reference
Manual]. 20

An association, by itself, is not equivalent to a finding of

causation. Id. at 552. Unlike an association, “[c]ausation is used to describe
the association between two events when one event is a necessary link in a
chain of events that results in the effect.” Id. at 552 n.7. The Reference
Manual indicates that “[a]ssessing whether an association is causal requires
an understanding of the strengths and weaknesses of a study’s design and
implementation, as well as a judgment about how the study’s findings fit with
other scientific knowledge.” Id. at 553. Because “all studies have ‘flaws’ in
the sense of limitations that add uncertainty about the proper interpretation
of results,” the key questions in evaluating epidemiologic evidence “are the
extent to which a study’s limitations compromise its findings and permit
inferences about causation.” Id. at 553.
Once an association is found, “researchers consider whether the
association reflects a true cause-effect relationship,” that is, whether “an

20

Dr. Cook testified in his deposition that he has reviewed the AMA
Guide’s “sections on causation,” and has used it “for purposes of [his]
work.” R. Doc. 44-7 (Dr. Cook Deposition at 60:21-61:3).
11

increase in the incidence of disease among the exposed subjects would not
have occurred had they not been exposed to the agent.” Id. at 597-98.
Alternative explanations, “such as bias or confounding factors,” should first
be considered. Id. at 598. If alternative explanations are not present,
researchers apply the Bradford Hill criteria to evaluate whether an agent can
be a cause of a disease. Id. at 597; Wagoner v. Exxon Mobil Corp., 813 F.
Supp. 2d 771, 803 (E.D. La. 2011) (“[T]he set of criteria known as the
Bradford Hill criteria has been widely acknowledged as providing an
appropriate framework for assessing whether a causal relationship underlies
a statistically significant association between an agent and a disease.”). The
Bradford Hill factors include: (1) temporal relationship; (2) strength of the
association; (3) dose-response relationship; (4) replication of findings; (5)
biological plausibility; (6) consideration of alternative explanations; (7)
cessation of exposure; (8) specificity of the association; and (9) consistency
with other knowledge. Reference Manual at 600. These factors are not
rigidly applied in a general causation analysis, but instead provide guidance
for an expert “[d]rawing causal inferences after finding an association.” Id.
Under Daubert, “courts must carefully analyze the studies on which
experts rely for their opinions before admitting their testimony.” Knight,
482 F.3d at 355; Wagoner, 813 F. Supp. 2d at 799 (“Whether epidemiological
12

studies support an expert’s opinion on the question of general causation in a
toxic tort case is critical to determining the reliability of the opinion.”).
Courts “may exclude expert testimony based on epidemiological studies
where the studies are insufficient, whether considered individually or
collectively, to support the expert’s causation opinion.” Baker v. Chevron
USA, Inc., 680 F. Supp. 2d 865, 875 (S.D. Ohio 2010) (citing Joiner, 522 U.S.
at 156-57). But a court cannot exclude expert testimony just because it
disagrees with the expert’s conclusions, although the Supreme Court has
recognized that “conclusions and methodology are not entirely distinct from
one another.” Joiner, 522 U.S. at 146.
With the above standards in mind, the Court examines Dr. Cook’s
general causation report. As noted by another section of this Court, “Cook
issued an omnibus, non-case specific general causation expert report that
has been used by many B3 plaintiffs.” Street v. BP Expl. & Prod. Inc., No. 173619, 2022 WL 1811144, at *2 (E.D. La. June 2, 2022). Dr. Cook’s report is
divided into five chapters.

The first chapter outlines Dr. Cook’s

qualifications, which are not challenged in this case. 21 The second chapter
provides an overview of the Deepwater Horizon oil spill.22 The third chapter

21
22

R. Doc. 44-4 at 5 (Cook Report).
Id. at 7-13.
13

describes Dr. Cook’s methodology, the first step of which involved his
“review and analys[is]” of the “available scientific literature to determine the
strength of an association between environmental exposure and a health
effect.”23 After reviewing the literature, Dr. Cook asserts that he selected the
epidemiological studies cited in his causation analysis “based on the quality
of the study and study design.” 24 Finally, Dr. Cook considered the studies
that found an association between a toxic agent and a disease in light of the
Bradford Hill criteria “to determine whether or not a cause-and-effect
relationship exists or not.” 25
Chapter four of Dr. Cook’s report details prior studies on the health
effects associated with oil spills. 26 This section first provides “summaries of
studies that evaluate health effects that may be associated with exposures
from oil spill response and cleanup work” in past oil spills.27 It then discusses
the findings and shortcomings of three studies on the Deepwater Horizon
oil spill: (1) the National Institute for Occupational Safety and Health’s
(“NIOSH”) Health Hazard Evaluations (“HHEs”), (2) the Deepwater
Horizon oil spill Coast Guard cohort study, and (3) the Gulf Long-Term

