Case Title: Bowen v. E.I. DuPont

Citation: 

Docket Number: 580, 2005

State: delaware

Court: Delaware Supreme Court

Date: 2006-09-15T00:00:00Z

Document:
IN THE SUPREME COURT OF THE STATE OF DELAWARE 
MATTHEW BOWEN and MELISSA  
) 
ELLIS, as parents and natural guardians of )  No. 580, 2005 
EMILY BOWEN and MATTHEW 
 
) 
BOWEN and MELISSA ELLIS,  
 
)  Court Below:  Superior Court 
individually; and MARTIN GRIFFIN and 
)  of the State of Delaware in 
TRUDI GRIFFIN, as parents and natural 
)  and for New Castle County 
guardians of DARRIN GRIFFIN and   
) 
MARTIN and TRUDI GRIFFIN,  
 
)  C.A. No. 97C-06-194 
individually, 
 
 
 
 
 
) 
 
 
 
 
 
 
 
) 
 
 
Plaintiffs Below,  
 
) 
 
 
Appellants,  
 
 
) 
 
 
 
 
 
 
 
) 
v. 
 
 
 
 
 
 
) 
 
 
 
 
 
 
 
) 
E. I. DUPONT DE NEMOURS & CO., 
) 
INC.,  
 
 
 
 
 
) 
 
 
 
 
 
 
 
) 
 
 
Defendant Below,  
 
) 
 
 
Appellee. 
 
 
 
) 
 
Submitted:  July 12, 2006 
Decided:  September 15, 2006 
 
Before STEELE, Chief Justice, HOLLAND, BERGER, JACOBS, Justices, and 
STRINE, Vice Chancellor,* constituting the court en banc. 
 
 
Upon appeal from the Superior Court.  AFFIRMED. 
 
 
Thomas C. Crumplar, Jacobs & Crumplar, Wilmington, Delaware; Joel S. 
Perwin (argued) admitted pro hac vice for appellants. 
 
 
James W. Semple, Morris, James, Hitchens & Williams, LLP, Wilmington, 
Delaware for appellees. 
 
STEELE, Chief Justice: 
 
*Sitting by designation pursuant to Del. Const. Art. IV § 12. 
 
2
 
 
The plaintiffs-appellants, Bowen, et al.,1 appeal from the Superior Court’s 
Order excluding two of the plaintiffs’ experts’ opinions and the resulting grant of 
summary judgment in favor of the defendant-appellee, E. I. Du Pont de Nemours 
and Company, Inc.  The appellants claim that the trial judge abused his discretion 
by excluding their proffered experts’ opinions because: (1) the experts were 
sufficiently qualified through their personal study and experience to offer opinions 
in certain areas in which they lacked formal training; and (2) the experts’ 
methodologies underlying their opinions were verifiable and therefore reliable.  
We conclude that the trial judge did not abuse his discretion when he excluded the 
plaintiffs’ proffered expert opinions.  Accordingly, we affirm the Superior Court’s 
Order excluding the proffered expert testimony and granting summary judgment to 
the defendants.  
FACT AND PROCEDURAL BACKGROUND 
 
This appeal concerns two of eight personal injury actions that parents from 
England, Scotland, Wales, and New Zealand filed in 1997 on behalf of their minor 
                                                 
1 
Matthew Bowen and Melissa Ellis, as parents and natural guardians of Emily Bowen and 
Matthew Bowen and Melissa Ellis individually; and Martin Griffin and Trudi Griffin, as parents 
and natural guardians of Darren Griffin and Martin and Trudi Griffin, individually.  
 
 
3
children.2  The families allege that their exposure to Benlate, a chemical 
agricultural product that DuPont manufactured, caused the children to be born with 
birth defects.    
On August 18, 1997, DuPont moved to dismiss the all of the complaints on 
grounds of forum non conveniens.  The trial judge granted DuPont’s motion on 
August 28, 1998.  We reversed that judgment, on June 14, 1999, and remanded so 
the litigation could continue in Delaware.3  On July 24, 2001, DuPont filed a 
motion to dismiss all the actions as time barred.  The trial judge dismissed six of 
the eight actions on April 25, 2002.  The families appealed and we again reversed 
the trial judge’s dismissal.4   
On May 20, 2003, the plaintiffs moved to consolidate the cases for further 
proceedings.  The trial judge, on April 27, 2004, consolidated the cases for pretrial 
purposes, but refused to try all eight cases together.5  He ordered the cases to be 
                                                 
2  
The Bowen, Griffin, and Memon families are from England and Wales.  The Brown, 
Copeland and Johnstone families are from Scotland.  The Ison and Hanham families are from 
New Zealand. 
 
