## Facts

- Former employees (and survivors) of a tire plant in Cumberland, Maryland alleged occupational diseases (including cancers, cardiovascular disease, and lung disease) from chemical exposures at work.
- The plant used roughly 200 chemicals; Goodyear, the parent company and a supplier, provided about 10% of them.
- Plaintiffs claimed Goodyear-supplied chemicals were a substantial contributing cause of their diseases.
- Similar prior suits by plant workers against Goodyear had ended in summary judgment for Goodyear on causation.
- In this consolidated litigation, plaintiffs submitted expert affidavits asserting certain Goodyear-supplied chemicals substantially contributed to the diseases.
- The affidavits did not explain methodology, dose or exposure levels, disease-specific causal mechanisms, individualized exposure histories, timing, or alternative causes.

## Issues

1. Whether plaintiffs’ expert affidavits satisfied Federal Rule of Evidence 702 and Daubert such that the opinions on causation were admissible and sufficient.
2. Whether plaintiffs produced enough admissible evidence of product-specific exposure and medical causation to create a genuine dispute of material fact and defeat summary judgment.

## Decision

- The court granted summary judgment for Goodyear in all consolidated cases.
- It held plaintiffs failed to provide admissible expert evidence establishing that Goodyear-supplied chemicals were a substantial contributing cause of the alleged diseases.
- The court found the expert opinions conclusory and insufficiently tied to the facts of individual plaintiffs’ exposures and conditions.

## Legal Principles

- In complex toxic-exposure cases, plaintiffs generally must present competent expert testimony to prove causation.
- Under Rule 702 and Daubert, expert testimony must be reliable (methodologically supported) and relevant (fit the case facts).
- Conclusory expert assertions, without explained methods, exposure assessment, dose-response analysis, or reasoned linkage between substance and disease, may be excluded or deemed insufficient.
- Maryland tort causation in this setting requires product identification/exposure evidence and proof that the defendant’s product was a substantial factor (or substantial contributing cause) of the harm.
- Where multiple potential sources and chemicals exist, plaintiffs must provide product- and plaintiff-specific evidence distinguishing the defendant’s substances from other exposures and addressing alternative causes.

## Conclusion

Because plaintiffs’ expert submissions did not provide methodologically supported, product-specific, and individualized causation analyses connecting Goodyear-supplied chemicals to each plaintiff’s disease, the court held no reasonable jury could find causation on the record and entered summary judgment for Goodyear.


Aldridge v. Goodyear Tire & Rubber Co., 34 F. Supp. 2d 1010 (D. Md. 1999)