## Facts

- Central Illinois Public Service Company (CIPS) historically owned and operated a manufactured gas plant site in Taylorville, Illinois.
- The gasification process left coal tar and related contaminants at the site; plaintiffs alleged CIPS knew the materials were hazardous.
- In the mid-1980s, CIPS began site remediation, including excavation and removal of contaminated soils.
- Residents and workers reported contemporaneous symptoms during cleanup that plaintiffs attributed to airborne releases and dust containing coal-tar constituents, including PAHs.
- Between March 1989 and August 1991, three infants and one teenager in Taylorville were diagnosed with neuroblastoma; all lived within several miles of the site.
- Plaintiffs (parents suing individually and on behalf of their children) alleged that CIPS’s remediation acts and omissions caused the children’s cancers.
- After a four-month jury trial, the jury returned a $3.2 million verdict against CIPS; the trial court entered judgment and the appellate court affirmed.

## Issues

1. Whether plaintiffs’ causation experts were properly admitted under the Frye “general acceptance” test for scientific evidence.
2. Whether the evidence was sufficient to prove general and specific causation, including whether plaintiffs had to quantify exact exposure levels to establish proximate cause.
3. Whether the evidence supported findings that CIPS breached duties of reasonable care and warning in planning and conducting remediation.
4. Whether plaintiffs could maintain a common-law public nuisance claim and whether the evidence supported the nuisance verdict.

## Decision

- The Illinois Supreme Court affirmed the judgment for plaintiffs.
- The trial court did not abuse its discretion in admitting plaintiffs’ expert causation testimony under Frye.
- The evidence permitted a reasonable jury to find CIPS’s conduct during remediation was a substantial factor in causing the children’s neuroblastoma without precise numerical exposure quantification.
- The record supported findings that CIPS breached duties related to safe remediation practices and adequate warnings.
- The public nuisance claim remained viable at common law and was supported by the evidence.

## Legal Principles

- Under Frye, the admissibility question is whether the underlying scientific methodology is generally accepted in the relevant field, not whether the expert’s ultimate conclusion is correct.
- In toxic-tort cases involving rare diseases and limited epidemiological data, experts may rely on generally accepted inferential methods, including toxicology, animal studies, analogous data, and reasoned extrapolation.
- Causation may be proven by expert and circumstantial evidence; exact dose reconstruction is not an absolute prerequisite when the evidence supports a substantial-factor inference.
- Common-law public nuisance survives independent of statutory provisions and may be based on conduct that substantially and unreasonably interferes with public rights such as public health.

## Conclusion

The court left intact a $3.2 million jury verdict, holding that plaintiffs’ toxic-tort causation experts satisfied Frye and that the combined expert and circumstantial evidence supported findings of negligence and common-law public nuisance arising from remediation-related releases from the contaminated site.


Donaldson v. Cent. Ill. Pub. Serv. Co., 199 Ill. 2d 63, 767 N.E.2d 314 (Ill. 2002)