3  
See Ison, et al. v. E.I. DuPont De Nemours & Co., 729 A.2d 832 (Del. 1999) (holding 
that the existence of a more convenient forum alone was an insufficient ground for dismissal 
without a showing of overwhelming hardship to defendant). 
 
4  
See Brown, et al.  v. E.I. DuPont de Nemours & Co., 820 A.2d 362 (Del. 2003) (holding 
that the statute of limitations did not begin to run until the technology and/or knowledge was 
available to allow the plaintiffs to discover that their injuries, obvious from birth, were caused by 
the negligence of another). 
 
5  
Ison v. E.I. DuPont De Nemours & Co., 2004 Del. Super. LEXIS 129 (Del. Super. Ct. 
2004) 
 
4
grouped in four pairs, with each pair to be tried separately.  The trial judge 
scheduled the claims made by and on behalf of Emily Bowen and Darren Griffin to 
be tried first. Those claims are the subject of this appeal.6   
Between 1970 and 1995, DuPont produced and sold the fungicide, Benlate.  
The product’s active ingredient, benomyl, was designed to prevent and cure fungal 
infections in plants and crops.  Although Benlate was only available for 
commercial use in the United States, the fungicide was approved and sold for 
residential use in the appellants’ home country, the United Kingdom.   
During the early stages of their pregnancies, Melissa Ellis and Trudi Griffin 
were exposed to Benlate.  In 1993, Ellis came in contact with Benlate through her 
and her husband’s repeated use of the product in their indoor vegetable garden in 
Cardiff, Wales.  Ellis’ neck, arms, hands, legs, and feet were wetted both from the 
mist of a sprayer used to apply a Benlate dilution and from contact with the 
saturated vegetation.  Griffin claims only one exposure to Benlate:  she was 
covered by a Benlate mist when her father-in-law sprayed an apple tree and some 
vegetation in his garden in Norfolk, England. 
                                                                                                                                                             
 
6  
Their trial was initially scheduled to begin on October 12, 2004 and conclude on or 
before December 3, 2004.  The scheduling of the other three trials remains pending until the 
resolution of the Bowen/Griffin matters. See generally Bowen v. E. I. du Pont de Nemours & 
Co., 2005 Del. Super. LEXIS 239, *5-*7 (Del. Super. Ct. 2005) (recounting the procedural 
history in more detail). 
 
 
5
 
The appellants allege that their exposures to Benlate led to Emily’s and 
Darren’s birth defects.  Emily was born August 9, 1994 with several physical 
deformities and neurological defects.  Emily has microphthalmia7 and coloboma8 
bilaterally, and is visually disabled. Emily also suffers from heart, ear, and 
psychomotor developmental defects. Darren was born on November 23, 1995 with 
microphthalmia, cataract, and blindness of the right eye. DuPont’s pediatric 
ophthalmologist diagnosed Darren’s condition as Persistent Primary Hyperplastic 
Vitreous (PPHV). 
Although Emily’s consulting geneticist, Dr. Michael A. Patton, initially 
disagreed, DuPont maintained from the start of this litigation that Emily’s injuries 
and condition constituted CHARGE,9 a syndrome that is generally believed to be 
genetic, as opposed to environmental, in origin.10  Dr. Patton concluded in 2002, 
and maintained in 2003, that Emily did not meet the diagnostic criteria for 
                                                 
7  
Microphthalmia or microphthamos is defined as “a birth defect with abnormal smallness 
of one or both eyes.”  The Mosby Medical Encyclopedia, at 505 (revised ed. 1992). 
 
8  
Coloboma is defined as “a birth defect in which a cleft extends along the edge of the 
eyeball.  This affects the iris, ciliary body, or the blood vessel layer (choroid).”  Id. at 192. 
 
9  
CHARGE is an acronym for a syndrome consisting of Coloboma of the eye, Heart 
defects, Atresia of the choanae, Retardation or neural abnormalities, and Ear abnormalities. 
Bowen, 2005 Del. Super. LEXIS 239 at *13, n9.  
 