23
24
25
26
27

Id. at 17.
Id. at 19.
Id. at 24.
Id. at 32-64.
Id. at 33.
14

Follow-Up study (“GuLF STUDY”). 28

Chapter five presents Dr. Cook’s

conclusions on general causation for four categories of health conditions: (1)
respiratory conditions, (2) dermal conditions, (3) ocular conditions, and (4)
cancers. 29 Specifically, he reaches the following conclusions:
• Oil response and cleanup workers have reported acute
symptoms of coughing; shortness of breath; wheezing;
tightness in chest; and burning in nose, throat, and lungs.
Some individuals have prolonged effects from these
exposures, and can develop chronic respiratory conditions
. . . . These conditions include chronic rhinitis, chronic
sinusitis, allergic rhinitis, chronic obstructive pulmonary
disease (COPD), bronchitis, asthma or reactive airway
disease . . . . General causation analysis indicates that
these acute and chronic respiratory conditions can occur
in individuals exposed to crude oil, including weathered
crude oil, during oil spill response and cleanup work. 30
• Chemical irritation would be the most common problem
with workers, particularly for acute symptoms that occur
during or shortly after exposure. These can be described as
skin irritation, skin rash, or skin itching. Dermatitis may
also occur following exposure to chemicals, such as crude
oil, weathered crude oil, or dispersants. General causation
analysis indicates that these acute and chronic ocular
conditions can occur in individuals exposed to crude oil,
including weathered crude oil, during oil spill response
and cleanup work.31
• Chemical irritation would be the most common problem
with workers, particularly for acute symptoms . . . . These
can be described as acute eye burning, acute eye irritation,
28
29
30
31

Id. at 35-64.
Id. at 70.
Id. at 86-87 (emphasis added).
Id. at 92 (emphasis added).
15

and acute conjunctivitis. Chronic conditions following
exposure can occur in a smaller subset of individuals who
experience chronic inflammation affecting their eyes. The
evidence available at this time does indicate that exposure
to crude oil, including weathered crude oil, can result in
acute and chronic eye symptoms. The medical problems
most likely from these exposures are acute conjunctivitis,
chronic conjunctivitis, and dry eye disease. General
causation analysis indicates that these acute and chronic
ocular conditions can occur in individuals exposed to
crude oil, including weathered crude oil, during oil spill
response and cleanup work.32
Based on Dr. Cook’s report, defendants argue that Grant is unable to
prove general causation with relevant and reliable expert testimony. They
contend that Dr. Cook’s general causation report is unreliable because he
failed to: (1) verify Grant’s diagnoses; (2) follow the accepted methodology
for analyzing epidemiology and adequately evaluate the scientific literature;
and (3) identify the harmful level of exposure to any chemical that can cause
any of plaintiff’s alleged medical conditions. 33 Defendants further argue that
even if Dr. Cook’s report were reliable, it is unhelpful because it addresses
“few if any” of Grant’s medical complaints, and fails to specify what
particular toxins can cause which particular conditions. 34 Defendants also

32
33
34

Id. at 106 (emphasis added).
R. Doc. 44-1 at 9-17.
Id. at 12, 17-18.
16

note that two other sections of this Court have excluded Dr. Cook’s report for
similar reasons. 35
The Court first addresses defendants’ contention that Dr. Cook’s report
is unreliable and cannot establish general causation because it does not
identify a harmful level of exposure to a specific chemical.36 The Court
begins with this objection because “[s]cientific knowledge of the harmful
level of exposure to a chemical” is considered “a minimum fact[] necessary
to sustain the plaintiff’s burden in a toxic tort case.” Allen v. Pa. Eng’g Corp.,
102 F.3d 194, 199 (5th Cir. 1996). Accordingly, if the Court finds that plaintiff

