Expert Testimony Regarding Asthma Risk and Causation Based on Plaintiff’s Exposure and Peer-Reviewed Scientific Literature Concerning Effects of Product Ingredients Held Admissible

In Maston v. Poirier, 81 Mass. App. Ct. 1131 (Apr. 24, 2012), plaintiff allegedly developed chronic asthma from exposure to a disinfecting product used by defendants’ cleaning business which plaintiff hired to clean her basement after a city sewer backup. Plaintiff and her husband brought suit in Massachusetts Superior Court asserting, among other claims, breach of the implied warranty of merchantability (the Massachusetts near-equivalent of strict liability) and violation of Mass. Gen. L. ch. 93A (the Massachusetts unfair and deceptive practices statute) based on defendants’ failure to warn of the dangerous conditions resulting from their use of the cleaning product. Because plaintiff had not been advised of the need to properly ventilate the area and stay away from it until dry, she entered the basement to perform additional cleaning as soon as defendants left, and continued to work in the basement over several days. Following a bench trial, at which plaintiffs’ expert testified that chemical compounds in the product have the ability to cause asthma and respiratory sensitization and that plaintiff’s exposure caused her injuries, the court entered judgment for plaintiffs. Defendants appealed to the Massachusetts Appeals Court, arguing that (i) plaintiff’s claims failed as a matter of law because her exposure to the cleaning product came about as a result of defendants’ provision of services and not the sale of goods, (ii) the expert’s causation testimony was scientifically unreliable, and therefore inadmissible, and (iii) without expert testimony, there was insufficient evidence to support the judge’s finding of a duty to warn.

First, the appellate court refused to consider defendants’ argument, raised for the first time on appeal, that there could be no breach of the warranty of merchantability, and hence no liability under ch. 93A, because plaintiff’s alleged injury was caused by defendants’ provision of services and not the sale of goods. Although the court did not resolve the goods/ services argument, it did take note of plaintiffs’ response that, in addition to providing clean-up services, defendants had supplied the cleaning product and thus the transaction was “predominantly” a sale of goods.

Turing to the merits, the court held that the evidence was sufficient to permit the trial judge to find that defendants were required to warn or instruct plaintiffs about hazards associated with the cleaning product and necessary precautions after its use. In particular, it was within the trial judge’s discretion to rely upon the testimony of plaintiffs’ expert concerning general and specific causation and to deny defendants’ motion to strike that testimony. The appeals court found the expert sufficiently qualified by his education, experience and research in the fields of toxicology, medicine and environmental health. Moreover, the court found the expert’s causation opinion met the reliability standards of Commonwealth v. Lanigan, 419 Mass. 15 (1994) (accepting the basic reasoning of Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993), which requires the proponent of expert testimony to demonstrate both its reliability, and its relevance or “fit” to the legal issues), as it was based upon (i) the existence of quaternary ammonium compounds (“QUATS”) in the product, (ii) peer-reviewed, scientific literature linking QUATS to the development of asthma and respiratory sensitization, (iii) the history of plaintiff’s exposure, (iv) her symptoms and (v) the results of a methacholine challenge test, which confirmed a diagnosis of hyperactive airways. Neither the lapse of time between plaintiff’s exposure and her asthma diagnosis nor the absence of quantitative analysis of exposure rendered the expert’s opinion inadmissible; rather, these were issues to be explored on cross-examination and through the testimony of defendants’ expert.