10  
Bowen, 2005 Del. Super. LEXIS 239 at *12-*13.  
 
 
6
CHARGE, but acknowledged that his opinion could change depending on her 
physical development and any developments in the science related to CHARGE.11   
 
In 2004, researchers published a study identifying a possible genetic cause 
of CHARGE.12  Those researchers believed that various deletions within the 
genetic code for the CHD713 protein inhibit gene expression, which in turn leads to 
the birth defects constituting CHARGE.  After testing ordered by the Superior 
Court,14 two separate genetic laboratories confirmed that Emily has a CHD7 
mutation.15     
 
Given the results of the genetic testing and changes in the diagnostic criteria 
for CHARGE, Dr. Patton now believes that Emily has CHARGE.  He also believes 
that Emily’s CHD7 mutation was a substantial cause of her birth defects and her 
current condition.  Dr. Patton acknowledges, however, that he is not qualified to 
                                                 
11  
Id. at *14.  
 
12  
The study (hereinafter “the Vissers study”) was first presented in the medical journal 
"Nature Genetics." Vissers, L., Brunner, H., et. al., Mutations in a New Member of the 
Chromodomain Gene Family Cause CHARGE Syndrome, Nature Genetics 36(9): 955, 2004. 
 
13  
CHD7 refers to a chromodomain helicase DNA-binding protein, which is involved in 
unzipping a cell’s DNA allowing for gene expression and DNA replication. 
 
14  
On July 12, 2004 DuPont moved for the Superior Court to order the genetic testing.  The 
trial judge granted the motion on October 15, 2004, and allowed further discovery and 
supplementation of the expert reports.  Trial was rescheduled for May 9, 2005.  See Bowen, 2005 
Del. Super. LEXIS 239 at *18-*19.   
 
15  
See Id.  Darren Griffin’s genetic test results were negative for CHD7. 
 
 
7
rule out any environmental factors, such as Benlate, as a possible cause of Emily’s 
condition.16 
 
Dr. Charles V. Howard, in contrast, maintains that his expertise in 
teratology17 and toxicology18 qualifies him to opine that Benlate is a cause of 
Emily’s condition.  Dr. Howard is a medical doctor and lecturer at the University 
of Liverpool in Liverpool, England, where he received his medical training from 
1965 to 1970. He teaches courses in anatomy, microscopy and morphology.  Dr. 
Howard belongs to several professional organizations, including the British 
Society of Toxicological Pathologists and the Society for Developmental 
Pathology.19  
 
When he formulated his original opinion that Benlate caused Emily’s birth 
defects, Dr. Howard relied partially on Dr. Patton’s preliminary conclusion that 
Emily did not have CHARGE.  Dr. Howard also relied upon his education, 
training, research regarding Benlate, and the finding of Dr. MacIntosh with regard 
to the amount of Benlate that was dermally absorbed by Ellis.  Despite earlier 
                                                 
16  
See Id. at *20-21. 
 
17  
Teratology is defined as “the study of the causes and effects of inborn malformations and 
developmental abnormalities.”  The Mosby Medical Encyclopedia, at 754.   
 
18  
Toxicology is defined as “the scientific study of poisons, their detection, their effects, and 
methods of treatment for conditions they produce.” Id.  at 779. 
 
19  
Bowen, 2005 Del. Super. LEXIS 239 at *15.  
 
 
8
acknowledging that he might need to alter his opinion if Dr. Patton’s genetic 
assessment of Emily changed, Dr. Howard currently adheres to his opinion that 
Benlate is “a” cause of Emily’s condition.  Dr. Howard similarly concluded that 
Benlate caused Darren’s birth defects.20 
The appellants chose Dr. David L. MacIntosh to provide an opinion that 
calculates the pregnant mothers’ dermal exposure to Benlate as well as the amount 
of Benlate that would have been absorbed into the mothers’ bloodstreams.  Dr. 
MacIntosh professed to be a dermal exposure expert, but concedes that he has only 
a working knowledge about dermal absorption.  Dr. MacIntosh received both his 
undergraduate degree in Decisional Science, in 1988, and his master's degree in 
Environmental Science, in 1991, from Indiana University. He received his 
doctorate in Environmental Health in 1995, from the Harvard School of Public 
Health.  Between 1996 and 2002, Dr. MacIntosh taught graduate and 
undergraduate courses in environmental chemical air quality and hazardous waste 
management at the University of Georgia; and in 2002, he became a senior 
associate with Environmental Health and Engineering, Inc., in Newton, 
Massachusetts.21 
                                                 
20  
 See Bowen, 2005 Del. Super. LEXIS 239 at *16-17. 
 
21  
Bowen, 2005 Del. Super. LEXIS 239 at*10-*11. 
 
 
9
Dr. MacIntosh has acted as a consultant with the EPA and the 
World Health Organization.  He has presented papers and speeches on 
topics relating to human exposure to environmental contaminants, and 
has regularly published articles in peer reviewed scientific journals 
discussing human exposure to pesticides in residential settings.  His 
research has included human exposure to chemical hazards in 
community and occupational settings.22 
 