35

36

Judge Lance Africk excluded an earlier version of Dr. Cook’s report.
See Novelozo v. BP Expl. & Prod., No. 13-1033, 2022 WL 1460103, at
*7 (E.D. La. May 9, 2022) and Murphy v. BP Expl. & Prod., No. 131031, 2022 WL 1460093 at *7 (E.D. La. May 9, 2022). And Judge Barry
Ashe excluded the same version of Dr. Cook’s report involved in this
case on the grounds that he failed “to identify the dose of the toxic
chemicals necessary to cause any of the complained-of health effects.”
Street, 2022 WL 1811144, at *6; see also Johns v. BP Expl. & Prod., No.
17-3304, 2022 WL 1811088 (E.D. La. June 2, 2022); Johnson v. BP
Expl. & Prod. Inc., No. 17-3308, 2022 WL 1811090 (E.D. La. June 2,
2022); Macon v. BP Expl. & Prod. Inc., No. 17-3548, 2022 WL 1811135
(E.D. La. June 2, 2022); Murray v. BP Expl. & Prod. Inc., No. 17-3582,
2022 WL 1811138 (E.D. La. June 2, 2022).
This Court also notes that it has excluded the same version of Dr.
Cook’s report in two other cases on the grounds that his opinion was
unreliable and unhelpful. See Dawkins v. BP Expl. & Prod., Inc., No.
17-3533, 2022 WL 2315846, at *8-9 (E.D. La. June 28, 2022); Coleman
v. BP Expl. & Prod., Inc., No. 17-4158, 2022 WL 2314400, at *8-9 (E.D.
La. June 28, 2022).
R. Doc. 44-1 at 15-17.
17

cannot “prove, at [a] minimum, that exposure to a certain level of a certain
substance for a certain period of time can cause a particular condition in the
general population,” then the Court’s inquiry into general causation is
complete.

Williams v. BP Expl. & Prod., Inc., No. 18-9753, 2019 WL

6615504, at *8 (E.D. La. Dec. 5, 2019) (citing Knight, 482 F.3d at 351); Lee
v. BP Expl. & Prod., Inc., No. 18-10381, 2020 WL 6106889, at *4 (E.D. La.
Sept. 29, 2020) (“[D]istrict courts within the Fifth Circuit have likewise
required toxic tort plaintiffs to define ‘the level of exposure necessary to
produce effects’ in order to establish general causation.”); see also Seaman
v. Seacor Marine L.L.C., 326 F. App’x 721, 726-27 (5th Cir. 2009) (per
curiam) (holding that “[w]ithout any facts that would establish the allegedly
harmful level of exposure . . . Dr. Prellop’s opinion regarding diesel exhaust
does not establish general causation”).
Here, the Court finds that Dr. Cook’s failure to identify the level of
exposure to a relevant chemical that can cause the conditions asserted in
plaintiff’s complaint renders his opinion unreliable, unhelpful, and incapable
of establishing general causation.
Turning first to reliability, Dr. Cook makes clear in his report that a
foundation of toxicology is that “dose determines the poison.” 37 Because of

37

R. Doc. 44-4 at 27 (Cook Report).
18

this maxim, Dr. Cook explains that “[t]oxicologists study chemicals for the
lowest levels that can cause adverse health effects . . . [which] requires
sophisticated studies that can control the low dose while accurately
measuring the effect of interest.” 38 Further, in his deposition, Dr. Cook
agreed that “without some quantitative understanding of the magnitude of
an individual’s exposure and the duration of time over which the exposure
occurred, it’s difficult to reach . . . meaningful conclusions about health
risks.”39
Dr. Cook also testified that he regularly consults the American Medical
Association’s (“AMA”) Guide to the Evaluation of Disease and Injury
Causation (“AMA Guide”). 40

The AMA Guide, attached to defendants’

motion, also emphasizes the importance of determining the dose-response
relationship. Specifically, the AMA Guide states that “the most critical phase
of the hazard evaluation process” is to “determine whether the estimated
dose was sufficient to explain observed clinical effects known to be associated
with the agent in question.”41 It additionally cautions that “[i]f exposureresponse

38
39
40
41

and

dose-response

considerations

Id.
R. Doc. 44-7 (Cook Deposition at 124:16-22).
Id. (Cook Deposition at 59:22-60:13).
R. Doc. 44-6 at 6-7.
19

are

disregarded,

then

misinterpretations,

misunderstandings,

erroneous

judgments,

and

inappropriate actions occur.”42
Despite the acknowledged importance of determining the doseresponse relationship, Dr. Cook’s report fails to identify what level of
exposure is necessary to be capable of producing the adverse health effects
that he analyzes. In his deposition, Dr. Cook testified as follows:
Q. If the legal test for general causation is that a review of
scientific and medical literature demonstrates that exposure to a
harmful level of a substance can cause a particular disease, have
you given us that opinion?
...
A. I did not quantify that, no.
...
Q. . . . [D]oes your report give a level of exposure to any substance
necessary to produce chronic rhinosinusitis?
A. No, it does not.
Q. Same question for chronic conjunctivitis?
A. No.
Q. For chronic rhinitis?
A. No.
Q. For chronic dry eye syndrome?
A. No. 43

