MEMORANDUM AND ORDER

STEVEN GOLD, Magistrate Judge

Introduction

Plaintiff, Rhonda Zwillinger, brings this action against defendants, Garfield Slope Housing Corp. ("Garfield Slope"), Bobby's Twins Contracting Corp. ("Bobby's Twins"), Amoco Chemical Corp. ("Amoco"), E.I. Du Pont De Nemours and Co. ("Du Pont"), and Wellco Carpet Corp. ("Wellco Carpet"), to recover for injuries she claims to have suffered in October 1991, when new carpeting was installed in the hallway outside her apartment at 162 Garfield Place, Brooklyn, New York. In her complaint, plaintiff alleges that defendants were negligent, that the carpet was defective and unreasonably dangerous, and that the manufacture and installation of the carpet constituted ultrahazardous activities. Pursuant to 28 U.S.C. § 636, the parties have consented to the assignment of this case to the undersigned magistrate judge for all purposes. See Docket Entry 60.

Defendants Amoco and Wellco Carpet now move for summary judgment, contending that the expert testimony upon which plaintiff relies to establish essential elements of her claims should be held inadmissible pursuant to Federal Rules of Evidence 702 and 703. Defendants further contend that they are entitled to summary judgment under New York law, arguing that a manufacturer is not liable to a plaintiff who suffers an idiosyncratic reaction to a product.

This Court scheduled an evidentiary hearing for March 2, 1998, at which plaintiff's expert would have been permitted to testify and plaintiff would have been afforded the opportunity to argue in support of the admissibility of her expert's opinions at trial. See Docket Entry 85. However, by letter dated February 23, 1998, plaintiff withdrew her request for an evidentiary hearing and asked that the Court decide the pending motion on the papers submitted by the parties. See Letter from Stewart D. Fried to the Honorable Steven M. Gold, Docket Entry 86.

This Court has carefully reviewed the parties' lengthy submissions. For the following reasons, defendants' motion for summary judgment is granted.

Facts

In October 1991, defendant Garfield Slope, the residential management and maintenance corporation at the apartment building where plaintiff then resided, undertook an asbestos abatement project. The project included the installation of a carpet in the first floor hallway. Compl. ¶¶ 7, 13; Zwill. Tr. 43-44. Before the carpet was laid, plywood flooring was placed in the hallway to cover linoleum tiles that had been found to contain asbestos. Zwill. Tr. 44-45, 89-90. Plaintiff, then a member of the co-op board, claims that she objected to the installation of the carpet because she had previously felt ill upon exposure to freshly laid carpet in a neighborhood video store. Zwill. Tr. 72-74, 86. However, despite plaintiff's objections, the carpet was installed in October 1991 by defendant Bobby's Twins. Compl. ¶ 8; Zwill Tr. 91. Plaintiff alleges that the carpet was manufactured, sold and distributed by defendants Amoco and Wellco Carpet. Compl. ¶¶ 9, 11.

Plaintiff complains that she began to experience burning skin and blurred vision within twelve hours of the installation of the carpet. Zwill. Tr. 95-96. Within twenty-four hours of the installation, plaintiff began to feel dizzy and to experience nausea, vomiting, bladder problems, and bowel problems. Zwill. Tr. 97-100. Over the next three weeks, plaintiff claims to have experienced a "spreading effect," meaning that things other than the carpet, such as art magazines, water colors, her gas stove, or perfume, began to cause her to feel the same symptoms. Zwill. Tr. 104-05. For example, plaintiff claims to have experienced symptoms in the subway when painting was being done or when disinfectant had recently been used; in the supermarket; around a friend who used ordinary detergent to wash her clothes; around shampoo, soap, or deodorant; around a lawn that had been sprayed with pesticide; and in public buildings such as museums. Zwill. Tr. 155. Additionally, plaintiff claims that exposure to chemicals caused her to feel depressed and extremely fatigued. Zwill. Tr. 158.

Plaintiff attributes her symptoms to chemical fumes, particularly "4-PC," which "off-gassed" from the carpet and which she then inhaled. Compl. ¶¶ 6-11. Plaintiff claims that her exposure to the carpet caused her to develop injuries including, but not limited to, immunotoxicity syndrome, which she also refers to as multiple chemical sensitivity ("MCS"). Compl. ¶¶ 2, 7-11, 16.

Approximately three weeks after the carpet was installed, plaintiff left her apartment and moved in with a friend in Brooklyn. She later went to stay with her mother. Zwill. Tr. 106-07. Around Thanksgiving of 1991, the co-op removed the carpet from the hallway and plaintiff was able to return to her apartment. Zwill. Tr. 109. However, plaintiff claims that she "[n]ow . . . had a full-blown case of multiple chemical sensitivity" and continued to experience the symptoms described above. Zwill. Tr. 143-44.

In March 1993, plaintiff left Brooklyn and moved to upstate New York for a month, where she resided with a friend in what she describes as a "safe house;" that is, a house which is specially designed for people who suffer from MCS. Plaintiff subsequently moved to Tucson, Arizona and resided in another specially designed house, later moving to a porcelain trailer where she resided for eight months. Plaintiff now lives in a special chemical-free house which she had built in Paulden, Arizona. Zwill. Tr. 7-9.

After moving to Arizona, plaintiff consulted with Dr. Michael Gray, plaintiff's proposed expert witness in this case. Dr. Gray met with plaintiff on one occasion in July 1993 and subsequently authored letter reports detailing his expert opinions regarding her condition.

Plaintiff filed her complaint in this action in New York Supreme Court, Kings County on July 11, 1994. Defendant Wellco Carpet removed this action to federal court in August, 1994, and defendants DuPont, Amoco, and Garfield Slope subsequently answered the complaint. See Docket Entries 1, 5, 10, 15. The parties entered into a Case Management Order on August 9, 1995, which divided discovery into two phases. See Docket Entry 22; Case Management Order (Def. Amoco's Supp. Reply Br. in Supp. of Mot. for Summ. J. ("Amoco Reply Br."), Ex. B). Phase I discovery was limited to "discovery on plaintiff's claim that she was exposed to `toxic substances' released from the carpeting . . . and that a particular chemical substance[s], at the concentration and duration of exposure as demonstrated by plaintiff was the proximate cause of plaintiff's alleged injuries." Id. at 2. Phase II was described as "the summary judgment phase on the issues of plaintiff's exposure and causation as set forth in Phase I." Id. In accordance with the Case Management Order, defendants Amoco Chemical Corp. and Wellco Carpet Corp. now move for summary judgment.

Discussion I. Summary Judgment

It is well-settled that a party seeking summary judgment must establish that there is no genuine issue of material fact in dispute and that the moving party is therefore entitled to judgment as a matter of law. See Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 256, 106 S. Ct. 2505, 2514, 91 L.Ed.2d 202 (1986); Thompson v. Gjivoje, 896 F.2d 716, 720 (2d Cir 1990). Further, "the inferences to be drawn from the underlying facts . . . must be viewed in the light most favorable to the party opposing the motion." Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 587, 106 S. Ct. 1348, 1356, 89 L.Ed.2d 538 (1986) (quoting United States v. Diebold, Inc., 369 U.S. 654, 655, 82 S. Ct. 993, 994, 8 L.Ed.2d 176 (1962)).

If the moving party discharges its burden of proof under Rule 56(c), "[t]he non-moving party has the burden of coming forward with `specific facts showing that there is a genuine issue for trial.'" Phillips v. Kidder, Peabody Co., 782 F. Supp. 854, 858 (S.D.N.Y. 1991) (quoting Fed.R.Civ.P. 56(e)). Moreover, "Rule 56(e) . . . provides that a party opposing a properly supported motion for summary judgment may not rest upon mere allegations or denials of his pleading." Anderson, 477 U.S. at 256. Rather, to defeat a properly supported motion for summary judgment, the non-movant must make an affirmative showing of sufficient evidence that would enable a jury to return a verdict in the non-movant's favor. Id. at 249. In deciding a motion for summary judgment, "the trial court's task . . . is carefully limited to discerning whether there are any genuine issues of material fact to be tried, not to deciding them." Quarantino v. Tiffany Co., 71 F.3d 58, 65 (2d Cir. 1995) (quoting Gallo v. Prudential Residential Servs., Ltd. Partnership, 22 F.3d 1219, 1223 (2d Cir. 1994)).