Relying solely upon a model formula provided by the EPA in its publication 
entitled “Dermal Exposure Assessment Principles and Applications,”23 Dr. 
MacIntosh calculated the amount of Benlate that would have been absorbed 
through the skin of the pregnant mothers.  He based his inputs for the EPA’s 
formula upon the mothers’ testimony regarding their exposures to Benlate and on 
several assumptions he derived therefrom.24  In choosing the EPA model and in 
formulating his opinion in general, Dr. MacIntosh did not consider any existing 
studies concerning the dermal absorption of Benlate, including a study 
commissioned by the appellants in 2000.  The record is not clear why the 
appellants chose to provide Dr. MacIntosh with these studies well after he had 
                                                 
22  
Id. at *11.  
 
23  
Dermal Exposure Assessment: Principles and Applications, Exposure Assessment Group, 
Office of Health and Envtl. Assessment, U.S. Envtl. Protection Agency, Interim Report, 
EPA/600/8-91/011B, January 1992, referring to, Potts RO, Guy RH. Predicting Skin 
Permeability, 
Pharm. 
Res., 
9(5):663-669, 
1992, 
available 
at 
http://www.epa.gov/ncea/pdfs/derexp.pdf  (cited in Bowen, 2005 Del. Super LEXIS 239 at *19, 
n8.) 
 
24  
See Bowen, 2005 Del. Super. LEXIS 239 at*12. 
 
 
10
already formulated his opinion, and even then, only the week before he was 
deposed. 
 
On April 11, 2005, DuPont filed several supplemental motions based upon 
the recent genetic test results and the expert opinions filed in response by the 
plaintiffs' expert witnesses.  Relying upon D.R.E. 702, Daubert v. Merrell Dow 
Pharmaceuticals, Inc.,25 and its Delaware progeny,26 Dupont moved to exclude 
parts of Dr. Patton’s testimony.  On similar grounds, DuPont also renewed a March 
23, 2003 motion to exclude the testimony of Drs. Howard, Randall L. Tackett,27 
MacIntosh, Mitchell W. Sauerhoff,28 and Robert F. Smith29.  The trial judge 
granted DuPont’s motions concerning Drs. Patton, MacIntosh, and Howard.30  
 
The trial judge limited Dr. Patton’s testimony on the grounds of relevance 
and competency because of Dr. Patton’s admitted lack of expertise in teratology 
                                                 
25  
509 U.S. 579 (1993). 
 
26  
See e.g., Nelson v. State, 628 A.2d 69 (Del. 1993); M.G. Bancorporation v. LeBeau, 737 
A.2d 513 (Del. 1999). 
 
27  
Dr. Tackett, as an expert in pharmacology, was to provide testimony regarding the 
properties of Benlate as a human teratogen and its effects on fetal development at differing levels 
of exposure.   
 
28  
Dr. Sauerhoff, having been retained as an expert in over three hundred cases relating to 
the causal effect of substances, along with evaluating the methodology of opposing experts, was 
to testify that Drs. Howard, Tackett and MacIntosh followed standard methodologies accepted in 
their respective disciplines in rendering their opinions. 
 
29  
The trial judge explained that, for reasons about which he was unaware, the plaintiffs 
withdrew Dr. Smith as an expert witness. Bowen, 2005 Del. Super. LEXIS 239 at *17, n17.  
 
30  
Bowen, 2005 Del. Super. LEXIS 239 at * 23.  
 
 
11
and toxicology.31  He excluded Dr. MacIntosh’s opinion regarding dermal 
absorption (1) because Dr. MacIntosh was not a qualified dermal absorption expert 
and (2) because the methodology Dr. MacIntosh used to reach his conclusions was 
not reliable.32  Because Dr. Howard relied upon Dr. MacIntosh’s testimony to 
establish that Benlate was dermally absorbed and transferred to the fetuses, the trial 
judge excluded Dr. Howard’s testimony concerning the teratogenic effects of 
Benlate on Emily Bowen and Darren Griffin.33  The trial judge also excluded Dr. 
Howard’s testimony regarding a possible interaction between Benlate and Emily 
Bowen’s CHD7 mutation on the grounds that that opinion concerned genetics, and 
Dr.Howard was not a qualified geneticist.34   
 