42
43

Id. at 7.
R. Doc. 44-7 (Cook Deposition at 146:16-22, 148:8-21).
20

The closest Dr. Cook’s report comes to identifying a harmful level of exposure
is his consideration of the Bradford Hill factor of “dose-response.” But even
in the sections of his report that are dedicated to the dose-response
relationship and exposure, Dr. Cook still fails to identify a harmful dose of
any chemical to which Grant was allegedly exposed. Further, he fails to even
specify what constituent chemicals within “crude oil” and “weathered oil” he
is purportedly analyzing for a dose-response relationship. Instead, in the
“dose-response relationship” sections of his report, Dr. Cook simply cites
studies from both the Deepwater Horizon oil spill, as well as previous oil
spills, which generally found a positive association between respondents who
reported higher levels of exposure to crude oil and the prevalence of various
medical conditions. 44
For example, Dr. Cook’s “dose-response relationship” analysis on
rhinosinusitis states in full:
Kim et al. (2013) showed a dose-response by assigning residents
to zones based on their distance from the oil spill. The
researchers found a dose-response effect in all reported health
effects, including rhinitis. Rusiecki et al. (2022) also found a
dose-response by statistical analysis, with the responders who
had higher reported exposures having a higher incidence of
chronic sinusitis. 45

44
45

R. Doc. 44-4 at 74, 81-82, 89-90, 94 (Cook Report).
Id. at 74.
21

Notably, neither Dr. Cook, nor the two studies, specify a base level of
exposure that is necessary to cause rhinosinusitis. In the Kim, et al., study,
the respondents were “residents living in the Taean coastal area . . . [that]
had potential exposures to the oil spill from the Hebei Spirit tanker.” 46 Given
the ambiguity in whether residents were even exposed to oil, the study does
not specify what level of exposure it concludes is associated with
rhinosinusitis. And in the Rusiecki 2022 study, whether a participant was a
responder to the oil spill or not was used as a proxy for exposure, and “[o]ther
exposure assessments were not used to classify the responders as exposed.” 47
Again, any assessment of actual exposure, let alone the level of exposure to a
particular chemical, was not available. These studies, both of which are
“silent on the level of exposure . . . that would be significant,” do not assist
Dr. Cook in “meeting [Grant]’s ‘minimal burden of establishing by
‘[s]cientific knowledge . . . the harmful level of exposure to a chemical.’”
Seaman, 326 F. App’x at 727 (quoting Allen, 102 F.3d at 199).
Dr. Cook’s report does acknowledge that one of the limitations of the
studies he relies on is the “[l]imited availability of quantitative exposure
measures,” because of the “[l]ikely low [level of] individual exposures.” 48 For

46
47
48

Id. at 35 (emphasis added).
Id. at 47.
Id. at 57.
22

example, he notes that the GuLF STUDY researchers represented that it was
“difficult to obtain accurate and comprehensive exposure information on
participants . . . because many of the assessments would have been made
months after the workers were exposed,” and “many workers will have had
multiple exposures during the oil spill, . . . such that single exposure
measurements may not be sufficient to fully assess total exposure.” 49 The
report also mentions that the health hazard evaluations conducted by the
National Institute of Occupational Safety and Health “utilized primarily
qualitative assessment techniques rather than the traditional industrial
hygiene exposure assessment and quantitative measurement methods.” 50
Although Dr. Cook notes these limitations, he provides no explanation about
the “extent to which [these] limitations compromise [his] findings . . . about
causation.” Reference Manual at 553. Instead, Dr. Cook’s report appears to
conclude that there is some unspecified dose-response relationship for each
of the medical conditions that he analyzed for general causation.
In light of Dr. Cook’s failure to determine the relevant harmful level of
exposure, the Court finds that he lacks sufficient facts on both the
composition of the substances at issue and their toxicity to provide a reliable