As noted above, plaintiff claims that her exposure to defendants' carpeting caused her to develop immunotoxicity syndrome, or MCS. Compl. ¶¶ 2, 16. Plaintiff Zwillinger bears the burden of establishing at trial that the carpet in question in fact proximately caused her to suffer from this illness. See, e.g., In re Brooklyn Navy Yard Asbestos Litigation, 971 F.2d 831 (2d Cir. 1992). Plaintiff must prove both general causation — that is, that the product in question was capable of causing the symptoms of which she complains — as well as specific causation — that is, that the product did in fact cause plaintiff's symptoms.See Mancuso v. Consolidated Edison Co. of New York, Inc., 967 F. Supp. 1437, 1445 (S.D.N.Y. 1997); In re Agent Orange Product Liability Litig., 570 F. Supp. 693, 695 (E.D.N.Y. 1983); Federal Judicial Center, Reference Manual on Scientific Evidence 167 (1994). Defendants contend that plaintiff has failed to come forward with admissible evidence establishing that she was exposed to 4-PC, or any other chemical, emitted by the carpet in issue, or that this exposure caused her to become highly sensitive to a wide range of generally safe substances.

Plaintiff intends to rely upon the testimony of her expert witness, Dr. Michael Gray, to meet her burden of proving that gasses emitted by defendants' carpeting caused her to develop immunotoxicity syndrome or MCS. Defendants contend that Dr. Gray's testimony fails to meet the applicable standards governing the admissibility of expert testimony. Thus, defendants' motion for summary judgment is in essence a motion in limine seeking to preclude Dr. Gray from testifying at trial.

II. Admissibility of Plaintiff's Expert Testimony

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.

Fed.R.Evid. 702. As the language of the rule suggests, a court must ensure that two basic prerequisites are satisfied before allowing a party to present expert testimony at trial. First, the witness must be properly qualified as an expert to testify on scientific, technical, or specialized matters. See Stagl v. Delta Air Lines, Inc., 117 F.3d 76, 81 (2d Cir. 1997). Second, the expert must offer testimony that will assist the trier of fact to understand the evidence or to determine a fact in issue.See United States v. 31-33 York Street, 930 F.2d 139, 141 (2d Cir. 1991) (excluding expert testimony that would only complicate, rather than assist, the jury's decision "on a simple question for which the jury needed no help").

Defendants assert that Dr. Gray lacks the necessary qualifications to render an expert opinion concerning plaintiff's claimed illness. Defendants further contend that Dr. Gray's proposed testimony should be precluded at trial because it fails to meet the criteria of reliability and relevance set forth by the Supreme Court in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 113 S.Ct. 2786 (1993).

A. Dr. Gray's Expert Opinion

Dr. Gray's expert opinion concerning plaintiff Zwillinger's illness and its causes has been put before the court in three separate forms. First, Dr. Gray has authored three opinion letters, one undated, one dated December 10, 1993, and a third dated April 1, 1996. See Defs.' Ex. J, NN. Second, defendants have submitted the deposition of Dr. Gray, taken over six days in July and August of 1996. See Gray Tr. (Defs.' Ex. I). Finally, Dr. Gray has submitted an affidavit, dated October 20, 1997, in opposition to defendants' motion for summary judgment. See Aff. of Michael R. Gray ("Gray Aff.") (Pl.'s Response in Opp. To Mot. For Summ. J., Ex. B).

1. Diagnostic Steps Taken by Dr. Gray

Dr. Gray first met with plaintiff on July 13, 1993, approximately twenty-one months after plaintiff was exposed to the carpet in issue. See Gray Aff. ¶ 15; Gray Tr. 45. At that time, Dr. Gray took plaintiff's medical history. Zwillinger described for Gray the symptoms she experienced, both at the time the carpet was installed in the hallway of her apartment building, and following the installation. Dr. Gray also asked plaintiff to complete a "Comprehensive Medical History questionnaire," and a questionnaire relating to environmental exposure. See Gray Aff. ¶ 15.

Dr. Gray also performed a physical examination of plaintiff. As Gray concedes, the physical examination did not reveal anything of significance to plaintiff's exposure to 4-PC or the symptoms she complains of in this case. Id.; see also Gray Tr. 59-60; Defs.' Ex. NN at 6. At the conclusion of the visit, Dr. Gray noted that plaintiff's history was consistent with histories related by other individuals claiming to have been exposed to organic compounds of low molecular weight. See Gray Tr. 64.

In July 1993, Dr. Gray received a copy of plaintiff's medical records from Dr. Morton Teich. Gray Tr. 15-18, 33-35, 55. According to Gray, he also reviewed the results of laboratory tests ordered by other physicians plaintiff had seen, but did not review the medical records of any of plaintiff's prior physicians other than those of Dr. Teich. Gray Aff. ¶ 15; Gray Tr. 55. Gray himself ordered additional laboratory testing to determine the status and function of plaintiff's immune system, "consistent with the testing that [he] obtained in other cases involving exposure to highly reactive, low molecular weight organic compounds occurring individually or in combination." Gray Aff. ¶ 15; see also Gray Aff. ¶¶ 12-13 (describing testing done on other patients). Finally, Dr. Gray reviewed the results of laboratory tests which he contends confirm that the carpeting installed in the hallway of plaintiff's home in fact contained 4-PC. See Gray Tr. 116-17; Defs.' Ex. NN at 7.

2. Dr. Gray's Conclusions

Dr. Gray's conclusions, set forth in greater detail below, are summarized in his expert report. According to Dr. Gray, Rhonda Zwillinger has become "chemically sensitive" to a variety of substances, "including pesticides, organic solvents, formaldehyde, perfumes and other vapors which are commonly encountered." Zwillinger's extreme sensitivity to these common, generally safe, chemicals was caused, according to Gray, by her "exposures . . . to the outgassing vapors of 4PC from new carpets." As a result, when exposed to these common chemicals, Zwillinger now experiences a variety of symptoms including, but not limited to, palpitations, sweating, blurred vision, depression, dizziness, fatigue, numbness, and digestive problems. See Undated Letter at 1 (Defs.' Ex. J).

In his affidavit, Dr. Gray explains his diagnosis that Zwillinger suffers from "immunotoxicity syndrome" and "toxic encephalopathy." Gray defines immune toxicity as "an over activated immune system," or "the adverse effects of an unsuitable immune response caused by the direct or indirect action of a xenobiotic. It may also result from an immunologically mediated host response to a xenobiotic, its metabolites, or host antigens altered by these substances." Gray Aff. ¶¶ 21-22 (quoting Bradford O. Brooks and John B. Sullivan, Jr., Immunotoxicology in Hazardous Materials Toxicology: Clinical Principles of Environmental Health 192-93 (Pl.'s Ex. D3)). He defines toxic encephalopathy as "the manifestation of confusion, spaciness, dizziness, inability to concentrate, difficulty with word finding, short-term memory loss, disorientation." Gray Tr. 122-23. Dr. Gray concludes that Zwillinger's immune toxicity and toxic encephalopathy resulted from plaintiff's "exposure to, and the toxic effects of, the haptogenic, reactive, organic compounds," specifically 4-PC, emitted by defendants' carpet. See Gray Aff. ¶¶ 22, 39. According to Gray, his conclusion that exposure to 4-PC vapors caused plaintiff's condition is based upon "the temporal relationship between the installation of the carpet, the onset of [plaintiff's] symptoms, the continuation of her symptoms, and the subsequent laboratory findings in July of '93 and January of '94, and the overall clinical picture." Gray Tr. 119.

In his affidavit, Dr. Gray sets forth the basis for his conclusion that Zwillinger's immune system is "over activated." Gray contends that the immune system tests he performed revealed an excess of T lymphocytes and autoimmune antibodies in plaintiff's system. See Gray Aff. ¶ 22. More specifically, Gray states that the tests revealed measurable, elevated levels of "specific anti-trimellitic anhydride, anti-formaldehyde, and anti-isocyanate antibody titers in her serum, all of which relate to compounds known to be emitted from new synthetic carpet." Gray Aff. ¶ 39. In other words, Rhonda Zwillinger has antibodies for latex, isocyanate, formaldehyde, and trimellitic anhydride in her system. See Gray Tr. 234. According to Dr. Gray, the presence of these antibodies demonstrates that Rhonda Zwillinger has an over-activated immune system as a result of exposure to volatile organic compounds, or VOCs. See Gray Aff. ¶ 39.

Dr. Gray's affidavit goes on to describe the mechanism by which an immune system becomes over-activated. According to Dr. Gray, receptor site proteins reside in cell membranes throughout the body. See Gray Aff. ¶ 24. These receptor site proteins react when stimulated by specific carbon-based or organic compounds that come in close contact with the proteins, resulting in the production of enzymes. See id. The particular carbon-based skeletal structure of the stimulating compound determines whether the receptor site protein will react See id. at ¶¶ 24-25. When a receptor site protein is stimulated, the cell is then "activated." The activated cell produces a large volume of antibodies, begins to multiply rapidly and clone "daughter cells," and attacks the stimulating compound. See id. at ¶¶ 26-27. Simultaneously, the activated cell sends out "chemical messengers (called cytokines)" to digest the stimulating compound. See id. at ¶ 28. These cytokines may produce symptoms such as "fevers, chills, sweats, fatigue, headaches, muscle aches, joint pains, and general malaise," Id. at ¶ 29.