Because the plaintiffs necessarily relied on the testimony of Drs. Patton, 
MacIntosh, and Howard to establish that Benlate is a human teratogen and a 
specific cause of the plaintiffs’ injuries, the trial judge granted DuPont’s motion for 
summary judgment.  The appellants now ask this Court to reverse the evidentiary 
rulings and the resulting grant of summary judgment.  After briefing and oral 
                                                 
31  
Id. at *23-24. 
 
32  
Id. at *24. 
 
33  
Id. at *24-*25. 
 
34  
Id. at *24. 
 
 
12
argument before a panel on May 24, 2006, we requested supplemental 
memoranda35 and held en Banc oral arguments on July 12, 2006. We now affirm. 
DISCUSSION 
 
The appellants argue that the trial judge abused his discretion by excluding 
the testimony of Drs. Howard and MacIntosh, and consequentially entering 
summary judgment in DuPont’s favor on the assumption that the appellants could 
not go forward without that testimony.  Appellants contend that the trial judge 
focused too narrowly upon the experts’ formal specialties and training, as opposed 
to their personal study and experience when he analyzed the experts’ 
qualifications.  The appellants also claim that their experts’ methodologies were 
reliable and that any alleged flaws in their methods should have been left for the 
jury to weigh.  We conclude that the trial judge did not abuse his discretion by 
excluding Dr. MacIntosh’s testimony. Because Dr. Howard necessarily relied upon 
Dr. MacIntosh’s testimony to establish that Benlate was dermally absorbed and 
reached the fetuses, we need not address the trial judge’s decision to exclude Dr. 
Howard’s specific theories regarding Benlate. 
                                                 
35  
The appellants’ supplemental memorandum was required to identify the scientific 
studies, cited within the record, which they relied upon as the basis for the expert opinions that: 
(1) Benlate causes birth defects; (2) a CHD7 gene mutation is a cause of CHARGE, but it is not 
the sole cause of that birth defect; and (3) Benlate, acting in conjunction with the mutated gene, 
is a concurrent cause of CHARGE.  The appellants were also asked to determine on which of the 
three listed opinions Dr. Howard is qualified to render an opinion.  In response, the appellee’s 
supplemental memorandum was required to concede or dispute the scientific reliability of each 
of the studies listed in the appellants’ supplemental memorandum and identify the rationale or 
basis for any dispute.   
 
13
 
Delaware Rule of Evidence 702 governs the admission of expert testimony.  
That rule provides:  
 [i]f scientific, technical or other specialized knowledge will assist the 
trier of fact to understand the evidence or to determine a fact in issue, 
a witness qualified as an expert by knowledge, skill, experience, 
training or education may testify thereto in the form of an opinion or 
otherwise, if (1) the testimony is based upon sufficient facts or data, 
(2) the testimony is the product of reliable principles and methods, 
and (3) the witness has applied the principles and methods reliably to 
the facts of the case.  
 
D.R.E. 702 is substantially similar to Federal Rule of Evidence 702, which the 
United States Supreme Court interpreted in Daubert v. Merrell Dow 
Pharmaceuticals, Inc.36  Daubert specifically addressed the admissibility of 
scientific testimony under F.R.E. 702.  In Kumho Tire Co., Ltd. v. Carmichael,37 
the Court extended the Daubert holdings to apply to all expert testimony 
concerning "scientific, technical or other specialized" matters.  Though the United 
States Supreme Court’s interpretations of F.R.E. 702 in Daubert and Kumho are 
only binding upon federal courts, this Court has expressly adopted their holdings as 
correct interpretations of D.R.E. 702.38   
                                                 
36  
509 U.S. 579 (1993) (“Daubert”). 
 
37  
526 U.S. 137 (1999). 
 
38  
M.G. Bancorporation v. Le Beau, 737 A.2d 513, 521 (Del. 1999). 
 
 
14
 
Accordingly, D.R.E. 702 “imposes a special obligation upon a trial judge to 
‘ensure that any and all scientific testimony...is not only relevant, but reliable.’”39  
The trial judge acts as the “gatekeeper” in deciding whether an expert's testimony 
“has a reliable basis in the knowledge and experience of [the relevant] 
discipline.”40  The foci of a Daubert analysis are the “principles and methodology” 
used in formulating an expert’s testimony, not on the expert’s resultant 
conclusions.41  To help determine whether an expert’s “principles and 
methodology” are rooted in science and derived from the scientific method,42 the 
Daubert Court identified several factors that may be useful to a trial judge acting 
as the “gatekeeper:” 
(1) whether a theory or technique has been tested;  
 
(2) whether it has been subjected to peer review and publication;  
  
