## Facts

- Robert Coene worked as a technician at Eastman Kodak Company in Rochester, New York from 1992–2002 and spent about 80% of his time making prototype camera parts using selective laser sintering (SLS), an early form of 3D printing.
- SLS used lasers to selectively melt or sinter powdered materials into solid parts; the work also included post-processing steps such as brushing and sandblasting that generated dust.
- Kodak used two powders, DuraForm GF and LNC-7000, described in materials documentation as roughly 50% glass (silica) and 50% polymer (nylon or resin).
- Silica can be amorphous or crystalline; inhalation of respirable crystalline silica is associated with silicosis and related pneumoconiosis.
- Kodak’s silica was described as amorphous, but plaintiffs contended that materials sold as “amorphous” may contain some crystalline silica and that high-heat processing can convert amorphous silica to crystalline silica.
- From 1992–1998, while performing SLS and associated cleaning/post-processing tasks, Coene wore a 3M 8710 disposable respirator intended to reduce inhalation of airborne dust.
- Coene later developed pneumoconiosis/silicosis and lung scarring, which plaintiffs alleged resulted from inhaling respirable crystalline silica and polymer dust despite use of the 3M respirator.
- Coene and his spouse sued 3M Company, alleging the respirator failed to protect him from harmful dust exposure.
- Plaintiffs retained Dr. William Meggs, a physician and toxicologist, who reviewed the SLS process, the powders’ composition, technical literature on silica crystallization in high-temperature processes, and Coene’s medical records.
- Meggs opined that SLS could generate respirable crystalline silica and that exposure to crystalline silica caused Coene’s silicosis/pneumoconiosis, with nylon/resin dust contributing to lung scarring.
- 3M moved (by a renewed summary-judgment motion) to exclude Meggs under Federal Rule of Evidence 702 and Daubert and argued that, without his testimony, plaintiffs could not prove causation.

## Issues

1. Whether Dr. Meggs’s opinions on crystalline-silica generation and medical causation were admissible under Federal Rule of Evidence 702 and Daubert.
2. Whether, with Meggs’s opinions admitted, 3M was entitled to summary judgment on causation.

## Decision

- The court denied 3M’s renewed motion for summary judgment.
- The court admitted Dr. Meggs’s causation testimony under Rule 702.
- The court found Meggs sufficiently qualified as a physician and toxicologist to testify about toxic exposure and medical causation even if he was not a respirator designer or SLS engineer.
- The court held Meggs relied on adequate facts and data, including descriptions of the SLS process, powder composition documents, published literature on silica behavior under heat, and Coene’s medical records.
- The court concluded that 3M’s objections largely challenged the strength of Meggs’s inferences and competing interpretations of the literature, which were matters for cross-examination and the factfinder rather than reasons for exclusion.
- Because Meggs’s testimony created a triable dispute on exposure and causation, judgment as a matter of law was not warranted.

## Legal Principles

- Rule 702 permits opinion testimony from a qualified witness if the testimony will help the trier of fact, is based on sufficient facts or data, and is the product of reliable principles and methods reliably applied to the case.
- Under Daubert, the court’s screening function focuses on method and reasoning, not on choosing between competing factual accounts or deciding which side’s scientific view is correct.
- In toxic-tort and products-liability cases, a medical toxicologist may base causation opinions on process descriptions, composition information, scientific literature, and medical records; the absence of direct exposure measurements is not necessarily fatal when the reasoning is scientifically supported.
- Disputes about alternative explanations, the completeness of an expert’s review, or the weight to give scientific sources typically affect credibility and weight, not admissibility, when the expert’s method is acceptable.
- On summary judgment, when admissible expert testimony supports plaintiffs’ theory and the record contains contested facts about exposure and causation, those disputes are for the jury.

## Conclusion

In *Coene v. 3M Company*, the Western District of New York held that plaintiffs’ physician-toxicologist could testify that Kodak’s SLS 3D-printing process generated respirable crystalline silica and that exposure to crystalline silica (and polymer dust) caused Coene’s lung disease despite his use of a 3M 8710 respirator; because that testimony was admissible under Rule 702 and created genuine disputes of material fact, the court denied 3M’s renewed motion for summary judgment.


Coene v. 3M Company, 2017 WL 1046749 (2017)