49
50

Id. at 57-58.
Id. at 36.
23

opinion on general causation. See McGill v. BP Expl. & Produc., Inc., 830 F.
App’x 430, 433 (5th Cir. 2020) (per curiam) (upholding the exclusion of an
expert’s opinion that was “not based on sufficient facts” and relied on studies
that failed to “provide conclusive findings on what exposure level of Corexit
is hazardous to humans”); Moore, 151 F.3d at 277-78 (holding that the
“district court was entitled to conclude” that an expert’s opinion was
“inadequate under Daubert” when the expert “had no information on the
level of exposure necessary for a person to sustain the [relevant] injuries”).
The Court further notes that Dr. Cook’s lack of even an estimate of what level
of exposure is enough to be able to cause plaintiff’s alleged symptoms means
that he “lack[s] the scientific knowledge necessary to engage in the accepted
methodology employed by toxicologists to establish causation in a toxic tort
case.” Zellars v. NexTech Ne., LLC, 895 F. Supp. 2d 734, 741 (E.D. Va. 2012),
aff’d 533 F. App’x 192 (2013); see also McClain v. Metabolife Intern., Inc.,
401 F.3d 1233, 1241-42 (11th Cir. 2005) (noting that an expert who could not
provide an opinion on “the dose or level of exposure at which [the chemical]
causes harm” did “not follow the basic methodology that scientists use to
determine causation—the dose-response relationship”).
In sum, because Dr. Cook has not identified the harmful level of
exposure to the chemicals that Grant was allegedly exposed to that can cause
24

the conditions he alleges, Dr. Cook’s report is unreliable, lacks sufficient
factual support, and cannot establish general causation. See Seaman, 326 F.
App’x at 727 (“Without any facts that would establish the allegedly harmful
level of exposure, . . . Dr. Prellop’s opinion regarding diesel exhaust does not
establish general causation.”); Becnel v. BP Expl. & Prod., Inc., No. 17-1758,
2021 WL 4444723, *2-3 (M.D. La. Sept. 28, 2021) (“The Court finds that
without dose data, conclusions and opinions on causation are speculative
and unreliable.”).
In addition to finding Dr. Cook’s general causation analysis unreliable,
the Court also finds that Dr. Cook’s report is unhelpful to the factfinder for
many of the same reasons. Rule 702 requires that an expert’s opinion must
“help the trier of fact to understand the evidence or to determine a fact in
issue.” Fed. R. Evid. 702(a). “To be ‘helpful’ under Rule 702, the evidence
must possess validity when applied to the pertinent factual inquiry.” United
States v. Posado, 57 F.3d 428, 433 (5th Cir. 1995). Courts should thus
exclude testimony that “fail[s] to provide a ‘relevant’ link with the facts at
issue.” Knight, 482 F.3d at 355.
Here, the Court finds that Dr. Cook’s opinion is unhelpful because of
his inability to link any specific chemical that Grant was allegedly exposed
to, at the level to which he was exposed, to the conditions that he alleges in
25

his complaint. Specifically, Dr. Cook’s conclusion that there is a cause-andeffect relationship between the respiratory, ocular, and dermal conditions he
analyzed—only some of which are applicable to plaintiff51—and “expos[ure]
to crude oil, including weathered crude oil,” is unhelpful without identifying
the specific chemicals and exposure levels capable of causing specific
conditions. 52 As emphasized by another section of this Court, “Cook[’s
report] does not even identify any specific chemical or chemicals at issue”
and instead “refers generally to oil, dispersants, and volatile organic
compounds.” Street, 2022 WL 1811144, at *5. And as noted by plaintiff, he
retained Dr. Cook to provide a general causation report that “identifies the
medical conditions generally recognized in the literature on BP Oil Spill
responders,” not the specific conditions alleged by Grant. 53
This lack of specificity is concerning given that Dr. Cook testified that
there are “thousands of chemicals” in crude oil, and acknowledged that the

51

52
53

For example, although Dr. Cook found causation between exposure to
crude oil and chronic rhinitis, chronic sinusitis, allergic rhinitis,
chronic obstructive pulmonary disease, and asthma, plaintiff does not
purport to suffer from any of these conditions. See R. Doc. 56 at 8.
Moreover, many of plaintiff’s alleged conditions are not discussed in
Dr. Cook’s report. See, e.g., id. (noting the failure of Dr. Cook’s report
to address general causation as to the following symptoms alleged by
Grant: headaches, anxiety, impertigo, convulsions, seizures, and
cellulitis of lower extremity).
R. Doc. 44-4 at 87 (Cook Report).
R. Doc. 49 at 3.
26