(3) whether a technique had a high known or potential rate of error 
and whether there are standards controlling its operation; and 
  
(4) whether the theory or technique enjoys general acceptance within 
a relevant scientific community.43  
 
                                                 
39  
Id. (quoting Daubert, 509 U.S. at 589). 
 
40  
Id. at 523. 
 
41  
Daubert, 509 U.S. at 595. 
 
42  
Id. at 590. 
 
43  
Id. at 590-94. 
 
 
15
These factors identified in Daubert are not a “definitive checklist or test.”44  
Rather, the “inquiry must be ‘tied to the facts’ of a particular ‘case,’”45 because 
“the factors identified in Daubert may or may not be pertinent in assessing 
reliability, depending on the nature of the issue, the expert's particular expertise, 
and the subject of his testimony.”46 
Consistent with Daubert, we apply a five-step test to determine the 
admissibility of scientific or technical expert testimony.  The trial judge must 
determine whether: 
(1) the witness is qualified as an expert by knowledge, skill 
experience, training or education;  
 
(2) the evidence is relevant;  
 
(3) the expert's opinion is based upon information reasonably relied 
upon by experts in the particular field;  
 
(4) the expert testimony will assist the trier of fact to understand the 
evidence or to determine a fact in issue; and 
  
(5) the expert testimony will not create unfair prejudice or confuse or 
mislead the jury.47 
 
                                                 
44  
See Kumho, 526 U.S. at 150 (quoting Daubert, 509 U.S. at 593).  
 
45  
See Id. (quoting Daubert, 509 U.S. at 591). 
 
46  
See Id. (quoting the Solicitor General from the Brief for United States as Amicus Curiae).  
 
47  
Tolson v. State, 900 A.2d 639, 645 (Del. 2006); Eskin v. Carden, 842 A.2d 1222, 1227 
(Del. 2004). 
 
 
16
The party seeking to introduce the expert testimony bears the burden of 
establishing its admissibility by a preponderance of the evidence.48 
We review a trial judge’s decision to exclude expert testimony for abuse of 
discretion.49  “This deferential standard of review is simply a recognition that trial 
judges perform an important gatekeeping function and, thus, ‘must have 
considerable leeway in deciding in a particular case how to go about determining 
whether particular expert testimony is reliable.’”50   
Although a motion to exclude expert testimony is frequently case 
dispositive, a deferential abuse of discretion standard of review is congruent with 
the trial judge’s prescribed role as “gatekeeper.”51   
We find that the trial judge did not abuse his discretion when he decided to 
exclude Dr. MacIntosh’s testimony.  A review of the record establishes that the 
trial judge, as gatekeeper, appropriately excluded Dr. MacIntosh’s opinion 
                                                 
48  
Minner v. Am. Mortgage & Guar. Co., 791 A.2d 826, 843 (Del. Super. Ct. 2000) (citing 
Nat'l Bank of Commerce v. Dow Chem. Co., 965 F.Supp. 1490, 1497 (D. Ark. 1996), aff'd 133 
F.3d 1132 (8th Cir. 1998)); See also Oddi v. Ford Motor Co., 234 F.3d 136, 145 (3d Cir. 2000); 
Cook v. Sheriff of Monroe County, 402 F.3d 1092, 1107 (11th Cir. 2005); Marmo v. Tyson Fresh 
Meats, 2006 U.S. App. LEXIS 19609, *14 (8th Cir. 2006); Nelson v. Tennessee Gas Pipeline 
Co., 243 F.3d 244, 251 (6th Cir. 2001); Daubert v. Merrell Dow Pharms., 509 U.S. 579, 592, 
n10 (U.S. 1993). 
 
49  
Le Beau, 737 A.2d at 522 (citing General Electric Co. v. Joiner, 522 U.S. 136, 141-42 
(1997)). 
 
50  
Garden v. State, 815 A.2d 327, 338 (Del. 2003) (quoting Kumho, 526 U.S. at 152). 
 
51  
See, e.g., Lust by & Through Lust v. Merrell Dow Pharms., 89 F.3d 594, 597 (9th Cir. 
1996); Rosen v. Ciba-Geigy Corp., 78 F.3d 316, 318 (7th Cir. 1996). 
 
 
17
concerning dermal absorption.  Dr. MacIntosh is not qualified to offer a dermal 
absorption opinion.  Even assuming arguendo that Dr. MacIntosh is qualified, his 
testimony is not admissible because his underlying methodology is not reliable.   
The appellants argue that the trial judge determined Dr. MacIntosh’s 
qualifications in an overly restrictive manner.  They suggest that Dr. MacIntosh is 
an exposure expert and does not profess to be an absorption expert.  The appellants 
also dispute the trial judge’s finding that Dr. MacIntosh “provided expert 
testimony in the field of absorption.”  Rather, the appellants claim that Dr. 
MacIntosh mechanically applied the Potts-Guy model, a methodology that they 
claim he is qualified to employ. 
 
