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February 14, 2013

High Standard Of Proof Of Causation In Toxic Tort Cases For Plaintiffs' Experts

A New York appellate court in Cleghorne v. City of New York, 99 A.D.3d 443; 952 N.Y.S.2d 114 (1st Dep't October 4, 2012), reaffirmed New York's continued commitment to holding a plaintiff's experts to a high standard of proof of causation in toxic tort cases. The Appellate Division, First Department, held that bare allegations of plaintiff's exposure to various allergens and toxic substances resulting in illness was not enough. The Court concluded that a plaintiff must: offer proof of exposure to a specific toxin or allergen; quantify the level of exposure to some degree; and demonstrate that such level of exposure was sufficient to produce the alleged injuries.

Plaintiff, Wayne Cleghorne, was a school teacher who was relocated to a new facility just before the 2000–2001 school year commenced. Shortly thereafter, she developed a persistent cough and other respiratory problems, which first appeared after she cleaned her classroom and a storage area in the new facility. She was later diagnosed with asthma, and ultimately bronchitis.

Defendants, the Board of Education, the City of New York, and two principals of the school, moved for summary judgment, arguing a lack of causation, nonexistent proof of exposure to toxins at the new facility, and that Plaintiff had a pre-existing asthmatic condition. Defendants' expert concluded that Plaintiff's asthma developed prior to moving to the new location, the alleged "environmental contaminants" did not cause her condition, and that Plaintiff suffered allergies to several common allergens such as tree and ragweed pollen, dust mites, dogs, cats, and mold spores, which were not exclusive to the new facility.

On her cross-motion for summary judgment, Plaintiff submitted her own affidavit setting forth the conditions at the school and detailing her efforts to keep her classroom free of dust, dirt, rodent droppings and carcasses, cobwebs, dead insects, mildew and mold. Plaintiff also submitted the affidavit of an expert, who opined Plaintiff did not have asthma prior to 2000, but instead suffered from a respiratory condition described as asymptomatic "airway hyper responsiveness" (AHR). The expert concluded Plaintiff's condition was triggered by "high-level" exposure to and the daily inhalation of contaminants at the new facility.

Defendants moved to preclude Plaintiff's expert report because his opinion and methodology were not generally accepted in the medical community. Moreover, Defendants argued that Plaintiff had not reliably shown the levels of allergens or toxins that she was allegedly exposed to, or whether they were sufficient to cause her asthma. The lower court denied both summary judgment motions.

The First Department unanimously reversed the lower court's denial of Defendants' summary judgment motion. The Court concluded that the Complaint should have been dismissed. Plaintiff failed to identify the specific toxin or allergen that triggered her symptoms, failed to quantify the level of exposure, and failed to posit – through her expert – that the level of exposure was sufficient to cause the alleged injury. The Court criticized Plaintiff's expert and "method," emphasizing that the expert simply accepted Plaintiff's "anecdotal allegations" of exposure to contaminants in unspecified quantities, and concluded that Plaintiff developed asthma as a result without any scientific measurement or accepted method of extrapolation. The failure to identify the threshold level of exposure necessary for general causation of injury alone warranted dismissal.

The rule that can be gleaned from Cleghorne, is that a plaintiff in a toxic exposure case must address and offer proof of exposure to specific toxins or allergens; quantify the level of exposure to some degree; and demonstrate that such level of exposure was sufficient to produce the alleged injuries. Failure to do so should result in dismissal.

If you require further information regarding the information presented in this Legal Alert and its impact on your organization, please contact Matthew J. Larkin, Chair of the Torts & Products Liability Defense Practice Area at (315) 425-2805 or


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