Dr. Gray states that the "first line of defense" against most toxins is generally the collection of enzymes concentrated in the cells lining the gastrointestinal tract, the lining of the lungs, and the liver (the cytochrome P-450 enzyme system). See id. at ¶ 30. Therefore, according to Dr. Gray, an individual exposed for a prolonged period of time to toxins, even at low concentrations, may develop immune system problems, because if the level of toxin builds up in the system it can penetrate beyond the "first line of defense" (the gastrointestinal tract, lung lining, and liver) and circulate throughout the body by attaching itself to "carrier" proteins, See id. at ¶¶ 31-32. In particular, Dr. Gray claims that organic compounds, known as "haptens," are capable of forming strong chemical bonds with these "carrier" proteins. See id. at ¶ 33. According to Dr. Gray, 4-PC is such a hapten.

Dr. Gray has used manual light microscopic cell counts and automated flowcytometer cell counts to determine that a number of his patients, including Rhonda Zwillinger, have activated immune systems. Dr. Gray decided to test these patients based upon their reported symptoms, which are similar to those described by plaintiff. Gray asserts that his subject population demonstrates a level of immune system activity that is more than twice the expected level. See Aff. at ¶¶ 37, 38. Dr. Gray contends that each of his patients has developed an over-active immune system as a result of exposure to, and the toxic effects of, haptogenic compounds such as 4-PC. See id. at ¶¶ 39, 41. He claims that this hyper-activation of the immune system has resulted in the development of opportunistic infections in his patients, including "abnormal gut flora, recurrent upper respiratory infections, higher than expected occurrence of vaginitis, and an increased prevalence of active viral infections caused by members of the herpes viral group." See id. at ¶ 40. He blames the increased presence of infection on the fact that the patients' bodies are devoting "immunologic energy and resources" to fighting chemical antigens, rather than toward keeping "normal flora in proper balance." See id.

Dr. Gray theorizes that, once a patient has become "sensitized" by one hapten, other haptens may produce similar symptoms. Thus, according to Gray, Zwillinger's exposure to 4-PC has rendered her "chemically sensitive" to a wide variety of chemicals encountered in everyday modern life. See Undated Letter at 1 (Defs.' Ex. J).

B. Dr. Gray's Qualifications as an Expert Witness

A trial judge has broad discretion in determining whether a witness is qualified to testify as an expert. See McCullock v. H.B. Fuller Co., 61 F.3d 1038, 1042 (2d Cir. 1995);McGregor-Doniger Inc. v. Drizzle Inc., 599 F.2d 1126, 1138 n. 7 (2d Cir. 1979); see also In re Paoli R.R. Yard PCB Litig., 35 F.3d 717, 741 (3d Cir. 1995); United States v. Brown, 776 F.2d 397, 400 (2d Cir. 1985) (noting that "[t]he words `qualified as an expert by knowledge, skill, experience, training, or education' must be read in light of the liberalizing purpose of the Rule"). A determination of whether a proposed expert is qualified to testify involves a two-step inquiry: First, the court "should determine whether the proffered expert has minimal educational or experiential qualifications in a field that is relevant to a subject which will assist the trier of fact," second, the court "should further compare the expert's area of expertise with the particular opinion the expert seeks to offer [and permit t]he expert . . . to testify only if the expert's particular expertise, however acquired, enables the expert to give an opinion that is capable of assisting the trier of fact." Federal Judicial Center, Reference Manual on Scientific Evidence 55-56 (1994).

Defendants contend that Dr. Gray is not qualified to offer an expert opinion in this case because he is not trained or certified in immunology or toxicology. See Defs.' Mem. of Law at 27. Cf. Federal Judicial Center, Reference Manual on Scientific Evidence 197 (1994) (noting that, in a toxic tort case, "[a] proposed expert should be able to demonstrate an understanding of the discipline of toxicology, including statistics, toxicological research methods, and disease processes."). However, although "physician[s] without particular training or experience in toxicology [are] unlikely to have sufficient background to evaluate the strengths and weaknesses of toxicological research," some physicians who are occupational health specialists or who are certified in medical toxicology may be qualified as experts in toxic tort cases. See id. at 197-98.

Dr. Gray is Board Certified in Occupational Medicine and is a Certified Independent Medical Examiner. Further, he states that he has received post-graduate training in toxicology, both as part of his Occupational Medicine Residency, and as part of the course work required for his Masters in Public Health and his Diploma in Industrial Health. See Gray Aff. ¶¶ 1-2. Therefore, Dr. Gray appears to possess the minimum educational qualifications necessary to render an expert opinion in this case. See In re Paoli, 35 F.3d at 741 (holding that exclusion is improper simply because an expert does not have the most specifically appropriate degree or training).

Other indicia of expertise in toxicology include the following: (1) whether the proposed expert has published articles in peer-reviewed journals; (2) whether the proposed expert has competed successfully for research grants; (3) whether the proposed expert has been selected to serve on advisory panels; and (4) whether the proposed expert holds a faculty appointment in toxicology, risk assessment, or a related field See Reference Manual on Scientific Evidence at 199-200.

Dr. Gray has served as the Director of Occupational Medicine at the Arizona Center for Occupational Safety and Health, as Chairman of the Department of Occupational Medicine at Kino Community Hospital in Tucson, Arizona, and as Chief of Staff of the local hospital in Benson, Arizona. He has taught internal medicine at the University of Arizona. See Gray Aff. ¶¶ 2-3. Additionally, Dr. Gray received a fellowship that led to completion of training for a Diploma in Industrial Health at the University of London, School of Hygiene and Tropical Diseases.See id. at ¶ 6. As part of that program, Dr. Gray completed a number of Health Hazard Evaluations involving exposure of workers and members of the public to volatile organic solvents and other organic compounds. See id.

Dr. Gray estimates that occupational and environmental medicine represents approximately 11 to 13 percent of his annual revenue.See id. at ¶ 9. Moreover, in the past ten years, he claims to have examined almost two hundred patients who complain of symptoms similar to those complained of by plaintiff, and who have experienced significant exposures to "one or more highly reactive, low molecular weight (1000), organic, carbon based compounds, including but not limited to solvents, aldehydes, phenols, petroleum distillates, polyaromatic hydrocarbons, pesticides, etc." Id. at ¶ 10. Dr. Gray is in the process of completing a descriptive epidemiology of eighty-nine of these patients, which he plans to publish in the Archives of Environmental Health. See id. at ¶ 12.

In Mancuso v. Consolidated Edison Co. of New York, Inc., 967 F. Supp. 1437 (S.D.N.Y. 1997), the district court excluded the testimony of plaintiff's expert in a case involving exposure to PCBs where the proposed expert — an internist — was unable to answer critical questions regarding PCBs. The court noted that the expert's deposition testimony "revealed that he had no clear idea what levels of PCB contamination would be dangerous to humans." Id. at 1444. Similarly, in Cuevas v. E.I. DuPont De Nemours and Co., 956 F. Supp. 1306 (S.D. Miss. 1997), the district court excluded the testimony of plaintiff's proposed expert after it found that the doctor had no knowledge of the herbicide in issue or of the toxicological effects that the herbicide could produce. See id. at 1307. Further, the court in Cuevas found it relevant that the doctor had not conducted any studies on the herbicide and could cite no tests or publications demonstrating that exposure to the herbicide could cause the types of problems experienced by plaintiff. See id. Additionally, the Cuevas court noted that the doctor did not know the level of exposure experienced by plaintiff or the specific contents of the herbicide mixture to which plaintiff was exposed. See id. at 1308.

As discussed in greater detail below, Dr. Gray clearly has limited knowledge of the specific effects of 4-PC on humans. For example, when asked at his deposition to identify studies linking 4-PC to disorders of the immune system, or to state the level of 4-PC which triggers a toxic effect in humans, Gray was unable to do so. See e.g. Gray Tr. 217-18. However, the case against the expert's qualifications in Mancuso was stronger than defendants' argument in this case with respect to Gray. In contrast to Gray, the proposed expert in Mancuso was an internist who had never before been qualified as an expert in an environmental case, was not a toxicologist and had treated patients exposed to PCBs only twice. Further, the doctor had no training in environmental medicine, occupational medicine or PCBs, had given no lectures or seminars on the subject, and had written no articles on toxicology, environmental diseases or toxins. Additionally, in Mancuso, "plaintiffs' lawyer had to give [the expert] books to acquaint him with the possible health effects of PCBs and did so after [the expert] had reached his conclusions." Mancuso, 967 F. Supp. at 1442. In this case, Dr. Gray is Board Certified in occupational medicine, has undertaken post-graduate study involving toxicology, and claims to have significant experience examining patients who have been exposed to various organic compounds of similar molecular weight to 4-PC.