Dr. MacIntosh, however, did more than simply plug inputs into a model.  
Moreover, his alleged “working knowledge” of dermal absorption did not qualify 
him even to choose the Potts-Guy model.   While we recognize that at times an 
expert may be qualified by criteria outside of his formal training or designated 
specialty,52 we must scrutinize an expert’s qualifications with “due regard for the 
                                                 
52  
See, e.g., Caro v. Woodford, 280 F.3d 1247 (9th Cir. 2002), cert. denied, 536 U.S. 951 
(2002) (allowing a toxicologist with expertise in pesticide toxicology to testify regarding a 
criminal defendant’s brain damage);  McCullock v. H.B. Fuller Co., 61 F.3d 1038 (2d Cir. 1995) 
(holding a clinician’s extensive experience sufficient to permit him to opine that the plaintiff’s 
medical condition was caused by exposure to a toxin); Hopkins v. Dow Corning Corp., 33 F.3d 
1116 (9th Cir. 1994) (finding a toxicologist, although not a medical doctor, to be qualified to 
testify regarding causal connection between breast implant and plaintiff’s disease).  
 
 
18
specialization of modern science.”53  Dr. MacIntosh’s use of the Potts-Guy model  
raised questions that only a dermal absorption expert would be qualified to answer.  
The trial judge noted, and Dr. MacIntosh admitted, that the Potts-Guy model is the 
least favored method of measuring dermal absorption.  In fact, the EPA guidelines 
recommend this model be used only when no comparable human studies exist.54   
Dr. MacIntosh does not have the requisite qualifications, formal or 
otherwise, to opine why it was appropriate to choose the least favored, as opposed 
to other, methods of measuring dermal absorption.  Nor is Dr. MacIntosh qualified 
to opine about any of the alleged flaws with the Potts-Guy model.  It is apparent 
from the record that Dr. MacIntosh’s utilization of the Potts-Guy model is “not cut 
and dried,” and that only a dermal absorption expert would be qualified to answer 
the questions surrounding the adequacy and choice of the Potts-Guy model.55  Dr. 
MacIntosh may not be permitted to “hide behind” the allegedly reliable Potts-Guy 
model and be relieved from having to defend its applicability.56  Therefore, we find 
                                                 
53  
Dura Auto. Sys. of Ind., Inc. v. CTS Corp., 285 F.3d 609, 614 (7th Cir. 2002). 
 
54  
“[W]hen chemical specific data are unavailable…[t]his method should be used in the 
absence of actual field data.” Standard Operating Procedures for Residential Exposure 
Assessments, EPA Scientific Advisory Panel (SAP) September 1997 Meeting.  “The 
uncertainties associated with this assessment stem from the use of an assumed permeability 
coefficient.”  Id.    
 
55  
Dura Auto.., 285 F.3d at 614.  
 
56  
Id. (“A scientist, however well credentialed he may be, is not permitted to be the 
mouthpiece of a scientist in a different specialty. That would not be responsible science. A 
theoretical economist, however able, would not be allowed to testify to the findings of an 
 
19
that the trial judge reasonably concluded that Dr. MacIntosh is not qualified to 
offer an opinion concerning dermal absorption.   
We also conclude the trial judge did not abuse his discretion by finding that 
Dr. MacIntosh’s methodology was unreliable.  Dr. MacIntosh’s exclusive reliance 
on the Potts-Guy model and his ignorance of existing studies measuring human 
dermal absorption of Benlate is disconcerting.57  Despite the EPA guidelines’ 
recommendation that the Potts-Guy model only be used when there are no 
comparable human studies, Dr. MacIntosh failed to inquire about any existing 
studies58 before reaching his conclusion.59  Even more troubling is the failure of 
plaintiffs’ counsel’s to provide Dr. MacIntosh with actual existing studies known 
                                                                                                                                                             
econometric study conducted by another economist if he lacked expertise in econometrics and 
the study raised questions that only an econometrician could answer.  If it were apparent that the 
study was not cut and dried, the author would have to testify; he could not hide behind the 
theoretician.”). 
 