different constituent chemicals in crude oil vary depending on location and
the impact of the “weathering process.” 54 In his testimony, Dr. Cook also
compared the study of health effects related to oil spills to previous studies
on lung cancer and cigarette smoke. He testified that like cigarette smoke,
there are “a lot of chemicals” in oil, and explained that although there are
“actually 6,000 known chemicals within tobacco smoke, . . . only a small
handful of those are recognized carcinogens.”55 Although Dr. Cook admits
that there are thousands of chemicals in crude oil, and that the chemical
composition of weathered oil is highly variable, he makes no attempt to
identify what chemicals within crude oil Grant was allegedly exposed to, or
what amounts of these chemicals can cause harm to humans. Indeed, the
majority of the studies he cites similarly do not identify what chemicals
respondents were exposed to, and one study noted a concern about
confounding variables, stating that some respondents likely had unknown
“petrochemical and other exposures not due to their oil spill cleanup
activities.”56 See Wagoner, 813 F. Supp. 2d at 802 (“It is true that in Joiner,
the Supreme Court indicated that an expert opinion on general causation

54
55
56

R. Doc. 44-7 (Cook Deposition 63:17-22, 104:21-105:1).
Id. (Cook Deposition at 63:1-17).
R. Doc. 44-4 at 57 (Cook Report).
27

should rely on studies that examine the specific agent that is at issue.” (citing
Joiner, 522 U.S. at 145-46)).
In providing a general causation determination, Dr. Cook had to assess
whether “the types of chemicals [that Grant] w[as] exposed to can cause [his]
particular injuries in the general population.” Knight, 482 F.3d at 355.
Given that Dr. Cook’s report does not identify what specific chemicals Grant
was exposed to, nor does it address many of the injuries Grant alleges, the
Court finds his report is unhelpful to the factfinder. See Knight, 482 F.3d at
355 (upholding the district court’s exclusion of an expert because the expert
relied on evidence that lacked “a ‘relevant’ link with the facts at issue”).
In reaching its decision, the Court rejects plaintiff’s efforts to defend
Dr. Cook’s failure to identify a harmful level of exposure to a specific
chemical. First, plaintiff asserts that Dr. Cook was unable to include data on
a harmful level of exposure because “BP consciously, or in the most favorable
light negligently, avoided recording data which would show the exposure
doses of spill response workers.” 57

57
58

Regardless of the veracity58 of this

R. Doc. 49 at 9.
Notably, other Courts addressing the scope of data collected as part of
the Deepwater Horizon oil spill have cast doubt on the assertion that
there is a lack of monitoring data associated with the spill. See, e.g., In
re Deepwater Horizon Belo Cases, No. 19-963, 2020 WL 6689212, at
*4 (N.D. Fla. Nov. 4, 2020), aff’d sub nom. In re Deepwater Horizon
BELO Cases, No. 20-14544, 2022 WL 104243 (11th Cir. Jan. 11, 2022)
28

assertion, Dr. Cook was not prevented from consulting the relevant scientific
and medical literature on the harmful effects of oil to determine whether a
relevant chemical has the capacity to cause the harm alleged by plaintiff in
the general population. Dr. Cook was not limited to data from the Deepwater
Horizon oil spill, and in fact did rely on studies from previous oil spills.59
Plaintiff additionally asserts that Dr. Cook’s reliance on studies that
used an “ever/never” binary exposure model in which respondents were
asked whether they had ever been exposed to crude oil, was an adequate
alternative to the traditional quantitative estimates of a dose-response
relationship.60 Specifically, plaintiff represents that because BP allegedly
“squandered the opportunity to preserve evidence of dose,” the scientific
community publishing “peer reviewed science for the BP Oil Spill worker
population,” has turned to qualitative measures, such as the “ever/never”

59
60

(finding that following the Deepwater Horizon oil spill Unified Area
Command (“UAC”), which was composed of several federal and state
agencies, “engaged in extensive and coordinated data collection and
environmental monitoring efforts, in what has been characterized as
‘the largest environmental investigation of an oil spill ever
undertaken’”); Harrison v. BP Expl. & Prod. Inc., No. 17-4346, 2022
WL 2390733, at *7 (E.D. La. July 1, 2022) (noting that Dr. Cook “could
have attempted to support an opinion as to the dose necessary to cause
plaintiff’s symptoms by relying on the universe of relevant
epidemiology and toxicology literature studying the spill or by relying
on the work of Dr. Jones”).
R. Doc. 44-4 at 33-35 (Cook Report).
R. Doc. 49 at 9.
29