The Second Circuit has construed expert qualification requirements liberally. See McCullock, 61 F.3d at 1038. InMcCullock, the court admitted the testimony of one of plaintiff's proposed experts, an engineer, despite that expert's lack of knowledge of the constituents of the glue fumes in issue and his lack of formal academic training in fume dispersal and air quality. The court concluded that these factors went to the weight and credibility of his testimony, not its admissibility. See 61 F.3d at 1043. In light of the Second Circuit's decision in McCullock and the liberalizing purpose of Rule 702, I conclude that Dr. Gray's experience and training, as described above, is sufficient to qualify him to testify as an expert in this case.

C. Reliability and Relevance of Dr. Gray's Opinions

Once it is determined that a witness is qualified to testify as an expert, the inquiry turns to whether the proposed testimony will involve (1) scientific knowledge that (2) will assist the trier of fact to understand the evidence or to determine a fact in issue. See Fed.R.Evid. 702. "Expert testimony should be excluded if it is speculative or conjectural." Mancuso, 967 F. Supp. at 1441 (quoting Boucher v. Suzuki Motor Corp., 73 F.3d 18, 21 (2d Cir. 1996)). In particular, "[t]horny problems of admissibility arise when an expert seeks to base his opinion on novel or unorthodox techniques that have yet to stand the tests of time to prove their validity." McCullock, 61 F.3d at 1042.

Until 1993, the standard governing the admissibility of scientific evidence was whether the theory or methodology at issue was "generally accepted in the scientific community." See Frye v. United States, 54 App. D.C. 46, 47, 293 F. 1013, 1014 (1923). However, the Supreme Court has since concluded that the "general acceptance" test of Frye was "at odds with the `liberal thrust' of the Federal Rules and their `general approach of relaxing the traditional barriers to `opinion' testimony.'"Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 588, 113 S. Ct. 2786, 2794 (1993). Accordingly, the Court held that the Frye test had been superseded by the Federal Rules of Evidence, specifically Rule 702, and proceeded to outline the standards by which federal courts should evaluate scientific evidence under the Federal Rules. See Daubert, 509 U.S. at 589, 113 S. Ct. at 2794.

The Court began by examining the language of Rule 702, finding that "[t]he adjective `scientific' implies a grounding in the methods and procedures of science. Similarly, the word `knowledge' connotes more than subjective belief or unsupported speculation." Daubert, 509 U.S. at 590, 113 S. Ct. at 2795. Thus, the Court concluded, "in order to qualify as `scientific knowledge,' an inference or assertion must be derived by the scientific method." Id. Under Daubert, two steps are required to determine whether proposed expert testimony is admissible as scientific knowledge that will assist the trier of fact. First, the trial court must make "a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid." Daubert, 509 U.S. at 592-93, 113 S. Ct. at 2796. Second, if the reasoning or methodology is scientifically valid, the court must evaluate "whether [the expert's] reasoning or methodology properly can be applied to the facts in issue." Id. This requirement may also be described as ensuring that the evidence "fits" the facts of the case See id., 509 U.S. at 591, 113 S. Ct. at 2796.

In evaluating whether a proposed expert's reasoning or methodology is reliable, a court should consider the following non-exhaustive list of factors: 1) whether the theory or method can be, or has been, empirically tested; 2) whether the theory or method has been published or otherwise subjected to peer review; 3) with respect to a particular scientific technique, its known or potential rate of error; and 4) whether the theory or method is generally accepted in the relevant scientific community. See Daubert, 509 U.S. at 593-94, 113 S. Ct. at 2796-97. See also, Zuchowicz v. United States, 140 F.3d 381, 386 (2d Cir. 1998). While the Daubert Court emphasized that the court's inquiry must be flexible and "[t]he focus, of course, must be solely on principles and methodology, not on the conclusions that they generate." Id., 509 U.S. at 594-95, 113 S. Ct. at 2797, the Supreme Court recently clarified that

conclusions and methodology are not entirely distinct from one another. Trained experts commonly extrapolate from existing data. But nothing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence which is connected to existing data only by the ipse dixit of the expert. A court may conclude that there is simply too great an analytical gap between the data and the opinion proffered.

For the following reasons, this Court finds that Dr. Gray's testimony is inadmissible according to the standards set forth by the Supreme Court in Daubert and Joiner. Indeed, as discussed more fully below, although Dr. Gray uses different labels to describe plaintiff's condition, his expert opinion is, in essence, that plaintiff suffers from MCS. However, every federal court to consider the admissibility of expert testimony in support of a plaintiff's MCS claim has concluded that the proffered evidence is too speculative and untested to be received.

1. Whether Dr. Gray's Theory Has Been Empirically Tested

One relevant factor to be considered in evaluating the admissibility of scientific evidence is whether the theory or technique at issue can be, or has been, tested. See Daubert, 509 U.S. at 593, 113 S. Ct. at 2796. Plaintiff is simply unable to point to any scientific tests which support Dr. Gray's hypothesis that exposure to 4-PC can activate the human immune system and cause the "immunotoxicity syndrome" symptoms of which plaintiff complains.

Studies Cited by Dr. Gray

Plaintiff contends that Dr. Gray's opinion is supported by reports of empirical tests which establish that carpeting emits toxic gasses. When Dr. Gray was asked at his deposition to cite any published articles or studies linking 4-PC in any way to the symptoms described by Zwillinger, the only reference Dr. Gray could provide was to two or three articles published by Dr. Mark Van Ert at least eight years ago. According to Gray, the Van Ert articles associate exposure to 4-PC with "headaches, dizziness, confusional state, disorientation, general malaise, and a flu-like syndrome." Gray Tr. 213, 453-57. Although Dr. Gray stated that he had read other articles linking 4-PC to disorders of the immune system, he was unable to recall any titles or authors. See Gray Tr. 214, 520-21. Plaintiffs have provided a copy of one article co-authored by Dr. Van Ert as Pl.'s Ex. D-1. In that article, entitled Indoor Air Quality and Human Health, the authors note that 4-PC has been implicated as a "potential cause of illness," but also note that "knowledge of the health effects and toxicology of 4-PC is limited" and that its toxic properties are essentially unknown. See John B. Sullivan et al., Indoor Air Quality and Human Health in Hazardous Materials Toxicology 667, 678-80 (Pl.'s Ex. D-1). Moreover, Dr. Gray acknowledged during his deposition that Dr. Van Ert's work did not discuss whether exposure to 4-PC causes immunotoxicity syndrome because "the immunologic issues. . were not known at the time." Gray Tr. 456. Finally, defendants have submitted a letter from Dr. Van Ert, in which he states that,

[r]ecent studies aimed at elucidating the acute toxicity of 4-PCH . . . reveal a compound that is not particularly toxic. At the same time, animal inhalation studies at concentrations several orders of magnitude greater (16,000 ppb to 60,000 ppb) than those levels experienced by the public following installation of new carpet (4 ppb to 50 ppb), demonstrated no indication of irritant effects. Although the results of animal studies cannot be directly extrapolated to humans, this information suggests that 4-PCH should not serve as a irritant, at least for the majority of the public.

Letter from Dr. Mark Van Ert to Jeff Davidson dated Jan. 31, 1990 (Def.'s Ex. LLL). The letter goes on to state, "[w]ith regard to the issue of multiple chemical sensitivity (MCS), . . . evidence of an association with 4-PC is lacking." Id. Thus, the only scientist whose work Dr. Gray cited during his deposition as an authority supporting his conclusion has, in fact, repudiated it.

In reaching his conclusions, Dr. Gray also relies upon tests performed by Rosalind Anderson of Anderson Laboratories, indicating that mice, when exposed to the carpeting at issue in this case, suffer "severe sensory irritation." Defs.' Ex. NN at 7, see also Gray Tr. 296. In addition, Dr. Gray relies on other studies conducted by Dr. Anderson which evaluate the effects of carpet emissions on mice. See Pl.'s Mem. at 41. The results of these studies are reported in articles submitted by plaintiff as exhibits N, O, P and Q.