57  
See Hamilton County Emergency Communs. Dist. v. Orbacom Communs. Integrator 
Corp., 2005 U.S. Dist. LEXIS 21639, 17 (D. Tenn. 2005) (finding it significant that an expert 
“relied exclusively upon information and interpretations provided by [the party that hired him as 
an expert]” and conducted nothing more than “the most cursory of investigations into the 
reliability of many of the sources upon which he relied for benchmark data.”).    
 
58  
See In re Rezulin Prods. Liab. Litig., 2004 U.S. Dist. LEXIS 3104 (D.N.Y. 2004) 
(holding “the dispositive fact” to be that the expert  ignored “directly relevant scientific data in 
violation of [recognized] standards.”).   
 
59  
See Claar v. Burlington N. R.R., 29 F.3d 499, 502-03 (9th Cir. 1994) (“In order to qualify 
as scientific knowledge, an inference must be derived by the scientific method. Coming to a firm 
conclusion first and then doing research to support it is the antithesis of this method.”) (internal 
citations omitted). 
 
 
20
to them, especially the “TNO Study”60 which plaintiffs’ counsel themselves 
commissioned for the Benlate related litigation of Bourne v. Dupont.61  Given the 
limitations in the EPA guidelines for using the Potts-Guy model, Dr. MacIntosh’s 
failure to consider the existing human dermal absorption studies was clearly a 
failure to employ “the same level of intellectual rigor that characterizes the practice 
of an expert in the relevant field.”62    
The appellants contend that, even if “better” studies exist for calculating the 
dermal absorption rate of Benlate, the Potts-Guy model is, nonetheless, a peer-
reviewed, published, and widely accepted methodology.  The issue, however, is 
not whether the Potts-Guy model is ever a reliable tool.63  Rather, the issue is the 
methodology that underlies how to determine to rely exclusively upon the Potts-
Guy model and to ignore or discard “more favorable” methodologies.  Conceivably 
a scenario will arise where a qualified dermal absorption expert, after considering 
                                                 
60  
W.J.A. Meuling, R. Engel, A.A. Vink, L. Roza, Dermal Absorption of Benlate WP50 in 
Human Volunteers, TNO Voeding, Netherlands Organization for Applied Science (May 25, 
2000). 
 
61  
189 F. Supp. 2d 482 (D. W. Va. 2002), aff'd 85 Fed. Appx. 964, 2004 WL 117634 (4th 
Cir. W. Va. 2004). 
 
62  
Kumho, 526 U.S. at 152. 
 
63  
Cf. United States v. DICO, Inc., 266 F.3d 864, 870 (8th Cir. 2001) (finding an expert’s 
use of a model “passes scrutiny under Daubert” because the model “is sanctioned by the EPA 
and is considered a standard model that is acceptable and commonly used by [experts in the 
relevant field].” (emphasis added)).  Utilizing the Potts-Guy model without first considering 
available human studies is neither standard nor common. 
 
 
21
comparable human studies as recommended by the EPA guidelines, will employ 
the Potts-Guy model.  In such a scenario, the appellants would be correct in 
arguing that any potential flaws of experts choice of the Potts-Guy model would 
affect the weight given to it by the jury and not its admissibility.   
But that scenario did not occur in this case.  Dr. MacIntosh’s failure to 
follow the recognized EPA guidelines for using the Potts-Guy model, due to his 
own ignorance of the existing human studies and the complicity of the plaintiffs’ 
counsel, directly undermines the reliability of his methodology.   
D.R.E. 702 requires that a proffered expert opinion be “the product of 
reliable principles and methods” reliably applied to the facts of each case. Here, the 
record supports the trial judge’s conclusion that Dr. MacIntosh was not qualified to 
give a dermal absorption opinion and that the opinion he did proffer was not the 
product of a reliable methodology. For those reasons, we conclude that the trial 
judge did not abuse his discretion when he excluded Dr. MacIntosh’s opinion. 
Because Dr. MacIntosh’s opinion is critical to establishing Dr. Howard’s 
contentions that Benlate specifically caused the children’s birth defects, we need 
not reach or address the issue of Dr. Howard’s qualifications or methodology.64  
 
                                                 
64  
We decline to address the appellant’s argument that the trial judge abused his discretion 
by excluding evidence about governmental studies and warnings. The appellants specifically 
“request[ed] the Court, if it reverses the Superior Court’s orders and Judgment, to address this 
issue, in order to avoid the necessity of a retrial.” Opening Br. pg 32. Because we are not 
reversing the Superior Court’s order, we decline to address this issue.  
 
22
CONCLUSION 
 
 
For the foregoing reasons, the judgment of the Superior Court is affirmed.