model,

instead

of

the

“traditional

Bradford

Hill

dose-response

relationship.”61 Plaintiff thus asserts that because Dr. Cook is “simply using
the same methodology as the relevant scientific community” studying the BP
oil spill worker population, his general causation opinion should not be
excluded based on his failure to identify a particular chemical or dose. 62
Although the question of whether a study has been subjected to peer
review and publication is relevant, it is “not dispositive” or the “sine qua non
of admissibility.” Daubert, 509 U.S. at 592. And even if the ever/never
exposure model is used in some literature on the Deepwater Horizon oil
spill, Dr. Cook agreed at his deposition that “without some quantitative
understanding of the magnitude of an individual’s exposure and the duration
of time over which the exposure occurred, it’s difficult to reach . . .
meaningful conclusions about health risks.” 63 More critically, Dr. Cook
states in his report that researchers associated with the Deepwater Horizon
oil spill studies that he relies on also expressed concerns about the
“accur[acy] and comprehensive[ness]” of respondents’ qualitive exposure
responses. 64

61
62
63
64

For example, the report notes that NIOSH investigators

Id.
Id. at 13.
R. Doc. 44-8 (Cook Deposition at 124:16-22).
R. Doc. 44-4 at 57 (Cook Report) (noting that “GuLF STUDY
researchers also noted that it would be difficult to obtain accurate and
30

“disregarded the self-reports of the workers, determining that the workers’
self-reported exposures had not been likely.” 65 Moreover, as noted above,
Dr. Cook was not limited to studies on the Deepwater Horizon oil spill in
developing his general causation opinion.
Given the concerns about the accuracy of this model from both
plaintiff’s expert as well as the investigators themselves, the Court does not
find that, in this context, Dr. Cook’s conclusions were reliable, or that he is
otherwise excused from determining a harmful level of exposure.
Furthermore, consideration of the studies that Dr. Cook relies on does
nothing to cure the lack of “fit” between his report and the facts of this case,
specifically his failure to identify any chemical that is capable of causing any
of the conditions that Grant alleges in his complaint.
In sum, plaintiff, as the party offering the testimony of Dr. Cook, has
failed to meet his burden of establishing the reliability and relevance of Dr.
Cook’s report. Moore, 151 F.3d at 276. Given that Dr. Cook’s report is
unreliable and fails to provide the “minimal facts necessary” to establish
general causation in this case, see Allen, 102 F.3d at 199, the Court grants
defendants’ motion to exclude Dr. Cook’s testimony. See Seaman, 326 F.

65

comprehensive exposure information on participants in the GuLF
STUDY”).
Id. at 42.
31

App’x at 728 (upholding the district court’s exclusion of an expert’s
testimony that did “not come close to establishing either general or specific
causation” and “provide[d] no clue regarding what would be a harmful level
of Ferox exposure”).

III. MOTION FOR SUMMARY JUDGMENT
A.

Legal Standard

Summary judgment is warranted when “the movant shows that there
is no genuine dispute as to any material fact and the movant is entitled to
judgment as a matter of law.” Fed. R. Civ. P. 56(a); see also Celotex Corp. v.
Catrett, 477 U.S. 317, 322-23 (1986); Little v. Liquid Air Corp., 37 F.3d 1069,
1075 (5th Cir. 1994) (en banc) (per curiam). “When assessing whether a
dispute to any material fact exists, [the Court] consider[s] all of the evidence
in the record but refrain[s] from making credibility determinations or
weighing the evidence.” Delta & Pine Land Co. v. Nationwide Agribusiness
Ins., 530 F.3d 395, 398-99 (5th Cir. 2008). All reasonable inferences are
drawn in favor of the nonmoving party, but “unsupported allegations or
affidavits setting forth ‘ultimate or conclusory facts and conclusions of law’
are insufficient to either support or defeat a motion for summary judgment.”
Galindo v. Precision Am. Corp., 754 F.2d 1212, 1216 (5th Cir. 1985) (quoting
32

10A Charles Alan Wright & Arthur R. Miller, Federal Practice and Procedure
§ 2738 (2d ed. 1983)); see also Little, 37 F.3d at 1075. “No genuine dispute
of fact exists if the record taken as a whole could not lead a rational trier of
fact to find for the nonmoving party.” EEOC v. Simbaki, Ltd., 767 F.3d 475,
481 (5th Cir. 2014).
If the dispositive issue is one on which the moving party will bear the
burden of proof at trial, the moving party “must come forward with evidence
which would ‘entitle it to a directed verdict if the evidence went
uncontroverted at trial.’” Int’l Shortstop, Inc. v. Rally’s, Inc., 939 F.2d 1257,
1264-65 (5th Cir. 1991) (quoting Golden Rule Ins. v. Lease, 755 F. Supp. 948,
951 (D. Colo. 1991)). “[T]he nonmoving party can defeat the motion” by
either countering with evidence sufficient to demonstrate the “existence of a
genuine dispute of material fact,” or by “showing that the moving party’s
evidence is so sheer that it may not persuade the reasonable fact-finder to
return a verdict in favor of the moving party.” Id. at 1265.
If the dispositive issue is one on which the nonmoving party will bear
the burden of proof at trial, the moving party may satisfy its burden by
pointing out that the evidence in the record is insufficient with respect to an
essential element of the nonmoving party’s claim. See Celotex, 477 U.S. at
325.