However, neither the tests conducted by Dr. Anderson on the carpet at issue in this case, nor the studies reported in the articles submitted as plaintiff's exhibits, purports to test whether exposure to gasses emitted by carpeting can alter the immune system and cause sensitivity to other, generally non-toxic chemicals. For example, in "Toxic Emissions from Carpets," 5 Journal of Nutritional and Environmental Medicine 375 (1995), Dr. Anderson states that "[w]hat we measure here is a simple form of toxicity — a direct acute irritant effect not involving classical allergic mechanisms, hypersensitivity or repeat exposures." Id. at 382 Moreover, in that same article, Dr. Anderson indicates the tentative nature of her conclusions by describing her results as "a step in the direction of providing an animal model of certain human aspects of one particular environmental illness." Id. The other articles authored by Dr. Anderson are similarly limited to attempts to measure allergic reactions in mice exposed to carpet gasses, and do not purport to test for changes in the immune systems of the mice.

In further support of her contention that summary judgment is inappropriate in this case, plaintiff has submitted numerous studies which have attempted to replicate Dr. Anderson's finding that carpet emissions may be toxic. These studies comprise part of plaintiff's Exhibits C and D.

Plaintiff relies upon the articles included in Exhibits C and D to support her assertion that "abundant independent scientific evidence exists which demonstrates that vapors offgassing from the same type of carpet cause the same types of injuries that the plaintiff suffered." See Pl.'s Mem. of Law at 19. These exhibits consist of forty-five scientific studies comprising several hundreds of pages. However, plaintiff fails to direct the Court's attention to any particular page, or even any particular study, within these extensive materials but simply refers to them en masse, and contends that they demonstrate that Dr. Gray's theory of causation has been the subject of empirical testing. Id. at 27, 34, 52. This approach attempts to place a burden on the Court which is properly borne by plaintiff. As noted by another court faced with a mass of material submitted without specific citation or analysis, "[d]istrict judges are not archeologists. They need not excavate masses of papers in search of revealing tidbits."Northwestern National Insurance Co. v. Baltes, 15 F.3d 660, 662 (7^th Cir. 1994).

Nevertheless, this Court has reviewed, at least in significant part, the studies submitted by plaintiff. To the extent that they have any relevance at all, the studies report the results of tests which essentially involve heating a carpet sample in an aquarium to a temperature significantly above room temperature, and then exposing mice, in a separate exposure chamber, to the heated air containing emissions from the carpet. This is essentially the same methodology used by Dr. Anderson to test the toxicity of the carpet sample at issue in this case. For the reasons set forth below, I conclude that these studies fail to demonstrate that Dr. Gray's conclusions have been subjected to empirical testing.

First, plaintiff offers no evidence to support the inference that, because mice experience toxic effects when they are exposed to heated carpeting, humans will experience symptoms when exposed to carpeting at room temperature. Indeed, a number of the studies raise questions regarding the reliability of data derived from the testing methodology because of the high temperatures used and the techniques employed to restrain the mice. See, e.g., Stott et al. at 241 (Pl.'s Ex. C-3); Beekman et al. at 873, (Pl.'s Ex. C-5); Muller and Black at 802-03 (Pl.'s Ex. C-24); Stadler et al. at 1085-86 (Pl.'s Ex. C-34). Moreover, while toxicological research frequently involves exposing laboratory animals to various doses of chemicals and then monitoring the animals' response to those chemicals, see Federal Judicial Center, Reference Guide on Toxicology 186-89 (1994), the data generated by animal testing must then be extrapolated to determine whether humans experience analogous effects, and if so, at what doses. See id. at 191. Plaintiff has failed to provide any evidence showing that the data generated from the animal studies cited in her memorandum of law may be reliably extrapolated to humans. Accordingly, there is no clear consensus that the methodology used to determine the toxicity of the carpet emissions is reliable.

More significantly, none of the studies provided to the Court report any correlation between the emission of 4-PC and toxicity in mice. Cf. Heller v. Shaw Industries, Inc., No. 95-7657, 1997 WL 535163, at *14-15 (E.D. Pa. 1997). To the contrary, the exhibits suggest either that the significance of 4-PC emissions is unknown, or that the testing revealed no connection between 4-PC and toxicity. See, e.g., Dietert and Hedge at 650-51 (Pl.'s Ex. C-1) ("While 4-PC emissions have been examined in several studies, the significance of these emissions to toxicity is generally unknown."); Stadler et al. at 1126 (Pl.'s Ex. C-2) ("At no time were mortality, neurotoxicity or other signs of toxicity associated with carpet exposure."); Stott et al. at 253 (Pl.'s Ex. C-3) ("The results of this study fail to substantiate findings . . . of neurotoxicity in mice exposed to carpet VOC"); Beekman et al. at 879 (Pl.'s Ex. C-5) (finding "[n]o clear treatment-related effects in mice exposed to vapors of 4-PCH, despite exposure to a near-saturated atmosphere"); Tepper et al. at 170 (Pl.'s Ex. C-28) (finding "no toxic effects associated with exposure to the off-gassing of the two tested complaint carpets"). Indeed, Dietert and Hedge found no demonstrable effects of carpet emissions on mice, noting that "[i]t is probable that the unique, positive results reported by Anderson reflect experimental artifact." Id. at 669 (Pl.'s Ex. C-1).

Finally, and of greatest import to the admissibility of Dr. Gray's testimony in this case, none of these studies even attempts to test the hypothesis that exposure to gasses emitted by carpeting can alter one's immune system and render an individual "chemically sensitive" to a wide variety of other substances. For example, plaintiff points to no study in which mice, having suffered an adverse reaction to gasses given off by carpeting, were then exposed to other substances which triggered symptoms, but which were not toxic to the mice before they were exposed to the carpeting.

Unable to point to any research linking exposure to 4-PC and the symptoms described by Gray as "immunotoxicity syndrome," plaintiff attempts to enhance the reliability of Dr. Gray's conclusion that defendants' carpet caused her symptoms by contending that new carpeting emits a variety of chemicals which may have brought about her illness. In his affidavit submitted in opposition to defendants' motion for summary judgment, Dr. Gray asserts that new carpeting emits up to 200 volatile gasses in addition to 4-PC, and that these additional gasses contributed to plaintiff's illness. See Gray Aff. ¶¶ 18-20. Plaintiff contends that, in assessing the reliability of Dr. Gray's expert opinion, this Court should consider that "[t]he Defendant's carpet emitted over 200 chemicals [and] [m]any of those chemicals have been linked to the symptoms experienced by the Plaintiffs [sic]." Pl.'s Mem. of Law at 55.

On August 9, 1995, this Court issued a Case Management Order requiring the parties to proceed with discovery in specified phases. See Docket Entry 22; Case Management Order (Amoco Reply Br., Ex. B). The Order required plaintiff to produce an expert report by December 1, 1995, and provided that the report include, among other things, "the chemical identity of the substance allegedly causing the personal injury." Case Management Order at 6. This date was subsequently extended to April 1, 1996.See Docket Entry 33.

As noted above, Dr. Gray submitted his expert opinion in the form of three letters, the most recent of which is dated April 6, 1996. In that letter, as in his undated letter, Dr. Gray attributes plaintiff's illness to exposure to 4-PC, and makes no claim or diagnosis that any symptoms experienced by plaintiff result from her exposure to any other chemical. See Defs. Ex. J, NN. Accordingly, any attempt at this stage of the litigation to offer proof that the carpeting at issue caused plaintiff's illness because it emitted gasses other than 4-PC is precluded by the Case Management Order. Moreover, plaintiff's contention that the other chemicals mentioned in Dr. Gray's opposing affidavit and in her memorandum of law have been linked to symptoms like those experienced by plaintiff is conclusory, and just as lacking in reliable science-based support as Dr. Gray's hypothesis that exposure to 4-PC caused Zwillinger's immune system to become hypersensitive to a broad variety of common substances.

In short, the studies cited by plaintiff demonstrate at most that carpets emit gasses which may cause irritation, and the majority of the studies refute even this limited contention. Plaintiff has failed to cite a single study which provides any empirical support for the suggestion that exposure to carpet gasses can make a person sensitive to other, generally safe, substances. Dr. Gray's Study

Dr. Gray is himself in the midst of conducting a study intended to test his theory that exposure to volatile organic compounds such as 4-PC can cause hyperactivity in the human immune system and produce the symptoms plaintiff has described. Dr. Gray's study involves eighty-nine patients who, according to Dr. Gray, report having experienced symptoms similar to those described by plaintiff after being exposed to low molecular weight volatile organic compounds. Gray's study is based on questionnaires completed by the patients regarding their symptoms, as well as on a series of blood tests, known as the "Gray's Panel," which are designed to determine the presence of various antibodies and other autoimmune markers. Gray Aff. ¶¶ 12-13.

