United States Court of Appeals
                           FOR THE EIGHTH CIRCUIT
                                   ___________

                                   No. 07-3350
                                   ___________

Howard J. Polski; Sheryl L. Polski,     *
                                        *
             Appellants,                *
                                        * Appeal from the United States
      v.                                * District Court for the
                                        * District of Minnesota.
The Quigley Corporation,                *
                                        *
             Appellees.                 *
                                   ___________

                             Submitted: May 14, 2008
                                Filed: August 13, 2008
                                 ___________

Before WOLLMAN, MURPHY, and SMITH, Circuit Judges.
                         ___________

SMITH, Circuit Judge.

       Howard and Sheryl Polski (collectively "the Polskis") brought suit against the
Quigley Corporation ("Quigley"), alleging that they suffered severe and permanent
impairment of their senses of taste and smell due to their use of Cold-Eeze, a nasal
spray made and distributed by Quigley for the treatment of cold symptoms. The
district court1 granted Quigley's motion to exclude the opinion and testimony of the
Polskis' sole causation expert. The court then granted Quigley's motion for summary



      1
      The Honorable Patrick J. Schiltz, United States District Judge for the District
of Minnesota.
judgment. The Polskis appeal the court's decision excluding the expert testimony and
the resulting summary judgment. We affirm.

                                     I. Background
       Because we are reviewing a grant of summary judgment, we describe the facts
in the light most favorable to the Polskis, the nonmoving party. Hervey v. County of
Koochiching, 

, 715 (8th Cir. 2008). The Polskis, brother and sister, each
used Cold-Eeze, as directed,2 for several days in December 2003, to treat symptoms
associated with the common cold. The Polskis each experienced a burning sensation
in their nostrils and sneezing with each application of the spray. In mid-January 2004
they both realized that they had lost their sense of taste, after confiding to one another
over a meal that they could not taste the food. In April 2004, the Polskis visited an
otolaryngologist,3 who found no physical causes for their sensory loss.

        The Polskis filed suit against Quigley, asserting claims for fraud, negligence,
strict products liability, breach of express and implied warranties, and violations of
Minn. Stat. Ann. § 325F.69, alleging that the use of Cold-Eeze caused their sensory
loss. To prove that Cold-Eeze caused their impairments, which was essential for each


      2
       The directions on the Cold-Eeze packaging, in relevant part, stated:

      •      Prime the pump by pumping several times into a clean tissue until
             COLD-EEZE® Nasal Spray dispenses
      •      Before use, blow your nose to clean your nostrils
      •      Insert the tip of the pump approximately 1/8" into one nostril and
             hold the other nostril closed
      •      Spray once into each nostril and inhale through the nose slowly
             and deeply
      •      Repeat every 2–4 hours at least six (6) times per day
      •      Continue use for an additional 48 hours after symptoms subside.
      3
       An otolaryngologist is a doctor specializing in the diagnosis and treatment of
disorders of the ear, nose, and throat.

                                           -2-
of their claims, the Polskis offered the expert opinion of Dr. Bruce Jafek, M.D., a
professor of otolaryngology at the University of Colorado School of Medicine. Dr.
Jafek authored two reports in this case, one for each of the Polskis. In each report, Dr.
Jafek opined that: (1) Cold-Eeze, when used as directed, comes into contact with the
olfactory epithelium—the "smell tissue" located high inside the human nose; (2) the
active ingredient in Cold-Eeze, zinc gluconate, is toxic to the olfactory epithelium; (3)
Cold-Eeze, when used as directed, delivers a sufficient amount of zinc gluconate to
the olfactory epithelium to damage the sense of smell; (4) the damage that the zinc
gluconate in Cold-Eeze caused to the olfactory epithelium is permanent in some cases;
and (5) the zinc gluconate in Cold-Eeze, and not something else, such as a virus,
caused the Polskis to lose their sense of smell.