The burden then shifts to the nonmoving party, who must, by
33

submitting or referring to evidence, set out specific facts showing that a
genuine issue exists. See id. at 324. The nonmovant may not rest upon the
pleadings, but must identify specific facts that establish a genuine issue for
resolution. See, e.g., id.; Little, 37 F.3d at 1075 (“Rule 56 ‘mandates the entry
of summary judgment, after adequate time for discovery and upon motion,
against a party who fails to make a showing sufficient to establish the
existence of an element essential to that party’s case, and on which that party
will bear the burden of proof at trial.’” (quoting Celotex, 477 U.S. at 322)).

B.

Discussion

In their motion for summary judgment, defendants contend that they
are entitled to summary judgment “on two independent bas[es]” because
plaintiff has cannot establish either general or specific causation. 66 Although
the parties dispute whether plaintiff is required to present admissible expert
testimony to establish specific causation, neither party contests that expert
testimony is necessary to establish general causation. 67 Here, the Court has

66
67

R. Doc. 45-1 at 2.
See R. Doc. 49 at 3 (asserting that “it is not legally necessary to provide
specific causation expert testimony on temporary pain and suffering . .
. [and] [a]t most, a general causation opinion is needed”); R. Doc. 45-1
at 9 (“Even though the plaintiff is advocating that he does not need
expert evidence of specific causation, he recognizes that expert
evidence of general causation is a necessity.”).
34

excluded testimony from plaintiff’s only expert offering an opinion on
general causation. Although plaintiff has also retained Dr. Rachel Jones as
an “exposure assessment expert,” 68 she does not provide a general causation
opinion, and notably does not provide the information or analysis that Dr.
Cook’s report lacks. Specifically, she does not identify a harmful level of
exposure to the chemicals that Grant was allegedly exposed to that can cause
the conditions he alleges. Although Dr. Jones summarizes reports that
measured the levels of a variety of toxic chemicals at different cleanup sites,69
she does not address the issue of causation. In other words, Dr. Jones’s
report does not identify the level of those toxins that is harmful and that can
be associated with the symptoms at issue here. And despite plaintiff’s
assertion that Dr. Cook’s “general causation opinion relies on” Dr. Jones’s
report, Dr. Cook’s report neither discusses Dr. Jones’s report nor cites it as a
reference.70
Because the Court excludes Dr. Cook’s opinion on general causation,
and plaintiff has produced no other admissible general causation evidence in
this case, the Court need not reach the question of specific causation. See
Knight, 482 F.3d at 352 (noting that if “the district court properly

68
69
70

R. Doc. 49 at 3.
R. Doc. 49-16 (Jones Report).
See R. Doc. 44-4 (Cook Report).
35

determined that [an expert’s] testimony regarding general causation was
inadmissible, . . . then there would be no need to consider . . . specific
causation”). Given that Grant cannot prove a necessary element of his claims
against defendants, his claims must be dismissed. See Williams, 2019 WL
6615504, at *11 (“When a plaintiff has no expert testimony to prove his
medical diagnosis or causation at trial, the plaintiff’s suit may be dismissed
at the summary judgment stage.”); see also McGill, 830 F. App’x at 434
(upholding the district court’s grant of summary judgment given that the
plaintiff did “not put forward any non-speculative evidence that Corexit and
oil exposure cause the types of illnesses he suffer[ed] from”). Accordingly,
the Court grants defendants’ motion for summary judgment.

36

IV.

CONCLUSION
For the foregoing reasons, the BP parties’ motion to exclude the

testimony of Dr. Cook is GRANTED. The Court also GRANTS the BP parties’
motion for summary judgment. Plaintiff’s claims are DISMISSED WITH
PREJUDICE.

6th day of July, 2022.
New Orleans, Louisiana, this _____
_____________________
SARAH S. VANCE
UNITED STATES DISTRICT JUDGE

37