In its discussion of research methods used in the field of epidemiology, the Federal Judicial Center's Reference Manual on Scientific Evidence states that observational studies "allow the researcher to draw stronger inferences about associations between risk factors and disease." Id. at 133. The Manual goes on to describe two major sub-groups of observational epidemiological studies: cohort studies and case-control studies. In a cohort study, the researcher "identifies two groups of individuals: (1) individuals who have been exposed to a substance that is thought might cause a disease and (2) individuals who have not been exposed. Both groups are followed for a specified length of time, and the proportion of each group that develops the disease is compared." Reference Manual on Scientific Evidence at 133-34. In a case-control study, "the researcher begins with a group of individuals who have the disease (cases) and then selects a group of individuals who do not have the disease (controls). Instead of observing each group, as is done in a cohort study, the researcher compares past exposures." See id. at 136. The Manual contains a similar discussion of the methods typically used when performing toxicological research. "Toxicological research usually involves exposing laboratory animals . . . or cells or tissues . . . to chemicals, monitoring their outcomes, such as cellular abnormalities or tumor formation, and comparing them to unexposed control groups." Id. at 186-87.

It appears that Dr. Gray is not using a control group of any type in his study. Rather, Gray's study seems to be comprised entirely of individuals who claim to have similar illnesses caused by exposure to similar chemicals, and does not include any individuals who were not exposed or who do not complain of symptoms. Gray's failure to include a control group of any type in his study raises serious concerns about the reliability of his work. Moreover, Dr. Gray has acknowledged that he has yet to finalize the results of his study, and that his research is still in the hypothesis stage. See Gray Tr. 224, 718-22. Cf. Golod v. Hoffman-LaRoche, 964 F. Supp. 841, 860 (S.D.N.Y. 1997) (excluding the testimony of plaintiff's expert regarding the biological mechanism by which a drug caused plaintiff's injuries, finding it to be "at most, scientifically-grounded speculation: an untested and potentially untestable hypothesis.").

Furthermore, the objective tests used by Dr. Gray in his study offer little or no information about the causes of immunotoxicity syndrome or multiple chemical sensitivity. A critical aspect of Dr. Gray's study is the testing performed on plaintiff, as well as on his other patients, to determine the levels of various antibodies and other autoimmune markers present in their systems. The studies cited by plaintiff do indicate that the presence of an antibody to a substance may help a physician to determine whether a patient has an allergy or sensitivity to that substance. See, e.g., Jean-Luc Malo et al., Prevalence of Occupational Asthma and Immunologic Sensitization to Guar Gum Among Employees at a Carpet-Manufacturing Plant, 86 J. Allergy Clin Immunol. 562 (1990) (Pl.'s Ex. C-6) (discussing blood tests used to measure antibodies to guar gum); Mary L. Hayden et al., Benzyl Benzoate Moist Powder: Investigation of Acarical Activity in Cultures and Reduction of Dust Mite Allergens in Carpets, 89 J. Allergy Clin. Immunol. 536 (1992) (Pl.'s Ex. C-8) (performing assay tests on subjects in study of dust mite allergens in carpets); Ebba Nexo et al., Extreme Fatigue and Malaise — A Syndrome Caused by Badly Cleaned Wall-to-Wall Carpets? (Pl.'s Ex. C-23) (drawing connection between antibodies to dust extracts found in inadequately cleaned carpets to upper respiratory problems suffered by workers). However, as Dr. Gray candidly acknowledged during his deposition, the results of the laboratory tests he arranged to have performed on plaintiff's blood do not alone justify the conclusion that plaintiff's symptoms are the result of exposure to 4-PC. Tr. 207-208. In fact, these test results offer no support for the conclusion that exposure to 4-PC or other gasses emitted by carpeting caused the observed changes in plaintiff's level of various antibodies.

As discussed above, the testing performed by Dr. Gray revealed that plaintiff has elevated levels of antibodies to isocyanate, formaldehyde, and trimellitic anhydride. Dr. Gray first met plaintiff Zwillinger approximately twenty-one months after her exposure to the defendants' carpet. Neverthless, although he noted at his deposition that the levels of isocyanate and formaldehyde reflected recent (within three weeks of the test) exposure to those substances, Gray Tr. 611-12, Dr. Gray attributes plaintiff's elevated levels to her exposure to 4-PC.

Gray acknowledges that none of these antibodies are specific to 4-PC, but theorizes that exposure to 4-PC can induce the presence of antibodies to substances other than 4-PC. See Gray Tr. 107 (acknowledging that the antibodies for trimellitic anhydride are not specific to 4-PC); 591 (acknowledging that antibodies to isocyanate are specific to isocyanate). Gray testified at his deposition that it is his understanding that anti-trimellitic anhydride antibodies are commonly present in individuals who have been sensitized by 4-PC. Gray Tr. 105. Dr. Gray therefore draws particular significance from plaintiff's elevated levels of antibodies to trimellitic anhydride, but admits that his understanding that this particular level is significant is based solely upon his "personal conversations with Dr. Broughton [of Antibody Assay Laboratories.]" Gray Tr. 577, 592-93; see also Gray Tr. 106, 211. "Other than [reports from and conversations with Broughton], I have not read other literature correlating elevations in trimellitic antibodies to trimellitic anhydride to solvent exposure." Gray Tr. 577. Moreover, Gray acknowledged that increased levels of anti-trimellitic anhydride antibodies may be caused by solvents generally, and do not necessarily indicate exposure to 4-PC. Gray Tr. 105, 590-591. Further, with respect to formaldehyde antibodies, Dr. Gray testified that "I can only cite experimental sources for other circumstances in which exposure to substance — to certain organic substances, specifically formaldehyde, are known to induce the presence of other antibodies to substances not related to the original exposure to formaldehyde. As to exactly what the underlying physiologic mechanism is, I am not sure that I understand it, I just know it occurs." Gray Tr. 592.

The significance of Gray's testing is also weakened by the final set of laboratory tests performed on Rhonda Zwillinger. The results of those tests were obtained during the break between Dr. Gray's first and second days of deposition, and revealed that her levels of antibodies were normalizing. Dr. Gray attributes this trend to the lifestyle that plaintiff has adopted. When questioned, "Doctor, is there any way to test this conclusion of yours that these antibodies are normalizing because of this life style that Rhonda Zwillinger is living?" Dr. Gray testified, "Efficably? Probably not . . . Well, again [there] may be . . . If you were to recreate the original exposure situation, if you could define it adequately and then subject the individual to such exposures, you might be able to test the hypothesis. Absent that, you could test it on a population basis." Gray Tr. 737-38. Plaintiff does not contend, of course, that any such tests have ever been performed.

For all of these reasons, I conclude that Dr. Gray's theory of causation has never been empirically tested. Thus, at least when evaluated pursuant to this Daubert factor, Dr. Gray's testimony should not be admitted at trial.

2. Whether Dr. Gray's Theory Has Been Published or Otherwise Subjected to Peer Review

The second Daubert factor is "whether the theory or technique has been subjected to peer review and publication." Daubert, 509 U.S. at 593, 113 S. Ct. at 2797. The fact that a particular theory has been submitted "to the scrutiny of the scientific community is a component of `good science,' in part because it increases the likelihood that substantive flaws in methodology will be detected." Id. However, the Court noted that "[p]ublication . . . does not necessarily correlate with reliability . . . in some instances well-grounded but innovative theories will not have been published. . . . [s]ome propositions, moreover, are too particular, too new, or of too limited interest to be published."Id.

In this case, as discussed above, the results of various tests regarding the effects of carpet emissions on mice have been published and subjected to peer review. However, Dr. Gray's own study, the only study cited by plaintiff which attempts to demonstrate a correlation between exposure to 4-PC and changes in the immune system, has not been completed, and its results have not been published. Although Dr. Gray has discussed the possibility of publication with the Archives of Environmental Health, his research, as noted above, is still in progress. See Gray Tr. 219. Thus, Dr. Gray's hypothesis that exposure to 4-PC causes "immunotoxicity syndrome" or multiple chemical sensitivity has not been subjected to peer review.

3. Known or Potential Rate of Error

A third factor for courts to consider in evaluating the reliability of a particular scientific technique is its "known or potential rate of error . . . and the existence and maintenance of standards controlling the technique's operation." Daubert, 509 U.S. at 594, 113 S. Ct. at 2797. Because there are no completed empirical studies purporting to find a correlation between exposure to 4-PC and sensitivity to a broad variety of otherwise safe substances, there is no specific "error rate" to consider. However, there are aspects of Dr. Gray's ongoing study which suggest that Gray's work may suffer from a high potential rate of error.