       Quigley conceded that Dr. Jafek was qualified as a nasal health expert, but
moved to exclude Dr. Jafek's testimony under Federal Rule of Evidence 702 and
Daubert v. Merrell Dow Pharm., Inc., 

(1993). In its motion, Quigley
argued that Dr. Jafek's opinion was not based upon scientifically reliable evidence or
testing but was merely an untested speculative theory. The district court agreed and
struck Dr. Jafek's expert testimony. The court concluded that Dr. Jafek's causation
opinion rested on the unproven premise that Cold-Eeze, when used as directed, comes
into contact with the olfactory epithelium in humans. Consequently, his opinions were
not sufficiently reliable to be admitted under Rule 702.

      Because all of the Polski's claims required proof of causation and their
causation evidence was based solely on Dr. Jafek's expert opinion, having concluded
that Dr. Jafek's opinion was inadmissible, the court granted Quigley's motion for
summary judgment. The Polskis now appeal, arguing that the district court erred in
precluding Dr. Jafek's expert opinion.




                                          -3-
                                   II. Discussion
       We review the district court's exclusion of expert testimony for an abuse of
discretion. Sappington v. Skyjack, Inc., 

, 448 (8th Cir. 2008). Federal
Rule of Evidence 702 provides:

      If 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.

       When faced with a proffer of expert scientific testimony, the trial court must
make "a preliminary assessment of whether the reasoning or methodology underlying
the testimony is scientifically valid and of whether that reasoning or methodology
properly can be applied to the facts in issue." 

–93.

      We recently explained Rule 702 and the Daubert standard, as follows:

             The admissibility of expert testimony is governed by Federal Rule
      of Evidence 702; under Rule 702 the trial judge acts as a "gatekeeper"
      screening evidence for relevance and reliability. 

, 

. "Rule 702 reflects an attempt to liberalize the rules
      governing the admission of expert testimony. The rule clearly is one of
      admissibility rather than exclusion." Lauzon v. Senco Prods., Inc., 

, 686 (8th Cir. 2001) (internal quotations and citations omitted).
      "The exclusion of an expert's opinion is proper only if it is so
      fundamentally unsupported that it can offer no assistance to the jury."
      Wood v. Minn. Mining & Mfg. Co., 

, 309 (8th Cir. 1997)
      (internal quotations and citation omitted).



                                           -4-
            A district court should apply a three-part test when screening
      testimony under Rule 702.

            First, evidence based on scientific, technical, or other
            specialized knowledge must be useful to the finder of fact
            in deciding the ultimate issue of fact. This is the basic rule
            of relevancy. Second, the proposed witness must be
            qualified to assist the finder of fact. Third, the proposed
            evidence must be reliable or trustworthy in an evidentiary
            sense, so that, if the finder of fact accepts it as true, it
            provides the assistance the finder of fact requires.

      

(internal citations and quotations omitted).

             In Daubert, the Supreme Court provided a non-exhaustive list of
      factors a district court should consider when performing its gatekeeper
      function, including,

            1) whether the theory or technique can be (and has been)
            tested; 2) whether the theory or technique has been
            subjected to peer review and publication; 3) the known or
            potential rate of error; and 4) whether the theory has been
            generally accepted.

      

.

             Subsequent cases have proposed additional factors, including,
      whether the expertise was developed for litigation or naturally flowed
      from the expert's research; whether the proposed expert ruled out other
      alternative explanations; and whether the proposed expert sufficiently
      connected the proposed testimony with the facts of the case. 

–49.




                                         -5-
       In this case, the Polskis contend that the district court abused its discretion in
excluding Dr. Jafek's expert testimony. They assert that the district court went beyond
its "gatekeeping" duty and invaded the province of the jury by weighing the parties'
disputed arguments of causation.