First, as noted above, Dr. Gray's study, like his expert opinion in this case, relies in large part upon the exposures and symptoms described by his patients; Gray has no objective test for determining the cause of the elevated antibody levels he claims to be discerning in his patients' blood. However, experts point out that patient histories are often not a reliable source of data. For example, the Reference Manual on Scientific Evidence notes in its discussion of case-control studies that individuals who have a disease may be more likely to recall a past exposure than individuals who do not have a disease, thus creating a potential for biased data inaccurately reflecting greater exposure to a supposed toxin among subjects with a disease. See id. at 136-37; see also Iris R. Bell et al., Self-Reported Illness from Chemical Odors in Young Adults Without Clinical Syndromes or Occupational Exposures, 48 Archives of Environmental Health 6 (1993) (Pl.'s Ex. C-4) (noting the limited reliability of self-reporting as a methodology); D. Norback et al., Asthmatic Symptoms and Volatile Organic Compounds, Formaldehyde, and Carbon Dioxide in Dwellings, 52 Occupational and Environmental Med. 388 (1995) (Pl.'s Ex. C-21) (noting that response bias due to awareness of exposure may cause a general over-reporting of symptoms in exposed groups). Accordingly, the error rate for a study which is based substantially on self-reporting of symptoms is likely to be substantial.

Dr. Gray's decision not to employ a control group as part of his study is also likely to impact adversely upon the reliability of his results. For example, in Casey v. Ohio Medical Products, 877 F. Supp. 1380 (N.D. Cal. 1995), the district court rejected plaintiff's expert's reliance on case studies because such reports "simply described reported phenomena without comparison to the rate at which the phenomena occur in the general population or in a defined control group; do not isolate and exclude potentially alternative causes; and do not investigate or explain the mechanism of causation." Id. at 1385. A similar analysis may be applied to this case.

For the foregoing reasons, it appears that any empirical results reached by Dr. Gray's study are likely to be marred by a high rate of error. Accordingly, consideration of this Daubert factor also indicates that Gray should not be permitted to testify at trial.

4. Whether Dr. Gray's Testimony "Fits" the Facts of This Case

Before admitting expert testimony, a trial court must find not only that it is reliable, but also that it is "sufficiently tied to the facts of the case that it will aid the jury in resolving a factual dispute." Daubert, 509 U.S. at 591, 113 S. Ct. at 2796. In this case, even if Dr. Gray could reliably testify that, as a general matter, exposure to certain chemicals may activate the immune system and render an individual "chemically sensitive" to a broad range of substances, his deposition testimony demonstrates that he would be unable to tie that conclusion to the facts presented by this case.

In a toxic tort case, an expert seeking to testify on that subject generally must employ principles and methods of toxicology, even if he or she is not a toxicologist. See, e.g., Mancuso, 967 F. Supp. at 1445. A scientifically valid opinion on causation in a toxic tort case typically requires an analysis of whether there is a "biologically plausible theory" by which the disease can be related to the alleged chemical exposure; an examination of whether the plaintiff was exposed to the chemical in a manner that can lead to absorption into the body; and an opinion as to whether the dose of the chemical to which the plaintiff was exposed is sufficient to cause the symptoms in issue. See Reference Manual on Scientific Evidence at 201; see also Wintz by and through Wintz v. Northrop Corp, 110 F.3d 508, 513 (7th Cir. 1997) (upholding exclusion of expert's testimony where expert knew only that infant plaintiff's mother had worked with bromide, but did not know how the frequency and quantity of her exposure, the size of the room, its ventilation capacity, or whether she wore a protective mask).

In evaluating the relationship between dose and response, the expert must establish not only "general causation," (that, according to scientific literature, levels of the toxin comparable to those received by the plaintiff can cause the specific types of injuries she alleges) but also "specific causation" (that, more likely than not, the toxin caused the plaintiff's injuries in this particular case). To establish specific causation, other possible causes for the symptoms experienced by plaintiff should be excluded by performing a "differential diagnosis." A differential diagnosis typically includes a physical examination, clinical tests, and a thorough case history. See Mancuso, 967 F. Supp. at 1445; see also Wright v. Williamette Industries, Inc., 91 F.3d 1105, 1107-08 (8th Cir. 1996).

When examined in light of these fundamental methods of toxicology, the inadequacy of the steps taken by Dr. Gray in reaching his diagnosis of plaintiff become apparent. First, Gray has conceded that his knowledge of the specific effects of 4-PC in individual cases is limited. For example, Gray has admitted that he does not know what level of 4-PC must be present to produce a toxic effect in humans. Gray Tr. 217. Indeed, during his deposition, Gray expressed interest in learning more about "the physical properties of 4-PC." Id. at 499. Furthermore, as discussed above, Gray has failed to "establish `general causation,' by demonstrating that, according to scientific literature, levels of the toxin comparable to those received by plaintiff can cause the specific types of injuries [s]he alleges." Mancuso, 967 F. Supp. 1445.

In fact, Gray has no information about plaintiff's level of exposure. At his deposition, Gray acknowledged that he did not know the level of 4-PC to which plaintiff was actually exposed, and could not determine the level of 4-PC present in Zwillinger's system after exposure because too much time had passed between her exposure and the time he first saw her. See Gray Tr. 86-88. Gray further conceded that he did not know the amount of carpeting that had been installed, or whether it had been installed inside or outside of plaintiff's apartment, noting only that "[i]t would be helpful to know whether it was inside or outside of the apartment and whether the air handling system was common to both and recirculated the air through both. Those would be helpful pieces of information . . . [i]f one were going to attempt to generate a precise model of quantification or an estimate of exposure level, that data would be relevant." Gray Tr. 423-424. Thus, Gray has little or no idea of "the dosage of the toxin at issue to which plaintiff was exposed." Mancuso, 967 F. Supp. at 1445.

Dr. Gray also testified that, although he has many patients who complain of symptoms caused by exposure to everyday substances, Rhonda Zwillinger is the first patient he has treated for exposure to 4-PC, and that plaintiff is the only one of the patients in his study who claims that exposure to 4-PC was the "primary triggering event" for her symptoms. See Gray Tr. 77, 222, 230. In fact, Gray was unsure at the time of his deposition whether any of the patients in the study have claimed that their symptoms were caused by exposure to carpets. See id. at 724.

Finally, although he bases his expert opinion on causation in large part upon Zwillinger's report that her symptoms began just after she was exposed to defendants' carpet, Gray Tr. at 72, 119, Gray acknowledged that he did not have Zwillinger's complete medical records, Gray Tr. at 55, and that he had no baseline data, taken prior to Zwillinger's exposure, from which to compare the test results he obtained after exposure. Gray Tr. 630-631. Gray further conceded that he was unable to rule out the possibility that Zwillinger's symptoms were caused by her exposure to formaldehyde emitted by the plywood which was put down about two weeks before the carpeting was installed. Gray Tr. at 253, 287; Zwill. Tr. 89-90. Gray's lack of familiarity with plaintiff's medical history is especially critical in light of the persuasive documentary proof submitted by defendants, indicating that, long before the carpeting in issue was installed in the hallway of her building, plaintiff complained to various doctors that she was experiencing many of the symptoms she now attributes to defendants' carpeting. See Aff. of Richard P. Marin, ¶¶ 76-89 and cited exhibits. Thus, Gray has failed to conduct a thorough, scientific differential diagnosis. Cf. Zuchowicz, 140 F.3d at 385 (concluding that expert's testimony with respect to causation should be admitted because "based on the temporal relationship between the overdose and the start of the disease and the differential etiology method of excluding other possible causes.") (emphasis added).

As the discussion above demonstrates, Dr. Gray has insufficient information regarding plaintiff's medical history, plaintiff's prior exposure to other "VOCs," the nature and extent of plaintiff's exposure to 4-PC, or the manner in which 4-PC affects the immune system, to offer relevant, scientific expert testimony in this case. Accordingly, even if Dr. Gray's general theories were supported by reliable scientific evidence, plaintiff has failed to demonstrate that those theories fit the particular facts of this case sufficiently well to warrant admitting Dr. Gray's testimony at trial.

5. Whether Dr. Gray's Conclusions Are Generally Accepted in the Relevant Scientific Community

Although Daubert clarified that the Federal Rules of Evidence supersedes the "general acceptance" test of Frye, the Court noted that "`general acceptance' can yet have a bearing on the inquiry." Daubert, 509 U.S. at 594, 113 S. Ct. at 2797. Indeed, "a known technique which has been able to attract only minimal support within the community . . . may properly be viewed with skepticism." Id. As discussed above, plaintiff has failed to identify any published studies or other indicia that scientists generally accept the existence of a correlation between exposure to 4-PC and heightened sensitivity to everyday substances.

Moreover, every federal court that has considered the admissibility of expert testimony concerning multiple chemical sensitivity has found the basis for the diagnosis to be too speculative to qualify as "scientific knowledge" under Daubert. See, e.g., Frank v. State of New York, 972 F. Supp. 130, 137 (N.D.N.Y. 1997) (noting that "the controversy surrounding MCS remains to be `settled by the methods of science rather than by the methods of litigation'" (quoting Sanderson v. Internat'l Flavors and Fragrances, Inc., 950 F. Supp. 981, 1002 (C.D. Cal. 1996))); see also Summers v. Missouri Pacific Railroad System, No. 96-7038, 1997 WL 786640 at *2 (10th Cir. Dec. 23, 1997); Bradley v. Brown, 42 F.3d 434, 438-39 (7th Cir. 1994); Carlin v. RFE Industries, Inc., No. 88-CV-842, 1995 WL 760739 (N.D.N.Y. 1995).

Apparently aware that courts have uniformly rejected expert testimony presenting a diagnosis of MCS, see Pl.'s Mem. of Law at 23 n. 6, plaintiff contends that her proposed expert, Dr. Gray, diagnosed her with "immunotoxicity" and "toxic encephalopathy," and that these conditions are distinguishable from MCS. See Pl.'s Mem. of Law at 22. Plaintiff asserts that defendants incorrectly equate immunotoxicity syndrome and MCS, arguing that "multiple chemical sensitivity is a colloquially used term that was used by the plaintiff during a conversation with Dr. Gray . . . It did not appear as a `diagnosis' in Dr. Gray's chart regarding the Plaintiff." See id. at 22-23.

The record in this case belies plaintiff's current contention that she and Dr. Gray genuinely and legitimately distinguish between MCS and "immunotoxicity syndrome." For example, plaintiff's complaint describes her illness as "Immunotoxicity Syndrome a/k/a/ Multiple Chemical Sensitivity." Compl. ¶ 2. Similarly, in his undated opinion letter in this case, Dr. Gray listed his primary diagnosis as "Immunotoxicity Syndrome (aka Multiple Chemical Sensitivity, Environmental Illness, Variant Neurotoxicity Syndrome), and Toxic Encephalopathy." Def.'s Ex. J. When asked during his deposition to define immune toxicity syndrome and multiple chemical sensitivity, Dr. Gray was unable to draw a meaningful distinction between them, stating that "[m]ultiple chemical sensitivity and environmental illness . . . are colloquially used terms which in my practice I have commonly found in association with demonstrable states of immune toxicity." Gray Tr. at 123.

Moreover, the definitions of MCS in the literature describing it, and in the cases precluding testimony about it, are essentially identical to the definition of immunotoxicity syndrome provided by Dr. Gray during discovery in this lawsuit. According to the Federal Judicial Center, a diagnosis of MCS describes a condition in which "various kinds of environmental insults may depress a person's immune system so that the exposed person . . . becomes hypersensitive to other chemicals and naturally occurring substances." See Federal Judicial Center, Reference Manual on Scientific Evidence 73 (1994). Similarly, inFrank, the Court analyzed a variety of definitions of MCS, and found that all described a disorder with multiple symptoms, affecting multiple organs, as a result of exposure to a wide variety of chemicals at levels easily tolerated by most people. 972 F. Supp. at 132 n. 2. See also Brown, 42 F.3d at 436 n. 1 ("MCS is a multi-symptom disorder which can be caused by exposure to chemical or environmental instants. MCS results in hyper-sensitivity to what would normally be acceptable doses of chemicals. MCS's symptoms can include respiratory irritation, shortness of breath, fatigue and nausea.").

Dr. Gray's diagnosis in this case falls within these definitions of MCS. Plaintiff's complaints in this case include nausea, dizziness and fatigue. Zwill. Tr. 97-100, 158. Moreover, during his deposition, Dr. Gray testified that "[i]mmune toxicity refers to either a suppressive or an overly active immune state occurring in association with an environmental toxin." Gray Tr. 122. Plaintiff has also submitted a lengthy article on immunotoxicity in support of her attempt to distinguish that diagnosis from MCS. See Bradford O. Brooks and John B. Sullivan, Jr., "Immunotoxicology" in John B. Sullivan, Jr., and Gary R. Krieger, Hazardous Materials Toxicology: Clinical Principles of Environmental Health 190-214 (1992) (Pl.'s Ex. D3). The authors of that article define immunotoxicity as "the adverse effects of an unsuitable immune response caused by the direct or indirect action of a xenobiotic. It may also result from an immunologically mediated host response to a xenobiotic, its metabolites, or host antigens altered by these substances." Id. at 192-93. One class of immunotoxicity is "hypersensitivity," and the authors note that "characteristics of the chemicals or other xenobiotics that sensitize an individual may not necessarily be the same as those that elicit an allergic response." Id. at 200. Thus, both MCS and immunotoxicity syndrome purport to describe a change in a patient's immune system, caused by exposure to one substance, which renders the patient hypersensitive to a variety of other common substances which do not cause toxic effects in most people. This Court discerns no meaningful distinction between MCS and immunotoxicity syndrome.

Other courts have recently confronted attempts, like Dr. Gray's here, to avoid the impact of the rulings cited above by using new labels to describe diagnoses essentially identical to MCS. Not surprisingly, these courts have determined the admissibility of the proffered evidence by examining the substance of the expert's testimony, and not the labels he or she used. For example, inSummers, 1997 WL 786640 at *2, the Tenth Circuit upheld the district court's exclusion of the testimony of plaintiff's expert, where the expert claimed that plaintiff was suffering from "chemical sensitivity, but the court accepted defendants' argument that the expert was "not in fact making that diagnosis, but is instead applying a scientifically valid label to a scientifically invalid diagnosis of `multiple chemical sensitivity' (`MCS')." Similarly, in Treadwell v. Dow-United Technologies, 970 F. Supp. 974, 982 (M.D. Ala. 1997), the district court noted that while plaintiff's proposed expert "carefully phrased his diagnosis as `multiple sensitivities to other antigens in her environment . . . it appears that his diagnosis is, at least in part, one of MCS," and excluded that portion of the expert's proffered testimony.

The expert opinion of Dr. Gray is, in essence, that exposure to 4-PC emitted by defendants' carpet has caused plaintiff to suffer from MCS. The hypothesis that exposure to gasses given off by carpeting, or any other chemical, may cause MCS is not generally accepted in the scientific community, and has repeatedly and uniformly been held to be too speculative and untested to form the basis of admissible expert testimony at trial. Plaintiff cannot avoid the force of these holdings by renaming her diagnosis "immunotoxicity syndrome."

Conclusion

A trial court is responsible for ensuring that scientific testimony is both relevant and reliable. Daubert, 509 U.S. at 589, 113 S. Ct. at 2795. In evaluating whether the testimony of a proposed expert is reliable, "`[c]ourts are particularly wary of unfounded expert opinion when causation is the issue." In re Agent Orange Product Liability Litigation, 611 F. Supp. 1223, 1249 (E.D.N.Y. 1985), aff'd 818 F.2d 187 (2d Cir. 1987),cert. denied, 487 U.S. 1234, 108 S.Ct. 2898 (1988). Moreover, "[t]he uncertainty of evidence in [toxic tort] cases, dependent as it is upon speculative scientific hypotheses and epidemiological studies, creates a special need for robust screening of experts and gatekeeping under Evidence Rules 403 and 703 by the court." Id. at 1260.

While no one Daubert factor is dispositive, plaintiff has failed to demonstrate that Dr. Gray's methodology is reliable under any of the factors set forth by the Supreme Court. Further, in evaluating the conclusions that Dr. Gray has drawn from his research and treatment of plaintiff, it is apparent that there is "simply too great an analytical gap between the data and the opinion proffered." General Elec. Co. v. Joiner, 118 S. Ct. at 519. For the foregoing reasons, Dr. Gray's testimony must be excluded as unreliable under Daubert and Joiner.

Because Dr. Gray's testimony is plaintiff's only evidence of causation, defendants' motion for summary judgment is hereby granted. Although only defendants Amoco Chemical and Wellco Carpet have formally moved for summary judgment, this Court's conclusion that Dr. Gray's testimony is not admissible is fatal to plaintiff's claims against all defendants.

Accordingly, the Clerk of the Court is directed to enter judgment in favor of all defendants, and to dismiss plaintiff's claims.

So Ordered.