       Quigley did not contest Dr. Jafek's qualifications to be an expert of
otolaryngology, the anatomy of the nose, and the senses of taste and smell. Instead
they challenged Dr. Jafek's opinion that Quigley's product, when used as directed, puts
zinc gluconate on a person's olfactory epithelium. Based on his own knowledge and
expertise, his research, the research of others, and his observation that Cold-Eeze
delivers a straight line spray capable of traveling several feet, Dr. Jafek concluded that
the Polski's use of Cold-Eeze caused their sensory loss. Dr. Jafek opined that the spray
emitted from the Cold-Eeze bottle traveled into the nasal cavity and through the
straight passageway to the olfactory epithelium, resulting in the zinc ions in the spray
coming into direct contact with the olfactory epithelium of the user; Dr. Jafek's other
conclusions all rely on the validity of this premise. Albeit conceivable that Quigley's
spray bottle could expel some quantity of the medication the full distance in the nasal
passage to the olfactory epithelium, Dr. Jafek never tested this theory—nor did anyone
else.

       The district court concluded that this untested theory was "not sufficiently
reliable to be admitted under Rule 702." Polski v. Quigley Corp., No. 04-4199, 

, at *5 (D. Minn. Sept. 5, 2007). After a thorough review, we find no
abuse of discretion in the district court's decision to exclude Dr. Jafek's testimony.

       Dr. Jafek's causation theory is based on his untested belief that Cold-Eeze, when
used as directed, travels in a straight-line liquid movement capable of reaching the
olfactory epithelium through the nasal passage, allowing the zinc ions in the drug to




                                           -6-
come into contact with the difficult to access olfactory epithelium.4 The Polskis admit


      4
        The same scientific research that Dr. Jafek primarily relies upon for the
proposition that anosmia (the loss of smell) can result from zinc ions coming into
direct contact with the olfactory epithelium, reached its conclusion after conducting
an experiment in which a zinc-sulfate solution (not zinc-gluconate) was applied
directly to the olfactory epithelium by inserting a long, needle-like sprayer "upward
along the septum until definitely past the middle turbinate." Max M. Peet, Dean H.
Echols, Harry J. Richter, The Chemical Prophylaxis for Poliomyelitis: The Technic
of Applying Zinc Sulfate Intranasally, 108 JAMA 2184, 2186 (1937). An illustration
within this journal article depicts such a sprayer carefully inserted high into the nose.

explained:

      [I]n practically all instances the solution did not go above the middle
      turbinate if an ordinary atomizer was used with the tip of the spray
      introduced only slightly within the nostril. . . . It is evident that to be
      effective the spray must be directly applied to the olfactory area. We
      wish to especially emphasize this point. Ordinary spraying with the
      atomizer tip introduced below the middle turbinate will not suffice
      except in isolated instances.

Jafek's own earlier writings discuss the difficulty in accessing
the olfactory mucosa (epithelium) of the human nose:

      [O]lfactory mucosa is almost anatomically inaccessible in living humans.
      It is sheltered, for good reason, as it contains naked nerve endings in
      direct contact with the outside world, which proximally communicate
      with the brain. To reach it, the biopsy instrument must pass
      approximately 7 cm deep into the nostril, the terminal portion blindly,
      into a 1.0 mm crevasse between the adjacent nasal bones
      (septum/perpendicular plate and superior turbinate of ethmoid). Direct
      visualization with even the smallest telescope (Machida, 1.5 mm) with
      coordinated biopsy is impossible.

Bruce W. Jafek, Ultrastructure of Human Nasal Mucosa, 98 Laryngoscope 1576,

                                          -7-
that Dr. Jafek had not scientifically tested this theory. However, the Polskis assert that
such testing could not ethically be conducted on live humans because research has
shown that zinc may cause loss of smell and taste if it comes into contact with the
olfactory epithelium. As the district court observed, however, Dr. Jafek's theory could
have easily and ethically been tested by placing a substance with similar dispersal
qualities to Cold-Eeze but lacking zinc or any other potential toxin into a Cold-Eeze
bottle and administering the substance to participants as directed by Cold-Eeze's
instructions. Following such an experiment, participants could be examined to
determine whether the administered substance actually came into contact with the
olfactory epithelium.

       In short, we find no abuse of discretion in the district court's exclusion of Dr.
Jafek's testimony. Dr. Jafek's causation theory relied on an unproven and indeed
untested premise. The district court applied Rule 702 following Daubert's guidance,
noting that "because Dr. Jafek's theory has not been tested at all, it has never been
subjected to peer review and publication, nor has it been generally accepted in the
scientific community, nor does it have a known or potential rate of error." Polski,

, at *5. These are all valid considerations under Daubert.5


1576 (1983).
      5
       In Daubert, the Supreme Court stated:

      Ordinarily, a key question to be answered in determining whether a
      theory or technique is scientific knowledge that will assist the trier of
      fact will be whether it can be (and has been) tested. . . . Another pertinent
      consideration is whether the theory or technique has been subjected to
      peer review and publication. . . . Additionally, in the case of a particular
      scientific technique, the court ordinarily should consider the known or
      potential rate of error . . . . Finally, "general acceptance" can yet have a
      bearing on the inquiry.

–94.

                                           -8-
       The Polskis had the burden of establishing, by a preponderance of the evidence,
that Dr. Jafek's testimony was admissible under Rule 702. Marmo v. Tyson Fresh
Meats, Inc. 

, 757–58 (8th Cir. 2006) (citing 

–90). This required sufficient proof that Dr. Jafek's testimony was "the product of
reliable principles and methods," and that he "applied the principles and methods
reliably to the facts of the case." Fed. R. Evid. 702. The district court explained that
its decision "does not mean that Dr. Jafek's theory is necessarily wrong; it simply
means that the theory meets none of the indicia of reliability identified in Daubert and
therefore must be excluded." Polski, 

, at *5. The district court
concluded that Dr. Jafek's testimony was not sufficiently reliable and too speculative
to be presented to the jury. We do not consider this conclusion an abuse of discretion.6

      As all of Dr. Jafek's other opinions relating to causation relied on his untested
opinion that Cold-Eeze, when used as directed, comes into direct contact with the

      6
        We note that Dr. Jafek's theory of causation offered in this case has been
offered by plaintiffs in several other cases involving anosmia allegedly caused by the
use of Zicam, another nasally-inhaled cold remedy containing zinc gluconate; in each
of those cases, Dr. Jafek's testimony was excluded. See Lusch v. Matrixx Initiatives,
Inc., No. 05-292, 

(D. Or. Sept. 25, 2007) (granting defendant's
motions to exclude expert testimony and for summary judgment, ruling there was no
reasonable scientific evidence supporting Dr. Jafek's theory); O'Hanlon v. Matrixx
Initiatives, Inc., No. 04-10391, 

(C.D. Cal. Jan. 3, 2007); Benkwith
v. Matrixx Initiatives, Inc., 

(M.D. Ala. 2006) (same); Hans v.
Matrixx Initiatives, Inc., No. 04-540, 

at *8 (W.D. Ky. Sept. 29,
2006) (excluding Dr. Jafek's expert testimony regarding Zicam's causation of anosmia
because he "failed to show any of the steps which he says are necessary in order to
cause permanent anosmia in a human" and therefore his testimony regarding the cause
of plaintiff's anosmia "is unreliable and therefore inadmissible under Fed. R. Evid.
702"); Sutherland v. Matrixx Initiatives, Inc., No. 04-0129, slip op. at *4–5 (N.D. Ala.
Nov. 7, 2006) ("Despite this court's admiration for Dr. Jafek's professional
accomplishments, it concludes that the methods and procedures he employed are not
sufficiently reliable under Daubert and Rule 702 to allow him to share his opinions
with a jury").

                                          -9-
olfactory epithelium, the court excluded the remainder of Dr. Jafek's causation
testimony. 

Because the Polskis' claims required proof of causation and they
relied solely on Dr. Jafek's testimony to establish such causation, once that evidence
was excluded, the Polskis could not make a prima facie case. Thus, the district court's
grant of summary judgment in favor of Quigley was proper.

                                 III. Conclusion
      Accordingly, we affirm the judgment of the district court.
                     ______________________________




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